Comminuted diaphyseal fractures of the radius and ulna: does bone grafting affect nonunion rate?

BACKGROUND:
The recommendation of Anderson and colleagues to bone graft even relatively minor amounts of comminution (a third of the bone diameter) in the treatment of diaphyseal forearm fractures with plate-and-screw fixation has been questioned. This study examines factors related to nonunion in adult patients with comminuted diaphyseal fractures of both the radius and the ulna to determine the relative influence of bone grafting.

METHODS:
Over a 15-year period at two hospitals, 41 patients with diaphyseal fractures of both forearm bones satisfied the following criteria: comminution (Orthopaedic Trauma Association grade IV or higher) of at least one fracture; treatment with 3.5- or 4.5-mm dynamic compression plates at least six holes in length; and minimum 12-month follow-up. Multiple logistic regression was used to determine the contribution of the following factors to the risk of nonunion: multiple injuries; ipsilateral upper extremity injury; open wound; and the application of cancellous bone graft at the fracture site.

RESULTS:
Five patients had nonunion of one or both bones (12%). According to the multiple logistic regression model, none of the factors studied had a statistically significant association with nonunion (p > 0.40 for all). The odds ratios were as follows: multiple injuries, 2.1 (95% confidence interval [CI], 0.34-12.9); ipsilateral injury, 0.68 (95% CI, 0.058-7.84); open fracture, 1.46 (95% CI, 0.21-9.89); and bone graft, 0.98 (95% CI, 0.15-6.42).

CONCLUSION:
Nonunion occurred in 12% of comminuted, diaphyseal fractures of both bones of the forearm treated with dynamic compression plates. No single factor was associated with nonunion. In particular, the use of bone graft was not associated with a higher rate of union.