Defining prerequisites for optimising outcomes of shoulder arthrodesis in post-traumatic brachial plexus palsy

PURPOSE: Persistent pain, joint subluxation, instability, and limited shoulder mobility present significant reconstructive challenges in post-traumatic brachial plexus injury. This study aims to determine the essential prerequisites for attaining optimal functional results after shoulder arthrodesis in patients with post-traumatic brachial plexus palsy. METHODS: Between 2017 and 2023, ten patients underwent shoulder arthrodesis, five with upper plexus palsy (mean age 35 years) and five with global palsy (mean age 31 years). The preoperative assessment included an evaluation of the integrity of the periscapular muscles. Arthrodesis was performed using a 3.5-mm locking reconstruction plate, positioning the shoulder in 30° forward flexion, 30° abduction, and 30° internal rotation. Patients were followed for a mean of 30 months, and outcomes were assessed in terms of radiological union, range of motion in terms of abduction, protraction, and retraction, brachiothoracic grasp, pain using the Visual Analog Scale and patient satisfaction using the Disabilities of the Arm, Shoulder, and Hand. RESULTS: All patients achieved radiological union within an average of 8.5 months, with significant pain relief (mean VAS score: 1.1). Patients with global palsy demonstrated reduced mean forward flexion (38°) compared to those with upper palsy (68°). However, differences in abduction and external rotation were minimal. Functional gains were consistent across all patients, including improved brachiothoracic grasp, hand-to-mouth function, and stability. CONCLUSION: Shoulder arthrodesis remains a valuable salvage option for patients with multiple nerve avulsions or limited donor nerve availability. Optimal results with shoulder arthrodesis were observed in patients with intact or reanimated periscapular muscles. The procedure provides reliable pain relief and functional stability in post-traumatic brachial plexus palsy.