Femoral cement-in-cement revision is a well described technique to reduce morbidity and complications in hip revision surgery. Traditional techniques for septic revision necessitate removal of all bone cement from the femur. In our two institutions, we have been using a cement-in-cement technique, leaving the distal femoral cement in selected cases for septic hip revision surgery. Between February 2010 and September 2019, 89 patients with prosthetic hip infection underwent first or single stage procedures leaving the distal femoral cement in situ and performing a cement-in-cement revision. The mean patient age was 72.0 years (24–92). The median time from the last arthroplasty procedure was 29.0 months (1–294). 81 patients underwent revision using a cemented Exeter stem, 7 patients received an articulating spacer, and one patient underwent excision arthroplasty with the distal cement left in situ. Patients received clinical and radiographic follow-up with a mean of 42.8 months (range 11.0–120.1 months). Oxford hip scores were collected from each institution's existing databases. 9 patients (10.1%) died within one year of surgery. No deaths were directly related to joint infection or the surgery. One patient was lost to follow up before one year. Of the remainder, 7 patients (8.9%) required further procedures for infection and were therefore considered to be treatment failures. 6 patients (7.6%) underwent planned second stage procedures with no recurrence of infection. 7 patients (8.9%) had further surgery for non-infective reasons. The Kaplan-Meier estimate of infection free survival at one year was 93.7% (95% CI 88.4 to 99.0%). No patients underwent revision for stem loosening. Oxford hip scores were available at over one year postoperatively for 51 patients with a mean score of 30.6, and a mean gain of 11.9. In our combined cohort of patients, cement-in-cement revision had an infection eradication rate of 91.1%. Patient selection is crucial, and the procedure can only be performed when there is a well-fixed cement mantle. However, when strict criteria are followed, this technique offers potential significant benefits to surgeons performing this challenging surgery, and more importantly the patients undergoing them.
Analysis of registry data shows that few units achieve results better than 99·98% control limits. Implant selection is considered a predictor of outcome variation in joint replacement. We analysed the outcomes of a unit with statistically “better than expected” results and compared to all other units within the National Joint Registry for England, Wales, Northern Ireland and Isle of Man (NJR). We sought to determine whether improved implant survival following primary total hip replacement (THR) is a centre effect or mediated by implant selection. We identified 664,761 THRs in the NJR. The exposure was the unit in which the THR was implanted and the outcome all-cause revision. Net failure was estimated using Kaplan-Meier and adjusted analyses used flexible parametric survival analysis.Introduction
Methods
Varus alignment of the femoral component in total hip arthroplasty (THA) is thought to be a risk factor for implant loosening and early revision surgery. The purpose of this study was to evaluate whether the Exeter stem tolerates varus alignment and assess if this theoretical malalignment has an influence on clinical outcomes. A total of 4126 consecutive THAs were reviewed for patients between 2006 and 2012 to allow for a minimum five-year follow-up. To determine the effects of the stem alignment on results, the hips were classified into 3 groups on the basis of stem alignment in initial postoperative anteroposterior radiographs. The alignment of the stem was defined as neutral, valgus (≥ 3° of lateral deviation), or varus (≥ 3° of medial deviation). The primary outcome was all cause revision with patient related outcomes assessed with Oxford hip score pre and post-operatively.Introduction
Methods
Rationing of orthopaedic services is increasingly being used by Care Commissioning Groups (CCG) within the United Kingdom to restrict the numbers of patients being referred for Total Hip Arthroplasty (THA). In Devon, only patients with an Oxford Hip Score (OHS) less than 20 are referred on for specialist Orthopaedic Review. The aim of this study was to look at long term outcomes after THA to see if this rationing has any rational base to justify its use Consecutive patients undergoing THA in Exeter between 1996 and 2012 had OHS' collected prospectively pre-operatively and a minimum of 4 years post-operatively. These scores were analysed looking for trends in patient related outcome scores.Introduction
Methods
