Related Experiment Video
Updated: Dec 31, 2025
Polytetrafluoroethylene PTFE as a Suture Material in Tendon Surgery
Published on: October 6, 2022
Variation of Extrinsic Tendons of the Thumb in Type IIIA Hypoplastic Thumbs
Yuki Bessho1, Takehiko Takagi1, Atsuhito Seki1
1Division of Orthopaedic Surgery, Department of Surgical Specialties, National Center for Child Health and Development, Tokyo, Japan.
Purpose:
The purpose of this study was to identify the variety of anatomical abnormalities of extrinsic tendons in type IIIA hypoplastic thumbs.
Methods:
We reviewed 79 thumbs in 67 patients. Opponensplasty, stabilizing of the thumb metacarpophalangeal joint, and widening of the first web space were performed in all patients. At the time of surgery, we made detailed observations of the anatomical abnormalities of the extrinsic tendons of the thumb.
Results:
Fifty thumbs (50 of 79; 63%) had an interconnection between the flexor pollicis longus (FPL) and the extensor pollicis longus (EPL) tendons. Twenty-six thumbs (26 of 79; 33%) had bifurcations (25 [32%] bifurcated from the FPL; 1 [1%] bifurcated from the EPL). There were 25 FPL abnormalities (4 [5%] complete absence; 8 [10%] proximal absence; 2 [3%] distal absence; 11 [14%] tendon hypoplasia) and 7 EPL abnormalities (2 [3%] proximal absence; 5 [6%] tendon hypoplasia).
Conclusions:
Interconnections between the FPL and the EPL tendons and a duplicated FPL were observed frequently.
Clinical Relevance:
The present study investigates the detailed anatomy of the type IIIA hypoplastic thumbs. The data might help improve the design of surgical procedures.
Related Concept Videos
01:17Muscles 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...
01:16Muscles 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...