Mid-Term Outcome after Selective Neurotization of the Infraspinatus Muscle in Patients with Brachial Plexus Birth Injury

Abstract

Background: Active shoulder external rotation in adduction can be restored by selective neurotization of the infraspinatus muscle with the spinal accessory nerve in select patients with brachial plexus birth injury. Does the improved shoulder external rotation stand the test of time? Methods: Fourteen consecutive brachial plexus birth injury patients with active shoulder external rotation in adduction of ≤ 0 degrees and active shoulder elevation ≥ 90 degrees underwent selective neurotization of the infraspinatus muscle at mean 2 years of age between 2012 and 2016. All 14 patients had congruent shoulders joints with passive external rotation in adduction of 30 degrees. Pre-and postoperative electromyography was done to seven patients. Shoulder function and the subjective outcome was assessed after a mean follow-up of 3.8 years. Results: Shoulder external rotation in adduction improved by a mean 57 degrees in the 12 children who did not develop shoulder internal rotation contracture. Shoulder external rotation in abduction and shoulder abduction increased in all 14 patients. Reinnervation of the supraspinatus muscle was evident in all seven children who underwent postoperative EMG. Thirteen patients’ parents were satisfied with the outcome. Conclusions: Functionally significant shoulder external rotation can be restored and maintained by reinnervation of the infraspinatus muscle in brachial plexus birth injury patients with congruent shoulder joints, if internal rotation contracture does not develop.

A protocol-based treatment plan to improve shoulder function in children with brachial plexus birth injury: a comparative study

“…A congruent shoulder with normal ROM is a prerequisite for subsequent tendon or nerve transfers, which underlines the importance of early diagnosis and treatment of posterior shoulder dislocation. Shoulder ER can be improved by various tendon or nerve transfers (Bahm et al., 2005; Elhassan, 2014; Grahn et al., 2020; Grossman et al., 2004; Soldado, 2020; Waters et al., 2008) and several authors advocate surgery to restore missing external rotation before 3 years of age in order to maintain shoulder congruence and prevent development of glenohumeral deformity (Hui and Torode, 2003; Pearl et al., 2003; Van Heest et al., 2010; Vuillermin et al., 2020; Waters and Bae, 2008). One of the reasons for our decreased rate of relocation is an improved understanding and a more active approach in keeping the shoulder in place, aimed at restoring active function before 3 years of age.…”

Recent Advances in the Treatment of Brachial Plexus Birth Injury

“…More recently, selective transfer of the SAN to the infraspinatus branch of the SSN has been described in patients with congruent glenohumeral joints with encouraging results: a preliminary series showed that 86% of patients had active external rotation greater than 20 degrees beyond the sagittal plane. 65…”

“…the infraspinatus branch of the SSN has been described in patients with congruent glenohumeral joints with encouraging results: a preliminary series showed that 86% of patients had active external rotation greater than 20 degrees beyond the sagittal plane. 65 To date, no studies have convincingly demonstrated improved active external rotation when comparing the outcomes of SAN-to-SSN transfer versus nerve grafting; in fact, earlier studies with at least 3 years of follow-up demonstrated that both techniques resulted in suboptimal improvement in external rotation [59][60][61] (Table 3). More recent data continue to show poor outcomes for external rotation with both nerve grafting and nerve transfer, with mean postoperative AMS scores for both groups below the threshold of functionally meaningful active motion (AMS ≥ 6).…”

Transferência do nervo subescapular inferior para o ramo motor do músculo redondo menor: estudo anatômico

“…Grahn et al 46 , em 2020, publicam um estudo com 14 casos de transferência do nervo acessório (XI) para o ramo motor do músculo infraespinal.…”

“…Devido a isso, alguns artigos recentes propuseram transferência nervosa seletiva para atingir rotação externa ativa do ombro[45][46][47] . Os três estudos encontrados na literatura têm como alvo crianças com mais de 18 meses que tiveram boa recuperação nervosa espontânea, com exceção do ganho ativo de rotação externa do ombro.…”