The SPAIRE technique (Spare Piriformis And Internus, Repair Externus) involves a muscle sparing mini-posterior approach to the hip. Evidence will be prevented that the principle function of the “short external rotator” muscle group is primarily as an abductor and extensor of the flexed hip and has a profound influenced on weight bearing rising and propulsive motions; also that details of the insertions of the piriformis tendon and conjoint insertion of obturator internus and the gemelli (the Quadriceps Coxa) have previously been poorly appreciated. We have developed a surgical technique (SPAIRE) during which the only tendon released, and subsequently repaired, is obturator externus. The author has carried out the SPAIRE technique for all routine hip arthroplasties for the last 18 months. This cohort has been compared with a matched control group for a comprehensive array of outcome measures. Results show no disadvantage of using the technique. On-table stability is so impressive that when the SPAIRE technique has been used no postoperative restrictions whatsoever are placed on the patient who is immediately encouraged to exercise the hip through a full excursion of movement. Fewer tendons are damaged using the SPAIRE technique than any other approach to the hip including Direct Anterior and Direct Superior approaches. Randomised prospective studies are on-going using objective measurements of Gait and muscle power as well as functional and patient reported outcomes to prove benefit of the SPAIRE technique. For hemiarthroplasty cases a separate RCT is being undertaken comparing the SPAIRE technique with a direct lateral approach. It is believed that this technique may become the default technique for hemi- and total- hip arthroplasty through a posterior approach and for all hip fracture arthroplasty cases.
The risk of dying following total hip replacement (THR) is low and has declined over the last decades. The influence of comorbidities and worse physical status on mortality leads to the idea that patient-reported health status may also be a predictor of mortality. Although this has not been demonstrated in THR surgery, some studies in other fields have reported an association. The aim of this study was to investigate the relationship between patient-reported health status before THR and the risk of dying up to 5 years post-operatively. The Swedish Hip Arthroplasty Register runs a nationwide PROMs program including the EQ-5D questionnaire to routinely monitor patients undergoing THR in Sweden. For these analyses, we used register data on 42,862 patients with hip osteoarthritis operated with THR between 2008 and 2012. Relative survival ratio was calculated by dividing the observed survival in the patient group by age- and gender-adjusted expected survival of the general population. Multivariable modelling proceeded with time-transformed Cox proportional hazards. Pre-operative responses to the five EQ-5D dimensions along with age, gender, education status, year of surgery, and hospital type were used as independent variables. As a group THR patients had a better survival than the general population. Broken down by the five EQ-5D dimensions we observed differentiated survival patters. For all dimensions, those reporting moderate problems (level 2) had higher mortality than those reporting no problems (level 1) and those reporting extreme problems (level 3) had higher mortality than those reporting level 1 or 2. Worse health status according to the EQ-5D before THR is associated with higher mortality up to five years after surgery. The complexity of the interactions between different patient-factors associated with outcomes complicates accurate assessments of risks and expected benefits for individual patients. EQ-5D responses may be useful in a multifactorial individualized risk assessment before THR.
Prospectively collected data is an important source of information subjected to change over time. What surgeons were doing in 1999 might not be the case anymore in 2016 and this change in time also applies to a number of factors related to the performance and outcome of total hip replacement. We evaluated the evolution of factors related to the patient, the surgical procedure, socio-economy and various outcome parameters after merging the databases of the Swedish Hip Arthroplasty Register, Statistics Sweden and the National Board of Health and Welfare. Data on 193,253 THRs (164,113 patients) operated between 1999 and 2012 were merged with databases including general information about the Swedish population and about hospital care. We studied the evolution of surgical volume, patient demographics, socio-economic factors, surgical factors, length of stay, mortality rate, adverse events, re-operation and revision rates and PROMs. Most patients were operated because of primary osteoarthritis and this share increased further during the period at the expense of decreasing number of patients with inflammatory OA and hip fracture. Comorbidity and ASA scores increased for each year. The share of all cemented implants has dropped from 92% to 68% with a corresponding increase of all uncemented from 2% to 16%. Length of stay decreased with about 50 percent to 4.5 days in 2012. The 30- and 90-day mortality rate dropped to 0.4% and 0.7%. Re-operation and revision rates at 2 years were lower in the more recent years. The postoperative PROMs are improving despite the preoperative pain scores getting worse. Even in Sweden, always been considered as a very conservative country with regards to hip replacement surgery, the demographics of the patients, the comorbidities and the primary diagnosis for surgery are changing. Despite these changes the outcomes like mortality, re-operations, revisions and PROMs are improving.
