Commentary & Perspective

Commentary & Perspective on
"Arthroscopic Acromioplasty: A Comparison Between Workers' Compensation and Non-Workers' Compensation Populations"
by Gregory P. Nicholson, MD, et al.

Commentary & Perspective by
Ken Yamaguchi, MD*,
Shoulder and Elbow Service, Washington University School of Medicine, St. Louis, MO

In this issue of The Journal, Nicholson describes a prospective study of 106 consecutive patients with a diagnosis of primary subacromial impingement syndrome who were treated with arthroscopic acromioplasty performed by a single surgeon. The outcomes in a group of forty patients (forty shoulders) with Workers' Compensation were directly compared with those in sixty-six patients (sixty-six shoulders) who did not have Workers' Compensation. In contrast to previous studies that compared populations of patients with and without Workers' Compensation who underwent arthroscopic subacromial decompression, this author also included the effects of the work-demand level and the presence of intra-articular shoulder pathology as clinical variables that could affect outcomes in the two groups^1-3.

Nicholson showed that, regardless of a patient's Workers' Compensation status, an excellent outcome can be expected from arthroscopic acromioplasty for the treatment of subacromial impingement syndrome. The mean American Shoulder and Elbow Surgeons score for the entire population improved significantly from 41.8 to 86.9 (p = 0.0001); the average score on the Simple Shoulder Test improved from 5.1 to 10.0; and the average score on the visual analog scale for pain improved from 6.0 to 1.1. There was no significant difference in the mean outcome scores between the Workers' Compensation and non-Workers' Compensation groups. Importantly, there was a significant difference in the average time to return to full-duty work (p = 0.0001), with patients in the Workers' Compensation group requiring an average of 13.7 weeks compared with an average of 9.1 weeks for those in the non-Workers' Compensation group; however, this longer return-to-work time reflected the heavier work-demand level of the patients in the Workers' Compensation group, both preoperatively and postoperatively, in comparison with those in the non-Workers' Compensation group. Work-demand level, in fact, had a significant effect on time to return to work (p = 0.0025) in the entire study group. The patients in the sedentary work-demand category required an average of only 6.17 weeks to return to work in comparison with those in the heavy work-demand category, who required an average of 14.29 weeks (p= 0.014). Intraoperative pathology was not significantly different between the two groups and did not correlate with the outcome scores.

This clearly written study offers several important observations that can be helpful in the evaluation and treatment of patients with subacromial impingement syndrome:

1. Arthroscopic acromioplasty can be a highly successful procedure when it is performed by an experienced surgeon and indications for the procedure are based on strict and appropriate preoperative criteria.
2. With strict criteria for operative intervention, patients with Workers' Compensation can have as good a prognosis as those without Workers' Compensation; however, realistic expectations of the time to return to work should be determined according to the projected work-demand level.
3. These guidelines can be used to counsel patients and to inform insurance carriers, employers, and caregivers of a patient's time to return to work. It should be noted that those values given in this paper for return-to-work time—for instance, averages of 12.5 weeks for the patients with a medium work-demand level, 12.1 weeks for those with a medium-heavy work-demand level, and 14.3 weeks for those with a heavy work-demand level—had standard deviations of approximately three to five weeks. Thus, the average patient with a heavy work-demand level can be reasonably expected to take as long as eighteen or nineteen weeks to return to full-duty work.

It is important to consider why Nicholson demonstrated such excellent results for arthroscopic acromioplasty in both of the patient groups in his study in comparison with results in the previous literature that have suggested that poorer outcomes can be expected in a Workers' Compensation population^1-3. Several factors may have been important in achieving the consistently good results reported in this study:

1. A single surgeon performed the operations with use of consistent surgical indications and consistent surgical technique. That surgeon was very experienced in shoulder surgery and can be assumed to have long overcome any "learning curve" associated with arthroscopic acromioplasty.
2. Most importantly, the indications for surgery were well defined and were appropriate for this population. All patients had to have at least one positive impingement test and many had two. Although a minimum of only three months of conservative treatment without relief of symptoms after presentation to a surgeon was a criterion, it should be noted that all patients had had substantial periods of pain prior to presentation. Another criterion was unsuccessful conservative management consisting of a surgeon-directed treatment regimen combining home and outpatient physical therapy. These strict criteria may have helped to eliminate those patients that may have had secondary gain behavior that affected their presentation of symptoms to a physician.
3. Finally, an important consideration was the surgeon's choice of treatment for associated pathology. In particular, partial-thickness tears that were identified were treated aggressively. A tear involving greater than 30% of the thickness of the rotator cuff was used as the criterion to perform a repair of the tear through a mini-open approach. Eleven patients in this series underwent full-thickness rotator-cuff repair. If débridement alone had been unsuccessful in a large proportion of these patients, it could have substantially altered the findings of this study.

In conclusion, this study by Nicholson provides very important information about a common clinical entity—subacromial impingement syndrome with rotator cuff tendinitis. The results suggest that pessimism regarding the outcome of arthroscopic acromioplasty for treatment of this syndrome in patients with Workers' Compensation is not warranted as long as there is strict adherence to appropriate surgical indications. The study also demonstrates the importance of considering work-duty status when predicting a patient's time to return to work after arthroscopic subacromial decompression.

*The author did not receive grants or outside funding in support of the research or preparation of this manuscript. He did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the author is affiliated or associated.

References

1. Frieman BG, Fenlin JM Jr. Anterior acromioplasty: effect of litigation and workers' compensation. J Shoulder Elbow Surg. 1995;4:175-81.
2. Ellman H, Kay SP. Arthroscopic subacromial decompression for chronic impingement. Two- to five-year results. J Bone Joint Surg Br. 1991;73:395-8.
3. Hawkins RJ, Plancher KD, Saddemi SR, Brezenoff LS, Moor JT. Arthroscopic subacromial decompression. J Shoulder Elbow Surg. 2001;10:225-30.