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Updated: Jul 20, 2026
Reverse Total Shoulder Arthroplasty
Published on: July 5, 2011
Influence of the rotator cuff tear pattern in shoulder stability after arthroscopic superior capsule reconstruction:
Madalena Antunes1, Carlos Quental1, João Folgado1
1IDMEC, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001, Lisbon, Portugal.
Objectives:
To assess the ability of the arthroscopic superior capsule reconstruction (SCR) in restoring glenohumeral stability in the presence of different preoperative patterns of irreparable rotator cuff tears (RCTs).
Methods:
A computational musculoskeletal (MSK) model of the upper limb was used to simulate isolated SCR and to estimate the stability of the shoulder. Four patterns of preoperative irreparable RCTs were modeled: Supraspinatus (SSP); SSP + Subscapularis (SSC); SSP + Infraspinatus (ISP); and SSP + SSC + ISP. The muscles involved in the irreparable RCT were removed from the MSK model to simulate an irreparable full-thickness tear. In the MSK model, the muscle and joint forces were estimated for a set of upper limb positions, from four types of motions (abduction in the frontal plane, forward flexion in the sagittal plane, reaching behind the back, and combing the hair) collected in a biomechanics laboratory, through inverse dynamic analysis. The stability of the shoulder was estimated based on the tangential and compressive components of the glenohumeral joint reaction force. The comparison of pre- and post-operative conditions, for the four patterns of irreparable RCTs, with the healthy condition, was performed using ANOVA and Tukey's tests (statistical level of p < 0.05).
Results:
In the setting of an isolated irreparable SSP tear, SCR statistically significantly improved stability compared with the preoperative condition (p < 0.001). For the irreparable SSP + SSC pattern, a statistically significant loss in stability was observed (p < 0.001) when SCR was applied. For the irreparable SSP + ISP and SSP + SSC + ISP patterns, the postoperative condition increased shoulder stability, compared to the preoperative condition; however, the improvement was not statistically significantly different.
Conclusion:
Isolated SCR for irreparable RCTs extending beyond the SSP does not statistically significantly improve the stability of the glenohumeral joint.
Level Of Evidence:
Level IV.
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