LAUSR

Interphalangeal joint (IPJ) injuries result in significant functional limitations, and remain a challenging problem for the surgeon attempting to restore function and limit post-traumatic degeneration. Dependent upon the fracture configuration, surgical options include open reduction and internal fixation, arthrodesis, implant arthroplasty and osteochondral or perichondral grafts, both vascularized and non-vascularized. Despite these modalities, IPJ injury often results in long-term morbidity. To date, there is a single report in the literature of non-vascularized transfer of partial toe joint autografts for reconstruction of proximal phalangeal unicondylar loss. We present two cases in which a unicondylar osteochondral graft from a toe proximal phalanx was used for IPJ reconstruction. MC, a 51-year-old school principal, sustained an open fracture of the non-dominant left middle finger proximal phalanx with radial condylar loss. Following debridement, MC underwent a left second toe proximal phalanx unicondylar transfer to the left middle finger proximal phalanx. The defect was templated and a corresponding osteochondral graft was harvested from the second toe proximal phalanx radial condyle. The defect was measured intra-operatively and then a slightly larger graft than required was harvested, allowing for in situ adjustment to achieve ideal articular surface contouring. Following harvest, the toe proximal IPJ was arthrodesed by resecting the remaining IPJ surfaces and fixation with two axial 1.1 mm K-wires. The osteochondral graft was secured to the proximal phalangeal head with a single 1.2 mm lag screw (Fig. 1). The patient was splinted post-operatively, and discharged the following day with a CAM boot. He commenced an early mobilization protocol, ranging the middle finger proximal IPJ from 0 to 45° of flexion, and increasing to full motion over 4 weeks. At the 4-month mark, a proximal IPJ range of 30–85° and distal IPJ range of 0–30° were obtained. No pain was reported and grip strength of 30 kg was achieved. The K-wire was removed 6 weeks post-operatively. There were no donor site problems, and radiography at 4 months postoperatively revealed good graft alignment and union. NS, a 21-year-old male non-smoker, sustained an open fracture of his radial condyle of the middle phalanx from a saw (Fig. 2). After an initial debridement, he returned to theatre for a third toe proximal phalanx transfer to the middle finger head of middle phalanx, with a free fasciocutaneous flap to cover the exposed bone. The osteochondral graft was secured with a single bicortical screw, and a volar wrist free fasciocutaneous flap was harvested, and anastomosed to the radial digital artery and a single dorsal vein. The donor was arthrodesed with an axial K-wire, and splinted post-operatively. Following an early mobilization protocol, the range of motion (ROM) improved to full extension with 95° of flexion at the proximal IPJ, and full extension with 40° of flexion at the distal IPJ, at 4 months post-operatively. There was no pain at rest, but mild (2/10) pain on lifting a 25 kg weight. The K-wire was removed 6 weeks post-operatively and the patient returned to work. There were no donor site problems, and radiography at 4 months revealed good graft alignment and union. Injuries of the IPJ may impose significant morbidity. Treatment aims include restoring a functional joint, reducing pain and achieving functional ROM. However, most procedures achieve only one of these goals. IPJ reconstruction is preferable from a similar construct, and toe IPJs provide a practical solution, though there may be a slight dorsal-to-palmar height discrepancy of the donor. Crucial to successful transfer is accurate measurement and precise harvest of the donor condyle, allowing for early mobilization with minimal functional adjustment. While in these cases, the second and third toes were each harvested for osteochondral graft, some of our authors prefer to harvest the third toe in order to preserve the second toe for any potential vascularized transfer. Long-term outcomes may vary, with graft resorption previously reported. However, in those cases, radiography revealed limited Fig. 1. Toe osteochondral graft in finger proximal IPJ prior to fixation, and fixation confirmation with intraoperative radiographic imaging (graft on left of image).