Anatomic variations of the median nerve in the carpal tunnel: a brief review of the literature

Abstract

Carpal tunnel syndrome (CTS) is a common focal peripheral neuropathy. Increased pressure in the carpal tunnel results in median nerve compression and impaired nerve perfusion, leading to discomfort and paresthesia in the affected hand. Surgical division of the transverse carpal ligament is preferred in severe cases of CTS and should be considered when conservative measures fail. A through knowledge of the normal and variant anatomy of the median nerve in the wrist is fundamental in avoiding complications during carpal tunnel release. This paper aims to briefly review the anatomic variations of the median nerve in the carpal tunnel and its implications in carpal tunnel surgery. KeywOrds: Median nerve, Anatomic variation, Carpal tunnel, Transverse carpal ligament ÖZKarpal tünel sendromu (KTS) sık görülen bir periferik nöropatidir. Karpal tünel basıncının artması median sinirin sıkışmasına ve kanlanmasının bozulmasına yol açar. Ağır vakalarda ve konservatif tedavinin yeterli olmadığı durumlarda cerrahi olarak transvers karpal ligamanın kesilmesi tercih edilir. Karpal tünelin gevşetilmesi sırasında komplikasyonlardan kaçınmak için median sinirin bu bölgedeki ayrıntılı anatomisinin ve varyasyonlarının iyi bilinmesi gereklidir. Bu derleme median sinirin karpal tüneldeki olası anatomik varyasyonlarını ve bunun karpal tünel cerrahisine etkilerini kısaca gözden geçirmek amacıyla yazılmıştır.

A rare variant innervation of adductor pollicis muscle from median nerve in an adult cadaver in middle east: a case report

“…[17] Raised pressure in the carpal tunnel may result in median nerve compression and altered nerve perfusion may lead to discomfort and paraesthesia in the hand of affected side which may require surgical procedure for decompression. [18] Significant variation has been recognized in the nerve supply of the intrinsic muscles of the hand muscles which may have clinical implications. Knowledge of anatomical variations on the part of the surgical team is extremely important to avoid iatrogenic injuries and improve the prognosis of median nerve decompression and various graft surgeries.…”

Study of branching pattern of median nerve at carpal tunnel and its importance in surgical anatomy

“…Increased pressure in the carpal tunnel results in median nerve compression and impaired nerve perfusion, leading to discomfort and paraesthesia in the affected hand. 1 Anatomic variations of the median nerve are frequent and significant for wrist surgeries with short incisions and endoscopic procedures in treatment of carpal tunnel syndrome. These procedures demand through knowledge of anatomy and its variations of the structures in wrist.…”

The angular course of the median nerve in the distal forearm and its anatomical importance in preventing nerve injury in a modern era of carpal tunnel release

“…This is particularly important in light of the currently used endoscopic and open techniques that emphasize a minimally invasive approach. 3,11,25,33 While there are many reports on anatomical variations around the carpal tunnel, 12,23,26,41 there is little mention of the median nerve (MN) in the distal forearm as it approaches the wrist. Most figures depict the MN as taking a linear course that parallels the long axis of the forearm (LAF).…”