Flexor carpi radialis brevis: case report of a symptomatic tear

Abstract

Anatomical variants of muscle are commonly encountered by surgeons and radiologists. The flexor carpi radialis brevis (FCRB) is an anomalous muscle in the distal forearm with an estimated prevalence of 2-8%. In the literature, there are a few case reports of symptomatic FCRB tenosynovitis without a concomitant tear, and treatment methods described include both conservative and surgical management. We present a case of one patient with radial sided wrist pain and a partial FCRB tear, which to our knowledge is the first case report of a symptomatic FCRB tear. We also review existing literature regarding FCRB anatomy, particularly related to intra-operative dissection and exposure. Identification of an anomalous FCRB on imaging may serve to guide clinicians in their differential diagnosis of radial-sided wrist pain, in which FCRB pathological conditions ought to be included.

Flexor carpi radialis brevis identified during volar approach for distal radial fracture fixation: a review of the literature and case report

“…2 The presence of FRCB is, however, asymptomatic in the overwhelming majority. 1 The patient in this report did not report any wrist-related symptoms prior to traumatic injury.…”

“…The volar approach to DRF has become increasingly favored among orthopaedic and plastic surgeons because of the introduction of the volar locking plate system. 1 It utilizes the intermuscular plane between flexor carpi radialis and brachioradialis. If FCRB is encountered during the approach, the surgeon must be prepared to dissect and retract the FCRB in order to facilitate exposure, thus deviating from the typical intraoperative course.…”

“…W ith the advent of the volar locking plate system, the volar approach for the fixation of distal radial fractures (DRFs) is becoming increasingly favored. 1 Sound anatomical reduction requires adequate exposure of the forearm musculature. Consequently, there have been numerous case reports of surgeons encountering the anomalous flexor carpi radialis brevis (FCRB) muscle intraoperatively.…”

“…With the advent of the volar locking plate system, the volar approach for the fixation of distal radial fractures (DRFs) is becoming increasingly favored 1. Sound anatomical reduction requires adequate exposure of the forearm musculature.…”

The Flexor Carpi Radialis Brevis: A Description of an Anomalous Wrist Flexor and Surgical Exposure Technique

“…In addition, it has been implicated as a cause of radial sided wrist pain because of symptomatic tears, intersection with the FCR, and carpal tunnel syndrome. [4][5][6] Volar wrist pain postoperatively (thought to be a result of tenosynovitis) has also been reported. 7 Knowledge of pertinent anatomy has implications for surgical exposure and for the protection of its innervation and vascular supply.…”