Triangular Fibrocartilage Complex Injury

Triangular Fibrocartilage Complex is a pad of connective tissue overlying distal ulna
1. Originates at ulnar aspect of the radius
2. Two layers
  1. Deep layer inserts on ulnar fovea at base of ulnar styloid (most important for stability)
  2. Superficial layer inserts on ulnar styloid process
3. Components
  1. TFCC Disc
  2. Radioulnar ligaments
  3. Ulnar collateral ligament
  4. Ulnocarpal ligaments
TFCC Roles
1. Anchors articular disc between ulna and proximal Carpal Bones of the wrist
2. Cushions weight-bearing forces while grasping
3. Helps to stabilize the distal radial-ulnar joint

Inflammatory conditions
Acute Traumatic Injury (most common)
1. Follows injury with hyperpronation and an axial load (e.g. Fall on an outstretched hand, e.g. Skiing)
2. Typically affects medial insertion of TFCC at radius
Chronic degenerative changes
1. Typically affects central TFCC
2. Repetitive axial loading on wrist ulnar aspect (e.g. back handsprings)
3. Repetitive twisting, pronation-supination (e.g. Swinging baseball bat)
4. Other occupational repetitive strain (e.g. carpentry, plumbing)

Tenderness regions
1. Palmar extensor carpi ulnaris (ulnar fovea sign, most common finding)
2. Ulnar complex triangle (tissue between ulnar and radius)
Range of motion
1. Decreased pronation-supination range of motion
Weakness
1. Weak grip strength
Provocative maneuvers
1. Provocative range of motion planes (with pain limiting range of motion)
  1. Pronation and supination (may also result in a painful click at end points)
  2. Radial and ulnar wrist deviation
  3. Ulnar pain on passive Forearm rotation
2. Shuck Test positive for dorsal radio-ulnar instability
  1. Excessive movement or pain at radial-ulnar joint
3. Ulnar stress test (TFCC grind test)
  1. Ulnar pain with passive maximal ulnar deviation
4. Screwdriver test
  1. Pain with full Forearm supination to pronation while axial loading the ulnocarpal joint
5. Radial-ulnar compression by squeezing
6. Ulnocarpal compression
  1. Maximal ulnar deviation at full pronation and full supination
  2. High sensitivity but low Specificity

Wrist XRay
1. Typically normal in TFCC ligament tear
2. Ulnar variance may be present where ulna appears longer than radius (PA View)
3. Ulnar styloid Fractures may be present
MRI Wrist (definitive study)
1. Preferred with intraarticular gadolinium for contrast (MR Arthrography)
  1. Test Sensitivity 100%
  2. Test Specificity 86%
2. Views that best demonstrate ulnar variance (increased ulna length >2.5 mm more than radial length)
  1. Posteroanterior view with arm abducted 90 degrees, Forearm in neutral position
  2. Pronated posteroanterior grip
3. References
  1. Lee (2013) Skeletal Radiol 42(9): 1277-85 [PubMed]

Conservative Therapy (injuries >2 weeks old)
1. Hand therapy
2. NSAIDs
3. Relative rest
Splint Immobilization for acute injuries or refractory chronic injuries
1. Cock-up Wrist Splint for 4-6 weeks
2. Kinesio Taping may be used as alternative for mild injuries, or step-down from Splinting
Corticosteroid Injection for acute inflammatory TFCC pain
1. See TFCC Steroid Injection
Surgical repair in refractory cases