TFCC Injuries
Anatomy
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TFCC separates the ulna from the carpus and separates the radiocarpal from the
distal radioulnar joint
thickness of TFCC is roughly 5 mm at ulnar side and 2 mm thick at radial side;
Variable thickness of TFC from 1 - 5mm depending on the station of the ulna
(TFCC is thicker in individuals who are ulnar minus.)
components
1. TFC proper (central avascular portion)
2. dorsal and volar radio-ulna ligaments
3. ulnocarpal ligament (ulnolunate and ulnotriquetral)
4. the meniscus homologue (lunocarpal)
5. the articular disc
6. sheath of ECU
Insertions
1. ulnar border of distal radius
2. inserts into the base of the ulnar styloid - deep part called the ligamentum
subcruetum attaches to the fovea
3. Distally, it inserts into the lunate via the ulnolunate (UL) ligament and the
triquetrum via the ulnotriquetral (UT) ligament
4. these ligaments are tight on supination
Blood supply
 dorsal and palmar branches of the anterior interosseous artery and dorsal
and palmar radiocarpal branches from the ulnar artery
 Marginal blood supply penetrates 10-40% from the TFCC margins
(decreases with age)
 central disk and radial attachment are avascular;
 Because the periphery of the TFCC has good blood supply, tears in this
region can be repaired. In contrast, tears in the central avascular area must
be debrided, as they have no potential for healing.
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Functions
1. Cushion for ulnar carpus – takes 20% of the axial load
2. Major stabiliser of the DRUJ
3. Stabiliser of the ulnar carpus
Aetiology
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Causative conditions for TFCCs include the following:
1. Falls onto pronated hyperextended wrist
2. Power drill injuries in which the drill binds and rotates the wrist instead of the
bit
3. Distraction force applied to the volar forearm or wrist
4. Distal radius fractures
Pathophysiology
 main stabilizer of distal radioulnar joint, in addition to contributing to
ulnocarpal stability
 during axial loading, the radius carries the majority of load (82%), and the ulna a
smaller load (18%);
 small changes in relative ulnar length can significantly alter load patterns across
the wrist - increasing the ulnar variance to a positive 2.5 mm increases the load
transmission across the TFCC to 42%;
 percentage of axial force transmitted through the ulna decreases by sequential
removal of the horizontal portion of the TFCC - with the TFCC excised, the radial
load increases to 94%;
 TFCC tears are associated with a positive ulnar variance. Ulnar variance increases
with pronation and grip. Ulnar variance decreases with supination.
 TFCC is an important pulley for the ECU tendon and disruption of the normal
ECU excursion may contribute to abnormal loading and force transmission
through the ulnar wrist and TFCC.
 DRUJ stability is maintained by
1. TFCC
2. interosseous membrane
3. pronator quadratus
4. shape of joint surfaces
Volar view of the distal radio-ulnar joint in full
supination showing stabilizing structures. 1--3 =
ulnocarpal ligaments, 4 = palmar radioulnar ligament, 5
= dorsal radioulnar ligament, ECU = extensor carpi
ulnaris and ECU sheath, PQ = pronator quadratus, IOM
= interosseous membrane, black arrow = coaptation of
ulnar head against sigmoid notch of radius
Clinical
 present with ulnar-sided wrist pain, frequently with clicking.
 no correlation between ulnar styloid fractures and TFCC injuries.
 TFCC compression test - ulnar deviation of the wrist with the forearm in neutral
produces ulnar wrist pain and occasional clicking
 DRUJ stress test – distract the distal radius against the ulnar
 Piano key sign - a prominent and ballottable distal ulna with full pronation of
the forearm
Ulnocarpal impaction syndrome
 Ulnar sided wrist pain with associated ulna positive variance
 Distal ulna impacts against TFCC and in particular proximal lunate resulting in
erosion
Investigations
Wrist xrays
 ulnar variance
o note ulnar variance becomes positive with pronation and power grip
 chondromalacia of the lunate or ulnar head
 degenerative joint disease of the DRUJ, LT or scapholunate (SL) instability,
 dorsiflexed intercalated segment instability (DISI), or volar flexed intercalated
segment instability (VISI).
Wrist arthrograms
MRI
 80% sensitivity and 70% specificity using a dedicated wrist coil.
Wrist arthroscopy
 Gold standards
 allows for assessment of the size of the tear, for determining whether an unstable
flap is present, and for detecting associated synovitis and chondral and
ligamentous lesions.
