* Study Overview This single-arm prospective clinical trial evaluates the efficacy of gracilis free functional muscle transfer (FFMT) for restoring elbow flexion in patients with late-presenting brachial plexus injuries (≥12 months post-injury) or failed prior reconstructive surgery. The gracilis muscle is the preferred donor due to its reliable vascular pedicle, adequate excursion, long motor nerve, and minimal donor-site morbidity .
* Primary Objective To assess postoperative elbow flexion strength using the British Medical Research Council (BMRC) grading system following gracilis FFMT neurotized by intercostal nerves (ICN) or spinal accessory nerve (SAN).
* Secondary Objectives
* Evaluate active range of motion (AROM)
* Measure time to first detectable muscle contraction and time to maximum power
* Assess functional improvement via DASH scores
* Compare outcomes between ICN and SAN neurotization groups
* Compare outcomes between pediatric and adult patients
* Document complications, particularly elbow flexion contracture
* Key Inclusion Criteria
* Age 4-50 years
* Elbow flexion loss or severe weakness for \>12 months following brachial plexus injury (obstetric or traumatic)
* Weak ipsilateral latissimus dorsi and pectoralis major (\<M3), unsuitable for local muscle transfer
* Key Exclusion Criteria
* Age \<4 years (microvascular anastomosis feasibility concerns)
* Age \>50 years (diminished regenerative capacity)
* Presentation within 12 months of injury
* Reconstructable by local muscle or nerve transfer
* Elbow joint stiffness or contracture
* Uncontrolled comorbidities or inability to comply with rehabilitation
* Intervention
Gracilis FFMT harvested from the contralateral thigh with:
* \*\*Neurotization:\*\* ICNs (50%) or SAN (50%)
* \*\*Vascular anastomosis:\*\* Thoracoacromial artery (77%), thoracodorsal artery (13.6%), or subscapular artery (9.2%)
* \*\*Muscle tensioning:\*\* Elbow flexed 90-110° during inset
* Primary Outcome Measure Postoperative elbow flexion power (BMRC grade) at 24-month follow-up
* Secondary Outcome Measures
* Active range of motion (goniometry)
* Time to first clinical contraction
* Time to maximum power achievement
* DASH score
* Complication rate (flap loss, flexion contracture, scarring)
* Sample Size 22 patients (17 male, 5 female; mean age 13.4±8.7 years)
* Statistical Considerations
* Paired t-test for continuous outcomes
* Wilcoxon signed-rank test for non-parametric data
* Fisher's exact test for categorical comparisons
* Significance threshold: p\<0.05
* Expected Outcomes Based on existing literature, 68-76% of patients achieve functionally useful elbow flexion (≥M3) following gracilis FFMT, with significant improvements in AROM and DASH scores . ICN neurotization may offer faster recovery to maximum power (approximately 9 months vs. 14 months for SAN) without compromising final strength .
* Trial Registration:\*\* Not reported (retrospective/prospective case series design)