When Radiolucent lines (RLL) are observed around cemented acetabular components, they may progress and be associated with loosening. We reviewed the incidence and progression of RLLs around the Exeter Contemporary flanged acetabular component and compared our results with other published series. We reviewed a consecutive series of 203 sockets with a minimum 10-year follow-up. Up to date radiographs were reviewed by 2 independent assessors for the presence, location and thickness of RLL and an assessment for loosening/migration was made. Initial post-operative radiographs were examined for any case with RLLs at review. There were no revisions for aseptic loosening. 103 hips remained in situ with a minimum follow up of 10 years. Lucent lines were seen on 37/103 (36%) of hips with a mean follow up of 12.1 years (10.0–13.9 years). In these 37 hips, the lucency was present in one zone in 84%, two zones in 8% and all three zones in 8%. Of the 37 hips with a RLL at minimum 10 years follow up, five exhibited a RLL immediately post-operatively. All 5 of these lines were initially isolated to zone 1 and progressed over the 10 years around at least 1 more zone. Only one line became circumferential, although the cup did not migrate. Compared to previous papers (DeLee & Charnley, Hodgkinson and Garcia-Cimbrelo) the presence of RLL at 10 years is reduced in our series (table 2) and no cup migrated. All RLL seen in cups at both 10 years and immediate post-operatively in our series progressed (table 3), unlike in the previous studies. This reduction in lucent lines may be down to modern cementing techniques, cup design or a combination of both. For any figures or tables, please contact the authors directly by clicking on ‘Info & Metrics’ above to access author contact details.
Improvements in function after THA can be evaluated using validated health outcome surveys but studies have shown that PROMs are unreliable in following the progress of individuals. Formal gait lab analysis is expensive, time consuming and fixed in terms of location. Inertial Measurement Units (IMUs) containing accelerometers and gyroscopes can determine aspects of gait kinematics in a portable package and can be used in the outpatient setting (Figure 1). In this study multiple metrics describing gait were evaluated pre- and post THA and comparisons made with the normal population The gait of 55 patients with monarthrodial hip arthrosis was measured pre-operatively and at one year post-surgery. Patients with medical co-morbidity or other condition affecting their gait were excluded. Six IMUs aligned in the sagittal plane were attached at the level of the anterior superior iliac spines, mid-thigh and mid-shank. Data was analysed using proprietary software (Figure 2). Each patient underwent a conventional THA using a posterolateral approach. An identical test was performed one year after surgery. 92 healthy individuals with a normal observed gait were used as controls.Introduction
Methods
The Exeter Hip femoral component remains largely unchanged from the original design, introduced in 1970. It is a highly polished, modular, double tapered stem and has undergone various minor modifications to surface, modularity and most recently the taper; changed to the current V40TM design in 2000. The effect of any design modification cannot easily be foreseen and greater emphasis is now placed on ensuring appropriate monitoring for such implants. We present the results of the first 540 V40TM Exeter THAs performed in our Centre between December 2000 and May 2002. All patients were reviewed prospectively at 1, 5 and 10 years following surgery.Introduction
Methods
Post-operative gait abnormalities are recognized following total hip arthroplasty (THA). Despite global improvement in functional outcome, gait abnormality persists for a decade or more. In this study 3-dimensional gait analysis (3DGA) was performed using a portable system with Inertial Measurement Units (IMUs) to quantify this abnormality. The gait of 55 patients with monarthrodial hip arthrosis was measured pre-operatively and at one year post-surgery. Patients with medical co-morbidity or other conditions affecting their gait were excluded. Six IMUs were aligned at the level of the anterior superior iliac spines, mid-thigh and mid-leg. Data was analysed using proprietary software. Each patient underwent a conventional THA using a posterolateral approach. 92 healthy individuals were assessed for comparison.Introduction
Methods