 Trampoline test – center of the TFC is balloted by probe – if probing fails to elicit
trampoline, a peripheral tear is suspected.
Classification (Palmer – J Hand Surg 1989)
Class 1: Traumatic
Class 1A - Central perforation
 Usually located near radial attachment
Class 1B - Ulnar avulsion with or without distal ulna styloid fracture at base
Class 1C - Distal avulsion (ulnocarpal ligaments – UT/UL)
 Often result in carpal instability – volar translocation of ulnar carpus
Class 1D - Radial avulsion with or without sigmoid notch fracture
Class 2: Degenerative (ulnocarpal abutment syndrome) stage
Class A - TFCC wear (earliest change is synovitis)
Class B - TFCC wear with lunate and/or ulnar chondromalacia
Class C - TFCC perforation with lunate and/or ulnar chondromalacia
Class D - TFCC perforation with lunate and/or ulnar chondromalacia and LT
ligament perforation
Class E - TFCC perforation with lunate and/or ulnar chondromalacia, LT ligament
perforation, and ulnocarpal arthritis
Treatment
Nonsurgical
 NSAIDs
 Immobilization in slight flexion and ulnar deviation in a short arm cast for 4-6
weeks, followed by removable wrist splints and physical therapy
Surgical
Traumatic
 Acute disruption will be associated with dorsal ulnar dislocation (forced
hyperpronation) or rarely volar dislocation (supination)
o Attempt closed reduction
o Otherwise open K wire (common with distal radial fractures and Galleazzi
fracture-dislocations)
 Type 1A:arthroscopic debridement
 Type 1B:open or arthroscopic reattachment
 Type 1C: arthroscopic debridement or open repair
 Type 1D:open or arthroscopic reattachment
Degenerative (Ulnocarpal impaction)
 For milder disease, arthroscopic debridement is useful
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General arthroscopic principles are as follows:
1. Debride to a stable smooth rim of tissue.
2. Maintain a 2-mm peripheral rim.
3. Excise less than two thirds of the central portion of the TFCC.
4. Maintain ligamentous integrity
As long as dorsal and palmar radioulnar ligaments are preserved,
debridement of the central portion of the horizontal disc does not
compromise stability of the DRUJ
For advanced DRUJ instability without arthritis
 Options
1. TFCC repair/debridement
2. TFCC reconstruction
TFCC reconstruction
 Indications: If the TFCC is not repairable or the repair is unsuccessful as
demonstrated by continued instability, pain, and decreased range of motion
 bony malunions and length discrepancies must be corrected before or at the time
of soft tissue reconstruction
 contraindicated if arthritis present
1. advancement of the pronator quadratus (Johnson)
o decrease dorsal instability of the distal ulna.
o pronator quadratus is advanced from its normal insertion point on the
distal ulna to a more lateral and posterior insertion
2. Bunnell-Boyes ulnocarpal reconstruction
o recreates the stabilizing force of the ulnocarpal ligaments
o Distally based half of FCU raised
o distal portion of the harvested tendon is stabilized by weaving it through
the volar capsule to relieve possible torque experienced by the
pisotriquetral joint.
o proximal portion of the harvested tendon is passed through a drill hole in
the ulna close to the styloid and sutured to itself.
o repair is completed with imbrication of the dorsal capsule
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Consider ulnar-shortening osteotomy for patients with
o ulnar positive variance
o patients in whom debridement fails
o patients who present with a delay in treatment of longer than 6 months.
Advantages of an ulnar-shortening osteotomy are as follows:
1. Extraarticular
2. Maintains the mechanical integrity of the DRUJ
3. Maintains the origins and insertions of the ligamentous tissue and capsule
forming the peripheral aspect of the TFCC; may result in tightening of the
ulnocarpal complex including the LT ligament with shortening
For advanced DRUJ instability with arthritis
1. Darrach procedure
a. Problems
i. instability of the remaining ulnar shaft
ii. impingement against radius during rotation and gripping
2. Sauve-Kapandji (Lowenstein) procedure
a. Arthrodesis of the DRUJ and resection of a more proximal portion of ulnar
to create a pseudarthrosis for forearm rotation
3. Wafer procedure
a. Resection of distal aspect of ulnar head open or arthroscopically (via a
central perforation) for ulnoimpaction syndrome.
b. 50% unloading of the ulnar side of the wrist after excision of the central
portion of the TFCC and resection of the radial two thirds of the width of
the ulnar head to a depth of subchondral bone