Scaphoid Nonunion Repair With Vascularized Distal Radius Bone Graft
Purpose:
This presentation will demonstrate the technique for scaphoid nonunion repair with vascularized distal radius bone graft.
Case Overview:
The patient is a 29-year-old right-hand–dominant man with chronic pain on wrist extension. He reports that 1 month earlier, he fell onto his right wrist while playing flag football. Imaging is obtained, and he is diagnosed with a scaphoid nonunion with osteonecrosis of the proximal pole. He has pain with activity, notably with wrist extension. The patient is subsequently indicated for scaphoid nonunion repair with vascularized distal radius bone graft.
Method/Technique:
A dorsal incision is made just ulnar to Lister’s tubercle, and dissection is taken down to the extensor retinaculum. The terminal branches of the posterior interosseous nerve are resected and cauterized. A distally based wedge-shaped flap is marked out in the capsule in line with the fourth extensor compartment with identification of the fourth extensor compartment artery pedicle. The donor site for the vascularized bone graft is just ulnar to Lister’s tubercle and 2 to 3 mm proximal to the articular surface of the distal radius. The planned graft is approximately 1 × 0.5 × 0.5 cm.
The capsule is incised; a Kirschner wire is placed 3 cm proximal to the articular surface in the plane of the osteotomy and multiple drill holes are made in the distal radius in the shape of the planned graft. The drill holes are carefully connected with an osteotome, and the graft is delivered, with care taken to protect the capsule and the associated pedicle. The proximal pole nonunion site is identified, reduced, and stabilized. The wrist is hyperflexed and a K-wire placed on the volar aspect of the scaphoid, perpendicular to the fracture. A second wire is placed across the fracture to act as a derotational wire. A cannulated 18-mm micro Acutrak screw is placed across the fracture site.
Next, a high-speed burr is used to create a trough across the dorsal aspect of the proximal and distal fragments, with the proximal fragment noted to be avascular. The graft is then rotated 30° and shaped to fit into the trough. A microfix anchor is placed into the distal scaphoid fracture fragment and the graft is carefully impacted into the trough. The graft is sutured into place via the suture anchor in a pants-over-vest fashion.
Results:
At most recent follow-up, the patient had progressive healing as seen on CT with minimal pain.
Summary:
This technique is an option for repairing scaphoid nonunion with vascularized distal radius bone graft.