The Triangular FibroCartilage Complex, or TFCC, is an important structure in the wrist. The TFCC is made of tough fibrous tissue and cartilage. This tissue supports the joints between the end of the forearm bones (radius and ulna), adding to their stability. The TFCC also helps connect the forearm with the small bones in the ulnar side (“pinky finger” side) of the wrist. There are several different tissues that form the TFCC, and they blend together to stabilize the ulnar side of the wrist.
The TFCC also acts as a cushion between the end of the ulna and small bones (lunate and triquetrum) of the wrist (Figure 1). In patients whose ulna is longer than the radius at the wrist, the TFCC is usually thinner and more likely to tear.