Management of stiff hypertrophic nonunions by distraction osteogenesis: a report of 16 cases.
OBJECTIVE
Hypertrophic nonunions can be managed successfully with distraction. Hypertrophic changes indicate that the tissue at the nonunion site has a biologic healing potential. The missing component is an appropriate mechanical environment to transform a hypertrophic nonunion into solid bone.


METHODS
At our institution, the records of 10 male and 6 female patients treated for stiff hypertrophic nonunion with the Ilizarov distraction method were retrospectively analyzed. The average age of the patients was 42.3 years (range 15-69 years). The nonunion time ranged from 8-48 months. All patients had at least 1 cm shortening, 3 patients had a deformity in one plane, and 13 had a deformity in two planes. The pathology was localized to the upper extremity in 5 patients, to the lower extremity in 11 patients, with a periarticular localization in 11 patients. An Ilizarov-type circular external fixator was applied in all patients to correct shortening, to correct deformity, and to achieve a solid union.


RESULTS
All nonunions healed at an average follow-up of 38.1 months (range 24-95 months). The average time spent in the external fixator was 7.1 months (range 5-10 months). The average preoperative length discrepancy was 2.25 cm (range 1-8 cm), which was eliminated in all patients at the time of frame removal. The average coronal plane angulation of 19.7 degrees (range 15-37 degrees) and sagittal plane angulation of 20.8 degrees (range 5-45 degrees), together with translation in one patient, also were corrected to normal anatomic alignment. Complications included minor pin tract infections and hardware problems; recurrence of deformity was observed in one patient who refused to wear a protective brace after frame removal.


CONCLUSIONS
Hypertrophic nonunions can be managed successfully with distraction. The Ilizarov device can address every aspect of a stiff hypertrophic nonunion, including shortening and deformity.
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005599:Fractures, Ununited / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D006984:Hypertrophy; D018889:Ilizarov Technique; D008297:Male; D008875:Middle Aged; D019857:Osteogenesis, Distraction; D012189:Retrospective Studies