Arthroscopic subacromial decompression for subacromial shoulder pain (CSAW): a multicentre, pragmatic, parallel group, placebo-controlled, three-group, randomised surgical trial

Background Arthroscopic sub-acromial decompression (decompressing the sub-acromial space by removing bone spurs and soft tissue arthroscopically) is a common surgery for subacromial shoulder pain, but its effectiveness is uncertain. We did a study to assess its effectiveness and to investigate the mechanism for surgical decompression. Methods We did a multicentre, randomised, pragmatic, parallel group, placebo-controlled, three-group trial at 32 hospitals in the UK with 51 surgeons. Participants were patients who had subacromial pain for at least 3 months with intact rotator cuff tendons, were eligible for arthroscopic surgery, and had previously completed a non-operative management programme that included exercise therapy and at least one steroid injection. Exclusion criteria included a full-thickness torn rotator cuff. We randomly assigned participants (1:1:1) to arthroscopic subacromial decompression, investigational arthroscopy only, or no treatment (attendance of one reassessment appointment with a specialist shoulder clinician 3 months after study entry, but no intervention). Arthroscopy only was a placebo as the essential surgical element (bone and soft tissue removal) was omitted. We did the randomisation with a computer-generated minimisation system. In the surgical intervention groups, patients were not told which type of surgery they were receiving (to ensure masking). Patients were followed up at 6 months and 1 year after randomisation; surgeons coordinated their waiting lists to schedule surgeries as close as possible to randomisation. The primary outcome was the Oxford Shoulder Score (0 [worst] to 48 [best]) at 6 months, analysed by intention to treat. The sample size calculation was based upon a target difference of 4·5 points (SD 9·0). This trial has been registered at ClinicalTrials.gov, number NCT01623011. Findings Between Sept 14, 2012, and June 16, 2015, we randomly assigned 313 patients to treatment groups (106 to decompression surgery, 103 to arthroscopy only, and 104 to no treatment). 24 [23%], 43 [42%], and 12 [12%] of the decompression, arthroscopy only, and no treatment groups, respectively, did not receive their assigned treatment by 6 months. At 6 months, data for the Oxford Shoulder Score were available for 90 patients assigned to decompression, 94 to arthroscopy, and 90 to no treatment. Mean Oxford Shoulder Score did not differ between the two surgical groups at 6 months (decompression mean 32·7 points [SD 11·6] vs arthroscopy mean 34·2 points [9·2]; mean difference −1·3 points (95% CI −3·9 to 1·3, p=0·3141). Both surgical groups showed a small benefit over no treatment (mean 29·4 points [SD 11·9], mean difference vs decompression 2·8 points [95% CI 0·5–5·2], p=0·0186; mean difference vs arthroscopy 4·2 [1·8–6·6], p=0·0014) but these differences were not clinically important. There were six study-related complications that were all frozen shoulders (in two patients in each group). Interpretation Surgical groups had better outcomes for shoulder pain and function compared with no treatment but this difference was not clinically important. Additionally, surgical decompression appeared to offer no extra benefit over arthroscopy only. The difference between the surgical groups and no treatment might be the result of, for instance, a placebo effect or postoperative physiotherapy. The findings question the value of this operation for these indications, and this should be communicated to patients during the shared treatment decision-making process. Funding Arthritis Research UK, the National Institute for Health Research Biomedical Research Centre, and the Royal College of Surgeons (England)

Is there a difference in outcome of arthroscopic iliac crest autograft and allograft in recurrent anterior shoulder instability?

OBJECTIVE The aim of this study was to compare outcomes of arthroscopic tricortical iliac crest autograft and allograft bone blocks for recurrent traumatic anterior shoulder instability in terms of bone resorption, union and recurrent instability and assess which one is a better graft choice. PATIENTS AND METHODS Twenty-two consecutive patients treated for recurrent traumatic anterior shoulder instability that required reconstruction with bone block were included in the study. Surgical reconstruction was carried out arthroscopically with contoured tricortical iliac crest autograft or allograft. At follow-up, patients were assessed for Oxford Shoulder Instability Score (OSIS), recurrent dislocation, apprehension testing, complications, and 3-dimensional computed tomography (CT) for resorption and union rate at a mean of 10.89 months. RESULTS There were 10 patients in the allograft group with a median age of 27.7 years and a mean follow-up of 26.6 months. In the autograft group, there were 12 patients with a median age of 29 years and a mean follow-up of 28.7 months. The OSIS increased in both groups but was significantly higher in the autograft group (54.1 vs 48.2, p = 0.02). There were 2 failures in each group but no hardware complications. Allograft had higher resorption rate in comparison (75% in allograft vs 40% in autograft) and higher non-union rate (62.5% in allograft vs 16.5% in autograft). CONCLUSION This study demonstrated that both tricortical iliac crest autograft and allograft can improve shoulder instability symptoms. However, the results suggest that autograft may lead to significantly improved instability score, higher union rate and less bone resorption. LEVEL OF EVIDENCE IV, retrospective study