The incidence of stress fracture following peri-acetabular osteotomy: an under-reported complication.

Stress fractures occurring in the pubis and ischium after peri-acetabular osteotomy (PAO) are not well recognised, with a reported incidence of 2% to 3%. The purpose of this study was to analyse the incidence of stress fracture after Bernese PAO under the care of two high-volume surgeons. The study included 359 patients (48 men, 311 women) operated on at a mean age of 31.1 years (15 to 56), with a mean follow-up of 26 months (6 to 64). Complete follow-up radiographs were available for 348 patients, 64 of whom (18.4%) developed a stress fracture of the inferior pubic ramus, which was noted at a mean of 9.1 weeks (5 to 55) after surgery. Most (58; 91%) healed. In 40 of the patients with a stress fracture (62.5%), pubic nonunion also occurred. Those with a stress fracture were significantly older (mean 33.9 years (16 to 50) vs 30.5 years (15 to 56), p = 0.002) and had significantly more mean pre-operative deformity: mean centre-edge angle (9.8° (-9.5 to 35) vs 12.4° (-33 to 28), p = 0.04) and mean Tönnis angle (22.8° (0 to 45) vs 18.7° (-2 to 38), p < 0.001). The pubic nonunion rate was significantly higher in those with a stress fracture (62.5% vs 7%, p < 0.001), with regression analysis revealing that these patients had 11.8 times higher risk than those without nonunion.

Failure of a "screw-in" acetabular component: ten-year results, survivorship analysis, and the prediction of failure.

The Rotalok screw-in threaded acetabular component was prospectively reviewed with 10-year clinical and radiological follow-up for 60 patients. Nine patients died and 5 were lost to follow-up. Clinically, 28 patients were pain-free, 13 had mild pain, and 3 had moderate pain. Thirteen patients underwent revision for loosening and 3 required revision but were unfit. Superior migration, angular migration, and zone lucency were measured radiologically. Cumulative survival was 70.75% with revision surgery as the end point and 60% with combined clinical failure and revision as the end point. Angular migration of 3 degrees or more was a significant predictor of clinical failure and revision (P < .0001), with 5 degrees being very highly predictive with a sensitivity of 0.72 and a specificity of 1.00. Revision was associated with younger patients (P = .03) and autograft use without screw stabilization (P = .024). The high failure rate of the Rotalok necessitates careful clinical and radiological follow-up, with asymptomatic radiological angular migration often the first predictor of failure.

The effect of component malalignment on the clinical and radiological outcome of the Kinemax total knee replacement.

Component angles of 198 Kinemax total knee replacements were measured from standard short leg radiographs. An ideal tibio-femoral angle of between 4 and 10 degrees of valgus was achieved in 64.6% of patients. After an average follow-up of 6.5 years (range 4.5 to 9.5), there was no significant difference between knees in acceptable and suboptimal alignment in terms of pre- and post-operative knee and function scores and prevalence of radiolucent lines. Varus placement of the tibial component was significantly more common by trainee surgeons (P<0.001).

Compartment syndrome following pelvic surgery in the lithotomy position.

We report the cases of two patients who developed compartment syndrome following pelvic surgery in the lithotomy position. These cases highlight this important and potentially devastating complication.

The effect of surgeon experience on component positioning in 673 Press Fit Condylar posterior cruciate-sacrificing total knee arthroplasties.

Component angles of 673 Press Fit Condylar (PFC) total knee arthroplasties were measured from standard short-leg radiographs. The femoral and tibial resections were performed with intramedullary and extramedullary instrumentation. The mean coronal tibial component angle was 88.59 degrees (SD, 2.28 degrees; range, 78-98 degrees ), with 17.1% having values <87 degrees and 1.9% having values >93 degrees. The mean coronal femoral component angle was 97.43 degrees (SD, 3.44 degrees; range, 84-115 degrees ), with 9.1% having values <94 degrees and 13.1% having values >100 degrees. An ideal tibiofemoral angle of 4 degrees to 10 degrees of valgus was achieved in 75.3% of patients, being <4 degrees in 18.6% and >10 degrees in 6.1%. Alignment was not significantly different between consultant and trainee surgeons. Although varus positioning of the tibial component was the commonest error, the wide range of femoral component angles signifies problems with standard intramedullary femoral guides.

The intra- and inter-observer reliability of the Samilson and Prieto grading system of glenohumeral arthropathy.

Severity of glenohumeral arthropathy following shoulder instability is often graded radiologically on the basis of osteophyte size according to Samilson and Prieto. Intra- and inter-observer reliability of this popular grading system was determined using standard radiographs of 20 arthritic cadaveric humeri. Using two observers on two occasions, reliability of the grading system using the antero-posterior radiograph varied between fair and poor (kappa coefficients 0.07-0.33). This study shows that the Samilson and Prieto grading of glenohumeral arthropathy is unreliable and, in clinical use, when magnification and rotation is less easy to control, it is likely to be even more so. Another validated classification system must therefore be found.

