Flexor Carpi Radialis Tendon Insertion Onto the Trapezial Ridge: An Anatomic Description

PURPOSE: The flexor carpi radialis (FCR) tendon is often involved in surgical procedures of the hand and wrist. The FCR tendon may be mobilized from the trapezium during distal radius fracture fixation, for tendon transfer, and during carpometacarpal joint procedures. There is a paucity of literature describing the anatomy of the FCR insertion onto the trapezial ridge. We analyzed the insertional characteristics of the FCR onto the trapezium. METHODS: Forty-two fresh-frozen cadaveric wrists were dissected using the extended FCR approach through the FCR tendon sheath. The length of the fibrous portion of the FCR insertion onto the trapezial ridge was measured from proximal to distal using a digital caliper. RESULTS: FCR insertion onto the trapezium was present in all specimens. The mean length of the FCR insertion was 11.8 ± 4.14 mm. The character of the tissue quality varied across specimens. CONCLUSIONS: These results demonstrate the commonality of the FCR fibers that insert onto the trapezium. The length and tissue quality of this insertion varied across specimens. CLINICAL RELEVANCE: Understanding the complex anatomy of the hand and wrist facilitates surgical planning and intraoperative techniques. The FCR tendon insertion onto the trapezium is an important component of exposure for the volar approach to the distal radius and surgical management of thumb carpometacarpal joint arthritis.