II. Anatomy
-
Triangular Fibrocartilage Complex is a pad of connective tissue overlying distal ulna
- Originates at ulnar aspect of the radius
- Two layers
- Deep layer inserts on ulnar fovea at base of ulnar styloid (most important for stability)
- Superficial layer inserts on ulnar styloid process
- Components
- TFCC Disc
- Radioulnar ligaments
- Ulnar collateral ligament
- Ulnocarpal ligaments
-
TFCC Roles
- Anchors articular disc between ulna and proximal Carpal Bones of the wrist
- Cushions weight-bearing forces while grasping
- Helps to stabilize the distal radial-ulnar joint
III. Pathophysiology: Mechanisms of Injury
- Inflammatory conditions
- Acute Traumatic Injury (most common)
- Chronic degenerative changes
- Typically affects central TFCC
- Repetitive axial loading on wrist ulnar aspect (e.g. back handsprings)
- Repetitive twisting, pronation-supination (e.g. Swinging baseball bat)
- Other occupational repetitive strain (e.g. carpentry, plumbing)
IV. Symptoms
- Ulnar dorsal Wrist Pain
- Click may be perceived on Forearm rotation
V. Signs
- Tenderness regions
- Palmar extensor carpi ulnaris (ulnar fovea sign, most common finding)
- Ulnar complex triangle (tissue between ulnar and radius)
- Range of motion
- Decreased pronation-supination range of motion
- Weakness
- Weak grip strength
- Provocative maneuvers
- Provocative range of motion planes (with pain limiting range of motion)
- Pronation and supination (may also result in a painful click at end points)
- Radial and ulnar wrist deviation
- Ulnar pain on passive Forearm rotation
- Shuck Test positive for dorsal radio-ulnar instability
- Excessive movement or pain at radial-ulnar joint
- Ulnar stress test (TFCC grind test)
- Ulnar pain with passive maximal ulnar deviation
- Screwdriver test
- Pain with full Forearm supination to pronation while axial loading the ulnocarpal joint
- Radial-ulnar compression by squeezing
- Ulnocarpal compression
- Maximal ulnar deviation at full pronation and full supination
- High sensitivity but low Specificity
- Provocative range of motion planes (with pain limiting range of motion)
VI. Imaging
- Wrist XRay
- MRI Wrist (definitive study)
- Preferred with intraarticular gadolinium for contrast (MR Arthrography)
- Test Sensitivity 100%
- Test Specificity 86%
- Views that best demonstrate ulnar variance (increased ulna length >2.5 mm more than radial length)
- Posteroanterior view with arm abducted 90 degrees, Forearm in neutral position
- Pronated posteroanterior grip
- References
- Preferred with intraarticular gadolinium for contrast (MR Arthrography)
VII. Management
- Conservative Therapy (injuries >2 weeks old)
- Hand therapy
- NSAIDs
- Relative rest
- Splint Immobilization for acute injuries or refractory chronic injuries
- Cock-up Wrist Splint for 4-6 weeks
- Kinesio Taping may be used as alternative for mild injuries, or step-down from Splinting
- Corticosteroid Injection for acute inflammatory TFCC pain
- Surgical repair in refractory cases
VIII. References
- Titchner, Morris and Davenport (2021) Crit Dec Emerg Med 35(5): 17-23
- Moore (1997) AAFP Sports Medicine Conference, Lecture
- Morgan (1997) Am Fam Physician 55(3): 857-68 [PubMed]
- Pujalte (2024) Am Fam Physician 110(4): 402-10 [PubMed]