We report on the outcome of a cemented flanged acetabular component at a minimum of 10 years post-operatively. Two hundred and three hips were reviewed in 194 consecutive patients who underwent primary total hip arthroplasty using this implant. Cases with acetabular defects requiring bone grafting were excluded. Functional and radiological data were prospectively recorded.Introduction
Patients/Materials & Methods
There is sparse evidence regarding the survivorship beyond 20 years of both uncemented and cemented hip replacements in patients 50 years and under. We report a unique series reviewing 20–26 year follow-up of patients ≤50 years with cemented Exeter THR. We reviewed the survivorship with clinical and radiological outcomes of 138 consecutive cemented THR's in 113 patients ≤50 years. The pre-op diagnoses included Osteoarthritis (30%), DDH (25%), RA (9%) and Post traumatic OA (5%), and 31% of patients had previous surgery to the hip. All patients were followed up at 5 year intervals and there was no patient lost to follow up.Introduction
Materials and Methods
Cemented stems have given good results with no difference in outcome when comparing taper slip and composite beam designs in short-term randomised trials. We aimed to ascertain differences in outcome between the different cemented design philosophies using a large-scale registry analysis. A retrospective cohort study of National Joint Registry of England and Wales (NJREW) was conducted. The study population included all primary total hip operations performed in the UK from 1 April 2003 to 31 September 2012. All cemented stems were identified and categorised as taper slip (polished) or composite beam (non-polished).Introduction
Materials and Methods
The design of hip replacements is based on the morphology of the proximal femur. Populations living in hard water regions have higher levels of serum calcium and magnesium which promote bone mineralization. A case control study was performed comparing proximal femoral morphology in patients living in soft and hard water regions to determine whether the effect of water hardness had an implication in the future design of hip-prostheses. The proximal femoral morphology of 2 groups of 70 aged and sex matched patients living in hard and soft water regions at mean age 72.24 (range, 50 to 87 years) were measured using an antero-posterior radiograph of the non-operated hip with magnification adjusted. The medullary canal diameter at the level of the lesser trochanter was significantly wider in patients living in the hard water region (mean width 1.9 mm wider; p=0.003). No difference was found at the isthmus, Dorr index, or cortical bone ratio. In conclusion proximal femoral morphology does differ: a wider medullary canal at the level of the lesser trochanter in hard water regions. This size difference is relatively small and is unlikely therefore to affect the mechanics of the current femoral stem prostheses components.
This study utilised NJR primary hip data from the 6th Annual Report to determine the rate and indication for revision between cemented, uncemented, hybrid and resurfacing prosthetic groups. Regression analysis was performed to identify the influence of gender and ASA grade on these revision rates. Validity of the data was interrogated by exploring for episodes of misclassification. We identified 2,264 misclassified episodes within the four groups (Misclassification rate 2.7% primary, 4.3% revision procedures). Analysis was performed using the “reclassified dataset”. The Kaplan-Meier revision rates at 3 years were 0.9% (95%CI: 0.8%-1.0%) for cemented prostheses, 1.9% (95%CI: 1.8%-2.0%) for uncemented hips, 1.2% (95%CI: 1.0%-1.4%) for hybrids and 3.0%, (95%CI: 2.7%-3.3%) in the resurfacing group. The trends in revision rates were comparable to those published in the NJR (6th Edn.) with significant differences across all groups (p< 0.0001). Revision rates in the under 55 year age group showed an identical hierarchy with cemented and hybrid arthroplasty having the lowest revision rates. Cox Regression analysis indicated that both the prosthesis group in isolation and the interaction between prosthesis group and ASA grade significantly influenced the rate of failure (p< 0.001). Indications for revision showed significant differences in rates for, pain, aseptic loosening, dislocation and malalignment between prosthesis types (p< 0.001). The indications including Aseptic loosening, pain, malalignment and dislocation all demonstrated similar trends in revision rates between prosthetic groups with cemented hips having the lowest rates followed by ascending rates for hybrid, uncemented and resurfacing groups. The exception being dislocation with resurfacings having the lowest revision rates. This study provides important baseline revision rates by indication for each prosthetic group from which future comparisons can be made. Areas of misclassification within the NJR dataset have been reported back for future annual analysis.Results
