Skeletal Radiology

, Volume 48, Issue 3, pp 457–460 | Cite as

Flexor carpi radialis brevis: a rare accessory muscle presenting as an intersection syndrome of the wrist

  • Patcharee HongsmatipEmail author
  • Edward Smitaman
  • Gonzalo Delgado
  • Donald L. Resnick
Case Report


The flexor carpi radialis brevis (FCRB) is a rare accessory muscle of the forearm and wrist. It is typically asymptomatic, but has been discovered either incidentally during cadaveric studies or at the time of surgery in patients with distal forearm injury. Rarely, the FCRB muscle is associated with pain. We report a patient with wrist pain related to intersection between the tendon of the FCRB muscle and the tendon of the flexor carpi radialis (FCR) muscle, with an associated longitudinal split tear of the FCR tendon, documented by magnetic resonance imaging (MRI). To our knowledge, this is only the second report in the English literature of this intersection syndrome.


Flexor carpi radialis brevis (FCRB) Accessory muscle and tendon Tendon intersection syndrome 


Compliance with ethical standards



Conflict of interest


Grant support



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Copyright information

© ISS 2018

Authors and Affiliations

  • Patcharee Hongsmatip
    • 1
    • 2
    Email author
  • Edward Smitaman
    • 2
  • Gonzalo Delgado
    • 3
  • Donald L. Resnick
    • 2
  1. 1.Queen Savang Vadhana Memorial HospitalChonburiThailand
  2. 2.Department of RadiologyUniversity of California San DiegoSan DiegoUSA
  3. 3.Clinica MEDSSantiagoChile

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