Hinged device for fractures involving the proximal interphalangeal joint.

Well known complications of proximal interphalangeal joint fractures and fracture dislocations are stiffness, chronic instability, and degenerative arthritis. The Compass PIP Hinge is a dynamic external fixator that allows protected proximal interphalangeal mobilization after closed reduction, open reduction and internal fixation, volar plate arthroplasty, or other salvage procedures. To help avoid these problems, 20 patients, 12 treated within 2 weeks of injury (Group I) and 8 treated more than 4 weeks after injury (Group II), are reported. Articular surface involvement among Group I cases averaged 66% (range, 50%-90%), and postoperative proximal interphalangeal motion for this group averaged 9 degrees to 82 degrees. Mild pain with heavy use was present in 3 patients, and 9 patients were pain free. Postoperative proximal interphalangeal motion for Group II averaged 21 degrees to 77 degrees. Pain was moderate to severe in 2 patients, mild with heavy use in 1 patient, and none in 5 patients. One patient from Group II underwent surgery to convert to a silicone proximal interphalangeal arthroplasty because of painful degenerative arthritis. It is concluded that there is a role for hinged external fixation in treating unstable proximal interphalangeal fracture dislocations. Outcomes in acute injuries are superior to those in chronic or salvage cases.