SUBACROMIAL PLICA AS A CAUSE OF IMPINGEMENT IN THE SHOULDER
Authors: L Funk, O Levy, T Even, and SA Copeland
References: J Bone Joint Surg Br Proceedings, Apr 2003; 85-B: 72.
Purpose: The Subacromial bursa is the largest bursa in the body. In 1934 Codman described the presence of Subacromial plicae, similar to the suprapatellar plicae found in the knee. This anatomical finding was again described by Strizak et al. in 1982. It is recognised that plicae in the knee can cause anterior knee pain with impingement against the patella in young people. We investigate the possibility that a similar situation exists with plicae of the Subacromial bursa. The aims of this study were to document the incidence of bursal plicae seen at bursoscopy during arthroscopic Subacromial decompressions of the shoulder, and to assess whether there is any pattern to the occurrence of these plicae, and the relation to impingement lesions seen at bursoscopy.
Methods: A review of all patients undergoing Arthroscopic Subacromial Decompression (ASD) of the shoulder between January 1996 and July 2001.
Results: A total of 2043 ASD procedures were performed in the study period. Of these, the number of plicae found was 130, with an incidence of 6.4%. There was a strong age predilection, with a significantly higher incidence in younger age groups. There was no difference between males and females.
Where a plica was present the impingement lesion seen on the cuff side was significantly greater than the lesion seen on the acromial side (p<0.0001). This suggests that the impingement might be due to the plica itself.
Conclusions: This study is the first to describe the presence of Subacromial plicae in living subjects and correlates with previous anatomical studies. The younger age predominance correlates with the findings of plicae in the knee. Our findings suggest that Subacromial plica may be a cause of impingement in young patients.