Aims

The Advance Medial-Pivot total knee arthroplasty (TKA) was designed to reflect contemporary data regarding the kinematics of the knee. We wished to examine the long-term results obtained with this prosthesis by extending a previous evaluation.

We report the results at a mean of 24.3 years (20 to 32) of 61 previously reported consecutive total hip replacements carried out on 44 patients with severe congenital hip disease, performed with reconstruction of the acetabulum with an impaction grafting technique known as cotyloplasty. The mean age of the patients at operation was 46.7 years (23 to 68) and all were women. The patients were followed post-operatively for a mean of 24.3 years (20 to 32), using the Merle d’Aubigné and Postel scoring system as modified by Charnley, and with serial radiographs. At the time of the latest follow-up, 28 acetabular components had been revised because of aseptic loosening at a mean of 15.9 years (6 to 26), and one at 40 days after surgery because of repeated dislocations. The overall survival rate for aseptic failure of the acetabular component at ten years was 93.1% (95% confidence interval (CI) 86.5 to 96.7) when 53 hips were at risk, and at 23 years was 56.1% (95% CI 49.4 to 62.8), when 22 hips remained at risk. These long-term results are considered satisfactory for the reconstruction of an acetabulum presenting with inadequate bone stock and circumferential segmental defects.

Cite this article: Bone Joint J 2013;95-B:887–92.

Advance medial pivot total knee replacement has been designed to reflect contemporary data regarding knee kinematics. We report the clinical outcome of 284 replacements in 225 consecutive patients. All patients were prospectively followed for a mean of 7.6 years (5 to 9) using validated rating systems, both objective and subjective.

All patients showed a statistically significant improvement (p~0.01) on the Knee Society clinical rating system, WOMAC questionnaire, SF-12 questionnaire, and Oxford knee score. The majority of patients (92%) were able to perform age appropriate activities with a mean knee flexion of 117° (85 to 135). Survival analysis showed a cumulative success rate of 99.1% (95% CI, 86.6 to 100) at five years and 97.5% (95% CI, 65.6 to 100) at seven years. Two (0.7%) replacements were revised due to aseptic loosening, one (0.35%) due to infection and one (0.35%) due to a traumatic dislocation. In only two (0.7%) replacements, progressive radiological lucent lines (combined with beta angle of 85°) were observed

Two-staged revision TKA is a common strategy for the management of infected TKA (i-TKA) in properly selected patients. However, there is considerable variation in the parameters (e.g. the duration of intravenous administration of antibiotics and of the time interval between the stages, the intraoperative use of frozen sections, the use of knee aspiration etc.) of the treatment protocol among Orthopaedic Centres making the comparative evaluation of results difficult. The aim of this study is to present a standardised two-staged revision protocol with satisfactory mid-term clinical outcome.

Thirty-four consecutive cases of infected primary TKAs were treated in our department between 2000 and 2006. For 24 of them the postoperative follow-up is greater than 2 years. All patients underwent the same treatment protocol: knee aspiration prior to implant removal and surgical debridement, more than 5 specimens for frozen sections and cultures (aerobic, anaerobic and fungi) during the first stage, custom antibiodic impregnated cement spacers, intravenous administration of antibiotics for 3 weeks followed by 3 weeks of per os administration based on culture and antibiogram, a 6-week interval free from antibiotics, second aspiration and second stage with repetition of frozen sections and cultures. In the case of positive frozen section specimens during the second stage the implantation of a new prosthesis was cancelled and a different management strategy was introduced. Preoperative and postoperative data were collected in the form of Total Knee Society Score (knee score and functional score), Oxford-12 Score, laboratory parameters and radiographs at regular intervals.

At the final follow-up 22 out of 24 patients were free of infection. In four patients (2 Host C and 1 Host B) the 2nd stage was repeated (2–6 times) due to polymicrobial infection and positive intraoperative frozen sections. In one of them a knee arthrodesis was finally performed. The diagnostic accuracy of knee aspiration before the 1st stage was low. Total Knee Society Score rose from a preoperative average of 64 (50 to 95) to a postoperative average of 145 (130 to 180). The Oxford 12 score also rose from a preoperative average of 52 (44 to 58) to a postoperative average of 30 (23 to 38). At the final follow-up no radiological signs of implant loosening were observed.

