Flexor Carpi Ulnaris (FCU) Tenderness

Description

• Flexor carpi ulnaris (FCU) tenderness occurs approximately 3 cm proximal to the FCU tendon’s insertion on the pisiform.¹
• FCU tendinopathy is similar to pathologies of the pisotriquetral (PT) joint.¹

Pathophysiology

• FCU tenderness may be caused by a flexor tendon injury, a triangular fibrocartilage complex (TFCC) tear, PT arthritis or posttraumatic arthritis. Tendon injuries often result from excessive mechanical overload.¹
• FCU tenderness may also be caused by acute calcific tendinitis, at the insertion of the FCU tendon at the pisiform. Acute calcific tendinitis is often misdiagnosed as an infection.²
• In rare cases, ulnar instability of the carpus may lead to FCU tenderness.

Instructions

1. Record the patient’s history, including any sports-related injuries. Ask the patient to rate how much pain s/he usually experiences in the affected wrist on a scale from 1 to 10.
2. Palpate the FCU tendon along its course to observe any focal tenderness.³
3. Check for crepitus, swelling and/or pain of the FCU.
4. Examine the contralateral wrist for comparison.

Variations

• Another symptom to consider is a clunking sensation of the ulnar wrist on palpation. This may indicate ulnar instability of the carpus.⁴

Related Signs and Tests

• PT tenderness
• TFCC tenderness
• Neurovascular exam
• Radiography
• Arthroscopy⁴

Diagnostic Performance Characteristics

• After examining the wrist, radiography and arthroscopy may be useful to improve reliability. Radiography can effectively diagnose acute calcific tendinitis.²
• Do not use other patients’ reactions as a comparison, because other patients may have different perceptions of similar tenderness and/or pain.

• A positive result occurs when there is increased tenderness in the FCU with pressure.

• A negative result occurs when pressure does not cause increased tenderness in the FCU. 

• In treating FCU injuries, if non-operative options do not succeed, FCU tendon debridement may relieve pain.¹

1. Budoff JE, Kraushaar BS, Ayala G. Flexor Carpi Ulnaris Tendinopathy. J Hand Surg Am 2005;30A:125-9. PMID: 15680567
2. Torbati SS, Bral D, Geiderman JM. Acute calcific tendinitis of the wrist. J Emerg Med 2013;44(2):352-4. PMID: 23116933
3. Culp R, Jacoby S. Musculoskeletal Examination of the Elbow, Wrist and Hand: Making the Complex Simple. New Jersey: SLACK Incorporated, 2012.
4. Pillukat T, Van Schoonhoven J, Lanz U. Ulnar instability of the carpus. (Article in German) Orthopade. 2004;33(6):676-84. PMID: 15127197