Description
The triangular fibrocartilage complex [TFCC] is a soft tissue structure covering the distal ulna at the wrist,
which serves to help stabilize the wrist and transmit load across the wrist joint. Because of its anatomic
complexity and the forces that it experiences, the TFCC is at risk for both direct injury and degenerative
damage. As such, TFCC pathology is a common cause of ulnar sided wrist pain.
Structure and Function
The triangular fibrocartilage complex (TFCC) is located at the ulnar wrist, articulating with the head of the
ulna proximally and the lunate and triquetrum distally.
Figure or MRI showing normal TFCC in situ CAPTION: The TFCC is comprised of the
following: (1) the triangular fibrocartilage proper – articular disc; (2) the ulnocarpal
meniscus homologue; (3) the dorsal and vo lar radioulnar ligaments; (4) the floor of the
extensor carpi ulnaris (ECU) tendon sheath; and (5) the volar ulnocarpal ligaments.
(Figures 1 and 2)
The TFCC can be divided logically into three components. The first component of the TFCC is the
triangular fibrocartilage disc itself. This disc accepts and distributes loads to the ulna from the carpus,
much like the way the meniscus of the knee accepts and distributes force from the femur.
Without a TFCC, the force from the carpus that the ulna is able to receive is halved, a deficit that is
compensated by even greater load placed on the radius.
The second component of the TFCC comprise of the radio-ulnar ligaments, which are the primary
stabilizers of the distal radioulnar joint.
The third and final component of the TFCC is the ulnocarpal ligament complex, which prevents dorsal
migration of the distal ulna relative to the lunate and triquetrum, to which it attaches.
The vascular supply of the TFCC is limited to the peripheral 10-40% of the volar, ulnar, and dorsal TFCC
only. The relative hypovascular nature of the central portion of the TFCC precludes healing of injury in
this region, and may necessitate surgical excision of injury with no capacity for repair.
Patient Presentation
Acute injuries of the TFCC result from axial and torsional forces applied to the extended wrist; in short,
most often from falling on an outstretched hand (FOOSH).
Failure of the TFCC may be found in association with a distal radius fracture (which also comes about
from force applied to the extended wrist).
Patients with TFCC injuries may present with chronic complaints of ulnar-sided wrist pain. Often,
symptoms are aggravated with axial loading, particularly with the wrist in extension, or torsional activities
against resistance such as wringing out a washcloth or turning a screwdriver. With progression, even
simple activities such as pouring from a pitcher of water may cause pain.
Pain or tenderness is localized to the ulnocarpal joint and may be provoked with ulnar impaction testing,
or loading through an extended wrist such as with pushing oneself up from a chair. Patients can also
complain of pain in the ulnar wrist in supinated and/or pronated positions.
While the majority of TFCC injuries do not involve instability of the wrist, failure of the distal radioulnar
ligaments may cause instability of the distal radioulnar joint (DRUJ). This instability may cause pain and
mechanical symptoms of “popping” or subtle signs of “giving way”. There may be visible signs of
instability with prominence of the ulnar head relative to the distal radius – often, it is useful to compare the
appearance of both the injured and non-injured wrists for evidence of asymmetry.
clinical of photo of surface anatomy for palpating TFCC
Gross instability of the DRUJ may be recognized with stress testing of the DRUJ in positions of maximal
pronation and supination.
clinical of photo of examination TFCC DRUJ stress testing
Clinical Evidence
For patients with a suspected TFCC injury, advanced imaging studies may be useful in assessment of the
ulnar wrist.
Plain radiographs can show the congruity of the DRUJ and allow measurement of the ulnar variance. (see
“risk factors”, below)
xray showing positive ulnar variance
Arthrography, or, better still, an MRI (or MR-arthrogram) may help detect ulnar wrist pathology. The
sensitivity and specificity for detecting a full-thickness TFCC tear are approximately 85% and 95%,
respectively, for MR-arthrography.
The gold standard for assessing the integrity of the TFCC is arthroscopy, though this is not only an
invasive test, it is one that requires anesthesia.
Injuries of the TFCC can be classified as Palmer Type 1, traumatic, and Type 2, degenerative. Traumatic
lesions may be further sub-classified by their location.
Epidemiology
Attritional tears or degenerative pathology involving the TFCC are common, with a reported incidence of
tears in greater than 50% of those over the age of 60 years. (Such chronic alterations in TFCC may
become symptomatic after minor wrist trauma. On the other hand, the high prevalence of asymptomatic
morphological change within the TFCC makes it unwise to necessarily attribute ulnar-sided wrist pain to a
structural abnormality seen on an imaging study.)
It is estimated that TFCC injury occurs in up to 80% of displaced distal radius fractures.
Differential Diagnosis
It is important to determine whether the symptoms are intrinsic to the wrist, or whether they might be
referred to the wrist from other structures.
Intrinsic causes of ulnar wrist pain which might mimic symptoms associated with a TFCC include:

