The benefit of open stabilization for recurrent shoulder instability is well known, however there have been recent reports of postoperative dysfunction of the subscapularis tendon following open shoulder surgery (Habermeyer et al, Scheibel et al). We present our findings in patients who have undergone an open anterior stabilization using a subscapularis split approach.

We reviewed 48 patients (49 shoulders), who were treated by the senior author (SB) from 2003–2005. They all underwent an open anterior stabilization of shoulder through a deltopectoral approach, with a subscapularis split technique, without any lateral tendon detachment. The minimum follow-up was 2 years, with average 34 months. Thirty-eight shoulders underwent an isolated anterior stabilization (1 bilateral) and 11 patients had additional procedures (8 bone grafts, 1 SLAP repair, 1 cuff repair, 1 anterior and posterior repair). There were 41 male and 7 female patients, and the mean age was 23.9 years (range 15–47 years). All patients were involved in sports and 45 had presented with recurrent dislocations. Patients were followed up using the Oxford instability score and the Rowe score questionnaires. All had a clinical examination for range of movement, stability, subscapularis muscle function, or signs of dysfunction. All had a MRI to assess the quality of the subscapularis muscle and tendon.

Mean postoperative Oxford instability score was 22.5 and the Rowe score was 69.38. Two patients had redislocated following re-injury. There was no evidence clinically of subscapularis dysfunction and the muscle and tendon were normal on all MRI scans. External rotation was reduced by a mean of 15.6 degrees. There was no significant loss of flexion or abduction. 81% of patients returned to their previous level of sport.

With a subscapularis split technique for anterior shoulder stabilization there is no significant postoperative dysfunction or damage to the subscapularis muscle, and most patients return to their previous level of sport.

The National Institute for Clinical Excellence (NICE), in its “Guidance on the Selection of Prostheses for Primary Total Hip Replacement”, states that a revision rate of 10% or less at ten years should be regarded as the “benchmark” in the selection of prostheses for primary Total Hip Replacement (THR). This paper presents the results of such a study for primary Charnley THR. Methods: All patients undergoing primary Charnley THR during 1990 were prospectively registered with the Trent Regional Arthroplasty Study (TRAS). During 1990, 1198 Charnley THRs were performed on 1152 patients, under the care of 56 consultants, in 18 National Health Service and 6 private hospitals. The cohort contains 39.0% male and 61.0% female patients, with an average age at operation of 69.1years (21–103 years), 19.1% being less than 60 years. At 10 years all surviving patients at 5 years were registered with the ONS to ascertain living patients. These patients were contacted by letter to determine whether or not their THR had been revised. The status of the THR, for non-responding patients, was determined by contacting the patient’s GP through the Contractor Services Agency (CSA). The endpoint was defined as revision surgery to replace an original implant component. Results: At 10 years, the recipients of 438 THRs had died. The recipients of 89 THRs did not respond to the questionnaire at ten years. Implant status at ten years, in living patients was known for 671 of 760 (88.3%) THRs. The ten-year crude revision rate was 44 out of 1198 (3.7%) and cumulative survival rate was 95.5% (95% CI, 93.6% – 96.9%).

Conclusion: This is the first study to assess the survivorship at 10 years for primary Charnley THRs performed in the ‘general setting’ of the NHS as opposed to specialist centres and shows a result well within the NICE benchmark.

