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Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 25 - 25
23 Jun 2023
Ricard M Pacheco L Koorosh K Poitras S Carsen S Grammatopoulos G Wilkin G Beaulé PE
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Our understanding of pre-arthritic hip disease has evolved tremendously but challenges remain in categorizing diagnosis, which ultimately impacts choice of treatments and clinical outcomes. This study aims to report patient reported outcome measures (PROMs) comparing four different condition groups within hip preservation surgery by a group of fellowship-trained surgeons.

From 2018 to 2021, 380 patients underwent hip preservation surgery at our center and were classified into five condition groups: dysplasia: 82 (21.6%), femoro-acetabular impingement (FAI): 173 (45.4%), isolated labral tear: 103 (27.1%), failed hip preservation: 20 (5.3%) and history of childhood disease/other: 2 (0.5%). International hip outcomes Tool 12 (IHOT-12), numeric pain score and patient-reported outcomes measurement information system (PROMIS) were collected pre-operatively and at 3 months and 1 year post-operatively, with 94% and 82% follow-up rate respectively.

Arthroscopy (75.5%) was the most common procedure followed by peri-acetabular osteotomy (PAO) (22.4%) and surgical dislocation (2.1%). Re-operation rate were respectively 18.3% (15), 5.8% (10), 4.9% (5), 30% (6) and 0%. There were 36 re-operations in the cohort, 14 (39%) for unintended consequences of initial surgery, 10 (28%) for mal-correction leading to a repeat operation, 8 (22%) progression of arthritis, and 4 (11%) for incorrect initial diagnosis/intervention. Most common re-operations were hardware removal 31% (7 PAO, 3 surgical hip dislocation and 1 femoral de-rotational osteotomy), arthroscopy 31% (11) and arthroplasty 28% (10). All groups had significant improvements in their IHOT-12 as well as PROMIS physical and numerical pain scales, except those with failed hip preservation. Dysplasia group showed a slower recovery.

Overall, this study demonstrated a clear relation between the condition groups, their respective intervention and the significant improvements in PROMs with isolated labral pathology being a valid diagnosis. Establishing tertiary referral centers for hip preservation and longer follow-up is needed to monitor the overall survivorship of these various procedures.


Bone & Joint Open
Vol. 3, Issue 10 | Pages 804 - 814
13 Oct 2022
Grammatopoulos G Laboudie P Fischman D Ojaghi R Finless A Beaulé PE

Aims

The primary aim of this study was to determine the ten-year outcome following surgical treatment for femoroacetabular impingement (FAI). We assessed whether the evolution of practice from open to arthroscopic techniques influenced outcomes and tested whether any patient, radiological, or surgical factors were associated with outcome.

Methods

Prospectively collected data of a consecutive single-surgeon cohort, operated for FAI between January 2005 and January 2015, were retrospectively studied. The cohort comprised 393 hips (365 patients; 71% male (n = 278)), with a mean age of 34.5 years (SD 10.0). Over the study period, techniques evolved from open surgical dislocation (n = 94) to a combined arthroscopy-Hueter technique (HA + Hueter; n = 61) to a pure arthroscopic technique (HA; n = 238). Outcome measures of interest included modes of failures, complications, reoperation, and patient-reported outcome measures (PROMs). Demographic, radiological, and surgical factors were tested for possible association with outcome.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 11 - 11
1 Apr 2022
McGoldrick NP Cochran M Biniam B Bhullar R Beaulé PE Kim PR Gofton W Grammatopoulos G
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Short cementless femoral stems are increasingly popular as they allow for less dissection for insertion. Use of such stems with the anterior approach (AA) may be associated with considerable per-operative fracture risk. This study's primary aim was to evaluate whether patient-specific femoral- and pelvic- morphology and surgical technique, influence per-operative fracture risk. In doing so, we aimed to describe important anatomical thresholds alerting surgeons.

This is a single-centre, multi-surgeon retrospective, case-control matched study. Of 1145 primary THAs with a short, cementless stem inserted via the AA, 39 periprosthetic fractures (3.4%) were identified. These were matched for factors known to increase fracture risk (age, gender, BMI, side, Dorr classification, stem offset and indication for surgery) with 78 THAs that did not sustain a fracture. Radiographic analysis was performed using validated software to measure femoral- (canal flare index [CFI], morphological cortical index [MCI], calcar-calcar ratio [CCR]) and pelvic- (Ilium-ischial ratio [IIR], ilium overhang, and ASIS to greater trochanter distance) morphologies and surgical technique (% canal fill). Multivariate and Receiver-Operator Curve (ROC) analysis was performed to identify predictors of fracture.

Femoral factors that differed included CFI (3.7±0.6 vs 2.9±0.4, p<0.001) and CCR (0.5±0.1 vs 0.4±0.1, p=0.006). The mean IIR was higher in fracture cases (3.3±0.6 vs 3.0±0.5, p<0.001). % Canal fill was reduced in fracture cases (82.8±7.6 vs 86.7±6.8, p=0.007). Multivariate analysis and ROC analyses revealed a threshold CFI of 3.17 was predictive of fracture (sensitivity:84.6% / specificity:75.6%). Fracture risk was 29 times higher when patients had CFI>3.17 and II ratio>3 (OR:29.2 95%CI: 9.5–89.9, p<0.001).

Patient-specific anatomical parameters are important predictors of fracture-risk. When considering the use of short stems via the AA, careful radiographic analysis would help identify those at risk in order to consider alternative stem options.


Bone & Joint Research
Vol. 10, Issue 12 | Pages 780 - 789
1 Dec 2021
Eslam Pour A Lazennec JY Patel KP Anjaria MP Beaulé PE Schwarzkopf R

Aims

In computer simulations, the shape of the range of motion (ROM) of a stem with a cylindrical neck design will be a perfect cone. However, many modern stems have rectangular/oval-shaped necks. We hypothesized that the rectangular/oval stem neck will affect the shape of the ROM and the prosthetic impingement.

Methods

Total hip arthroplasty (THA) motion while standing and sitting was simulated using a MATLAB model (one stem with a cylindrical neck and one stem with a rectangular neck). The primary predictor was the geometry of the neck (cylindrical vs rectangular) and the main outcome was the shape of ROM based on the prosthetic impingement between the neck and the liner. The secondary outcome was the difference in the ROM provided by each neck geometry and the effect of the pelvic tilt on this ROM. Multiple regression was used to analyze the data.


The Bone & Joint Journal
Vol. 103-B, Issue 7 Supple B | Pages 46 - 52
1 Jul 2021
McGoldrick NP Fischman D Nicol GM Kreviazuk C Grammatopoulos G Beaulé PE

Aims

The aim of this study was to radiologically evaluate the quality of cement mantle and alignment achieved with a polished tapered cemented femoral stem inserted through the anterior approach and compared with the posterior approach.

Methods

A comparative retrospective study of 115 consecutive hybrid total hip arthroplasties or cemented hemiarthroplasties in 110 patients, performed through anterior (n = 58) or posterior approach (n = 57) using a collarless polished taper-slip femoral stem, was conducted. Cement mantle quality and thickness were assessed in both planes. Radiological outcomes were compared between groups.


Bone & Joint Research
Vol. 9, Issue 5 | Pages 242 - 249
1 May 2020
Bali K Smit K Ibrahim M Poitras S Wilkin G Galmiche R Belzile E Beaulé PE

Aims

The aim of the current study was to assess the reliability of the Ottawa classification for symptomatic acetabular dysplasia.

Methods

In all, 134 consecutive hips that underwent periacetabular osteotomy were categorized using a validated software (Hip2Norm) into four categories of normal, lateral/global, anterior, or posterior. A total of 74 cases were selected for reliability analysis, and these included 44 dysplastic and 30 normal hips. A group of six blinded fellowship-trained raters, provided with the classification system, looked at these radiographs at two separate timepoints to classify the hips using standard radiological measurements. Thereafter, a consensus meeting was held where a modified flow diagram was devised, before a third reading by four raters using a separate set of 74 radiographs took place.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_12 | Pages 54 - 54
1 Oct 2019
Lamontagne M Catelli DS Beaulé PE
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Osteochondroplasty procedure for cam deformity provides excellent outcomes on alleviating pain, improving quality of life and clinical function in femoroacetabular impingement syndrome (FAIS) patients. Although medium-term outcomes on gait biomechanics have been reported, it is unclear how it would translate to better hip muscle forces and joint loading in high range of motion tasks. The purpose of this study was to compare the muscle forces and hip joint contact forces (HCF) during a squat task in individuals before and after cam-FAIS surgical correction. Ten cam-FAIS patients prior and 2-years after osteochondroplasty, and 10 BMI- age- and sex-matched healthy control participants (CTRL) underwent 3D motion and ground reaction forces capture while performing a deep squatting task. Muscle and HCF were estimated using musculoskeletal modeling and comparisons were done using statistical parametric mapping (SPM).

