[Joint lesions of the first column of thumb]

Lesions involving the thumb from the interphalangeal joint to the trapezo-metacarpal (TM) joint are very frequently the result of sports injuries. The authors discuss the most frequent lesions: 1) Dislocations of the metacarpo-phalangeal (MP) joint of the thumb which can be reduced in almost every case by means of well conducted orthopaedic manoeuvres. 2) Sprains of the MP joint of the thumb, very common lesions the severity of which must not be underestimated and which always require surgical treatment in the serious lesions, regardless of the compartment involved (radial or ulnar). 3) Bennett's fractures or fracture-dislocations of the TM joint; when neglected inadequately treated, these lesions lead to disabling post-traumatic arthritis of the TM joint. A poor result of treatment for any one of these three lesions always compromises opposition of the thumb and/or the strength of pollico-digital grip.