The above standardised protocol of two-staged revision in i-TKA, when indicated, can provide satisfactory mid-term clinical results.

Aim of the study: To define the dimensions of the radial head, as well as the radiocapitellar and proximal radio-ulnar joints. The most congruent portions of the radial head articulations were determined.

Materials & Methods: Computed tomography scans of twenty-two cadaveric adult elbows were obtained in three forearm positions – supination, neutral, pronation. The radial head dimensions, the radiocapitellar joints, and the proximal radioulnar joints were also measured. Multivariate analysis of variance was used to determine which portions of each articulation were the most congruent.

Results: At the level of the radial trough, the maximum diameter was 22.3 mm, the minimum diameter was 20.9 mm, and the diameter difference was 1.4 mm. This difference represented only 6.3% of the overall maximum diameter. The depth of curvature of the radial head trough was 2.3 mm, the radial head length was 9.8 mm, and the radial neck length was 10.7 mm. At the isthmus of medullary canal, the maximum diameter was 9.7 mm, the minimum diameter was 8.2 mm, and the diameter difference was 1.5 mm. This difference represented 15.6% of the maximum diameter. The average radiocapitellar distance at the radial lip was 4.0 mm, the trough 2.4 mm, and the ulnar lip 2.2 mm. Thus, the radial head tended to become uncovered at the radial lip (p < 0.0001). The radiocapitellar joint was tighter in pronation than in supination (p = 0.0008). The proximal radioulnar joint was most congruent at the MPRUJ (middle proximal radioulnar joint), at the midportion and posterior aspects, rather than the anterior aspect (p < 0.0001). The PRUJ coverage was between 69.0 and 79.2 degrees.

Conclusions: Prosthesis trial sizing should be judged by the articulations providing the most congruency –

1) the ulnar lip or trough of the radiocapitellar joint in pronation and

We report the clinical and radiological results of a two- to three-year prospective randomised study which was designed to compare a minimally-invasive technique with a standard technique in total knee replacement and was undertaken between January 2004 and May 2007. The mini-midvastus approach was used on 50 patients (group A) and a standard approach on 50 patients (group B). The mean follow-up in both groups was 23 months (24 to 35).

The functional outcome was better in group A up to nine months after operation, as shown by statistically significant differences in the mean function score, mean total score and the mean Oxford knee score (all, p = 0.05). Patients in group A had statistically significant greater early flexion (p = 0.04) and reached their greatest mean knee flexion of 126.5° (95° to 135°) 21 days after operation. However, at final follow-up there was no significant difference in the mean maximum flexion between the groups (p = 0.08). Technical errors were identified in six patients from group A (12%) on radiological evaluation.

Based on these results, the authors currently use minimally-invasive techniques in total knee replacement in selected cases only.

Aim: The posterior interosseous nerve (PIN) is often at risk during surgical approaches to the proximal radius. The forearm is pronated during the approach to retract the PIN further away from the dissection. We hypothesized that a fracture of the radius would decrease the protection provided by the pronation maneuver.

Material and Methods: The position of the PIN in cadaveric elbows was measured using CT scans made after the PIN sheath was injected with radiopaque dye. Senventeen elbows were injected and CT scans were made in both full supination and pronation. The same elbows then had a radial osteotomy performed at the proximal-middle third junction and were re-scanned in supination and pronation. Finally the same elbows had the fascia around the osteotomy sutured and were scanned a third time. Measurements on the axial CT scans at the level of the radial head were taken of the angle formed by the olecranon, head, and PIN, as well as of the distance between the PIN and the lateral most aspect of the radial head.

Results: In the control group with intact radii, pronation increased the distance between the lateral radial head and the PIN by 6.44 mm. With radial osteotomy, the mean increase was 3.88 mm. The excursion of the nerve along the long axis of the radius decreased from 29.6 degrees to 23.3 degrees.