Postoperatives squatted down with a higher anterior pelvic tilt and higher hip flexion compared with the preoperatives. Preoperative semimembranosus generated lower forces than the two other groups on the squat ascending, with no differences detected between post-ops and CTRLs. Preoperatives also showed reduced forces for the distal, ischial and medial portions of the adductor magnus relative to the CTRLs, which although reduced, still presented differences postoperatively. Preoperative anterior and medial contact forces were significantly lower than the CTRL group during both phases of the squat. Postoperative vertical and medial forces were also lower compared to the CTRLs. However, with higher vertical forces during the ascent phase of the squat compared to the preoperative, the postoperative group, significantly increased its HCF magnitude. A higher anterior pelvic tilt was associated with an innate restoration of the pelvis position, once the cam deformity no longer existed. The increased force of the semimembranosus muscle while ascending the squat generated higher vertical HCF, which also influenced the increased HCF total magnitude.

For any tables or figures, please contact the authors directly.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_12 | Pages 65 - 65
1 Oct 2019
Beaulé PE Slullitel PA Dobransky J Kreviazuk C Kim JK Grammatopoulos G
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Introduction

Porous coated cups have a low modulus of elasticity that enhances press-fit and a surface that promotes osseointegration as well as permitting modularity. Monoblock ceramic acetabular cups represent a subtype of uncemented cup permitting the use of large femoral heads. The aim of this study was to compare the short-term clinical and radiographic performances of both cups.

Methods

This was a prospective RCT of 86 unilateral THA patients (M: 40, F: 48; mean age: 59.5 ± 10.6) randomized to either a porous-coated, modular metal-on-polyethylene (MoP) acetabular component (pore size 250µm, 45% mean volume porosity)(n=46) or a hydroxyapatite (HA) and titanium-coated monoblock shell with ceramic-on-ceramic(CoC) bearing (pore size 300µm, 48% mean volume porosity & 80nm HA coating thickness)(n=42). All sockets were under-reamed by 1 mm. Two-year radiographs and patient-reported outcomes (PROMs) were available.


The Bone & Joint Journal
Vol. 101-B, Issue 8 | Pages 902 - 909
1 Aug 2019
Innmann MM Merle C Gotterbarm T Ewerbeck V Beaulé PE Grammatopoulos G

Aims

This study of patients with osteoarthritis (OA) of the hip aimed to: 1) characterize the contribution of the hip, spinopelvic complex, and lumbar spine when moving from the standing to the sitting position; 2) assess whether abnormal spinopelvic mobility is associated with worse symptoms; and 3) identify whether spinopelvic mobility can be predicted from static anatomical radiological parameters.

Patients and Methods

A total of 122 patients with end-stage OA of the hip awaiting total hip arthroplasty (THA) were prospectively studied. Patient-reported outcome measures (PROMs; Oxford Hip Score, Oswestry Disability Index, and Veterans RAND 12-Item Health Survey Score) and clinical data were collected. Sagittal spinopelvic mobility was calculated as the change from the standing to sitting position using the lumbar lordosis angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic-femoral angle (PFA), and acetabular anteinclination (AI) from lateral radiographs. The interaction of the different parameters was assessed. PROMs were compared between patients with normal spinopelvic mobility (10° ≤ ∆PT ≤ 30°) or abnormal spinopelvic mobility (stiff: ∆PT < ± 10°; hypermobile: ∆PT > ± 30°). Multiple regression and receiver operating characteristic (ROC) curve analyses were used to test for possible predictors of spinopelvic mobility.


The Bone & Joint Journal
Vol. 101-B, Issue 5 | Pages 540 - 546
1 May 2019
Juneau D Grammatopoulos G Alzahrani A Thornhill R Inacio JR Dick A Vogel KI Dobransky J Beaulé PE Dwivedi G

Aims

Cardiac magnetic resonance (CMR) was used to assess whether cardiac function or tissue composition was affected in patients with well-functioning metal-on-metal hip resurfacing arthroplasties (MoMHRA) when compared with a group of controls, and to assess if metal ion levels correlated with any of the functional or structural parameters studied.

Patients and Methods

In all, 30 participants with no significant cardiac history were enrolled: 20 patients with well-functioning MoMHRA at mean follow-up of 8.3 years post-procedure (ten unilateral, ten bilateral; 17 men, three women) and a case-matched control group of ten non-MoM total hip arthroplasty patients (six men, four women). The mean age of the whole cohort (study group and controls) at the time of surgery was 50.6 years (41.0 to 64.0). Serum levels of cobalt and chromium were measured, and all patients underwent CMR imaging, including cine, T2* measurements, T1 and T2 mapping, late gadolinium enhancement, and strain measurements.


The Bone & Joint Journal
Vol. 100-B, Issue 10 | Pages 1280 - 1288
1 Oct 2018
Grammatopoulos G Gofton W Cochran M Dobransky J Carli A Abdelbary H Gill HS Beaulé PE

Aims

This study aims to: determine the difference in pelvic position that occurs between surgery and radiographic, supine, postoperative assessment; examine how the difference in pelvic position influences subsequent component orientation; and establish whether differences in pelvic position, and thereafter component orientation, exist between total hip arthroplasties (THAs) performed in the supine versus the lateral decubitus positions.

Patients and Methods

The intra- and postoperative anteroposterior pelvic radiographs of 321 THAs were included; 167 were performed with the patient supine using the anterior approach and 154 were performed with the patient in the lateral decubitus using the posterior approach. The inclination and anteversion of the acetabular component was measured and the difference (Δ) between the intra- and postoperative radiographs was determined. The target zone was inclination/anteversion of 40°/20° (± 10°). Changes in the tilt, rotation, and obliquity of the pelvis on the intra- and postoperative radiographs were calculated from Δinclination/anteversion using the Levenberg–Marquardt algorithm.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_13 | Pages 1 - 1
1 Oct 2018
Bali K Ibrahim MM Smit K Poitras S Wilkin GP Beaulé PE
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Background

Hip dysplasia has traditionally been classified based on the lateral center edge angle (LCEA). A recent meta-analysis demonstrated no definite consensus and a significant heterogeneity in LCEA values used in various studies to define hip dysplasia and borderline dysplasia. To overcome the shortcomings of classifying hip dysplasia based on just LCEA, a comprehensive classification for adult acetabular dysplasia (CCAD) was proposed to classify symptomatic hips into three discrete prototypical patterns of hip instability; lateral/global, anterior, or posterior. The purpose of this study was to assess the reliability of this recently published CCAD.

Methods

One hundred thirty-four consecutive hips that underwent a PAO were categorized using a validated software (Hip2Norm) into four categories of normal, lateral/global, anterior or posterior. Based on the prevalence of individual dysplasia and using KappaSize R package version 1.1, seventy-four cases were necessary for reliability analysis: 44 dysplastic and 30 normal hips were randomly selected. Five surgeons (3 fellowship trained in hip preservation) did a first reading (Time 1) to classify the hips, followed by four raters for a second reading (Time 2) minimum two weeks apart. Thereafter, a consensus meeting was held where a simplified flow diagram was devised before a third reading by four raters using a separate set of 74 radiographs took place.


The Bone & Joint Journal
Vol. 100-B, Issue 7 | Pages 831 - 838
1 Jul 2018
Ibrahim MM Poitras S Bunting AC Sandoval E Beaulé PE

Aims

What represents clinically significant acetabular undercoverage in patients with symptomatic cam-type femoroacetabular impingement (FAI) remains controversial. The aim of this study was to examine the influence of the degree of acetabular coverage on the functional outcome of patients treated arthroscopically for cam-type FAI.

Patients and Methods

Between October 2005 and June 2016, 88 patients (97 hips) underwent arthroscopic cam resection and concomitant labral debridement and/or refixation. There were 57 male and 31 female patients with a mean age of 31.0 years (17.0 to 48.5) and a mean body mass index (BMI) of 25.4 kg/m2 (18.9 to 34.9). We used the Hip2Norm, an object-oriented-platform program, to perform 3D analysis of hip joint morphology using 2D anteroposterior pelvic radiographs. The lateral centre-edge angle, anterior coverage, posterior coverage, total femoral coverage, and alpha angle were measured for each hip. The presence or absence of crossover sign, posterior wall sign, and the value of acetabular retroversion index were identified automatically by Hip2Norm. Patient-reported outcome scores were collected preoperatively and at final follow-up with the Hip Disability and Osteoarthritis Outcome Score (HOOS).


The Bone & Joint Journal
Vol. 99-B, Issue 3 | Pages 303 - 309
1 Mar 2017
Beaulé PE Bleeker H Singh A Dobransky J

Aims

Joint-preserving surgery of the hip (JPSH) has evolved considerably and now includes a number of procedures, including arthroscopy, surgical dislocation, and redirectional osteotomies of the femur and acetabulum. There are a number of different factors which lead to failure of JPSH. Consequently, it is of interest to assess the various modes of failure in order to continue to identify best practice and the indications for these procedures.

