- See:
-
Ligaments of the Wrist
-
RU Joint:
- Discussion:
- is ulnar continuation of distal radius & presents concave surface for articulation w/ lunate &
triquetrium;
- ular side of the wrist is supported by the TFCC, which articulates w/ both the lunate and the triquetrum;
- TFCC is prone to injury due to the axial and shear forces that are applied to it as the carpi rotate over the radius and ulna;
- Anatomy and Function of the TFCC:
- Injury to TFCC:
- mechanism of injury includes twisting w/ palmar rotation;
- commonly associated with positive
ulnar variance crepitus, pain, and tenderness between the ulna and triquetrum;
-
ulnocarpal impaction syndrome is a common inciting cause of degenerative tears;
-
mechanism:
- during marked ulnar deviation, compressive load on TFC, particularly w/ positive ulnar variance, may increase markedly;
- forced ulnar deviance, such as batting a baseball, subjects the TFC to heavy loads;
- ref:
Strains in the articular disk of the triangular fibrocartilage complex: a biomechanical study
-
classification:
- central perforations are usually due to degeneration process (most common) - these occur in a minority of cases;
- displacement of the lunate fossa with the TFFC;
- in substance tears of the peripheral rim - peripheral radial attachments are common, and these are amenable to repair;
- include avulsion of TFC from
ulnar styloid - least common, but most amenable to surgical repair;
-
associatted injuries:
- Exam of TFCC Injury:
- Radiographs:
- may reveal avulsion of
ulnar styloid,
scaphoid frx,
distal radius frx, or there may be volar tilt to the lunate and triquetrum (
VISI deformity);
-
ulnar variance: (requires
zero rotation view);
- variable length of the ulna as a positive or negative variance may influence the carpal position;
- wrist w/ more positive ulnar variance tends to be associated with relatively thinner TFC articular disc;
- Triple Injection Arthrography:
- study of choice, but can often miss peripheal meniscus tears;
- identification of tears depends on contrast dye passing thru the radiocarpal and DRUJ;
- MRI:
- normal disc: uniform low signal at both the radial and ulnar attachement;
- complete tear: full thickness discontinuity which extends thru the articular disc;
- references:
- The utility of high resolution MRI in the evaluation of the TFCC of the wrist.
HG Potter MD et al. JBJS Vol 79-A. No 11. Nov 1997. p 1675.
- Non Operative Treatment of TFC Injuries:
- w/ an acute injury placement of forearm in neutral rotation in long arm cast places TFCC in the best alignment for healing;
- marked pronation is to be avoided, because this inclines the ulnar head to displace dorsally;
- supination with imperfect radial fragment reduction may result in palmar subluxation of the ulnar head;
-
steroid injection: often these can confer significant relief of symptoms;
- Operative Treatment of TFCC Injury:
- TFCC repair:
-
ulnar shortening:
- patients w/ a symptomatic perforation and an
ulnar positive variant should be considered for an ulnar shortening
along with the treatment of the tear;
-
ulnocarpal impaction syndrome should be addressed along w/ TFCC tear;
-
wafer procedure:
-
partial excision of TFCC:
- as noted by Menon et al 1997, there is a 30% failure rate of partial TFCC excision when concomitant
ulnar shortening is not performed;
- references:
Partial excision of the triangular fibrocartilage complex articular disk: a biomechanical study.
Isolated tears of the triangular fibrocartilage of the wrist: results of partial excision. J. Hand Surg. 1989. 14-A: 527-530.
Partial Excision of triangular fibrocartilage complex. Palmer AK, Werner FW, Glisson RR, Murphy DJ. J. Hand Surg. 1988: 13-A: 391-394.
Tears of the articular disc of the triangular fibrocartilage complex: results of excision of the articular disc. Imbriglia JE, Boland DS. J. Hand Surg. 1983: 8:620.
Current Concepts Review. Carpal Instability.
Traumatic disruption of the triangular fibrocartilage complex.
Triangular fibrocartilage tears. Cooney WP, Linschied RI, Dobyns JH. J Hand Surg 1994: 19 (1): 143-154.
Triangular fibrocartilage complex lesions: a classification. Palmer AK. J. Hand Surg. 1989; 14-A: 594-606;
Partial excision of the TFCC. AK Palmer, FW Werner, RR Glisson, and DJ Murphy. J. Hand. Surg. Vol 13-A. 1988. p 391-394.
Ulnar shortening combined with arthroscopic repairs in the delayed management of triangular fibrocartilage complex tears.
TE Trumble et al. J. Hand Surg. 1997. Vol 22-A. p 807-813.
