Injury to collateral ligament of the metacarpophalangeal joint of a finger.

Twenty-two patients with injury to the collateral ligament of the metacarpophalangeal (MP) joint of a finger are reported. Thirteen cases were acute injuries and nine cases were chronic injuries. In all cases arthrography was performed. The arthrographic findings correlated with the grade of joint stability. Arthrographics of the unstable joint gave useful information for elucidating the mechanism of injury and deciding whether surgical treatment was indicated. At exploratory surgery, a Stener lesion was identified in one case in which the ruptured end of the ligament was trapped by the proximal portion of the expansion hood and sagittal band.