Optimization of Muscle Selection for Needle Electromyography in Isolated C6 Root Lesion: A Prospective Chart Review Study.

ABSTRACT

OBJECTIVES: The aim of the study is to evaluate muscles with more prominent needle electromyographic findings to optimize needle electromyography screening of isolated C6 radiculopathy in patients with C6 root lesions. DESIGN: This prospective clinical study was performed on 39 patients with isolated and unilateral cervical radiculopathy selected from all referrals of 1733 patients to the electrodiagnosis unit of the physical medicine and rehabilitation department of a tertiary medical center (from April 2021 to December 2021). The presence of fibrillation potentials, positive sharp waves, and/or neurogenic motor action potentials that occurred in isolation or combination with selected muscles was considered an abnormal finding. RESULTS: Of 1733 referrals, 39 patients (18 males [46.1%] and 21 females [53.8%]), with a mean age of 49.7 ± 9.6 yrs, were found eligible. According to needle electromyography findings, the most involved muscles in C6 root lesion were pronator teres (100%), followed by extensor carpi radialis longus (94.8%), flexor carpi radialis (89.7%), brachioradialis (82%), infraspinatus (82%), supraspinatus (79.4%), deltoid (74.3%), biceps brachii (64.1%), extensor digitorum communis (33.3%), and triceps brachii (15.3%) muscles. CONCLUSIONS: The pronator teres is the most involved muscle of patients diagnosed with C6 radiculopathy. It might be considered the key muscle for screening and accurate diagnosis of C6 root involvement.