Abstract
Introduction
The conservative management of Sub-Acromial Impingement Syndrome (SAIS) of the shoulder includes both physiotherapy treatment and subacromial injection with local anaesthetic and steroids. The outcome from injection treatment has rarely been evaluated scientifically.
Methods
Patients attending a designated shoulder clinic and diagnosed by an experienced shoulder surgeon as having a SAIS between January 2009 and December 2011 were considered for inclusion in the study. 67 of 86 patients screened completed the study (3 did not meet inclusion criteria; 9 declined to participate; 3 lost to follow-up; 4 developed frozen shoulder syndrome). Each patient had a pre-injection Oxford Shoulder Score (OSS) and was given one subacromial injection of 10ml 0.25% levobupivacaine(Chirocaine) + 40 mg triamcinolone(Kenalog) through the posterior route. Radiograph imaging was also assessed. Follow-up was carried out at 6 to 12 weeks post injection when OSS was repeated. A 6 month follow-up assessment to assess if the patient's improvement in functionality and absence of symptoms indicated that a subacromial decompression operation was not necessary. The percentage of patients showing improvement in OSS was calculated and the difference in OSS pre- and post-injection assessed using a Wilcoxon Signed Rank test.
Results
The median OSS pre-injection was 29 (range 2–43) and post-injection was 40 (range 2–48) (p=< 0.001; z=−6.0; r=−0.5). 45/69 (71%) of patients benefited significantly from subacromial injection at 6 to 12 weeks post-injection. However only 28/53 (53%) benefited significantly from injection by 6 months post-injection. These results support the continued use of sub-acromial corticosteroid injections in the treatment of SAIS. 31% of these patients were subsequently treated with an arthroscopic subacromial decompression operation. Previous injection history had no impact on the results.
Conclusions
We recommend that all patients with SAIS should be offered at least one subacromial injection before being considered for an arthroscopic subacromial decompression operation.