Return To Sport Testing At 6 Months After Arthroscopic Shoulder Stabilization Demonstrates Residual Functional Deficits

Objectives: A good outcome after arthroscopic stabilization for recurrent shoulder instability is often characterized by a successful return to sport while minimizing complications. While many physicians use a minimum of 5 months as a time to return, there is currently no consensus regarding timing or objective criteria for return to sport. The objective of this study is to evaluate the ability of postoperative patients to meet expected goals of achieving appropriate strength and using standardized objective evaluations of strength and physical function. Methods: 33 consecutive patients who underwent arthroscopic shoulder stabilization surgery from 2012 until 2018 and completed their postoperative rehabilitation with the same institution were subjected to functional testing to evaluate their readiness for return to sport. Isometric unilateral external rotation to internal rotation (ER/IR) ratio was measured using a hand held dynamometer at 0 and 90 degrees of shoulder abduction. Posterior rotator cuff activation was evaluated using a repetition to failure technique with 5% body weight at 0 and 90 degrees of abduction. Prone trapezius activation was measured in repetitions to failure with a prone Y exercise. A subset of throwing athletes (N= 11) were evaluated for total arc of motion. Results: Isometric testing at revealed that 18% (6/33, mean ratio 71%) patients met the expected goal of 80% ER/IR strength at both 0 and 90 degrees of abduction, with mean ratios of 71% and 62%, respectively. 73% (24/33) and 42% (14/33) of patients met goal of 90% of the contralateral ER repetitions to failure in rotator cuff activation testing at 0 and 90 degress of abduction, respectively. 55% (18/33) of patients met goal of 90% of contralateral prone Y repetitions to failure on lower trapezius activation testing, with mean. Mean total arc of postoperative motion for the 11 throwers was 91.6% of the contralateral shoulder. Thirty-six percent (4/11) patients did not reach 90% of the total arc of motion of the uninvolved shoulder. Conclusion: A substantial number of athletes in our cohort do not meet the expected goals for their operative shoulder in achieving appropriate strength, particularly in ER, nor arc of motion compared to the contralateral shoulder.