Hisao Kamiya1, Michio Kimura2, Satoshi Hoshino3, Masahito Kobayashi4, Masahiro Sonoo1. 1. Department of Neurology, Teikyo University School of Medicine, Tokyo, Japan. 2. Department of Orthopaedic Surgery, Teikyo University School of Medicine, Tokyo, Japan. 3. Central Laboratory, Teikyo University School of Medicine, Tokyo, Japan. 4. Faculty of Economics, Yokohama National University, Yokohama, Japan.
Abstract
INTRODUCTION: Opponensplasty is a surgical option for patients with severe carpal tunnel syndrome (CTS). We investigated prognostic factors of patients who lack a preoperative compound muscle action potential (CMAP) of the abductor pollicis brevis (APB) muscle to determine the necessity for single-stage opponensplasty. METHODS: We retrospectively enrolled 22 hands of 22 CTS patients. Prognostic factors considered were age, diabetes mellitus, the median sensory nerve action potential, distal motor latency of the second lumbrical (2L) CMAP (2L-DML), and its amplitude (2L-Amp). Postoperative APB-CMAP amplitude (post APB-Amp) at 12 months was used as the outcome measure. RESULTS: Only 2L-DML showed a significant correlation with post APB-Amp (r = -0.56). The contribution of 2L-Amp was not significant, although 3 hands with absent 2L-CMAP had a poor electrophysiological recovery. CONCLUSIONS: Prolonged 2L-DML and absent 2L-CMAP seem to be poor prognostic factors. Concurrent opponensplasty may not be necessary in patients with 2L-DML of 8 ms or less. Muscle Nerve 54: 427-431, 2016.
INTRODUCTION: Opponensplasty is a surgical option for patients with severe carpal tunnel syndrome (CTS). We investigated prognostic factors of patients who lack a preoperative compound muscle action potential (CMAP) of the abductor pollicis brevis (APB) muscle to determine the necessity for single-stage opponensplasty. METHODS: We retrospectively enrolled 22 hands of 22 CTS patients. Prognostic factors considered were age, diabetes mellitus, the median sensory nerve action potential, distal motor latency of the second lumbrical (2L) CMAP (2L-DML), and its amplitude (2L-Amp). Postoperative APB-CMAP amplitude (post APB-Amp) at 12 months was used as the outcome measure. RESULTS: Only 2L-DML showed a significant correlation with post APB-Amp (r = -0.56). The contribution of 2L-Amp was not significant, although 3 hands with absent 2L-CMAP had a poor electrophysiological recovery. CONCLUSIONS: Prolonged 2L-DML and absent 2L-CMAP seem to be poor prognostic factors. Concurrent opponensplasty may not be necessary in patients with 2L-DML of 8 ms or less. Muscle Nerve 54: 427-431, 2016.
Authors: Carlos Henrique Fernandes; João Baptista Gomes Dos Santos; Francisco Schwartz-Fernandes; A Lee Ostermann; Flávio Faloppa Journal: Rev Bras Ortop (Sao Paulo) Date: 2020-09-22