Anterior deltoid muscle reflection using a deltopectoral approach is safe and does not influence outcome of reverse shoulder arthroplasty.

Abstract

The deltopectoral approach is well accepted for shoulder arthroplasty procedures. The extended deltopectoral approach with detachment of the anterior deltoid from the clavicle allows increased joint exposure and can protect the anterior deltoid from traction injury. The efficacy of this extended approach has been demonstrated in anatomical total shoulder replacement surgery. However, this has not been shown in reverse shoulder arthroplasty (RSA). The primary aim of this study was to evaluate the safety of the extended deltopectoral approach in RSA. The secondary aim was to evaluate the performance of the deltoid reflection approach in terms of complications, surgical, functional and radiological outcomes up to 24 months post-surgery. A prospective non-randomized comparative study was performed between January 2012 and October 2020 including 77 patients in the deltoid reflection group and 73 patients in the comparative group. Decision for inclusion was based on patient and surgeon factors. Complications were recorded. Patients were followed up for at least 24 months to evaluate their shoulder function and ultrasound evaluation. Functional outcome measures included the Oxford Shoulder Score (OSS), Disabilities of the Arm, Shoulder and Hand (DASH) score, American Shoulder Elbow Surgeons score (ASES), pain intensity (VAS 0-100), range of motion (forward flexion (FF), abduction (AD), and external rotation (ER)). A regression analysis was performed to evaluate any factors of influence on the VAS. There were no significant differences in the rate of complications between the two groups (14.5% in the deltoid reflection group and 13.8% in the comparative group, p=0.915). Ultrasound evaluation was available in 64 (83.1%) patients, and no proximal detachment was observed. In addition, there were no significant differences in functional outcome measures both preoperatively and at 24 months post-surgery between the groups on Mean VAS pain, OSS, DASH, ASES, FF, ABD, and ER. Adjustment for possible confounders in a regression model indicated that only prior surgery significantly influenced the VAS pain (p=0.031, 95%CI 0.574 - 11.67) after surgery. Deltoid reflection (p=0.068), age (p=0.466), sex (p=0.936), glenoid graft (p=0.091), prosthesis manufacturer (p=0.382) and preop VAS score (p=0.362) were not of influence. Results of this study show an extended deltopectoral approach for RSA is safe. Selected reflection of the anterior deltoid muscle improved exposure and prevents anterior deltoid muscle injury followed by re-attachment. Patients had similar functional scores preop and at 24 months compared to a comparative group. Furthermore, ultrasound evaluation showed intact re-attachments.