Patients and Methods

Using a retrospective observational study design, we reviewed 1013 patients who had undergone JPSH by a single surgeon between 2005 and 2015. There were 509 men and 504 women with a mean age of 39 years (16 to 78). Of the 1013 operations, 783 were arthroscopies, 122 surgical dislocations, and 108 peri-acetabular osteotomies (PAO). We analysed the overall failure rates and modes of failure. Re-operations were categorised into four groups: Mode 1 was arthritis progression or organ failure leading to total hip arthroplasty (THA); Mode 2 was an Incorrect diagnosis/procedure; Mode 3 resulted from malcorrection of femur (type A), acetabulum (type B), or labrum (type C) and Mode 4 resulted from an unintended consequence of the initial surgical intervention.


The Bone & Joint Journal
Vol. 98-B, Issue 6 | Pages 799 - 805
1 Jun 2016
McIsaac DI Beaulé PE Bryson GL Van Walraven C

Aims

Total joint arthroplasty (TJA) is commonly performed in elderly patients. Frailty, an aggregate expression of vulnerability, becomes increasingly common with advanced age, and independently predicts adverse outcomes and the use of resources after a variety of non-cardiac surgical procedures. Our aim was to assess the impact of frailty on outcomes after TJA.

Patients and Methods

We analysed the impact of pre-operative frailty on death and the use of resources after elective TJA in a population-based cohort study using linked administrative data from Ontario, Canada.


The Bone & Joint Journal
Vol. 98-B, Issue 6 | Pages 730 - 735
1 Jun 2016
Bsat S Frei H Beaulé PE

The acetabular labrum is a soft-tissue structure which lines the acetabular rim of the hip joint. Its role in hip joint biomechanics and joint health has been of particular interest over the past decade. In normal hip joint biomechanics, the labrum is crucial in retaining a layer of pressurised intra-articular fluid for joint lubrication and load support/distribution. Its seal around the femoral head is further regarded as a contributing to hip stability through its suction effect. The labrum itself is also important in increasing contact area thereby reducing contact stress. Given the labrum’s role in normal hip joint biomechanics, surgical techniques for managing labral damage are continuously evolving as our understanding of its anatomy and function continue to progress. The current paper aims to review the anatomy and biomechanical function of the labrum and how they are affected by differing surgical techniques.

Take home message: The acetabular labrum plays a critical role in hip function and maintaining and restoring its function during surgical intervention remain an essential goal.

Cite this article: Bone Joint J 2016;98-B:730–5.


The Bone & Joint Journal
Vol. 97-B, Issue 12 | Pages 1608 - 1614
1 Dec 2015
Tice A Kim P Dinh† L Ryu JJ Beaulé PE

The primary purpose of this study of metal-on-metal (MoM) hip resurfacing was to compare the effect of using a cementless or cemented femoral component on the subsequent bone mineral density (BMD) of the femoral neck.

This was a single-centre, prospective, double-blinded control trial which randomised 120 patients (105 men and 15 women) with a mean age of 49.4 years (21 to 68) to receive either a cemented or cementless femoral component. Follow-up was to two years. Outcome measures included total and six-point region-of-interest BMD of the femoral neck, radiological measurements of acetabular inclination, neck-shaft and stem-shaft angles, and functional outcome scores including the Harris hip score, the Western Ontario and McMaster Universities Osteoarthritis Index and the University of California at Los Angeles activity scale.

In total, 17 patients were lost to follow-up leaving 103 patients at two years. There were no revisions in the cementless group and three revisions (5%) in the cemented group (two because of hip pain and one for pseudotumour).

The total BMD was significantly higher in the cementless group at six months (p < 0.001) and one year (p = 0.01) than in the cemented group, although there was a loss of statistical significance in the difference at two years (p = 0.155).

All patient outcomes improved significantly: there were no significant differences between the two groups.

The results show better preservation of femoral neck BMD with a cementless femoral component after two years of follow-up. Further investigation is needed to establish whether this translates into improved survivorship.

Cite this article: Bone Joint J 2015;97-B:1608–14.


Bone & Joint Research
Vol. 2, Issue 8 | Pages 140 - 148
1 Aug 2013
Gauthier L Dinh L Beaulé PE

Objectives

To quantify and compare peri-acetabular bone mineral density (BMD) between a monoblock acetabular component using a metal-on-metal (MoM) bearing and a modular titanium shell with a polyethylene (PE) insert. The secondary outcome was to measure patient-reported clinical function.

Methods

A total of 50 patients (25 per group) were randomised to MoM or metal-on-polyethlene (MoP). There were 27 women (11 MoM) and 23 men (14 MoM) with a mean age of 61.6 years (47.7 to 73.2). Measurements of peri-prosthetic acetabular and contralateral hip (covariate) BMD were performed at baseline and at one and two years’ follow-up. The Western Ontario and McMaster Universities osteoarthritis index (WOMAC), University of California, Los Angeles (UCLA) activity score, Harris hip score, and RAND-36 were also completed at these intervals.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 177 - 177
1 Sep 2012
Carsen S Beaulé PE Willis B Ward L Rakhra K Dunlap H Moroz P
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Purpose

The importance of femoral head-neck morphology in the development of early hip osteoarthritis is recognized in femeroacetabular impingement (FAI), however no studies have examined FAI morphology in the developing hip, i.e. pre-closure of the proximal femoral physis. We developed a pilot project to study prevalence of CAM-type FAI hip morphology in both the pre- and post-closure proximal femoral physes of asymptomatic children using MR-imaging. We also examined biologic markers possibly related to FAI etiology, including Vitamin D metabolites, BMI, family history, and activity levels.

Method

Recruitment included volunteers with asymptomatic lower extremities, and either pre- or post-closure of the proximal femoral physis. Males were 10–12 years (pre-closure) or 15–18 years (post-closure); females were 8–10 years or 14 18 years. Phlebotomy and urine sampling were used to assess metabolic markers. MRI of bilateral hips and a clinical exam including hip impingement tests were conducted. MR imaging assessment was independent and blinded and recorded using established parameters including alpha angles measured at both the 3:00 (anterior head-neck junction) and 1:30 (antero-superior head-neck junction) radial image positions.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 165 - 165
1 Sep 2012
Powell JN Beaulé PE Antoniou J Bourne RB Schemitsch EH Vendittoli P Smith F Werle J Lavoie G Burnell C Belzile É Kim P Lavigne M Huk OL O'Connor G Smit A
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Purpose

The purpose of the study was to determine the rate of conversion from RSA to THR in a number of Canadian centers performing resurfacings

Method

Retrospective review was undertaken in 12 Canadian Centers to determine the rate of revision and reason for conversion from RSA to THR. Averages and cross-tabulation with Chi-Squared analysis was performed. kaplan Meier survivorship was calculated.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 41 - 41
1 Sep 2012
Beaulé PE Speirs AD Sylvester SE Nishiwaki T Hamdi A
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Purpose

Primary uncemented total hip arthroplasty is the fixation of choice for most patients undergoing hip replacement in North America. Initial stem stability will be detected by the fit and fill of the implant to the bone as well as the overall stem geometry as it relates to its mechanical stability. This study aims to determine the geometric and structural parameters of common cementless tapered femoral stems to better understand their early clinical performance with respect to bony fixation.

Method

Templates for six proximally coated tapered uncemented femoral stems: Accolade (Stryker), Profemur (Wright), Taperloc (Biomet), M/L Taper (Zimmer), Anthology (Smith-Nephew) and Trilock (Depuy) were scanned and saved as images on a PC. Stem sizes were assigned according to AP plane width measurements taken at the most lateral implant shoulder, and images analyzed using ImageJ (US National Institutes of Health). Measurements were made of stem length, and at various locations, the width and thickness of the stem. Coronal plane stiffness was calculated according to beam theory, assuming an elastic modulus of 114 GPa for the Profemur, Taperloc M/L Taper, Anthology and Trilock stems. The Accolade stem has a modulus of 85.5 GPa. due to TMZF alloy which is 25% more flexible. Stem thickness and taper ratios were calculated as a measure of lateral vs. AP fill of the femur. All measurements were plotted as manufacturer-specific curves relative to stem width.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 159 - 159
1 Sep 2012
Beaulé PE Dinh L Gauthier L Kim PR Feibel RJ Thurston PR Giachino AA
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Purpose

Use of a large femoral head metal-on-metal bearing in total hip arthroplasty may offer an advantage in terms of dislocation rates and more natural joint kinematics. The acetabular component is more rigid however in these prostheses and if not placed accurately can lead to increased levels of metal ion release. A prospective randomized controlled trial was conducted to quantify bone mineral density on the acetabular side, as well as compare metal ion levels from a standard metal-on-polyethylene bearing to a large head metal-on-metal bearing in primary total hip arthroplasty.

