CHICAGO — Researchers achieved good results for scaphoid waist nonunions with collapse using open reduction and internal fixation and pure cancellous interposition graft, according to a study presented at the American Society for Surgery of the Hand 2012 Annual Meeting.
“This appears to be a viable option for the scaphoid waist nonunion with collapse,” study presenter Mark S. Cohen, MD, said. “The main prerequisite is that you need an adequate sized proximal and distal fragment to accept screw purchase and maintain the reduction. It is analogous to what we are doing for many distal radius malunions. We are placing a fixed angle device anteriorly, whereby the placing hinged reduction of the bone and the dorsal cavity is simply filled with pure cancellous graft.”
Cohen and the researchers employed this method in 12 patients with an average age of 22 years. Each patient underwent CT scans to measure the degree of collapse and bone loss. The researchers conducted open reductions anteriorly to place the distal to proximal screw and filled defects with pure cancellous autograft harvested from the ipsilateral distal radius. Patients were followed up at 3.5 years.
The researchers noted wrist extension and grip strength improved significantly from presentation to follow-up. The visual analog scale score for pain averaged less than one. The Mayo Wrist score was 88 out of 100. All of the wrists united with no loss of reduction or wrist function.
Cohen stressed the superiority of this method over the gold standard of structural corticocancellous bone graft.
“I think the biggest benefit of this procedure is the simplified carpentry,” Cohen said. “No longer am I working with an 8 mm trapezoidal graft to trim, cut and fit into a deep hole within the scaphoid waist. The reduction is maintained with provisional pins. Then the defect, regardless of size, shape or geometry is simply filled with pure cancellous bone taken from the ipsilateral local wrist. Cancellous bone seems to incorporate more rapidly than cortical cancellous bone and, at least in this small series, it does not seem to compromise maintenance of the ultimate reduction and the ultimate function of the wrist.”
Cohen MS, Fallahi K, Shukla SK. Scaphoid non-union with humpback deformity treated without structural bone graft. Paper #33. Presented at the American Society for Surgery of the Hand 2012 Annual Meeting. Sept. 6-8. Chicago.
Disclosure: Cohen receives research or institutional support and royalties, non-cash support, honoraria or other funding from Integra and has a current or proposed employment or consulting arrangement with Mylad.