Arthroscopic repair of isolated subscapularis tears: clinical outcome and structural integrity with a minimum follow-up of 4.6 years

Abstract

After isolated subscapularis repair, improvement in shoulder function has been reported at short-term review. The purpose of this study was to determine whether arthroscopic subscapularis repair provides durable improvement in objective and subjective shoulder function with a low structural retear rate. All patients treated with arthroscopic repair of an isolated subscapularis tear between August 2003 and December 2012 with a minimum follow-up period of 4.6 years were identified from our database. A number of patients in our study cohort underwent a prior complete midterm assessment, which allowed a subgroup analysis to detect changes in structural integrity and corresponding function. Clinical and radiographic outcomes, including outcomes on conventional radiography and magnetic resonance imaging or ultrasound, were assessed. The study enrolled 36 shoulders with a mean patient age of 57.7 years (range, 31-75 years; standard deviation, 10.6 years). The mean follow-up period was 8.6 years (range, 4.6-13.9 years; standard deviation, 2.44 years). Internal rotation to the thoracic vertebrae was achieved in 94% of cases and was significantly improved (P < .001) compared with the preoperativesituation. The mean relative Constant score improved from 68% preoperatively to 93% at final follow-up (P < .001). Magnetic resonance imaging evaluation showed a rerupture rate of 2.7% (1 of 36 shoulders). Twenty patients underwent previous complete midterm assessment (mean, 2.9 years; range, 1-4.5 years), with comparisons between midterm and long-term follow-up showing comparable results without statistically significant deterioration. Functional and subjective improvements in shoulder function are maintained at a mean follow-up of more than 8 years after isolated subscapularis repair and are associated with a low structural failure rate of the repair.