Method

Fifty patients were randomized to receive total hip arthroplasty with either the CONSERVE A-Class Total Hip with BFH femoral head or the Lineage acetabular component with polyethylene insert and cobalt chrome femoral head. There were 27 females (11 BFH) and 23 males (14 BFH), with a mean overall age of 61.6 (range 47.7–73.2). Serum levels of cobalt, chromium, and titanium were measured at regular intervals up to two years. Harris Hip Score, WOMAC, UCLA, and RAND-36 were completed at these same intervals. Standard radiographs as well as periprosthetic BMD were performed.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 108 - 108
1 Sep 2012
March GM Elfatori S Beaulé PE
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Purpose

Transfusion rates after primary total hip has been reported up to 39.2%. The purpose of our study was to evaluate the efficacy of TXA in minimizing risk of allogeneic blood transfusion after primary total hip and hip resurfacing arthroplasty.

Method

Retrospective data on a cohort of 88 patients undergoing total hip arthroplasty and 44 who undergoing hip resurfacing arthroplasty who received a single pre-operative bolus of 1g TXA was compared with a control group matched for starting haemoglobin (Hg), body mass index (BMI), age, gender, blood loss, surgical time, and surgeon. All procedures were completed at a single institution with standardized post-operative care. Endpoints included allogeneic blood transfusion rate, post operative day one Hg, and overall Hg decrease.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 9 | Pages 1187 - 1192
1 Sep 2012
Rakhra KS Lattanzio P Cárdenas-Blanco A Cameron IG Beaulé PE

Advanced MRI cartilage imaging such as T1-rho (T1ρ) for the diagnosis of early cartilage degradation prior to morpholgic radiological changes may provide prognostic information in the management of joint disease. This study aimed first to determine the normal T1ρ profile of cartilage within the hip, and secondly to identify any differences in T1ρ profile between the normal and symptomatic femoroacetabular impingement (FAI) hip. Ten patients with cam-type FAI (seven male and three female, mean age 35.9 years (28 to 48)) and ten control patients (four male and six female, mean age 30.6 years (22 to 35)) underwent 1.5T T1ρ MRI of a single hip. Mean T1ρ relaxation times for full thickness and each of the three equal cartilage thickness layers were calculated and compared between the groups. The mean T1ρ relaxation times for full cartilage thickness of control and FAI hips were similar (37.17 ms (sd 9.95) and 36.71 ms (sd 6.72), respectively). The control group demonstrated a T1ρ value trend, increasing from deep to superficial cartilage layers, with the middle third having significantly greater T1ρ relaxation values than the deepest third (p = 0.008). The FAI group demonstrated loss of this trend. The deepest third in the FAI group demonstrated greater T1ρ relaxation values than controls (p = 0.028).

These results suggest that 1.5T T1ρ MRI can detect acetabular hyaline cartilage changes in patients with FAI.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_VIII | Pages 48 - 48
1 Mar 2012
Beaulé PE
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The renewed interest in the clinically proven low wear of the metal-on-metal bearing combined with the capacity of inserting a thin walled cementless acetabular component has fostered the reintroduction of hip resurfacing. As in other forms of conservative hip surgery, i.e. pelvic osteotomies and impingement surgery, patient selection will help minimize complications and the need for early reoperation.

Patient Selection and Hip Resurfacing

Although hip resurfacing was initially plagued with high failure rates, the introduction of metal on metal bearings as well as hybrid fixation has shown excellent survivorships of 97 to 99% at 4 to 5 years follow-up. However, it is important to critically look at the initial published results. In all of these series there was some form of patient selection. For example, in the Daniel and associates publications, only patients with osteoarthritis with an age less than 55 were included with 79% of patients being male. Treacy and associates stated that: “the operation was offered to men under the age of 65 years and women under the age of 60 years, with normal bone stock judged by plain radiographs and an expectation that they would return to an active lifestyle, including some sports”. However in the materials and methods, although the mean age is 52 years, the range is from 17 to 76 years including some patients with rheumatoid arthritis as well as osteonecrosis. Obviously, some form of patient selection is needed; but how one integrates them is where the Surface Arthroplasty Risk Index (SARI) is useful. With a maximum score of 6, points are assigned accordingly: femoral head cyst >1cm: 2 points; patient weight <82kg: 2 points; previous hip surgery: 1 point; UCLA Activity level >6: 1 point.

A SARI score >3 represented a 4 fold increase risk in early failure or adverse radiological changes and with a survivorship of 89% at four years. The SARI index also proved to be relevant in assessing the outcome of the all cemented McMinn resurfacing implant (Corin¯, Circentester, England) at a mean follow-up of 8.7 years. Hips which had failed or with evidence of radiographic failure on the femoral side had a significantly higher SARI score than the remaining hips, 3.9 versus 1.9. Finally, one must consider the underlying diagnosis when evaluating a patient for hip resurfacing. In cases of dysplasia, acetabular deficiencies combined with the inability of inserting screws through the acetabular component may make initial implant stability unpredictable. This deformity in combination with a significant leg length discrepancy or valgus femoral neck could compromise the functional results of surface arthroplasty, and in those situations a stem type total hip replacement may provide a superior functional outcome. In respect to other diagnoses (osteonecrosis, inflammatory arthritis), initial analyses have not demonstrated any particular diagnostic group at greater risk of earlier failure. The only reservation we have is in patients with compromised renal function since metal ions generated from the metal-on-metal bearing are excreted through the urine and the lack of clearance of these ions may lead to excessive levels in the blood.

Surgical Technique

Because resurfacing has not been within the training curriculum of orthopaedic surgeons for the last 2 decades, there will most likely be a learning curve in the integration of this implant within clinical practice. This data was confirmed for hip resurfacing when looking at the Canadian Academic Experience where in the first 50 cases of five arthroplasty surgeons only a 3.2% failure rate was noted of which 1.6% were due to neck fracture. Femoral neck fracture can occur because of significant varus positioning as well as osteonecrosis of the femoral head due to either disruption of the blood supply or over cement penetration. Finally, abnormal wear patterns leading to severe soft tissue reactions are being increasingly recognized and are related to either impingement or vertically placed acetabular components. Although impingement has long been recognized after total hip arthroplasty to limit range of motion and in extreme cases to hip instability, the risk after hip resurfacing may be greater since the femoral head-neck unit is preserved. Beaulé and associates have reported that 56% of hips treated by hip resurfacing have an abnormal offset ratio pre-operatively, with the two main diagnostic groups presenting deficient head-neck offset being osteonecrosis and osteoarthritis both of which have been associated with femoroacetabular impingement in the pre arthritic state.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_VIII | Pages 41 - 41
1 Mar 2012
Beaulé PE
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Femoral neck fractures remain the leading cause of early failure after metal-on-metal hip resurfacing. Although its' exact pathomechanism has yet to be fully elucidated, current retrieval analysis has shown that either an osteonecrotic event and/or significant surgical trauma to the femoral head neck junction are the leading causes. It is most likely that no single factor like patient selection and/or femoral component orientation can fully avoid their occurrence. As in osteonecrosis of the native hip joint, a certain cell injury threshold may have to be reached in order for femoral neck fracture to occur. These insults are not limited to the surgical approach, but also include femoral head preparation, neck notching, and cement penetration.

Although some have argued that the posterior approach does not represent an increased risk fracture for ON after hip resurfacing because of the so-called intraosseous blood supply to the femoral head, to date, the current body of literature on femoral head blood flow in the presence of arthritis has confirmed the critical role of the extraosseous blood supply from the ascending branch of the medial circumflex, as well as the lack of any substantial intraosseous blood supply. Conversely, anterior hip dislocation of both the native hip joint as well as the arthritic hip preserves femoral head vascularity. The blood supply can be compromised by either sacrificing the main branch of the ascending medial femoral circumflex artery or damaging the retinacular vessels at the femoral head-neck junction. Thus an approach which preserves head vascularity, while minimizing soft tissue disruption would certainly be favorable for hip resurfacing. This presentation will review the current state of knowledge on vascularity of the femoral head as well as surgical techniques enhancing its preservation.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 567 - 567
1 Nov 2011
Beaulé PE Smith F Powell JN Antoniou J Bourne RB Lavigne M Belzile E Schemitsch EH Garbuz D
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Purpose: Recently, there has been concern raised on the occurrence of pseudotumors after metal on metal hip resurfacing. A pseudotumor is defined as a local soft tissue mass associated with localized bony and/or tissue (muscle) destruction. The primary purpose of this study is to determine the incidence of this complication in several high volume Canadian academic centres.

Method: Nine of the 11 Canadian academic centres who perform metal on metal hip resurfacings were surveyed. The number of metal on metal hip resurfacing arthroplasties performed at each centre was first determined, as were the number of those who have presented with a pseudotumour, and subsequently gone on to revision surgery. The basic demographics of the group were recorded, as were the radiographic and implant design variables for those cases presenting with a pseudotumour.

Results: A sample of 3,400 hip resurfacing arthroplasties performed between 2002 and December 2008 were surveyed. Demographics were tabulated for a sub-sample of these patients. 76% were male, the mean length of follow-up was 3.02 years, mean BMI was 28.65, and mean age was 52.10 years. Three of 3,400 cases presented with a pseudotumour, an incidence of .09%.