Introduction: The National Institute for Clinical Excellence (NICE), in its “Guidance on the Selection of Prostheses for Primary Total Hip Replacement”, states that a revision rate of 10% or less at ten years should be regarded as the “benchmark” in the selection of prostheses for primary Total Hip Replacement (THR). Furthermore, they state that evidence for this, in relation to a particular prosthesis, should relate to data from a number of centres, obtained via adequately sized, well conducted observational studies, preferably with consecutive patients from non selected populations. Aim: This paper presents the results of such a study for primary Charnley THR. Methods: All patients undergoing primary Charnley THR during 1990 where prospectively registered with the Trent Regional Arthroplasty Study (TRAS). During 1990, 1198 Charnley THRs were performed on 1152 patients, under the care of 56 consultants, in 18 national health service and 6 private hospitals. The cohort contains 39.0 % male and 61.0 % female patients, with an average age at operation of 69.1years (21–103 years). At 10 years all surviving patients at 5 years were registered with the ONS to ascertain living patients. These patients were contacted by letter to determine whether or not their THR had been revised. The status of the THR, for non-responding patients, was determined by contacting the patient’s GP through the Contractor Services Agency (CSA). Survival analysis was performed using life table analysis as described by Armitage and Berry and the endpoint was defined as revision surgery to replace an original implant component. Results: At 10 years, the recipients of 246 THRs had died. The recipients of 86 THRs did not respond to the questionnaire at ten years. There was no follow–up data on 42 implants at both 5 and 10 years intervals. Thus, implant status at five or ten years, in living patients was known for 910 of 952 (95.6%) THRs. The ten-year crude revision rate was 43 out of 1198 (3.59%) and cumulative survival rate was 95.4% (95% CI, 93.2% – 96.9%). Conclusion: This is the first study to assess the survivorship at 10 years for primary Charnley THRs performed in the “general setting“ of the NHS as opposed to specialist centres and shows a result well within the NICE benchmark.

Cementation is an important part of arthroplasty operations. Recent publication of results of Charnley total hip replacement found a rate of early aseptic loosening of 2.3% at 5 years following surgery across a NHS region. There are possibly many reasons for early loosening but precise reasons are still not fully understood, however, it is felt that cementation technique is very important. There seems to be a number of factors involved such as cement mixing techniques and conditions, physical properties of the cement, cementation and surgical techniques, bone-cement interface as well as bone- prosthesis interface. The purpose of this study was to evaluate the effectiveness of the clinical environment in producing bone cement of predictable mechanical and physical properties, and how those properties compare with published data. The investigation compared samples of bone cement, taken from material prepared and used in surgery with cement samples prepared under controlled laboratory conditions and in accordance with ISO materials testing standards.

During 2000–01, 10 total hip replacements were selected for study. All operations involved the use of CMW1 (DePuy) radio-opaque cement, which was mixed using the Vacumix system. In this cohort, all femoral cementations were performed using an 80g cement mix. After careful preparation of the femoral canal, the scrub nurse mixed the cement in accordance with the manufacturer’s instructions. The cement was introduced into the femoral canal, via a nozzle, using the cementation gun and a pressurizer. Following introduction of cement into the canal, the nozzle and cement contained within, was broken off the gun distal to the pressurizer. Once cured, the cement samples were removed from the nozzle, sectioned, and mechanically tested. Due to this novel sample preparation procedure, the tested cement was expected to exhibit mechanical and physical properties characteristic of the cement present in the femoral canal. Samples of CMW1 (Vacumixed) of similar mass and aspect ratio were produced within the laboratory, in accordance with the manufacturers mixing instructions. PMMA bone cement is a brittle, glassy polymer that is susceptible to stress raisers, such as pores, which can reduce the load carrying ability, which in vivo is predominantly compressive in nature. Published mechanical properties of PMMA bone cement vary somewhat, reflecting the dependence of properties on flaw distribution. The density, which provides a measure of porosity, hardness and ultimate compressive strength of the cement samples was measured and compared.

The surgical samples were found to be very consistent in compressive strength (121 ± 6 MPa), density (1.20 ± 0.02 gcm⁻³) and hardness (23.2 ± 1.6 VHN) and closely matched the mechanical properties of the cement mixed in the laboratory.

This study suggests that for the studied cement and mixing regime, the clinical environment is capable of producing a well-controlled cement product that has reproducible and predictable mechanical properties. Further, the novel sample preparation procedure used suggests that the cement within the femoral cavity should demonstrate equally predictable, mechanical and physical properties.