The patient was diagnosed with a nonunited proximal pole fracture of the right scaphoid.

Due to the presumed poor vascularity of the proximal pole of the scaphoid, together with the lack of a humpback deformity or lunate extension, she was considered to be a good candidate for a 1,2 intercompartmental supraretinacular artery (ICSRA) vascularized bone graft procedure. The ultimate decision about the vascularity of the proximal pole and the need for a vascularized bone graft, however, would be determined intraoperatively.

A curvilinear incision, paralleling the course of the extensor pollicis longus (EPL), was outlined over the dorsal radial border of the wrist. Gravity exsanguination was used as opposed to an Esmarch bandage to permit 1,2 ICSRA vessel identification . The superficial branches of the radial nerve were identified and protected. The 1,2 ICSRA was identified running along the extensor retinaculum between the 1st and 2nd extensor compartments. It arises from the radial artery approximately 5 cm proximal to the radiocarpal joint and passes beneath the brachioradialis to lie on the dorsal surface of the extensor retinaculum. Distally, the vessels anastomose with the radial artery within the anatomical snuffbox. It is off this distal anastomosis that this reverse-flow vascularized bone graft is based.

The transverse proximal limb of a ligament sparing capsulotomy was then made over the radiocarpal joint to expose the proximal pole of the scaphoid. The fracture site was debrided with curettes and small osteotomes to minimize any thermal necrosis that may be caused by a high-speed burr and the tourniquet deflated to examine the vascularity of the proximal pole. There was scant bleeding from the proximal pole and so a decision was made to stabilize the nonunion and augment this with the 1,2 ICSRA-fed autograft. A partially threaded cannulated headless compression screw was then passed from proximal to distal, preferentially placing the screw volarly to allow the graft to be placed dorsally. Osteotomes were then used to make a box cut dorsally around the site of the scaphoid nonunion to create a space for the vascularized bone graft (Fig. 13.2) .

Attention was then turned to harvesting the bone graft. The 1,2 ICSRA vessel was identified, and the 1st and 2nd extensor compartments were opened radially and ulnarly, respectively, to leave a cuff of tissue around the pedicle of the graft. The vascularized bone graft was centered approximately 15 mm proximal to the joint line to include the nutrient vessels (Fig. 13.3). To achieve this, the proximal vessels leading to the graft were ligated. The distal pedicle was then raised off the extensor retinaculum with care to preserve their integrity as they supply the outlined graft. The graft was elevated using osteotomes, and care was taken to ensure it was not kinked or rotated as it was transposed distally. A small additional wedge cut parallel to one longitudinal border of the graft can help with completing the deep cancellous cut without breaking the graft. With the tourniquet deflated, one can observe pulsatile bleeding from the bone surface. The pedicle and vascularized bone graft were then transposed distally underneath the second compartment tendons. A small amount of cancellous bone graft from the distal radius donor site was first packed into the defect, and then, the 1,2 ICSRA graft was gently tamped and pushed into place dorsally. The distal radius donor site was then packed with bone allograft and the incision closed in layers. A long-arm thumb spica splint was placed .

The patient was immobilized in a long-arm thumb spica cast for 4 weeks postoperatively and then transferred into a short-arm thumb spica cast until union. Given the difficulty associated with determination of osseous union with plain radiographs, and the prolonged average time to union with proximal pole fractures [1–4], a CT scan is obtained at 12 weeks. This showed healing across the fracture site (Fig. 13.4). The patient was then placed into a thumb spica splint and gradually weaned out of this as she advanced her range of motion and strengthening exercises. At 1-year follow-up (Fig. 13.5), she had regained 75 % and 86 % of wrist extension and flexion compared to the contralateral side. Ulnar and radial deviation, as well as grip strength, were symmetrical.