The Kinemax total knee arthroplasty. Nine years' experience.

We reviewed the outcome of 422 primary cemented Kinemax total knee arthroplasties implanted into 369 patients over a period of five years, from January 1989. The operations were carried out at two NHS district general hospitals and one teaching hospital by 31 surgeons. During the period of review, 49 patients died and ten knees were lost to follow-up (68 knees). The mean Knee Society score improved from 28 before to 89 after surgery, and the mean function score increased from 23 to 79. The range of flexion improved from 92 degrees to 105 degrees. These improvements were maintained throughout the period of study. At the latest review radiolucent lines of 1 mm were seen around 15% of tibial components, 1.4% of patellar components and 9.5% of femoral components. In no case were these changes progressive. Using revision as the endpoint, cumulative survival was 99% after five years and 96.95% after nine years. All revisions were undertaken for deep infection or secondary trauma. Our study has shown that the Kinemax total knee replacement, when carried out with retention of the posterior cruciate ligament by surgeons of varying experience, produces very satisfactory results in the medium term.

Valgus extension osteotomy for 'hinge abduction' in Perthes' disease. Results at maturity and factors influencing the radiological outcome.

Valgus extension osteotomy (VGEO) is a salvage procedure for 'hinge abduction' in Perthes' disease. The indications for its use are pain and fixed deformity. Our study shows the clinical results at maturity of VGEO carried out in 48 children (51 hips) and the factors which influence subsequent remodelling of the hip. After a mean follow-up of ten years, total hip replacement has been carried out in four patients and arthrodesis in one. The average Iowa Hip Score in the remainder was 86 (54 to 100). Favourable remodelling of the femoral head was seen in 12 hips. This was associated with three factors at surgery; younger age (p = 0.009), the phase of reossification (p = 0.05) and an open triradiate cartilage (p = 0.0007). Our study has shown that, in the short term, VGEO relieves pain and corrects deformity; as growth proceeds it may produce useful remodelling in this worst affected subgroup of children with Perthes' disease.

How long should patients be followed-up after total hip replacement? Current practice in the UK.

Some 1000 postcard questionnaires were sent to Fellows of the British Orthopaedic Association (BOA) to establish current follow-up practice of primary total hip replacement (THR) patients. For cemented THRs, 50% of surgeons saw their patients for under 1 year, 78% under 5 years with indefinite follow-up being performed by 14%. There was significantly more follow-up of uncemented and hybrid prostheses with the proportions being 25%, 56% and 30% respectively (chi 2, P < 0.0001). This study has revealed a wide variation in practice between individual surgeons and has shown over one-third of surgeons feel they are prevented from performing as much follow-up as they would wish by the availability of clinic resources. Higher follow-up rates of uncemented components may reflect a lack of confidence in their long-term performance.

Day-case simple extensor origin release for tennis elbow.

The results of day-case lateral release for resistant tennis elbow were evaluated in 20 patients after an average follow-up of 16 months. Using the outcome criteria of Verhaar et al. [4] an excellent result was obtained in 55%, a good result in 35% and a fair result in 10%, with all patients benefiting from surgery. We believe surgery should be offered at an earlier stage in the treatment of tennis elbow, with the simple and effective nature of the operation providing little justification for persisting with conservative treatment. With hindsight, three-quarters of our patients would have preferred earlier surgical referral.

A standard method of shoulder strength measurement for the Constant score with a spring balance.

The strength component of the Constant score has been criticized for its lack of a precisely defined measurement method. A series of experiments was performed to compare three different methods in normal and pathologic shoulders with the use of a standard test position. These were (1) the Isobex isometric dynamometer, (2) Constant's unsecured spring balance, and (3) a new modification in which the spring balance is fixed at one end and the reading is taken after 5 seconds of maximum effort. The results suggest that this simple modification with a low-cost spring balance can give similar values to those from the Isobex. The need for precision of terms and a definition of the method is discussed, and recommendations for the standardization of the many variables in making this measurement are made.

Pioneers of shoulder replacement: Themistocles Gluck and Jules Emile Péan.

Dr. Jules Emile Péan is widely credited with having performed the first total shoulder replacement March 11, 1893, at the Hôpital International in Paris. However, in his original report Péan refers to the work of Themistocles Gluck as being the inspiration for his shoulder prosthesis, a fact understated if not completely overlooked during the last hundred years. This article therefore attempts to reappraise the relative contributions of these two pioneering surgeons to shoulder arthroplasty.