Conclusion: Although pseudotumors remain a concern after metal on metal hip resurfacing, the incidence at short to mid term follow-up is very low in this multi-centre academic survey. This information is significantly lower than what other groups have recently reported. Continued close monitoring is required in order to determine what clinical factors are at play.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 561 - 561
1 Nov 2011
Beaulé PE Poitras S Dervin GF
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Purpose: The Quality of Recovery-40 questionnaire (QoR-40) has been developed, validated and extensively used to assess the quality of life of patients following major surgery. It is composed of 40 questions answered by the patient and organized into six dimensions: emotional state, physical comfort, psychological support, physical independence, pain, and global score. However, this questionnaire has not been validated in an orthopaedic population. The objective of the study was to assess the psychometric properties of the QoR-40 in a population of patients undergoing total knee or hip arthroplasty.

Method: Sixty seven patients undergoing total knee arthroplasty and 65 patients undergoing total hip arthroplasty were recruited. Patients were assessed with the QoR-40 and the SF-12, a validated generic quality of life questionnaire, at the following seven times: three and one week pre-operative; one, two and three days post-operative (short-term); one and three months post-operative (long-term). The following psychometric properties of the QoR-40 were assessed: reliability between three and one week pre-operative using intra-class correlation coefficients (ICC), construct validity with the SF-12 using Pearson product moment correlations, responsiveness to change using effect sizes, floor and ceiling effects, and predictive validity of short-term QoR-40 scores of long-term SF-12 scores.

Results: All dimensions and global scores of the QoR-40 appeared reliable, with ICCs’ ranging from 0.75 to 0.84. For construct validity, physical dimension scores of the QoR-40 (physical comfort, physical independence, pain) were weakly or not significantly related to the physical component scale of the SF-12 (−0.09 to 0.34), except for long-term where the correlations were moderate (0.35 to 0.62). The emotional state score of the QoR-40 was moderately to substantially related to the mental component scale of the SF-12 for all periods (0.40 to 0.78). Effect sizes were higher for the QoR-40 when compared to the SF-12 in the intervals of the first month, while they were higher for the SF-12 in the intervals above one month. The QoR-40 demonstrated ceiling effects for the physical independence dimension pre-operatively and three months post-operatively, and for all periods for the psychological support dimension. As for predictive validity, short-term post-operative QoR-40 scores were weakly or not significantly predictive of long-term postoperative SF-12 scores (0.01 to 0.41).

Conclusion: The QoR-40 appears to be a reliable tool assessing a quality of life construct different from the SF-12 and more responsive to change during the short-term follow-up to surgery. The QoR-40 could be used to assess short-term quality of life following surgery. The QoR-40 should not be used to predict long-term quality of life. To further improve the tool, the psychological support dimension of the QoR-40 should be reconceptualized because of ceiling effects.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 555 - 555
1 Nov 2011
White C Castellaro JL Beaulé PE Kim P
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Purpose: Although femoral neck fractures remain a concern in terms of short term failures for hip resurfacing, acetabular component position and fixation are increasingly being recognized as causes of mid term failures for hip resurfacing. The purpose of our study was to evaluate the migration pattern of a cementless acetabular component for a metal on metal hip resurfacing.

Method: Between January 2006 and June 2007, 130 patients underwent metal on metal hip resurfacing; 66 hips in 60 patients were included in this analysis. Forty-eight patients were male and 12 were female, with a mean age of 50 (range, 32–66). Ninety-five percent of the surgeries were performed for osteoarthritis. All surgeries were performed by two surgeons using the Conserve Plus (Wright Medical Technology, Memphis, TN) hip resurfacing system. The acetabular component is a monoblock cobalt chrome with a porous beaded surface for osteointegration. In all cases acetabular migration was measured both vertically and horizontally, on serial radiographs using the computer-assisted Ein Bild Röntgen Analyse (EBRA) method. A minimum of three comparable radiographs is necessary for calculating the migration curves. We scored medial migration as negative horizontal movement.

Results: At a mean follow up 25.3 months (range, 24–36 months), each hip had an average of 5.1 radiographs for analysis. The software excluded two cases for poor comparability ending finally with 64 cases for the analysis. Eighty-seven point five per cent of the cups showed less than 1 mm migration in the medium-lateral axis and 54.7% less than 1 mm in the vertical axis. Seventy-seven percent of the cups showed a combined migration of less than 2 mm in the observation period, without radiolucencies, leaving 23% of the acetabular components with 2 mm or greater of component migration. One of these cases required revision for aseptic loosening at 34 months.

Conclusion: In our study the majority of the acetabular components were stable with some of the migration observed secondary to lack of complete initial seating due to the rigidity of the shell. Krismer et al did report on the migration of the PCA shell (also a porous beaded cobalt-chrome shell) using EBRA, with 27.5% of the shells demonstrating > 1 mm of migration. Although hip resurfacing has only mid term followup, results have been good to excellent. Caution should still be maintained since the higher frictional torque generated by the larger femoral head size as well as the nanometer size particles could negatively affect long term fixation of the acetabular component.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 575 - 575
1 Nov 2011
Beaulé PE Banga K
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Purpose: The surgical correction of FAI deformity is a well accepted treatment in patients presenting with hip pain with associated labral-chondral damage. The anterior approach with assisted hip arthroscopy provides access to the anterior head-neck junction with potentially quicker recovery for patients. The purpose of this study is to present the safety and efficacy of this approach in performing impingement surgery.

Method: Forty-eight Hueter procedures were performed in 45 patients (13 males and 32 females). Mean age was 42.09 years (range, 21–65 years), and mean BMI was 24.31(range, 21–33). The scope was performed first to deal with intra-articular damage. All patients were diagnosed with CAM type FAI with labral pathology based on MRI arthrogram with an alpha angle > 50.5 degrees.

Results: At a mean follow-up of 21.8 months (range 12–30 months), Harris Hip scores improved from 64.66 (range, 42.0–93.0) to 79.97 (range, 47.0–96.0). There were 5 re-operations at a mean time of 15.2 months (range, 4–22). One had a repeat hip scope for intra-articular adhesions, and another for recurrent traumatic tear of the labrum. Three cases with residual hip dysplasia had corrective surgery with a peri-acetabular osteotomy at an average of 16.67 months (range, 15–18 months).

Conclusion: Overall, we have found this to be a reliable, safe and reproducible approach to the treatment of FAI. This is a day care procedure as compared to the classic open procedure. Uncorrected hip dysplasia in the presence of a CAM deformity is a risk factor for early failure.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 560 - 560
1 Nov 2011
Varin D Speirs A Benoit D Beaulieu M Lamontagne M Beaulé PE
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Purpose: A functional centre of rotation (CoR) is often required in biomechanical analysis of the hip or as a landmark in computer guided surgery. It was previously shown that circumduction motions predict a CoR that is inferior and lateral to the geometric centre of the hip bearing surfaces. It is therefore necessary to establish the best method for determining the CoR to improve surgical planning. The objective of this study was to compare the predicted CoR from circumduction and star motions, and to compare these to the geometric centre of the joint.

Method: Eight cadaveric hips from four cadavers were tested. Prior to testing, CT scans of the cadavers were made from the iliac crest to the tibial plateau; the alpha angle for all hips was less than 50° so all hips were considered ‘normal’. Reflective marker arrays were rigidly mounted on the femoral diaphysis and iliac spine using 4mm Steinman pins. A five-camera Vicon system (Oxford, UK) was used to track the motions of the arrays during manipulation of the lower limb. To determine the functional hip centre, trials consisting of five cycles each of circumduction, flexion-extension and abduction-adduction were performed on each lower limb; three trials of each motion were performed. The range of motion was approximately 45° in the coronal and sagittal planes. For the ‘star’ motion, the flexion-extension and abduction-adduction trial data were combined. Following the trials the hip was dissected to expose the articular surfaces of the femoral head and acetabulum. These surfaces were traced using a pointer equipped with reflective markers to determine the geometric centre. To calculate the functional centre, the 3D coordinates of the markers were used to construct a local-to-global 3D transform for each frame throughout the trial. The geometric centre was calculated using a least-squares sphere fit (Gauss-Newton) of the trace data, calculated in the respective local coordinate systems. The coordinates of the functional centres were then transformed to an anatomic coordinate system, using the geometric centre as the origin. All calculations were performed using Matlab (Mathworks, Inc, MA, USA). A t-test was performed in each anatomic direction to detect differences in CoR predicted by the two motions.

Results: Both the circumduction and star motions resulted in a similar CoR. Differences were 0.41±2.25mm in the anterior-posterior direction; 0.09±0.72mm in the superior-inferior direction; and 0.21±0.82mm in the medial-lateral direction, none of which were significant (p> 0.5). The overall mean distance between the CoR predicted by the two motions was 2.0±1.3mm. The functional centre was also found to be lateral and inferior to the geometric centre, and was consistent for each motion. Results for the acetabulum showed similar trends.

