Timing of retears after arthroscopic rotator cuff repair and associated factors: a retrospective analysis.

Abstract

Retear after arthroscopic rotator cuff repair (ARCR) remains a complication of important concern. Few reports have evaluated retear timing and its associated patient characteristics in large cohorts. This study aimed to investigate retear timing and patient characteristics and factors associated with this parameter. Of the 638 consecutive shoulders that underwent ARCR from August 2009 to November 2019, shoulders with retear complication within 1year of surgery were included. Retears were defined as type IV or V of the Sugaya's classification, and magnetic resonance imaging was performed at 6weeks, 3months, 6months, and 1year after surgery. The distribution of patients with retears at the timing of retears was investigated. In addition, patients with retears were classified into the following two groups: early group with retears occurring at 6weeks and 3months postoperatively or late group with retears occurring between 6months and 1year postoperatively. Associated factors such as sex, age, tear size, pre and postoperative range of motion, surgical technique, and clinical outcome between the two groups were investigated. The 41 shoulders with retears were divided into four groups: 1) within 6weeks after surgery (n=9, 22.0%), 2) 6weeks-to 3months after surgery (n=19, 46.3%), 3) 3-6months after surgery (n=11, 26.8%), and 4) 6months-1year after surgery (n=2, 4.9%). In addition, there were significantly larger retear sizes in the Sugaya's classification in the early group compared to the late group (P=.013), while there were significantly more males in the late group compared to the early group (P=.030). The highest retear rate after ARCR was observed from 6weeks to 3months after surgery, with equivalent rates within 6weeks and from 3months to 6months after surgery.