Surgical Release of Ulnar and Median Nerves in CMT1A: Prevention and Treatment of a Second Hit (P14-8.013)

Abstract

<h3>Objective:</h3> To evaluate outcomes of carpal tunnel (CT, CTS), cubital tunnel (CuT, CuTS), and Guyon’s Canal (GC, GCS) release in patients with Charcot-Marie-Tooth disease type 1A (CMT1A). <h3>Background:</h3> Peripheral nerves in patients with CMT1A are diffusely enlarged and areas of potential compression at the CT, CuT, and GC can be released to reduce the risk of a “second hit” (nerve injury due to compression) in the setting of their genetic, progressive neuropathy, however there is little data on the efficacy and timing of surgical nerve decompression. <h3>Design/Methods:</h3> Genetically diagnosed and suspected CMT1A patients that reported hand symptoms seen in clinic in 2021–2022 with electrophysiologic data who were evaluated by neurosurgery for surgical decompression for CTS, CuTS, and GCS were reviewed. <h3>Results:</h3> All patients had severe slowing of motor nerve conduction velocities and absent sensory responses on NCS consistent with CMT1A. Electrographic CTS occurred bilaterally in 83%(5/6). Electrographic bilateral GCS and unilateral CuTS were observed in 33%(2/6) of patients. Three patients with sonographic data all demonstrated diffuse enlargement of the ulnar and median nerves at the forearm (mean cross-sectional area, CSA=20 mm2 and 26 mm2). Focal narrowing occurred at the CT in two patients (mean CSA=11.2 mm2 vs 37 mm2 at the forearm). One patient underwent unilateral and one patient underwent bilateral decompression at the CT, CuT, and GC with a follow-up time of 8 months and 2 months. Both patients endorsed significant improvement of gross grip strength in at least one hand and resolution of median sensory abnormalities in territories of released nerves. <h3>Conclusions:</h3> Although altered due to the nature of CMT1A, electrophysiologic and sonographic data provided focal findings in our patients with hand symptoms. Patients who underwent surgical decompression had symptomatic benefits. These releases can reduce the risk of a “second hit” of neurologic injury due to compression. <b>Disclosure:</b> Dr. McKeen has nothing to disclose. Dr. Katyal has nothing to disclose. Dr. Sakamuri has received personal compensation in the range of $0-$499 for serving as a Conference Faculty with AANEM. Dr. Wilson has nothing to disclose. Dr. Greene has received personal compensation in the range of $500-$4,999 for serving as a Advisory Board Member with Dysimmune Diseases Foundation .