- See:
Ligaments of the Wrist
- Anatomy of TFCC:
- consists of articular disc (triangulyar fibrocartilage), meniscus homologue (lunocarpal), ulnocarpal
ligament, dorsal & volar radioulnar ligament, and
ECU sheath;
- it originates from firm attachments on medial border of distal radius and inserts into the base of the
ulnar styloid;
- it 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;
- vascular anatomy: only the peripheral 15-20% of the TFCC has a blood supply;
-
ligamentous attachements: (see
ligament of the wrist)
- ulnar attachment of the TFCC is anchored by two bands inserting to the styloid process and fovea (base of the styloid);
- volar ulnocarpal ligaments run from the base of the ulnar styloid process across the volar surface of the TFCC, and then insert on the lunate and triquetrum;
- ulnocarpal ligaments include:
- volar ulnolunate:
- ulnotriquetral ligaments:
- these ligaments prevent dorsal migration of the distal ulna;
- because the ulnar styloid moves away from the carpi in supination, these ligaments are more taught in supination;
-
blood supply:
- central disk is avascular;
- peripheral vessels penetrate approximately 10-40% of the TFCC margins;
- Function:
- TFCC is main stabilizer of distal radioulnar joint, in addition to contributing to ulnocarpal stability;
- its important in loading & stabilizing of distal
radioulnar joint;
- TFCC normally not only stabilizes the ulnar head in sigmoid notch of radius but also acts as a buttress to support proximal carpal row;
- during axial loading, the radius carries the majority of load (82%), and the ulna a smaller load (18%);
- increasing the ulnar variance to a positive 2.5 mm increases the load transmission across the TFCC to 42%;
- w/ the TFCC excised, the radial load increases to 94%;
-
stabilizing role: (see
DRUJ instability)
- volar TFC prevents dorsal displacement of ulna and is tight in pronation;
- dorsal TFC prevents volar displacement of ulna and is tight in supination;
An anatomic study of the ligamentous structure of the triangular fibrocartilage complex. S. Ishii MD et al. J. Hand Surg. Vol 23-A. 1998. p 977-985.
The triangular fibrocartilage complex: an important pulley for the ulnar wrist extensor. JB Tang MD et al. J. Hand Surg. Vol 23-A. 1998. p 986-991.
The microvasculature of the triangular fibrocartilage complex: Its clinical significance. Bednar M, Arnoczky S, Weiland A: J Hand Surg Am 16:1101-1105, 1991
Histologic anatomy of the triangular fibrocartilage. Chidgey L: Hand Clin 7:249-262, 1991