Discussion
Since 1991 to 2008 approximately 800,000 Exeter stems have been sold worldwide with 80 reported cases of fracture (neck or stem). This study aimed to determine factors predisposing to fracture. Clinical, surgical, radiological and retrieval data was collated from Stryker Benoist-Girard and Exeter research databases. Risk factors associated with fracture were categorised to patient related (weight and activity levels), surgical related (poor medial support, component size, placement) and implant related (+ head).Background
Method
Restoration of an anatomical hip centre frequently requires limb lengthening, which increases the risk of nerve injury in the treatment of Crowe 4 Developmental Dysplasia of the Hip (DDH). Prospective evaluation of the use of subtrochanteric derotational femoral shortening with a cemented Exeter stem. 15 female patients (18 hips – 3 bilateral) with a mean age at time of operation of 51 years followed-up for a mean of 114 months (range 52 to 168). 16 cemented and 2 uncemented acetabular components were implanted. Exeter cemented DDH stems were used in all cases. No patient lost to follow up. All 18 Crowe IV hips reviewed. Charnley-D’Aubigne-Postel score for pain, function and range of movement were improved from a mean of 2-2-3 to 5-4-5 respectively. One osteotomy failed to unite at 14 months and revised successfully. Clinical healing was achieved at a mean of 6 months while radiological evidence of union at a mean of 9 months. The mean length of the excised segment was 3 cm and the mean true limb lengthening was 2 cm. 3.5mm DCP plate with unicortical screws was used to reduce the osteotomy, and intramedullary autografting performed in all cases. Mean subsidence was 1 mm and no stem was found to be loose at the latest follow up. No sciatic nerve palsy was observed and there were no post-operative dislocations. Cemented Exeter femoral components perform well in the treatment of Crowe IV DDH with when a subtrochanteric derotational shortening osteotomy (SDSO) was necessary. A transverse osteotomy is necessary to achieve derotation and reduction can be maintained with a DCP plate. Intramedullary autografting prevents cement interposition at the osteotomy site and promotes healing.
No deep infections or adverse events due to the CaP were reported, with no significant difference in complication rates including revision and re-operations. No significant difference in acetabular migration, femoral subsidence, radiolucencies and lyses between the groups was observed. The independent review found no difference between the groups in terms of migration. The bone density was apparently greater for the ApaPore group at 12 months (p=0.001) and 24 months (p=0.012) although the significance of this is unclear. No significant difference in the clinical measures was observed between the groups.
The demand for primary hip replacements has grown steadily over the past 20 years and continues to do so. The challenge is to deliver a high quality and cost-effective service by developing short-stay pathways to optimise patient care and outcome. A four-day hip protocol was established, with attention to detail on analgesia, thrombo-prophylaxis, mobilisation and patient motivation. A multi-disciplinary team was trained to deliver the pathway on a designated ward for primary hip replacements with the aim to discharge patients on the third post-operative day (four day stay in total). Before the initiation of this audit our average stay for primary hips was nine days. The national average stay is 10.6 days, with the top 10 trusts averaging 6.7 days. In the initial three-month trial, 66 hip replacements (39 females and 27 males) done by the hip team at Princess Elizabeth Orthopaedic Centre in Exeter were audited against the four-day hip protocol. Average age was 72.4 years (range 44 – 92 years). Two patients were discharged on the second post-operative day and another 15 patients on the third post-operative day. As a result, we managed to get 25.8% of the patients home within four days. Overall, the average length of stay was only 6.3 days. In conclusion, while we only achieved our target in 25.8% of patients, the project improved our overall length of stay remarkably. It is clearly evident that a targeted pathway focused to patient care in all aspects using a multi-disciplinary approach can improve the overall service delivery.