Conclusions: Radial osteotomy decreased the excursion of the PIN provided by pronation for the forearm by 40%. The Kocher approach requires additional care in light of a radial shaft fracture, but pronation is still beneficial.

Introduction: Currently, minimal attention has been paid to thorough preoperative planning in primary total knee arthroplasty. The aim of this study was to evaluate the results and the effectiveness of a previously reported x-ray view as a simple way of preoperative planning in total knee arthroplasty.

Materials & Methods: The rotational alignment of the distal end of the femur is usually evaluated by measuring the angle (posterior condylar angle, PCA) between the surgical transepicondylar axis (TEA) and the posterior condylar line (PC line), which connects the posterior aspects of the femoral condyles. A simple and convenient technique for assessing the TEA and PC line using plain radiography is the kneeling view. The kneeling view has been described as a posteroanterior projection at right angles to the tibial shaft with the knee in approximately 80° of flexion and with the hip joint in neutral rotation. Preoperative planning is possible using the kneeling view in measuring the rotational alignment of the distal femur using the posterior condylar angle. Additionally, information about the varus inclination of the upper part of the tibia may be obtained using the same x-ray view. Kneeling views were obtained in fifty patients with advanced osteoarthritis (classified as 4 on the Kellgren–Lawrence scale) that were admitted in our department for primary TKA. The varus inclination of the upper part of the tibia and condylar twist angle were measured using digital protractors.

Results: There was no statistically significant correlation between the posterior condylar angle and the varus inclination of the upper part of the tibia. Bivariate linear regression analysis did not reveal any prediction equation or relation between the two computed variables in advanced osteoarthritic knees.

Conclusions: Using this method of preoperative planning, the current practice of cutting the tibia perpendicular to its mechanical axis and applying a predefined external rotation of the femoral component is strongly disputed, especially in advanced osteoarthritic knees. The results of this study show that preoperative planning may be very helpful in assessing the rotational deformity of the distal femur. The final amount of external rotation of the femoral component must be approached on an individual basis based on a thorough preoperative planning.

Aim: To present the experience of a highly specialized total knee arthroplasty revision center with the use of femoral and tibial components with modular press-fit offset stem extensions.

Methods: Intramedullary press-fit offset stem extensions were developed to offer an additional option when doing a revision total knee arthroplasty in the presence of periarticular bone loss. The radiological and clinical results of a cohort of 28 patients that had been previously subjected to a revision total knee arthroplasty utilizing modular press-fit offset stem extensions, were studied. Mean follow-up time of these patients was 3.5 years (range, 2–7 years). The NexGen Legacy Knee System was used in all our patients (25% LCCK, 75% LPS). The use of bone cement was restricted to the femoral and tibial articular surfaces only, without any intramedullary use.

Results: Femoral intramedullary fit and fill was measured 87.9% in anteroposterior x-rays and 85.5% in laterals. Tibial intramedullary fit and fill was measured 94.5% in anteroposterior x-rays and 89.9% in laterals. Femoral components were implanted in 6.4 degrees of valgus angle (mean values) and 2.5 degrees of flexion (mean values). Tibial components were implanted in 2.2 degrees of valgus angle (mean values) and 3 degrees of posterior slope (mean values). Knee Society Score was 89.5 points, while Function Score was 84.8. One year post-revision follow-up evaluation revealed 89% satisfaction rate among these patients.

Conclusion: The use of these press-fit offset stem extensions, with the best possible intramedullary femoral and tibial fit and fill, offer a very rewarding method and an alternative option to deal with complex reconstructive problems during a revision total knee arthroplasty.

We investigated the effect of calcitonin in the prevention of acute bone loss after a pertrochanteric fracture and its ability to reduce the incidence of further fractures in the same patient.

Fifty women aged between 70 and 80 years who had a pertrochanteric fracture of the hip were randomly allocated to group A (200 IU of nasal salmon calcitonin daily for three months) or group B (placebo).

