Magnetic Resonance Neurography Within a Multimodal Framework for Predicting C5 Root Graftability in Traumatic Brachial Plexus Injury.

Abstract

Background: Accurate preoperative assessment of C5 nerve root graftability is crucial for surgical planning in brachial plexus injuries. This study evaluates the diagnostic accuracy of magnetic resonance neurography (MRN) compared with clinical examination and electrodiagnostic studies in predicting C5 graftability.

Methods: This retrospective cohort study included 402 adult traumatic brachial plexus injuries patients undergoing nerve reconstruction at a single tertiary center between September 2008 and November 2024. Patients were categorized into panplexus (C5-T1, n = 166) and non-panplexus (n = 236) injuries. Diagnostic modalities included physical examination (deafferentation pain, Tinel's sign, rhomboid, and levator scapulae muscle power [MP]), electromyography of C5 paraspinal and rhomboid muscles, and high-resolution MRN with avulsion severity scoring. Intraoperative surgical inspection served as the reference standard. Multivariate logistic regression and receiver operating characteristic curve analysis evaluated diagnostic performance.

Results: Intraoperative exploration revealed graftable C5 roots in 195 patients (48.5%). MRN demonstrated the highest predictive value (odds ratio 9.171, p < 0.001). Optimal diagnostic models varied by injury pattern: Panplexus injuries showed optimal prediction with MRN plus Tinel's sign (area under the receiver operating characteristic curve 0.828), while non-panplexus injuries required MRN, Tinel's sign, and levator scapulae MP (area under the receiver operating characteristic curve 0.766). Electromyography showed limited diagnostic value.

Conclusions: MRN is a valuable tool for assessing C5 nerve root graftability, demonstrating the highest predictive performance among evaluated modalities. When combined with clinical examination, it supports structured preoperative decision making in brachial plexus reconstruction.

Level of evidence: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.