Deficits in Upper Limb Long Lever Isometric Force After Shoulder Stabilization Surgery in Australian Rules Footballers.

Abstract

Background: Early surgical interventions are common for traumatic anterior shoulder instability in contact and collision sport athletes. It is unclear which tests, and which criteria, should be used to guide return to sport after surgery. As such, additional knowledge on postoperative shoulder function is needed to guide this decision making.

Purpose: To assess deficits in upper limb long lever isometric force and the rate of force development (RFD) in Australian rules footballers after anterior shoulder stabilization surgery.

Study design: Cross-sectional study; Level of evidence, 3.

Methods: A total of 30 male Australian rules footballers who had undergone unilateral anterior shoulder stabilization surgery were assessed at 4 to 6 months postoperatively. An uninjured age-, sex-, and sport-matched control group (n = 30) was assessed on a single occasion. Isometric peak force and RFD (within the first 100 and 200 milliseconds) were measured using the Athletic Shoulder (ASH) test in 3 positions (ISO-I, ISO-Y, and ISO-T). Data were analyzed for interlimb differences within the surgical group and between-group differences against controls. The reliability of the measurements was also assessed, and correlations between peak force and RFD were determined.

Results: In all ASH test positions, the surgical arm showed significantly lower peak force and RFD within 200 milliseconds than both the nonsurgical arm and control group (P < .05). No differences were found in the RFD within 100 milliseconds (P > .05). Large effect sizes were noted in peak force deficits between the surgical arm and control group, particularly in the ISO-T position (d = 1.19; P < .001). Interlimb asymmetries were highly variable and did not consistently favor the nonsurgical arm.

Conclusion: Australian rules footballers at 4 to 6 months after shoulder stabilization surgery exhibited significant deficits in long lever isometric force and late-phase RFD. Clinicians should be cautious in interpreting limb asymmetry and RFD measurements during return-to-sport assessments. Further research should explore the long-term outcomes and relationship between these physical measurements, patient-reported outcomes, and reinjury rates.