Lesser digital fusion with a cannulated screw

Abstract

A dorsal linear longitudinal approach is used to access both the proximal interphalangeal joint (PIPJ) and distal interphalangeal joint (DIPJ). A transverse tenotomy/capsulotomy to enter the PIPJ and DIPJ is next employed. A planar resection of the opposing PIPJ joint surfaces is performed. The cannulated screw guide wire is driven from the head of the middle phalanx through the middle phalanx across the PIPJ, through the proximal phalanx, and across the metatarsophalangeal joint (MTPJ) into the lesser metatarsal head. Typically, a 24-mm-long cannulated screw is driven from the head of the middle phalanx across the fusion site into the shaft of the proximal phalanx. As the screw is driven, compression is visualized across the fusion site and “2-finger tightness” of the screw is achieved. The guide wire is then removed. Once seated, the screw-head surface should sit flush with the articular surface of the head of the middle phalanx (Fig 1). Depending on the girth of the digital bones, a 2.0-mm to 3.0-mm diameter screw is used. Additional tendinous or capsular releases of the MTPJ or DIPJ are performed as indicated. The patient may be full weightbearing in a surgical shoe immediately postoperatively, with a half-inch piano-felt liner from heel to sulcus if a Kirschner wire is crossing the MTPJ. The protective shoe is maintained for approximately six weeks. In cases in which temporary postoperative stabilization of the MTPJ is required, such as in flexor digitorum longus tendon transfers or flexor plate repairs, a cannulated screw