Conclusion: This study has shown that circumduction and star motions are equivalent in predicting the hip functional CoR; differences were small compared to the dimensions involved in studies such as gait analyses. However, both motions predicted a CoR that was inferior and lateral to the spherical centre of the femoral head, suggesting that the hip does not act as a true ball-and-socket joint with congruent spherical bearing surfaces. This may have important consequences in studies at the scale of the hip joint, especially for pathological conditions such as femoroacetabular impingement.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 568 - 568
1 Nov 2011
Goulding K Beaulé PE
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Purpose: LFCN neuropraxia is a known complication of the anterior approach to the hip joint. The objective of this study was to define the incidence, functional impact and natural history of this neuropraxia in the anterior approach after both hip resurfacing (HR) and primary total hip arthroplasty (THA).

Method: Between September 2006 and January 2008, 132 consecutive patients underwent a direct anterior hip approach (DAA) (55 THR; 77 HR). Sixty-two patients were female and 70 were male; the mean age was 55.54 (range, 29.9 to 88.7). Self reported questionnaires for sensory deficits of LFCN, a neuropathic pain score (DN4) as well as SF-12, UCLA and WOMAC scores were completed. A subset of 60 patients (30 THA, 30 resurfacing) was evaluated at two time intervals (6 and 12 months).

Results: One hundred and seven patients (81%) reported LFCN neuropraxia, with a mean severity score of 2.32/10 (SD, 2.11); mean DN4 score of 2.42/10 (SD, 2.37). Hip resurfacing had a higher incidence of neuro-praxia compared to THA: 91% versus 67% (p=0.02), respectively. No functional limitations were reported on SF-12, WOMAC or UCLA scores. Of the subset of 60 patients, 53 (88.3%) reported neuropraxia at the six month follow-up interval with only three (5.7%) having complete resolution at 12 months. Patients who reported neuropraxia at both testing intervals did report an improvement in DN4 scores: 3.6 versus 2.5 at 6 and 12 months, respectively (p=0.02).

Conclusion: Although LFCN neuropraxia is a frequent complication after DAA total hip arthroplasty, it does not lead to any functional limitations. A decrease in symptoms does occur over time, with only a small number of patients reporting complete resolution.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 554 - 554
1 Nov 2011
Ng KG Rouhi G Lamontagne M Beaulé PE
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Purpose: Femoroacetabular impingement (FAI) is recognized as a pathomechanical process that leads to hip osteoarthritis (OA). Past research has been focused on treatments for FAI; however, few studies have been done to link FAI with the progression of OA. It is hypothesized that elevated mechanical stimuli could provoke bone remodeling in the subchondral bone and articulating surfaces due to cam FAI (aspherical head-neck deformity), which would accelerate the progression of OA. Using finite element analysis (FEA), the aim is to compare healthy hips to hips with cam FAI – investigating the mechanical stimuli effect of FAI towards OA.

Method: Net joint reaction forces were obtained from joint kinematics, kinetics, and by inverse dynamics calculation for a dynamic squat motion of a control subject and a cam FAI patient (both males with comparable age, BMI, and femur lengths). CT scans were acquired from both subjects. Data slices were compiled using 3D-DOCTOR (Able Software Corp, MA) to form a 3D model with slice thickness calibrated at 1.25mm in the superior-inferior axis. ANSYS (ANSYS, PA) software was used for FEA. The femur models were given quadrilateral shell elements and modeled as linear elastic orthotropic materials. The ground reaction forces were applied to the femur models, simulating dynamic loads, using boundary conditions specific to hip loading. Von Mises stresses were determined to examine stress concentrations and adverse loading conditions. Strain energy distributions were determined to examine the effect of stimuli on the initiation and rate of bone remodeling.

Results: At the maximum squat-depth, the FEA results demonstrated that the net forces acting on the FAI hip produced high mechanical stimuli regions around the head and neck. The highest stress concentration (590 MPa) was located at the anterosuperior head-neck junction, where cam FAI is most prominent. For the control hip, stresses were significantly lower (maximum of 151 MPa) and dissipated around the head. For both the FAI and the control hip, the maximum strain energy concentrations were seen at the superior portion of the head (4.725 kJ vs. 2.192 kJ for FAI vs. control hip respectively).

Conclusion: The increase in mechanical stimuli can be due to the loading configurations as well as to the abnormal geometry of the cam deformity. Assuming that the strain energy density (SED) and its rate is linearly proportional to the rate of bone turnover, based on a recent semi-mechanistic bone remodeling theory, a higher rate of bone turnover is expected in the FAI than in a normal hip. Depending on the level and rate of SED, the rate of bone remodeling will vary in order to provide a new homeostatic configuration. The next-step analysis, examining the mechanical stimuli in the acetabulum and its cartilage, is currently in progress. This would provide useful information about the possible locations of OA initiation and establish a link between FAI with cartilage degeneration.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 555 - 555
1 Nov 2011
Varin D Lamontagne M Beaulieu M Beaulé PE
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Purpose: It is thought that the anterior approach better restores gait mechanics after total hip arthroplasty (THA) being a pure intermuscular/internervous approach. The purpose of this study was to compare three-dimensional (3-D) kinematics and kinetics of THA patients that had an anterior (ANT) vs. a lateral (LAT) approach. It is hypothesized that the ANT group will exhibit fewer differences than the LAT group when compared to a control group (CON).

Method: Fifty-four participants were divided into three groups of 18: ANT (12 women, 6 men; age: 60.9 ± 6.2 yr; BMI: 28.8 ± 4.9 kg/m2), LAT (10 women, 8 men; age: 65.2 ± 6.3 yr; BMI: 27.5 ± 5.1 kg/m2) and CON (9 women, 9 men; age: 63.9 ± 4.4 yr; BMI: 25.4 ± 3.2 kg/ m2). All THA patients had primary unilateral THA due to osteoarthritis and had no other lower-limb pathology. They were evaluated five to 17 months after surgery. 3-D kinematics and kinetics were obtained using a nine-camera motion analysis system and a force platform placed on the first step of a staircase. Each participant performed three trials of stair ascending. A series of one-way ANOVAs were used to compare peak angles, range of motion (ROM), peak resultant joint forces as well as moments and powers of the hip, knee and ankle joints in all three planes.

Results: Most differences occurred during transitions between double- to single-legged stance. Both LAT and ANT groups ascended the staircase with a more abducted hip than the CON group, resulting in reduced hip abduction moment. This could be the result of the implant’s position and its potential abductor lever arm reduction. Both groups also showed reduced peak internal rotation moments. These results have previously been found in THA patients who have been operated through lateral and posterior approaches, and are thought to be caused by hip abductor muscle damage inherent to the surgical approach. However, only the LAT group had lower compression forces at the hip, knee and ankle joints compared to the CON group. This indicates that LAT group uses a strategy that reduces the loading on the operated leg, which may be due to the detachment of the anterior third of the gluteus medius. It could be speculated that the muscle sparing aspect of ANT approach allows patients to load adequately their operated leg, even if their frontal plane kinematics and kinetics are altered.

Conclusion: Some studies have failed to find differences with the anterior approach. However, they have only looked at spatiotemporal gait parameters. 3-D kinematics and kinetics can provide a more detailed assessment of function and detect more subtle differences. In this study, 3-D biomechanical analysis has detected differences in THA patients operated through different surgical approaches during stair ascent. The data obtained showed similar frontal plane kinematics for both groups, but different lower-limb compression forces. This study supports the use of the anterior approach for better restoration of function after total hip arthroplasty.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 568 - 568
1 Nov 2011
White C Carsen S Rasuli K Doucette S Beaulé PE
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Purpose: We aimed to measure the early migration pattern of a titanium alloy, tapered, plasma and hydroxyapatite coated femoral stem and any factors associated with subsidence.

Method: Between January 2005–June 2007, 387 Accolade cementless femoral stems (Stryker, Allendale NJ) were implanted at our institution. Seventy-seven had a minimum of two years post operative follow up and a complete set of pre and postoperative radiographs for analysis. Our group inlcuded 45 females with a mean age of 71.4 years, and 32 males with a mean age of 68.5 years. The primary diagnosis was degenerative osteoarthritis in 71 patients, avascular necrosis in two, and post fracture in four patients. The average BMI was 27.1. We measured the canal index to assess bone quality and the canal calcar index to assess the proximal femoral morphology. Immediate postoperative radiographs were assessed for canal fill of the prosthesis and implantation varus/valgus angles. The EBRA-FCA software was used to obtain migration curves for each stem. Best fit curve of subsidence over time was calculated and the data was analysed using a Kaplan Meier survivorship with 1.5 mm of subsidence as an endpoint. We then performed a multivariate and univariate regression analysis for predictors of subsidence.