The cement in cement technique for revision total hip arthroplasty (THA) has shown good results in selected cases. However results of its use in the revision of hemiarthroplasty to THA has not been previously reported.
Between May 1994 and May 2007 28 (20 Thompson’s and 8 Exeter bipolar) hip hemiarthroplasties were revised to THA in 28 patients using the cement in cement technique. All had an Exeter stem inserted at the time of revision. Clinical and operative data were collected prospectively. Clinical evaluation was by the Charnley, Harris and Oxford hip scores and radiographs were analysed post-operatively and at latest follow up. The mean age at time of hemiarthroplasty revision was 80 (35 to 93) years. The reason for revision was acetabular erosion in 12 (43%), recurrent dislocation in 8 (29%), aseptic loosening in 4 (14%), periprosthetic fracture in 2 (7%) and infection in 2 (7%) patients. No patient has been lost to follow up. 3 patients died within 3 months of surgery. The mean follow up of the remainder was 50 (16 to 119) months. Survivorship with revision of the femoral stem for aseptic loosening as the endpoint was 100%. 3 cases (11%) have since undergone further revision, 1 for recurrent dislocation, 1 for infection, and 1 for periprosthetic fracture. The cement in cement technique can be successfully applied to revision of hip hemiarthroplasty to THA. It has a number of advantages in this elderly population including minimizing bone loss, blood loss and operative time.
Survivorship of the standard Exeter Universal cemented stem with revision of the femoral component for aseptic loosening as the endpoint has been reported as 100% at 12 years. A version for use in smaller femora, the Exeter 35.5 mm stem, was introduced in 1988. Although also a collarless polished taper, the stem is slimmer and 25 mm shorter than a standard stem.
Between August 1988 and August 2003 192 primary hip arthroplasties were performed in 165 patients using the Exeter 35.5 mm stem. Clinical and operative data were collected prospectively. Clinical evaluation was by the Charnley, Harris and Oxford hip scores and radiographs were analysed post-operatively and at latest follow up. The mean age at time of operation was 53 (18 to 86) years with 73 patients under the age of 50 years. The diagnosis was osteoarthritis 91, hip dysplasia in 77, inflammatory arthritis in 18, septic arthritis of the hip in 3, secondary to Perthes disease in 2 and avascular necrosis of the hip in 1 patient. The fate of every implant is known. At a median follow-up of 8 (5 to 19) years survivorship with revision of the femoral stem for aseptic loosening as the endpoint was 100%. 15 cases (7.8%) underwent further surgery – 11 for acetabular revision, 1 for stem fracture and 3 others. Although smaller than a standard Exeter Universal polished tapered cemented stem, with a shorter, slimmer taper, the performance of the Exeter 35.5 mm stem was equally good even in this young, diverse group of patients.
This presentation introduces a new tool to be used in the cementing of acetabular components in total hip arthroplasty, the ‘Rim Cutter’. The Rim Cutter is designed to cut a ledge in the rim of the acetabulum into which a flanged cup can be cemented. The flange is trimmed such that it fits precisely into the ledge cut in the acetabulum. We present the in vitro pilot study of the effect of using this tool on the intra-acetabular cement mantle pressure during cup insertion and also the effect on the depth of cement penetration as the cup is inserted. A significant improvement in both cement pressure and cement penetration over conventional flanged and unflanged cups is noted. Improved cement penetration around the rim of the acetabulum in THR has implications for reducing the rate of aseptic loosening. The pilot study also suggests other beneficial features of using the rim cutter such as improved cup centralisation, control of orientation and the prevention of the cup ‘bottoming out’. Further in vivo studies are required to better assess its efficacy.
Vast amount of literature is available on mechanical properties of PMMA, but not about the composite specimens of old and new cement. This is important, as in cement revision has become established technique with good clinical results. Originally Greenwald and later Li described properties of such specimens. However in these studies the old samples were only few days old, unlike clinical situation, where the old cement is a few years old. We therefore decided to test short-term mechanical properties of composite specimens and compare these with new uniform specimens. We choose specimens of cement 3–17 years old (median 11.8) for the manufacturing of the composite specimens.
