Abstract
Purpose: To evaluate the use of a steroid and local anaesthetic subacromial injection as a prognostic tool for patient recovery following arthroscopic subacromial decompression (ASD).
Methods: A prospective study of all patients seen in our unit with a clinical diagnosis of subacromial impingement syndrome was carried out between 1/00 and 9/01. All patients were diagnosed clinically, followed by a local anaesthetic/steroid subacromial injection test. In the event of a negative result to the injection test, the diagnosis was confirmed by CT arthrography or MRI scanning. All patients underwent standard ASD, with clinical evaluation via the Constant score preoperatively, at 3 weeks, 3 months, and at discharge. The eventual functional outcome was correlated with the results of the impingement test and the operative findings.
Results: One hundred and one patients (53 male, 48 female), with a mean age of 52 years (range 21–77) were entered into the study. Patients were followed up for a mean of 14 months (range 3–24). All patients had an impingement lesion noted at arthroscopy. The mean preoperative Constant score for the entire group was 48 (20–67) with a postoperative mean of 81 (46–98). 16 patients had a negative preoperative injection test. The mean improvement in this group was 21 points (47 rising to 68) compared to 35 points (48 to 83) in the positive group (p< 0.05, Mann-Whitney U test). The groups were otherwise similar for age, sex and operative findings.
Conclusions: The subacromial injection test is a useful tool both diagnostically and prognostically in patients with subacromial impingement syndrome. In patients with a confirmed diagnosis but a negative test there is still a significant improvement in the post operative Constant score, but this is of a lesser degree than in those with a positive injection test. This does not appear to be related to age, impingement grade or cuff tears, and may represent a true difference in the underlying pathology.
The abstracts were prepared by David Stanley. Correspondence should be addressed to him c/o British Orthopaedic Association, Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PN.
