Initially described as a procedure for acute scaphoid waist fractures, scaphoid delayed unions have been treated with volar percutaneous screw fixation. Twelve patients underwent this procedure after an average of 12 weeks after injury (range, 6–20 weeks). Some of the major exclusion criteria included tuberosity fracture, scaphoid deformity, DISI deformity, AVN of the proximal scaphoid fragment, or previous wrist injury. Bone resorption or cyst formation at the scaphoid fracture site was not a contraindication to this treatment.
After percutaneous placement of a screw across the fracture site, a short arm thumb spica splint was placed after surgery, replaced 10-14 days later by a short arm spica cast for four weeks. At the 12 month follow up, flexion arc was 94% of the uninjured side; extension arc was 93% of the uninjured side. Grip strength was 92% of the uninjured hand. The mean MMWS was 94 points and the mean DASH score was 9. They had no complications with any of their patients or any evidence of osteonecrosis or osteoarthritis at 12 month follow-up. The authors conclude that in select patients with a delayed union of a scaphoid fracture, volar percutaneous screw fixation can be used as a reliable method for patients to achieve bony union with high functional scores and without major complications. It would seem that these must be truly non-displaced delayed unions without bone resorption or collapse.