- Discussion:
- finding include hypertrophy of bone ends & sclerosis at 6 months post injury;
- these non unions theoretically have sufficient vascularity to heal but stability is lacking or normal axial alignment has not been restored;
- it is important to point out, however, that even with the radiographic appearance of a "classic" hypertrophic nonunion, vascularity may be impaired;
- non union results from mechanical problem of poor fixation or reduction as well as possible diminished vascularity;
- compared to atrophic nonunion, the hypertrophic nonunion has better biologic propensity to heal;
- when stability & good axial alignment are established, hypertrophic non unions will usually heal in a relatively short period of time;
- Radiographs:
- Treatment:
- hypertrophic nonunions of tibia w/ intact fibula may be treated w/ partial fibulectomy (1-2 cm)
and full weightbearing in plaster cast;
- if fracture vascularity is not comprimised and bony sclerosis is not excessive, then expect success rate of > 75;
- disadvantages:
- may increase tibial fracture instability, and may be contra- indicated w/ fracture angulation;
- may interfere w/ future posterolateral bone grafting;
- application of bone graft is not necessary for these fractures to heal;
- in contrast, hypotrophic nonunions require bone grafting along w/ stabilization inorder to heal;
- alternatively hypertrophic nonunions will go on to heal w/ application of rigid fixation (plate, an intramedullary nail, or an external fixator);
- if fractured fragments are adequately aligned, debridement of the non-union, is not required