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

Background: 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 anatomic 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 and surgical, functional, and radiologic outcomes up to 24 months after surgery. Methods: A prospective, nonrandomized 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. The decision for inclusion was based on patient and surgeon factors. Complications were recorded. Patients were followed up for ≥24 months to evaluate their shoulder function and undergo ultrasound evaluation. Functional outcome measures included the Oxford Shoulder Score, Disabilities of the Arm, Shoulder and Hand score, American Shoulder and Elbow Surgeons score, pain intensity (rated on visual analog scale [VAS] from 0 to 100), and range of motion (forward flexion, abduction, and external rotation). A regression analysis was performed to evaluate any factors of influence on the VAS score. Results: There were no significant differences in the complication rate between the 2 groups (14.5% in deltoid reflection group and 13.8% in comparative group, P = .915). Ultrasound evaluation was available in 64 patients (83.1%), and no proximal detachment was observed. In addition, there were no significant differences in functional outcome measures both preoperatively and at 24 months after surgery between the groups assessed based on the mean VAS pain score, Oxford Shoulder Score, Disabilities of the Arm, Shoulder and Hand score, American Shoulder and Elbow Surgeons score, forward flexion, abduction, and external rotation. Adjustment for possible confounders in a regression model indicated that only prior surgery significantly influenced the VAS pain score after surgery (P = .031; 95% confidence interval, 0.574-11.67). Deltoid reflection (P = .068), age (P = .466), sex (P = .936), use of glenoid graft (P = .091), prosthesis manufacturer (P = .382), and preoperative VAS score (P = .362) were not of influence. Discussion: The results of this study show that an extended deltopectoral approach for RSA is safe. Selected reflection of the anterior deltoid muscle improved exposure and prevented anterior deltoid muscle injury followed by reattachment. Patients had similar functional scores preoperatively and at 24 months postoperatively compared with a comparative group. Furthermore, ultrasound evaluation showed intact reattachments.</p

A biomechanical analysis of double-screw, double-button, and screw-button fixation constructs in patient-specific instrument–guided Latarjet procedure

Background: The Latarjet coracoid transfer procedure reliably stabilizes the glenohumeral joint for shoulder instability. However, complications such as graft osteolysis, nonunion and fracture continue to affect patient clinical outcomes. The double-screw (SS) construct is regarded as the gold standard method of fixation. SS constructs are associated with graft osteolysis. More recently, a double-button technique (BB) has been suggested to minimize graft-related complications. However, BB constructs are associated with fibrous nonunion. To mitigate this risk, a single screw combined with a single button (SB) construct has been proposed. It is thought that this technique incorporates the strength of the SS construct and allows micromotion superiorly to mitigate stress shielding–related graft osteolysis. Aims: The primary aim of this study was to compare the failure load of SS, BB, and SB constructs under a standardized biomechanical loading protocol. The secondary aim was to characterize the displacement of each construct throughout testing. Methods: Computed tomography scans of 20 matched-pair cadaveric scapulae were performed. Specimens were harvested and dissected free of soft tissue. SS and BB techniques were randomly assigned to specimens for matched-pair comparison with SB trials. A patient-specific instrument (PSI)–guided Latarjet procedure was performed on each scapula. Specimens were tested using a uniaxial mechanical testing device under cyclic loading (100 cycles, 1 Hz, 200 N/s) followed by a load-to-failure protocol (0.5 mm/s). Construct failure was defined by graft fracture, screw avulsion, and/or graft displacement of more than 5 mm. Results: Forty scapulae from 20 fresh frozen cadavers with a mean age of 69.3 years underwent testing. On average, SS constructs failed at 537.8 N (SD 296.8), whereas BB constructs failed at 135.1 N (SD 71.4). SB constructs required a significantly greater load to fail compared with BB constructs (283.5 N, SD 162.8, P =.039). Additionally, SS (1.9 mm, IQR 0.87) had a significantly lower maximum total graft displacement during the cyclic loading protocol compared with SB (3.8 mm, IQR 2.4, P =.007) and BB (7.4 mm, IQR 3.1, P Conclusion: These findings support the potential of the SB fixation technique as a viable alternative to SS and BB constructs. Clinically, the SB technique could reduce the incidence of loading-related graft complications seen in the first 3 months of BB Latarjet cases. The study is limited to time-specific results and does not account for bone union or osteolysis.</p