DRUJ involves numerous structures where the stability of 20% is given by distal radius and 80% by soft tissue
Anatomy
Diarthrodial trochoid Synovial Joint
Bony radio-ulnar articulation: Sigmoid notch (concave)
The shape of the sigmoid notch is
- Flat face ( most suseptical to injury)
- Ski shape
- C shape
- S shape
The lower end of ulna (semi-cylindrical convex)
Soft tissue stabilizers
- Ulnoligamentous complex (Triangular fibrocartilagenous complex TFCC: transmit 20 % of axial load)
- Triangular fibrocartilage (articular disc)
- Meniscal homologue
- Ulnocarpal (Ulnolunate, lunotriquetral ligaments)
- Dorsal/ Volar radioulnar ligament (Primary stabilizers)
- Ulnar collateral ligaments
Extensor carpi ulnaris subsheath reinforced medially by linea jugata
Clinical Features
Ulnar side wrist pain
Tenderness over ulnar aspect of wrist
Clicking sound, obvious instability and weakness on lifting weakness
The periphery of TFCC is well vascularized whereas the radial central portion is avascular
TFCC is composed of superficial and deep limbs
Clinical Tests
Focal tenderness just distal to ulnar styloid
The impingement sign
Supinating/ Pronating ulnar deviated wrist with elbow resting at 90 degrees on the table will have pain is a positive test
Ulna fovea sign
Detecting foveal disruption and UT ligament injuries
Pressing area between FCU tendon and Ulnar styloid between pisiform and volar margin of ulna
Piano Key test
Ulnar head is depressed volarly with examiner’s thumb and release: Suggest instability
Table-top test
Asking the patient to press both hands on a flat table with the forearm in pronation
The affected ulna is more prominent
Grind test
Compressing distal ulna and radius with examiner hand and pronating a grinding motion: Elicit pain
See also: Hand and Wrist examination
Investigation of DRUJ/TFCC
Xray shows ulnar variance comparable to the normal side
Arthroscopy
Arthroscopy is gold standard for evaluation of TFCC injuries
Arthroscopic trampoline test
Performed to assess TFCC resiliency by balloting a small portion with probe
Arthroscopic Hook test
Can be used to demonstrate peripheral detachment of TFCC
Arthroscopic suction test
Laxity of the TFCC when periphery scarred in or foveal attachment when the DRUJ is peripherally detachable
Classification
Injuries of DRUJ and TFCC: A Working classification
A. Acute TFCC Injuries
- Acute dislocation of DRUJ
- DRUJ associated with fractures, fracture-dislocation
B. Chronic DRUJ Injuries
- Chronic TFCC injures
- Ulnar impaction syndrome
C. DRUJ Arthritis
TFCC Injuries: Palmar classification
Melone described TFCC Injury
Stages | Features |
---|---|
Stage 1 | Detachment of TFC from ulnar styloid |
Stage 2 | ECU sub-sheath injury |
Stage 3 | Ulno-carpal ligament disruption |
Stage 4 | Lunotriquetral ligament injury |
Stage 5 | Mid-carpal ligament injury |
Treatment
Non-operative
Splinting or Above elbow cast
Modification of activities
Occupational therapy
NSAIDS
Steroid Injection may be tried, which fails to improve with conservative care requires surgical treatment
Surgical Treatment
Management of TFCC as per Palmer classification
Type 1A: Arthroscopic debridement ( avascular: not able to heal)
Type 1B: Peripheral ( Increase healing potential so arthroscopic/open repair)
Type 1C/ 1D: Repair
Type 2:
Goal of surgery is the reduction of radio-carpal loading by the following methods:
- Ulnar Shortening Osteotomy
- Darrach procedure (resection of the distal ulna)
- Sauve-Kapanji procedure (DRUJ arthrodesis and surgical pseudoarthrosis of distal ulna)
- Hemiresection and interposition arthroplasty
- DRUJ Implant arthroplasty