Trapezius muscle transfer for external shoulder rotation: anatomical study

Area of Science:

• Orthopedic surgery
• Musculoskeletal research
• Anatomical studies

Background:

• Rotator cuff tears often require tendon transfer for functional restoration.
• The trapezius muscle is a potential autograft for shoulder reconstruction.
• Optimizing trapezius transfer techniques is crucial for successful outcomes.

Purpose of the Study:

• To evaluate the suture viability of three distinct trapezius muscle transfer techniques to the greater tuberosity.
• To assess the integrity of the accessory nerve during these transfers.

Main Methods:

• Twelve cadaveric shoulders were utilized for the study.
• Three transfer techniques were performed: lower and transverse trapezius distal insertion (Group 1), lower trapezius alone (Group 2), and lower trapezius origin and insertion (Group 3).
• Suture viability and accessory nerve integrity were assessed post-transfer.

Main Results:

• Suture viability was observed in 42% of Group 1 and 58% of Group 3 transfers, with no significant difference.
• Group 3 transfers frequently resulted in neurologic injury (11/12 shoulders).
• Group 2 transfers were unsuccessful, with tendons failing to reach the greater tuberosity and no viable sutures.

Conclusions:

• Transfers involving the lower and transverse trapezius (Group 1) and the lower trapezius with origin and insertion (Group 3) demonstrated the best suture viability.
• Group 3 transfers carry a high risk of spinal accessory nerve injury.
• Further research is needed to refine trapezius transfer techniques for rotator cuff reconstruction.