Transverse head of adductor pollicis
Caput transversum adductoris pollicis
- Related terms: Transverse head
Definition
The transverse head is one of the distinct parts of the adductor pollicis muscle.
Origin
This head arises specifically from the palmar surface of the shaft of the third metacarpal bone.
Course and Insertion
Its fibers run transversely across the palm, converging laterally with those of the oblique head. The transverse head contributes to the common insertion of the adductor pollicis, attaching primarily to the ulnar sesamoid bone and the ulnar side of the base of the proximal phalanx of the thumb. Some of its fibers extend to join the dorsal aponeurosis of the thumb.
References
Okwumabua E, Sinkler MA, Bordoni B. Anatomy, Shoulder and Upper Limb, Hand Muscles. [Updated 2023 Jul 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537229/
Loss J Li ZM. Biometry of thenar muscle origins on the flexor retinaculum. Clin Anat. 2020 Nov;33(8):1176-1180.