Endoscopic carpal tunnel release and nerve conduction studies

Abstract

We investigated the outcome of endoscopic carpal tunnel release (ECTR) for patients with carpal tunnel syndrome (CTS) in comparison with the results of preoperative nerve conduction studies. The compound muscle action potential (CMAP) of the abductor pollicis brevis muscle (APB) and the second lumbrical muscle (L2) was recorded following median nerve stimulation at the wrist. A total of 38 hands in 35 patients were classified into four categories. Hands with a similarly prolonged distal motor latency for the APB and L2 were classified as type 1 (n=25), while those with a more prolonged distal motor latency for the APB than for the L2 (>0.7 ms) were classified as type 2 (n=10). Hands with a CMAP for the APB, but not L2, were classified as type 3 (n=1), and hands with no CMAP for either the APB or L2 were classified as type 4 (n=2). After ECTR, all of the type 1 and 2 hands were improved. Patients with type 3 and type 4 hands did not show satisfactory improvement, which may have been due to anatomical variation of the recurrent motor branch of the median nerve.Résumé Nous avons examiné la réaction à des opéra-tions de libération du canal carpien endoscopique (LCCE) chez des patients souffrant d'un syndrome du canal carpien (SCC), en utilisant les résultats d'une etude de conduction des nerfs (ECN) préopératoire. La ré-action des potentiels de l'action des muscles composés (PAMC) de l'abducteur pollicis brevis (APB) et du second muscle lombrical (L2) fut enregistrée suivant une stimulation du nerf médian au poignet. Un total de 38 mains de 35 patients fut divisé en quatre catégories. Les mains avec SCC présentant une latence motrice distale prolongée similaire dans APB et L2, furent classées en tant que type 1 (25 mains). Celles avec SCC présentant une latence motrice distale plus prolongée dans APB que dans le L2 (>0.7 ms), furent classées en tant que type 2 (10 mains), celles avec SCC dont les PAMC de APB seuls furent mis en lumiére, furent classées en tant type que 3 (1 main), et celles avec SCC dont les PAMC à la fois de APB et L2 ne furent pas mis en lumière, furent classées en tant que type 4 (2 mains). Après la LCCE, toutes les mains des types 1 et 2 furent bien améliorées. Patients de types SCC 3 et 4 n'ont pas pré-senté une amélioration satisfaisante, par suite probablement d'une variation anatomique d'une branche motrice récurrente. IntroductionIt has been reported that endoscopic carpal tunnel release (ECTR) gives mostly satisfactory results in the treatment of carpal tunnel syndrome (CTS). There are some unsatisfactory results, however. We classified CTS according to the degree of involvement of the recurrent motor branch of the median nerve, based on nerve conduction velocity (NCV) studies, and report the results and the indications for ECTR in patients with CTS. Patients and methodsWe studied 38 hands in 35 patients, with symptoms of carpal tunnel syndrome by ECTR. There were five men and 30 women with a mean age of 66 years (31-83 years). The mean follow-up period was 8 months (3-32 months).W...

Neurophysiological Recovery After Open Carpal Tunnel Decompression: Comparison of Simple Decompression and Decompression with Epineurotomy

“…Neurophysiological results similar to ours have already been reported in small studies comparing open carpal tunnel release with, or without, internal neurolysis (Holmgren and Rabow, 1987;Lowry and Follender, 1988), and similar results have also been described after endoscopic carpal tunnel release (Genba et al, 1993;Nakamura et al, 1999;Uchiyama et al, 2001;Ueno et al, 2001). The merits of the present study are in its design and statistical analysis.…”

Infrared neural stimulation of human spinal nerve rootsin vivo

“…The high spatial selectivity of INS will allow clinicians to stimulate subfascicular for peripheral nerve reconstruction, such as brachial nerve plexus or otolaryngology applications, where surgeons have a need to identify small groups of fibers to determine function and connectivity. 45,46 Possible functional applications of INS include incorporation of the stimulation modality in neural prosthesis used to restore function, block pain, or treat movement disorders. Functional ES has been used to provide control of the bladder, reanimate paralyzed limbs, control pain, and treat movement disorders.…”

Application of infrared light for in vivo neural stimulation

“…Optical stimulation is ideal for a number of procedures that routinely employ electrical stimulation in neurosurgery, such as intraoperative diagnostics. In peripheral nerve surgery, electrical stimulation is utilized to identify the connectivity and functionality of specific nerve roots to be avoided or resected, 40 although lack in spatial specificity places severe limitations on this technique. Neurostimulation of the spinal cord for pain relief has become another use for electrical stimulation treatment.…”