Related Experiment Video
Updated: Jan 2, 2026

Author Spotlight: Enhancing Remote Rehabilitation with Virtual Reality and Electromyography
Published on: January 12, 2024
Anatomical variations of the abductor pollicis longus: a pilot study
P Karauda1, Ł Olewnik2, M Podgórski3
1Uniwersytet Medyczny w Łodzi, Kościuszki 4, 90-419 Łódź, Poland. piotrkaraudamail@gmail.com.
Background:
The abductor pollicis longus (APL) originates from the lateral part of the dorsal surface of the body of the ulna below the insertion of the anconeus muscle, from the interosseous membrane, and from the middle third of the dorsal surface of the body of the radius. However, the number of its accessory bands and their insertion vary considerably.
Materials And Methods:
Fifty upper limbs (2 paired, 31 male, 19 female) were obtained from adult Caucasian cadavers, and fixed in 10% formalin solution before examination.
Results:
The APL muscle was present in all specimens. The muscles were divided into three main categories, with type II and III being dived into subtypes. Type I was characterised by a single distal attachment, with the tendon inserting to the base of the I metacarpal bone. Type II was characterised by a bifurcated distal attachment, with the main tendon inserting to the base of the first metacarpal bone; this type was divided into three subtypes (a-c). Type III was characterised by the main tendons inserting to the base of the first metacarpal bone, while the accessory band was characterised by mergers (fusion) with other tendons. This type was divided into two subtypes (a, b).
Conclusions:
The abductor pollicis longus is characterised by high morphological variability.
More Related Videos
10:36Vascularized Composite Hand Allograft Procurement and Preparation for Distal and Proximal Forearm Allotransplantation: A Stepwise Approach
Published on: May 23, 2025
08:12Author Spotlight: Isolation of Long Muscle Fibers from Mouse Hindlimb Muscles for Studying Excitation-Contraction Coupling Across Fiber Types
Published on: December 1, 2023
Related Concept Videos
Muscles of the Forearm that Move the Hand and Fingers
Anterior Compartment
The anterior compartment muscles originate from the humerus. They primarily function as flexors and are also known as flexor muscles. They typically insert on the carpals, metacarpals, and phalanges. The superficial layer includes the flexor carpi...
Muscles that Move the Forearm
Forearm Flexors
The biceps brachii, brachialis, and brachioradialis are forearm flexors. The biceps brachii is made up of two heads. Its long head originates at the supraglenoid tubercle of the scapula, whereas that of the short head is...
Bones of the Upper Limb: Ulna
Bones of the Upper Limb: Radius
The radius has a nail-shaped head, and a...
Muscles of the Leg that Move the Foot and Toes
Anterior Compartment
The anterior compartment includes muscles that contribute to the dorsiflexion of the foot. This compartment houses the tibialis anterior, extensor hallucis longus, and extensor digitorum longus muscles....
Spinal Nerves: Plexus I
The Cervical Plexus
The cervical plexus, formed by the anterior rami of the first four...