What is the TFCC? The triangular cartilage complex (TFCC) of the wrist consists of the articular disc, dorsal and palmar ulnar radial ligaments, meniscal-like material, ulnar collateral ligaments, and the tendon sheath of the ulnar extensor carpi radialis tendon, among other structures. What is the role of the TFCC? It is responsible for loading the wrist joint and maintaining stability of the lower ulnar radial joint. What are the signs of a TFCC injury? It is a common cause of ulnar pain in the wrist, mostly chronic, and is often negative on x-ray. MRI can aid in the diagnosis (Potter found that MRI has a diagnostic sensitivity rate of 100%, an accuracy rate of 97%, and a localization accuracy rate of 92%). Typical symptoms are pain on the ulnar side of the wrist, or with popping. It can be aggravated by clenching a fist or moving the wrist ulnarly. Pressure pain in the ulnar joint space is obvious, and the wrist ulnar grinding test is positive (pain is felt during dorsal extension, axial loading, and ulnar rotation of the wrist joint). In some patients with carpal navicular fractures and distal radius fractures, the symptoms of TFCC injury are often masked by the symptoms of the fracture The mechanism of injury is anterior rotation and extension of the forearm during a fall with rotational and longitudinal injury. Sometimes, but less frequently, ulnar pulling of the wrist joint can also cause a TFCC injury. What is the treatment for a TFCC injury? Treatment depends on the presence of wrist pain (including mechanical irritation due to injury or persistent joint pain due to synovitis), the presence of an associated fracture or fracture malunion, and the presence of distal ulnar radial instability. If the patient’s history and examination are suggestive of a TFCC injury, the x-ray is normal, and there is no clinical evidence of instability, the acute phase can be immobilized with a long-arm cast or brace for 4-6 weeks. Occasionally, physical therapy can be applied. If there is no relief of symptoms after immobilization, further investigations, such as MRI and arthroscopy, are required. Indications for arthroscopic surgery: those with TFCC injuries for which conservative treatment has failed; those with instability of the lower ulnar radial joint; if the patient is radiologically or clinically unstable, early arthroscopic evaluation should be considered and repair should be performed. Modalities of surgical treatment: depends on the type of injury. In general, for traumatic central type injuries, arthroscopic debridement can yield good results if the injury does not involve the dorsal palmar ligament and does not affect the function of the TFCC. For TFCC peripheral tears, arthroscopic repair can be performed. If combined with factors of ulnar wrist impingement, simultaneous surgical management is required. For degenerative TFCC injuries, most of which are secondary to ulnar impingement, generally speaking, these injuries cannot be surgically repaired by the TFCC itself, but good results can be obtained by treating the cause of degeneration. Current surgical treatments include ulnar shortening, arthroscopic or incisional wafer surgery for degenerative TFCC, softened cartilage, torn ligaments, joint capsule scarring and synovial debridement.