We evaluated short-term mechanical properties of composite specimens and compared these with new uniform specimens.
The average age at operation of the survivors was 55.7 years. No significant radiological subsidence between the cement and bone was found. Mean subsidence between the stem and the cement was 2.15mm, most occurring in the first 5 years and in all but 1 being less than 4. The maximum was 18mm (grade D cementing). Cementing grades were B in 65%, C in 27%, D in 8%. Resorption of the neck (13%) was associated with excessive socket wear or cement left over the cut surface of the neck (the ‘pseudocollar’). Visible cement fractures were found in 14%, none associated with focal lysis, which was seen in 11%.
406 hips in 365 patients remain under active follow up, with 122 patients (134 hips) deceased. Averaged clinical scores taken pre-operatively, 2 years post-operatively, and at latest follow-up show marked and sustained improvement: Charnley Pain 2.7, 5.5, 5.3; Charnley Function 2.1, 4.1, 3.6; Charnley Range of Motion 4.0, 5.4, 5.3; Harris Pain 19, 38, 36; Harris Function 18, 32, 28; and Oxford Hip Score 41, 22, 25. There have been 45 failures (8.3 percent) at an average 7.6 year follow up (range 2.6 – 15.3 years). Technical error contributed to 13 of the 24 non-infective complications, but with improved technique plus the addition of long stemmed impaction grafting, there have been no technical errors since 1996.
Retention of well fixed bone cement at the time of a revision THA is an attractive proposition, as its removal can be difficult, time consuming and may result in extensive bone stock loss or fracture. Previously reported poor results of cemented revision THA, however, have tended to discourage Surgeons from performing “cement in cement” revisions, and this technique is not in widespread use. Since 1989, we have performed a cement within cement femoral stem revision on 354 occasions. The indications for in cement revision included facilitating acetabular revision, replacement of a monoblock stem with a damaged or incompatible head, revision of hemiarthroplasty to THA, component malposition and broken stem. Cement in cement revision was only performed in the presence of well fixed cement with an intact bone-cement interface. An Exeter polished tapered stem was cemented into the existing cement mantle on each occasion. Follow up of 5 years or longer is available for 175 cases, and over 8 years in 41. On no occasion has a cement in cement femoral stem had to be re-revised during this time for subsequent aseptic loosening. Advantages include preservation of bone stock, reduced operating time, improved acetabular exposure and early post operative full weight bearing mobilisation. This technique has not been used for 1 stage revision of infection. This experience has encouraged the refinement of this technique, including the development of a new short stem designed specifically for cement within cement revisions. This stem is designed to fit into an existing well fixed cement mantle of most designs of cemented femoral component or hemi-arthroplasty, with only limited preparation of the proximal mantle required. The new stem greatly simplifies cement in cement revision and minimises the risk of distal shaft perforation or fracture, which is otherwise a potential hazard when reaming out distal cement to accommodate a longer prosthesis.
The average age at operation of the survivors was 57.6 years. No significant radiological subsidence between the cement and bone was found. Mean subsidence between the stem and the cement was 2.15mm, most occurring in the first five years and in all but one being less than four. The maximum was 18mm (grade D cementing). Cementing grades were B in 65%, C in 27%, D in 8%. Resorption of the neck (13%) was associated with excessive socket wear or cement left over the cut surface of the neck (the ‘pseudocollar’). Visible cement fractures were found in 14%, none associated with focal lysis, which was seen in 11%.
Radiological analysis of the pre-operative, immediate post-operative and most recent follow-up radiographs was also performed. This included evaluation of the cement mantle and impacted allograft, stem subsidence within the cement mantle, presence of cortical healing and graft trabeculation on the follow-up radiographs, as well as appearance of radiolucencies and graft resorption.
There have been 45 failures (8.3 percent) at an average 7.6-year follow-up (range 2.6–15.3 years). Technical error contributed to 13 of the 24 non-infective complications, but with improved technique plus the addition of long stemmed impaction grafting, there have been no technical errors since 1996.
