Resolving Co-Contraction of the Elbow in Patient with Sequelae of Obstetric Brachial Plexus Palsy: A Cohort Study

Abstract

Background: Obstetric brachial plexus palsy can cause deformities of the upper extremity in up to 92% of patients. Elbow reconstruction is difficult because co-contraction of the elbow flexor (EF) and elbow extensor (EE) muscles makes the traditional treatment strategy ineffective. The authors propose a novel strategy to minimize the effect of co-contraction, comprising transfer of an EF to the triceps and a staged gracilis muscle transplantation [functioning free muscle transplantation (FFMT)] to augment EF. The authors hypothesize this will lead to improved elbow flexion and extension, as well as decreased elbow flexion contracture. Methods: A single-center retrospective review of patients who received a gracilis FFMT for EF after EF-to-EE transfer was performed. EF/EE strength and range of motion data were collected from the last clinical visit. Patients were excluded if they had fewer than 1.5 years of follow-up. A control group with sequelae of obstetric brachial plexus palsy and nonsurgical treatment was used for comparison. Results: Twenty-one patients were included. Average age at muscle transfer was 7.6 ± 5.5 years (range, 3 to 22 years) and at gracilis FFMT was 10.4 ± 6.0 years (range, 5 to 26 years). Average follow-up was 7.3 ± 6.5 years (range, 1.5 to 14.8 years). After EF-to-EE transfer, EE strength increased significantly from Medical Research Council grade 2.2 ± 0.4 to 3.4 ± 0.5 (P < 0.0001) and EF decreased from 3.2 ± 1.1 to 1.1 ± 1.1 (P < 0.0001) and recovered to grade 3.3 ± 0.7 after gracilis FFMT. EF contracture was significantly lower compared with that in the nonsurgical cohort (P = 0.029). Conclusion: Patients who undergo EF-to-EE transfer followed by gracilis FFMT have equivalent EF strength with significantly improved EE and improved elbow flexion contracture. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.