Arthritis

DRUJ

ulnocarpal joint

pisotriquetral joint

Chondral injury (eg, acute, ulnar impaction)

Fracture:

hook of hamate

pisiform

distal radius

distal ulna

triquetrum

Ganglion cyst,

Kienbock’s disease (avascular necrosis of the lunate)

Inter-carpal ligament injury

ECU tendonitis/pathology
Extrinisic causes include cervical radiculopathy, ulnar neuropathy at the elbow, tendinopathy of either the
extensor or flexor carpi ulnaris. Rarely, a nerve tumor (schwannoma) or ulnar artery thrombosis is the
cause.
The correct inference from the extensive lists above is that TFCC pathology overlaps with many other
conditions and therefore may be blamed when other conditions are responsible, and likewise, may be
cited as the culprit when the true source of symptoms lies elsewhere.
Red flags
Acute traumatic injury to the wrist requires a full evaluation, including the elbow; chronic ulnar sided wrist
pain does have any “red flags” per se
Treatment options and outcomes
Management of TFCC pathology should be guided primarily by the severity of symptoms. Other important
considerations include the acuity and the location of the injury, and the response to initial treatment.
Most injuries of the TFCC may be treated non-operatively: activity modification, immobilization, and
analgesics are first lines of care. Immobilization is typically done above the elbow with limitation of
pronation/supination of the wrist, i.e. long arm removable splint or Munster cast.
For persistent symptoms, corticosteroid injection of the ulnocarpal joint or therapeutic modalities may be
considered.
The potential and indications for TFCC repair are influenced by the vascular anatomy of the TFCC. Acute
or sub-acute injuries to the peripheral TFCC may be amenable to arthroscopic debridement and repair
(arthroscopic +/- limited open repair), whereas central TFCC injuries may be treated with arthroscopic
debridement when conservative management has failed to relieve symptoms.
Occasionally, when arthroscopic debridement does not provide adequate resolution of symptoms, an
ulnar shortening osteotomy (to create negative ulnar variance and in turn decreased ulnar load) may be
needed.
In cases with persistent pain and disability despite appropriate treatment to date, various salvage
procedures may be considered such as joint stabilization, joint unloading or decompression, distal ulna
resection, arthrodesis, and arthroplasty.
In a case series report of “56 patients with triangular fibrocartilage injury (33 patients ….[no] instability of
the distal radioulnar joint) , open repair of the peripheral tear produced 11 excellent, 15 good, 6 fair, and 1
poor result. Repair of peripheral tears restored functional integrity to the triangular fibrocartilage, and
good to excellent results are reported in 26 of the patients treated.”(J Hand Surg Am. 1994 Jan;19(1):14354.Triangular fibrocartilage tears.Cooney WP, Linscheid RL, Dobyns JH).
Among 28 patients with TFCC tears, debrided (and not repaired) one study reported excellent results in
13, good in 8, fair in 2, and poor in 5; from that the authors concluded that arthroscopic debridement of
TFCC tears is “warranted”. (Arthroscopy. 1998 Jul-Aug;14(5):479-83. Wrist arthroscopy for the treatment
of ligament and triangular fibrocartilage complex injuries. Westkaemper JG, Mitsionis G, Giannakopoulos
PN, Sotereanos DG.)
Risk factors and prevention
Ulnar variance describes the relative position of the distal articular surfaces of the radius and ulna.
“Positive” variance referring to the setting in which the ulna projects more distally. The significance of
positive ulnar variance is that the distal ulna and TFCC are subjected to greater loading. Hence, positive
ulnar variance is a risk factor for TFCC injury. (by contrast, negative variance loads the radio-carpal joint
more, and in turn is a risk factor for avascular necrosis of the lunate (Kienbock’s disease )
Miscellany
The term “conservative treatment” should not be used synonymously with “non-operative treatment”.
There is nothing conservative about deferring surgery for a repairable TFCC tear, especially when such a
delay facilitates the transformation of that repairable tear into an irreparable tear.
Some people similarly refer to the “TFCC complex”. This is an instance of the “RAS Syndrome”, a (selfreferential) acronym for the Redundant Acronym Syndrome syndrome in which the word denoted by the
last letter of an acronym is repeated unnecessarily. Other examples include “ATM machine” or “HIV
virus”.
Key Terms
TFCC, triangular fibrocartilage complex, ulnocarpal joint, ulnar wrist
Skills
Create a differential diagnosis of ulnar sided wrist pain and perform a physical examination to hone the
list.