Influence of soft tissue coverage on the healing of cortical defects in canine diaphyseal bone.

The influence of soft tissue coverage on bone healing was investigated in dogs. A standard diaphyseal bone defect was left open, closed with skin, or closed with skin and muscle. Specimen radiography, callus morphometry, microscopy, and fluorescent microscopy were used to assess bone healing. The defects healed in all groups. Defects left open produced significantly more periosteal callus (p less than 0.01). Abscess formation was observed in the callus. The trabecular structure was abnormally oriented. Histomorphometric measurements of the rate of bone formation were the same regardless of the presence or type of soft tissue coverage. Failure to disturb the intramedullary blood supply may have minimized the differences in healing among the 3 groups. Nevertheless, soft tissue coverage was observed to prevent bone infection and to accelerate the restoration of normal cortical architecture.