Results: The mean follow up was 29.3months (24–48). The mean canal index was 0.55 (0.36–0.68) with a mean canal calcar index of 0.54 (0.39–0.79). The average canal fill index at the midpoint of the stem was 80 in 40 stems. A total of 414 radiographs were analysed for the EBRA measurements. Of these 21 (5%) were discarded by the software as they did not meet the criteria for comparability. This led to the exclusion of seven patients, leaving the final study group of 77. All remaining patients had a minimum of four radiographs with an average of 4.6 for analysis. The average subsidence at 24 months was 2 mm and this had risen to 2.4 mm by 36 months postoperatively. When analysed using a Kaplan Meier curve using 1.5 mm as an end point we found a survivorship of 63.4% (52.3–74.5) at 24 months and this had worsened to 41.6% (26.6–56.5) by 36 months. Multivariate and univariate regression analysis of measured variables did not reveal any significant hazard for any factor other than the larger stem sizes doing worse.

Conclusion: Although several cementless tapered stem designs have had an excellent track record, our migration analysis of the Accolade stem is somewhat concerning. Thirty three percent of stems had reached the 1.5 mm subsidence point by two years. This is of concern as work has previously shown this to predict failure of stems with aseptic loosening at ten years with an accuracy of 79%. If these stems go on to fail at the predicted rate this would represent an unacceptably high level of failure. Our data raises serious concerns about the overall clinical performance of this stem design due to poor initial stability and integration.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 578 - 578
1 Nov 2011
Almousa S Beaulé PE
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Purpose: Iatrogenic acetabular retroversion is a known complication after pelvic osteotomy leading to persistent hip pain and increasing risk of subsequent osteoarthritis. The purpose of this study is to document the incidence of acetabular retroversion and signs of impingement in patients who have had a Salter pelvic osteotomy in childhood.

Method: Twenty eight patients (32 hips) had a Salter Osteotomy between 1980 and 1999, 16 were lost to follow-up. Of the 12 studied, eight had a diagnosis of DDH and four had Legg Calve Perthes. Clinical assessment for the presence of the impingement sign, range of motion and leg length discrepancy was done as well as functional scores. AP pelvic radiographs were taken to assess acetabular retroversion (cross-over or ischial sign), osteoarthritis using the Tonnis grade, center-edge and Tonnis angles.

Results: The mean age of the sample was 17.25 years (SD=7.27) with a mean follow-up of 10.56 years (SD=6.27). Impingement sign was positive in seven patients (58.3%). Nine out of the 12 had acetabular retroversion. Nine had Tonnis grade 1, two Tonnis grade 2, and one had a Tonnis grade 3. Mean center edge and Tonnis angles were 26° (SD=16.43) and 9.09° (SD=6.49), respectively. There was no correlation between presence of acetabular retroversion with Tonnis grade (p=.700), hip pain (p=.317) or impingement sign (p=.621).

Conclusion: Retroversion is highly prevalent (69.2%) in patients who underwent a Salter pelvic osteotomy for a childhood hip disease. Although acetabular retroversion is a known cause of impingement in adulthood, our patient cohort was too small to detect a significant impact on the functional scores.


The Journal of Bone & Joint Surgery British Volume
Vol. 91-B, Issue 5 | Pages 589 - 594
1 May 2009
Allen D Beaulé PE Ramadan O Doucette S

Femoroacetabular impingement is a cause of hip pain in adults and is potentially a precursor of osteoarthritis. Our aim in this study was to determine the prevalence of bilateral deformity in patients with symptomatic cam-type femoroacetabular impingement as well as the presence of associated acetabular abnormalities and hip pain. We included all patients aged 55 years or less seen by the senior author for hip pain, with at least one anteroposterior and lateral pelvic radiograph available. All patients with dysplasia and/or arthritis were excluded. A total of 113 patients with a symptomatic cam-impingement deformity of at least one hip was evaluated. There were 82 men and 31 women with a mean age of 37.9 years (16 to 55).

Bilateral cam-type deformity was present in 88 patients (77.8%) while only 23 of those (26.1%) had bilateral hip pain. Painful hips had a statistically significant higher mean alpha angle than asymptomatic hips (69.9° vs 63.1°, p < 0.001). Hips with an alpha angle of more than 60° had an odds ratio of being painful of 2.59 (95% confidence interval 1.32 to 5.08, p = 0.006) compared with those with an alpha angle of less than 60°. Of the 201 hips with a cam-impingement deformity 42% (84) also had a pincer deformity.

Most patients with cam-type femoroacetabular impingement had bilateral deformities and there was an associated acetabular deformity in 84 of 201 patients (42%). This information is important in order to define the natural history of these deformities, and to determine treatment.


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 8 | Pages 1019 - 1024
1 Aug 2008
Cashin M Uhthoff H O’Neill M Beaulé PE

Damage to and repair of the acetabular labral-chondral complex are areas of clinical interest in the treatment of young adults with pain in the hip and in the prevention of degenerative arthritis of the hip. There are varying theories as to why most acetabular tears are located anterosuperiorly. We have studied the prenatal development of the human acetabular labral-chondral complex in 11 fetal hips, aged from eight weeks of gestation to term.

There were consistent differences between the anterior and posterior acetabular labral-chondral complex throughout all ages of gestation. The anterior labrum had a somewhat marginal attachment to the acetabular cartilage with an intra-articular projection. The posterior labrum was attached and continuous with the acetabular cartilage. Anteriorly, the labral-chondral transition zone was sharp and abrupt, but posteriorly it was gradual and interdigitated. The collagen fibres of the anterior labrum were arranged parallel to the labral-chondral junction, but at the posterior labrum they were aligned perpendicular to the junction.

We believe that in the anterior labrum the marginal attachment and the orientation of the collagen fibres parallel to the labral-chondral junction may render it more prone to damage than the posterior labrum in which the collagen fibres are anchored in the acetabular cartilage. The anterior intra-articular projection of the labrum should not be considered to be a pathological feature.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 155 - 155
1 Mar 2008
Amstutz HC Antoniades J Le Duff MJ Beaulé PE
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Obtaining fixation in DDH with Surface arthroplasty (SA) with a two part polyethylene (PE ) socket was technically challenging. Although dislocation was rare there was a high loosening rate secondary to polyethylene wear. The purpose of this study was to evaluate the results of Conserve Plus metal-on-metal SA in Crowe class I and II Developmental Dysplasia of the Hip patients.

54 patients (59 hips), 72% females, average age43.7 years (15 to 63.8) met these inclusion creteria with 2 years of follow-up minimum. Seven hips were Crowe type II and fifty-two were type I.

Harlan C. Amstutz, John Antoniades, Michel J. Le Duff, Paul E. Beaulé

The results of MMSA are much improved over those of prior generations of SA and socket fixation is stable even in Crowe type II with the porous coated acetabular components without adjuvant fixation despite incomplete acetabular coverage of the socket. The hips have-been stable even with important range of motion. Recent short term failure and radiolucencies have been eliminated by improved technique despite a high incidence of femoral cysts and reduced area of fixation.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 154 - 155
1 Mar 2008
Amstutz HC Campbell PA Beaulé PE
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The purpose of the present study was to identify risk factors for femoral loosening and neck fracture for Conserve+ metal-on-metal hybrid surface atrhroplasty.

The first 500 hips (of over 700 implanted by the senior author) in 436 patients were reviewed. Mean age was 48.6 with 74% of males patients.

16 hips were converted to THR secondary to aseptic failure on the femoral side (11 femoral component loosenings and 5 femoral neck fractures). 14 hips showed radiolucencies around the short metaphyseal stem at last follow-up. A retrieval analysis was performed and analyzed specimens compared with the intra operative photos of the prepared femoral head and the post-op X-rays. The cause of neck fractures is multifactorial. Risk factors include: uncovered reamed bone, leaving the component proud, notching the neck, impingement, osteopenia and cysts, and trauma. Avoidance of technical deficiencies and proper patient selection can eliminate neck fractures. Loosening is also multifactorial. Risk factors for loosening included: cysts > 1 cm, small femoral head size, female gender, early cases (before improved acrylic fixation including femoral suctioning measures were instituted) and reduced stem shaft angle.

Meticulous initial preparation of the femoral bone surfaces, drying with suctioning, and maximizing the fixation area are critical when the fixation area is small, especially with osteopenia and cystic degeneration. These techniques have dramatically diminished the incidence of loosening and radiolucencies. Cementing the femoral metaphyseal stem is a meaningful technical improvement towards the prevention of early femoral failure in patients with risk factors.


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 5 | Pages 595 - 598
1 May 2007
May O Matar WY Beaulé PE

Femoroacetabular impingement is recognised as being a cause of labral tears and chondral damage. We report a series of five patients who presented with persistent pain in the hip after arthroscopy for isolated labral debridement. All five had a bony abnormality consistent with cam-type femoroacetabular impingement. They had a further operation to correct the abnormality by chondro-osteoplasty of the femoral head-neck junction. At a mean follow-up of 16.3 months (12 to 24) all had symptomatic improvement.


