AbstractBackground: Third common palmar digital nerve / third carpal digital nerve (TCDN) has been described as the most commonly injured digital nerve during carpal tunnel release (CTR). Anatomic variations of the origin and course of the TCDN from the median nerve may place this structure at risk. Anatomic landmarks may be useful to predict the location of the TCDN to minimize the risk for injury to this structure during CTR. Aim: TO study the anatomy, landmarks and variations of origin and course of TCDN from median nerve. Material and Methods: THE study comprised of 30 upper limbs from 15 cadavers. TCDN in them were dissected using classical incisions given in Cunninghams’ manual. Results: Type 1 TCDN origin was found in 33.33%, type 2 origins was found in 67% and type 3 origin was found in 10% cases. Mean distance of origin of TCDN was 5.9 mm distal to cardinal line and 23 mm proximal to cardinal line. As TCDN course distally, its trajectory compared with oblique vector denotes, in 60% cases TCDN runs along vector, in 36.67% cases nerve runs medial to oblique vector and in 3.33% cases nerve runs lateral to vector. Conclusion: Study of anatomy, landmarks and variations of origin and course of TCDN from median nerve may be helpful to predict location of TCDN to minimize risk of injury to TCDN during CTR.
Keywords: Third Carpal Digital Nerve; Superficial Palmar Arch; Carpal Tunnel.