Tendon of abductor pollicis brevis - MRI thumb - Axial PD FS - e-Anatomy
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Tendon of abductor pollicis brevis

Tendo abductoris brevis pollicis

Definition

Muhammad A. Javaid

The tendon of abductor pollicis brevis muscle courses distally and inserts into the lateral aspect of the base of the proximal phalanx of the thumb, and also sends fibers to the radial side of the dorsal aponeurosis (extensor expansion) of the thumb.

Its action is as the primary abductor of the thumb at both the carpometacarpal and metacarpophalangeal joints, moving the thumb away from the palm (in a perpendicular plane) and playing an essential role in thumb opposition and precision grip.

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.

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