Quantifying the Impact of C7 Spinal Nerve Harvest on Spontaneous, Patient-Initiated Movement of the Donor Upper Extremity.

Abstract

Transfer of a healthy C7 spinal nerve is a tool for upper extremity reanimation in patients with severe brachial plexus injury (BPI). Its use remains controversial because of concern for neurologic injury to the donor arm. Using wearable motion-sensor technology, the authors aimed to quantify donor arm morbidity after C7 spinal nerve harvest in patients with pan-BPI, reporting both the time and magnitude of donor arm movement in a real-world setting compared with healthy controls. Seventeen patients who underwent contralateral C7 (CC7) transfer for traumatic pan-BPI at least 2 years prior were compared with 14 healthy controls. Each participant wore an accelerometer on both arms for 7 consecutive days. The vector time (VT) (or time of movement measured in hours per day) and the vector magnitude (VM) (or magnitude of arm movement measured as a single vector magnitude per second) were collected and compared between groups. The correlation between VT and VM and time from C7 spinal nerve harvest was also calculated. At a mean of 7.7 years after C7 spinal nerve harvest, there was no difference between donor and control arms for VT (5.76 ± 1.55 versus 5.45 ± 1.22 hours; P = 0.56) or VM (2,242,236 ± 753,853 versus 1,919,223 ± 579,723 activity counts; P = 0.20), regardless of donor arm dominance. The C7 harvest cohort used the injured arm 53% of the time and with 27% of the power of the donor arm. There was no significant difference in time or magnitude of arm movement between donor arms and the arms of healthy controls. Therapeutic, IV.