[Intracarpal instabilities].

Intracarpal instabilities result from severe lesions of the ligaments. They present as an anatomico-functional disorganization which may be permanent or intermittent but always carries a high risk for arthrosis. They are usually caused by severe sprains or by dislocations around the lunate bone. All the joints of the wrist can be affected, but lesions of the scaphoid-lunate articulation are the most frequent. The clinical signs of these various instabilities are well known; they consist of pain, snapping and reduced muscle strength--all signs that are suggestive of an internal derangement of the wrist. The radiological signs are specific to each of the anatomical types that may be encountered. An adequate treatment of all instabilities must be instituted as early as possible and in any case before the development of degenerative intracarpal or radiocarpal lesions of the cartilages which would jeopardize the results of any treatment.