Pigmented villonodular synovitis of the shoulder associated with massive rotator cuff tear treated with arthoroscopic synovectomy and debridement.

Introduction Pigmented villonodular synovitis (PVNS) is a rare condition. We present the largest series of patients with shoulder PVNS, massive irreparable rotator cuff tear and gleno-humeral osteoarthritis treated with arthroscopic debridement and synovectomy. Materials and methods We treated 9 patients (6F and 3 M, mean age 65.8 years, range 63–70 years) with PVNS of the shoulder; irreparable rotator cuff tear and slight gleno-humeral arthropathy (group I). Patients underwent arthroscopic synovectomy and debridement. Results were compared with those obtained from a control group (group II) made up of 33 consecutive patients (21F and 12 M) who underwent arthroscopic debridement for irreparable cuff tear and had no (23 patients) or slight (10 patients) gleno-humeral arthropathy (Constant Score). Results The preoperative shoulder function in group I was reduced with respect to group II (CS: 12 vs. 35). Upon follow-up the CS value was lower in group I than in group II (CS: 40 vs. 54). In the preoperative period, the differences between the two groups relating to the CS value and to each item of the score were always statistically significant; instead, upon follow-up, significant differences emerged in the CS value, ADL and ROM. Differences relative to pre-operative CS values in group I and II were statistically significant; while, at the follow-up period, significant differences emerged only between CS values of patients with PVNS and the values of group II without gleno-humeral arthropathy. No differences emerged between pre and post-operative CS values in group II without or with gleno-humeral arthropathy. Discussion PVNS of the shoulder is a rare condition. Recent literature refers on sporadic case reports which affected above all middle aged or elderly patients. Only two papers described respectively of one case of PVNS of the shoulder that occurred in two adolescent males. Conclusions Arthroscopic synovectomy is an effective surgical treatment for PVNS; the poor functional outcome can be attributed to the coexistence of the gleno-humeral arthropathy. Three fourths of patients with PVNS had shoulder osteoarthritis; this percentage cannot be simply attributed to natural history of massive irreparable cuff tears; but a direct role of synovitis has to be considered.