Patients in group A showed a significantly higher level of total alkaline phosphatase and osteocalcin on the 15th day after injury and a significantly higher level of bone alkaline phosphatase on the 90th day after surgery. These patients also had significantly lower levels of urinary C-telopeptide (CrossLaps) on the 15th, 45th and 90th days after injury and lower levels of urinary hydroxyproline on the 15th and 45th days after injury. Patients in group A had significantly higher bone mineral density at all recorded sites except the greater trochanter at three months and one year after operation. After a four-year period of clinical observation, five patients (24%) in group B sustained a new fracture, in four of whom (20%) it was of the contralateral hip.

Our findings show that calcitonin reduces acute bone loss in patients with pertrochanteric fractures and may prevent the occurrence of new fractures of the contralateral hip in the elderly.

Aims: The purpose of this study was to evaluate the incidence of combined osseous and ligamentous injuries by MRI in patients admitted with displaced or comminuted radial head fractures. Methods: A retrospective study was undertaken on twenty-four consecutive patients with an acute radial head fracture (Mason type II & III) without documented dislocation or tenderness at the distal radioulnar joint (DRUJ). The evaluation was done with elbow antero-posterior and lateral x-ray images and MRI images performed with the patient in a splint in sagittal, coronal, axial, axial oblique and coronal oblique planes. We investigated the integrity of both medial and lateral collateral ligaments, the presence of capitellar osteochondral defects or bone bruises and loose bodies. Results: The MRI evaluation of the participants in this study revealed the presence of a high percentage of ligamentous injuries. The incidence of associated injuries was: medial collateral ligament not intact: 13/24 (54.16%), lateral collateral ligament not intact: 18/24 (80.1%), both collateral ligaments not intact: 12/24 (50%), capitellar osteochondral defects 7/24 (52.4%), capitellar bone bruises 23/24 (95.83%) and loose bodies 22/24 (91.67%). Conclusions: High level of suspicion should be employed when treating displaced or comminuted radial fractures because concurrent osseous and/or ligamentous injuries might be present This speciþc type of injury with the broad range of presentation and accompanying injuries tests the clinician and makes the treatment challenging.

Aims: The purpose of our study was to determine the radiographic anatomy of the proximal radius in three different views in order to identify that position, which has the smallest value for the angle between the axis of forearm rotation (AFR) and the radial neck axis (RNA). It is our hypothesis that such a position should offer the optimal situation for the radial neck cut in radial head replacement, as it will approximate the normal biomechanical axis of forearm rotation. Methods: Anteroposterior (AP) and lateral radiographs of 20 healthy volunteersñ forearms were taken in three views (full supination, neutral, full pronation). Radial head maximum diameter and angular measurements between the axis of forearm rotation (AFR) and the radial neck axis (RNA) were made utilizing digital calipers. Results: Repeated-measures analysis of variance (ANOVA) revealed a statistically signiþcant difference between the three AP groups, with supination having the smallest values (p< 0.0001), but not for the lateral groups (p=0.128). Comparison of the AFR-RNA angle between the AP supinated position and the three lateral views revealed a statistically signiþcant difference among all the pairs with the AP supinated position having the smallest values. Conclusions: The RNA most closely approximates the AFR with the forearm in the supinated position. To best approximate the native AFR during radial head replacement, the cut should be made perpendicular to the neck axis with the elbow extended and the forearm in the supinated position.

Aim: Evaluation of intermediate clinical and radiographic results of displaced intra-articular fractures of the calcaneus treated with ORIF. Materials- Methods: From 1994 to 2002, 167 displaced intra-articular fractures of the calcaneus were treated with ORIF. There were 145 male and 12 female patients. Mean age 34 years. Standard x-rays, Broden views and CT-scan images in coronal and transverse plane were obtained pre and post operatively. Fractures were classified as type III, IV, V according to Sanders. All fractures were approached through an extended lateral L-type approach. AO calcaneal plate was used. Average follow-up was 5 years. Results: In 143 Sanders type III and IV fractures KITA-OKA score was 91. Reduction failure rate was 5.5%(8 pts). 24 patients had Sanders type V fractures and KITAOKA score was 84 and reduction failure rate was 25% (6 pts). 29/167 patients complained of peroneal tendons tenderness which subsided after hardware removal. 79/167 patients had restriction of subtalar joint movements but no complains (SF_36) There were two superficial wound infections and five patients with delayed wound closure. In a group of 45 patients with similar fracture patterns who were treated conservatively, KITA-OKA score was 71, 41 fractures were malunited, 40 patients had moderate to severe pain and early OA sings. Conclutions: Displaced intra-articular fractures of the calcaneus should be treated as any other displaced intra-articular fracture, with open reduction and stable internal fixation

