TFCC Injuries & Ulnar-Sided Wrist Pain
Overview
The triangular fibrocartilage complex (TFCC) is a disc-shaped cartilaginous structure on the ulnar side of the wrist that cushions and stabilises the distal radioulnar joint (DRUJ) and ulnocarpal joint. It is analogous to the knee meniscus in structure and function. TFCC tears are a leading cause of ulnar-sided wrist pain — a challenging and frequently underdiagnosed clinical problem. The TFCC can be injured acutely (traumatic tear — Palmer Class I) or undergo degenerative thinning with age (degenerative tear — Palmer Class II).
Anatomy & Function
The TFCC comprises the central articular disc, the dorsal and volar radioulnar ligaments (the primary stabilisers of the DRUJ), the ulnolunate and ulnotriquetral ligaments, the extensor carpi ulnaris (ECU) tendon sheath, and the meniscus homologue. It originates from the sigmoid notch of the radius and inserts onto the fovea at the base of the ulnar styloid. The avascular central portion has no healing potential; the peripheral vascular region can heal with appropriate treatment.
Causes & Symptoms
- Traumatic: Fall on the outstretched wrist, forceful forearm rotation, axial loading of the wrist, or distal radius fracture disrupting the TFCC attachment
- Degenerative: Age-related thinning — incidental TFCC tears on MRI are found in >50% of individuals over 60
- Ulnar-sided wrist pain: Localised to the ulnar aspect of the wrist, aggravated by gripping, forearm rotation (particularly pronation with load), and impact activities
- DRUJ instability: A sensation of the ulnar head ‘clicking’ or ‘subluxing’ with forearm rotation — suggests disruption of the radioulnar ligaments
- The ‘piano key sign’: Abnormal dorsal subluxation of the distal ulna that reduces with passive pressure, like depressing a piano key — indicates DRUJ instability
Diagnosis
- MRI arthrogram: Gold standard — gadolinium contrast permeates through the tear, highlighting the defect. Sensitivity and specificity >85% in experienced hands.
- Wrist arthroscopy: The definitive diagnostic and therapeutic tool. Allows direct visualisation of the TFCC, assessment of the size and location of the tear, and simultaneous treatment.
Treatment
- Non-surgical: Peripheral tears in vascular zones may heal with 6–8 weeks of immobilisation in a long-arm cast (limiting forearm rotation). Corticosteroid injection into the DRUJ for degenerative tears.
- Arthroscopic TFCC repair: Peripheral tears are repaired under arthroscopic visualisation using inside-out suture techniques or suture anchors at the foveal insertion. Central degenerative tears are debrided to a stable rim.
- DRUJ stabilisation: For significant DRUJ instability from ligament disruption — arthroscopic or open ligament reconstruction.
- Ulnar shortening osteotomy: For degenerative Class II tears associated with ulnar positive variance (the ulna is longer than the radius) — the ulna is shortened to unload the ulnocarpal joint, relieving pressure on the degenerate TFCC.
Patient FAQs –TFCC Injuries & Ulnar-Sided Wrist Pain
I've had ulnar-sided wrist pain for months and multiple tests have been normal — what should I do?
Ulnar-sided wrist pain is notoriously difficult to diagnose and is one of the most frequently missed conditions in hand surgery. Plain X-rays and even MRI can appear normal in the presence of significant TFCC pathology. If your symptoms persist, Dr. Senthilvelan may recommend an MRI arthrogram (with contrast injection) or, if this is also inconclusive, a diagnostic wrist arthroscopy — which allows direct visualisation of structures that imaging cannot adequately assess.