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 1 | Pages 9 - 15
1 Jan 2007
Beaulé PE Harvey N Zaragoza E Le Duff MJ Dorey FJ

Because the femoral head/neck junction is preserved in hip resurfacing, patients may be at greater risk of impingement, leading to abnormal wear patterns and pain. We assessed femoral head/neck offset in 63 hips undergoing metal-on-metal hip resurfacing and in 56 hips presenting with non-arthritic pain secondary to femoroacetabular impingement. Most hips undergoing resurfacing (57%; 36) had an offset ratio ≤ 0.15 pre-operatively and required greater correction of offset at operation than the rest of the group. In the non-arthritic hips the mean offset ratio was 0.137 (0.04 to 0.23), with the offset ratio correlating negatively to an increasing α angle. An offset ratio ≤ 0.15 had a 9.5-fold increased relative risk of having an α angle ≥ 50.5°. Most hips undergoing resurfacing have an abnormal femoral head/neck offset, which is best assessed in the sagittal plane.


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 6 | Pages 838 - 838
1 Jun 2006
BEAULÉ PE


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 1 | Pages 35 - 39
1 Jan 2006
Beaulé PE Campbell PA Hoke R Dorey F

During hip resurfacing arthroplasty, excessive valgus positioning or surgical technique can result in notching of the femoral neck. Although mechanical weakening and subsequent fracture of the femoral neck are well described, the potential damage to the retinacular vessels leading to an ischaemic event is relatively unknown. Using laser Doppler flowmetry, we measured the blood flow in 14 osteoarthritic femoral heads during routine total hip replacement surgery, before and after notching of the femoral neck. In ten hips there was a reduction in blood flow of more than 50% from the baseline value after simulated notching of the femoral neck. Our results suggest that femoral head vascularity in the osteoarthritic state is similar to the non-arthritic state, where damage to the extraosseous vessels can predispose to avascular necrosis. Surgeons who perform resurfacing arthroplasty of the hip should pay careful attention to these vessels by avoiding excessive dissection around the femoral neck and/or notching.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 10 | Pages 1391 - 1396
1 Oct 2005
Griffin DB Beaulé PE Matta JM

There remains uncertainty about the most effective surgical approach in the treatment of complex fractures of the acetabulum. We have reviewed the experience of a single surgeon using the extended iliofemoral approach, as described by Letournel.

A review of the database of such fractures identified 106 patients operated on using this approach with a minimum follow-up of two years. All data were collected prospectively. The fractures involved both columns in 64 (60%). Operation was undertaken in less than 21 days after injury in 71 patients (67%) and in 35 (33%) the procedure was carried out later than this. The reduction of the fracture was measured on plain radiographs taken after operation and defined as anatomical (0 to 1 mm of displacement); imperfect (2 to 3 mm) or poor (> 3 mm). The functional outcome was measured by the modified Merle d’Aubigné and Postel score. The mean follow-up was for 6.3 years (2 to 17).

All patients achieved union of the fractures. The reduction was graded as anatomical in 76 (72%) of the patients, imperfect in 23 (22%), and poor in six (6%). The mean Merle d’Aubigné and Postel score was 15 (5 to 18) with 68 patients (64%) showing good or excellent and 38 (36%) fair or poor results. Function correlated significantly with the accuracy of the reduction (p < 0.009). Significant heterotopic ossification developed in 32 patients (30%) and was associated with a worse mean Merle d’Aubigné and Postel score of 13.7.

The extended iliofemoral approach can be performed safely in selected complex acetabular fractures with an acceptable clinical outcome and rate of complications. Effective prophylaxis against heterotopic ossification should be strongly considered.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 5 | Pages 741 - 744
1 May 2005
Beaulé PE Krismer M Mayrhofer P Wanner S Le Duff M Mattesich M Stoeckl B Amstutz HC Biedermann R

Studies on the migration of an implant may be the only way of monitoring the early performance of metal-on-metal prostheses. The Ein Bild Roentgen Analyse - femoral component analysis (EBRA-FCA) method was adapted to measure migration of the femoral component in a metal-on-metal surface arthroplasty of the hip using standard antero-posterior radiographs. In order to determine the accuracy and precision of this method a prosthesis was implanted into cadaver bones. Eleven series of radiographs were used to perform a zero-migration study. After adjustment of the femoral component to simulate migration of 3 mm the radiographs were repeated. All were measured independently by three different observers.

The accuracy of the method was found to be ± 1.6 mm for the x-direction and ± 2 mm for the y-direction (95% percentile). The method was validated using 28 hips with a minimum follow-up of 3.5 years after arthroplasty. Seventeen were sound, but 11 had failed because of loosening of the femoral component. The normal (control) group had a different pattern of migration compared with that of the loose group. At 29.2 months, the control group showed a mean migration of 1.62 mm and 1.05 mm compared with 4.39 mm and 4.05 mm in the failed group, for the centre of the head and the tip of the stem, respectively (p = 0.001). In the failed group, the mean time to migration greater than 2 mm was earlier than the onset of clinical symptoms or radiological evidence of failure, 19.1 versus 32.2 months (p = 0.001) and 24.8 months (p = 0.012), respectively.

EBRA-FCA is a reliable and valid tool for measuring migration of the femoral component after surface arthroplasty and can be used to predict early failure of the implant. It may be of value in determining the long-term performance of surface arthroplasty.


The Journal of Bone & Joint Surgery British Volume
Vol. 85-B, Issue 3 | Pages 462 - 462
1 Apr 2003
BEAULÉ PE


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages 67 - 67
1 Mar 2002
Beaulé PE Dory F Matta JM
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Purpose: A classification system for fractures is an important communication tool for surgeons allowing the development of management schemes as well as an estimation of the prognosis. The purpose of our work was to evaluate the inter- and intra-observer reproducibility of the Letournel classification system for acetabular fractures.

Material methods and results: Sixty-five x-rays (AP and Judet views) and computed tomography (CT) series were chosen at random from a data base containing 800 fractures. The distribution of the fracture types followed data in the literature. Three groups of observers were formed, each composed of three orthopaedic surgeons. Group 1 included surgeons who had studied with Letournel, group 2 surgeons specialised in acetabular fractures, and group 3 surgeons qualified for general traumatology surgery. The kappa coefficient was determined to assess agreement between observers. Each observer read the images twice without knowledge of the treatment. The observers first classed the fractures using the x-rays alone then with the x-rays in combination with the CT. Two sessions were organised, two months apart to avoid any possible memorisation. Reproducibility without then with CT for the first session were: group 1: 0.07 and 0.74; group 2: 0.71 and 0.69; group 3: 0.51 and 0.512. Results were similar in the second session. Intra-observer reproducibility without then with CT was: group 1: 0.80 and 0.83; group 2 0.80 and 0.80; group 3: 0.64 and 0.69. Among the six more experimented observers (groups 1 and 2), 100% agreement was found for 66% of the x-rays compared with 22% for the new observers.

Discussion and conclusion: The Letournel classification system using x-rays in combination or not with CT is reliable (kappa > 7) for properly trained surgeons with regular experience in treating acetabular fractures. The value of the CT in the assessment of acetabular fractures is well established for identifying detached elements and joint crush. Conversely, CT does not appear to be essential to class ace-tabular fractures. The Letournel classification can be used as a reliable tool for the description of acetabular fractures and taught to surgeons desiring to undertake regular treatment of these fractures.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 67
1 Mar 2002
Beaulé PE Griffin D Matta J
Full Access

Purpose: Diverse extended approaches have been described for the treatment of complex acetabular fractues. Little data is however available concerning the results, morbidity, and complications of acetabular fractures treated with this approach. The purpose of this work was to assess outcome in procedures performed by a single operator using the extended iliofemoral approach as described by Letournel for the treatment of acetabular fractures.

Material and methods: The database of the senior author included 833 acetabular fractures, 156 of which were operated via the extended iliofemoral approach in 109 patients who had a minimal two years follow-up. The series included 69 women and 40 men, mean age 34 years (11–93). Fracture type was: BC 64; TR+PW 15; T 12; ACH: 3; PW: 2; AC: 2. Delay before surgery was less than 21 days for 76 patients, between 21 days and three months for 22 and greater than three months for 11. There was a femoral head injury in 21% of the cases and 6% had had an earlier operation.

Results: At mean follow-up of 5.4 years (2–12), all fractures had healed. Reduction was anatomic in 69% of the cases, imperfect in 13ù and fair (interfragment gap > 3 mm) in 18%. The mean Postel Merle d’Aubigné score was 15 (5–18) with 63% excellent or good results. Complications were observed in 9% of the cases: seven infections, two serous discharges, and one necrosis of the scar borders. Ectopic ossifications were noted in 56% of the patients, 16% required surgical resection. Total arthroplasty was performed for 7% of the patients, arthrodesis for 4% and haematoma evacuation for 8%. The arthroplasty was revised two years after recurrent dislocation in one patient.

Discussion: This work allows us to conclude that the extended iliofemoral approach is safe and effective for the treatment of complex acetabular fractures. The percentage of excellent and good results is closely related to the quality of the reduction, and can be considered satisfactory known that the extended iliofemoral approach is used for more complex fractures less susceptible of healing. We recommend this approach for experimented operators well trained in the use of the iliofemoral approach.