Aim of the study: The outcomes of 50 consecutive patients with chronic periprosthetic total hip arthroplasty infections were evaluated based on a staging system developed at the authors’ institution. The staging system includes three categories: infection type (acute versus chronic), systemic host grade, and local extremity grade.

Methods: The initial treatment plan was a two-stage resection followed by reimplantation if clinically indicated. Treatment was modified for each patient according to how the patient responded to initial debridement. The average follow-up was 23.2 months (range, 0–74 months). Of the 50 patients, 29 had reimplantation with a total hip arthroplasty (58%), 17 patients had permanent resections (34%), and four patients had amputations (8%). Five patients died (10%). Fifteen patients had muscle flap transfers into the hip for soft tissue coverage.

Results: Significant correlations were seen with the staging system and outcome parameters. Patients who were very medically ill were far more likely to die or have their leg amputated. Conversely, healthier patients were more likely to have successful reimplantation. A strong correlation was seen with a compromised local wound and the need for muscle. ap transfer. Complication rates were strongly related to worsening medical condition and a worsening local wound.

Conclusion: Based on these results, a staging system for periprosthetic infection is a useful tool that with additional refinement will provide more objective evaluation of treatment methods for periprosthetic hip infection in the future.

Aim: To present the experience of a highly specialized total knee arthroplasty revision center with the use of femoral and tibial components with modular press-fit offset stem extensions.

Methods: Intramedullary press-fit offset stem extensions were developed to offer an additional option when doing a revision total knee arthroplasty in the presence of periarticular bone loss. The radiological and clinical results of a cohort of 28 patients that had been previously subjected to a revision total knee arthroplasty utilizing modular press-fit offset stem extensions, were studied. Mean follow-up time of these patients was 3.5 years (range, 2–7 years). The NexGen Legacy Knee System was used in all our patients (25% LCCK, 75% LPS). The use of bone cement was restricted to the femoral and tibial articular surfaces only, without any intra-medullary use.

Results: Femoral intramedullary fit and fill was measured 87.9% in anteroposterior x-rays and 85.5% in laterals. Tibial intramedullary fit and fill was measured 94.5% in anteroposterior x-rays and 89.9% in laterals. Femoral components were implanted in 6.4 degrees of valgus angle (mean values) and 2.5 degrees of flexion (mean values). Tibial components were implanted in 2.2 degrees of valgus angle (mean values) and 3 degrees of posterior slope (mean values). Knee Society Score was 89.5 points, while Function Score was 84.8. One year post-revision follow-up evaluation revealed 89% satisfaction rate among these patients.

Conclusion: The use of these press-fit offset stem extensions, with the best possible intramedullary femoral and tibial fit and fill, offer a very rewarding method and an alternative option to deal with complex reconstructive problems during a revision total knee arthroplasty.

Aim of the study: Compromised patellar bone stock poses significant technical challenges in knee revision surgery. The alternatives that have been proposed include reinsertion of a biconvex patellar component, patellar bone grafting, patellectomy, and leaving the unresurfaced patellar bone remnant in place. Various results have been reported with these methods, but not one of them has yet been widely accepted.

Methods: A novel sagittal osteotomy that was used in four patients is described.

Results: This osteotomy leaves the extensor mechanism intact and allows the medial and lateral halves of the residual patella to hinge open in the shape of a “gull wing.” This conforms to the femoral trochlear groove and when combined with particulate bone grafts, it consolidates as a mass resembling a patella.

Conclusion: The procedure has been limited to severe cases and obviates the need for patellectomy.