In a follow-up examination 50 patients who had sustained dorsal dislocations of the proximal interphalangeal (PIP) joint, the results of two conservative therapy regimens, either immobilisation or early motion, were investigated. The patients were assigned randomly. The inclusion criteria were: adult patients over the age of 18 with isolated, acute, closed dorsolateral dislocation of the PIP joint.
In group A, 25 patients were treated by closed reduction and immobilisation with a short-arm cast including both interphalangeal joints for 4 weeks. In group B, 25 patients were treated by dorsal block splinting of the PIP joint following reduction. The finger was released in extension with daily active exercise of the PIP joint.
In group A, 9 patients showed a normal range of motion, whereas a limitation of extension of 10 deg and more was seen in 16 patients. All PIP joints were clinically stable, and 19 patients were satisfied. Two patients complained of a limitation of extension, 3 of limitation of extension and pain, and 1 of pain and swelling. In group B, only 2 of 25 patients showed a limitation of extension of 10 deg and more, whereas 23 patients showed a normal range of motion. Instability of one collateral ligament was seen in 2 cases. Palmar instability did not occur, and 18 patients were satisfied. One patient complained of instability, pain and lack of extension during hard work, 1 of pain in combination with instability, 2 of pain and 3 of swelling of the joint.
Early active motion after dorsolateral dislocation of the PIP joint produces significantly superior results regarding the active range of motion and pinch power than static splinting.