A comparison of the clinical status and outcome of a group of patients treated with tw-stage revision using either excision arthroplasty or an articulating spacer (the Kiwi Prostalac) as the first stage is presented. Clinical scores were obtained before revision, after the first stage, and after the second stage revision, along with the outcome of the success of the revision procedure in terms of eradication of the infection, from the two study groups. Seven patients received excision arthroplasty and eight were treated with the Kiwi Prostalac spacer, at the treating surgeon’s discretion. A comparison of the clinical status of the two groups will be presented at the varying stages of treatment, along with hospitalisation duration, and morbidity and ultimate outcome. Our results demonstrate that two-stage revision with an antibiotic cement-coated THJR prosthesis (The Kiwi Prostalac) is an effective and safe method of managing deep peri-prosthetic infection around a THJR with significant advantages to the patient.
Impaction bone grafting in conjunction with a cemented polished double-taper stem as a technique for revision of the femoral component was introduced in 1987 at our institution. As at January 2000, 540 cases in 487 patients had been performed by multiple surgeons. All procedures have been studied prospectively, and there are no patients lost to follow-up. We present the survivorship and outcome data for these patients. Survivorship at 15 years is 90.6 percent (95 percent confidence interval:88–93 percent). Four hundred and six hips in 365 patients remain under active follow up, with 122 patients (134 hips) deceased. Averaged clinical scores taken preoperatively, 2 years postoperatively and at latest follow up showed marked and sustained improvement: Charnley Pain 2.7, 5.5, 5.3; Charnley Function 2.1, 4.1, 3.6; Charnley Range of Motion 4.0, 5.4, 5.3; Harris Pain 19, 38, 36; Harris Function 18, 32, 28; and Oxford Hip Score 41, 22, 25. There have been 45 failures (8.3 percent) at an average 7.6 year follow up (range 2.6–15.3 years). Technical error contributed to 13 of the 24 non-infective complications, but with improved technique plus the addition of long stemmed impaction grafting, there have been no technical errors since 1996. Our results show that revision of the femoral component with impaction bone grafting is a reliable and durable technique with an acceptably low complication rate with excellent survivorship at 15 years.
In relation to the conduct of this study, one or more the authors have received, or are likely to receive direct material benefits.
To establish the efficacy of femoral impaction grafting in femoral reconstruction following sepsis, we identified and reviewed all cases of two stage hip revision for sepsis in which femoral impaction grafting was used in the second stage, performed in Exeter from 1989 until the end of 1998. All patients underwent a Girdlestone excisional arthroplasty, were prescribed local and systemic antibiotic treatment, and then subsequently underwent surgical reconstruction, using femoral impaction grafting. These 53 cases represent a subgroup of our patients who had received a two-stage revision for infection during that period. The other patients did not require femoral grafting. 4 patients died within 24 months of surgery. 4 patients became reinfected (7.5%), and 1 patient underwent stem revision for a fracture below the tip of the stem at 10 months, leaving 44 patients with an average of 53 months follow up (range 24 to 122 months). These 44 patients all demonstrated improved clinical scores and satisfactory radiological outcomes. Our clinical results reveal post-operative scores approaching those for primary arthroplasty. Our intermediate term results justify the use of fresh frozen allograft bone in the second stage of revisional hip surgery for its low incidence of reinfection and loosening, and potential to improve bone stock.
We report the histology of a femur retrieved 3.5 years after a cemented revision of a hip replacement in which impaction allografting had been used to fill two large cortical defects. The allograft chips had largely been replaced by viable cortical bone, and the interface between cement and tissue resembled that seen after primary cemented arthroplasty.
We report the results of using impacted cancellous allografts and cement for fixation of the femoral component when revision arthroplasty is required in the face of lost bone stock. In 56 hips reviewed after 18 to 49 months there were few complications and a majority of satisfactory results with evidence of incorporation of the graft. Further study and review are necessary, but the use of the method appears to be justified.