Background: Callus distraction over an intramedullary nail is a
rarely used technique for the reconstruction of intercalary defects of the
femur and tibia after radical débridement of chronic osteomyelitic
foci. The aim of this study was to summarize our experience with distraction
osteogenesis performed with an external fixator combined with an
intramedullary nail for the treatment of bone defects and limb-shortening
resulting from radical débridement of chronic osteomyelitis.
Methods: Thirteen patients who ranged in age from eighteen to
sixty-three years underwent radical débridement to treat a nonunion
associated with chronic osteomyelitis of the tibia (seven patients) and femur
(six patients). The lesions were classified, according to the Cierny-Mader
classification system, as type IVA (nine) and type IVB (four). The resulting
segmental defects and any limb-length discrepancy were then reconstructed with
use of distraction osteogenesis over an intramedullary nail. Two patients
required a local gastrocnemius flap. Free nonvascularized fibular grafts were
added to the distraction site for augmentation of a femoral defect at the time
of external fixator removal and locking of the nail in two patients. At the
time of the latest follow-up, functional and radiographic results were
evaluated with use of the criteria of Paley et al.
Results: The mean size of the defect was 10 cm (range, 6 to 13 cm)
in the femur and 7 cm (range, 5 to 10 cm) in the tibia. The mean external
fixator index was 13.5 days per centimeter, the consolidation index was 31.7
days/cm, and the mean time to union at the docking site was nine months
(range, five to sixteen months). At a mean follow-up of 47.3 months, eleven of
the thirteen patients had an excellent result in terms of both bone and
functional assessment. There were two recurrences of infection necessitating
nail removal. These patients underwent revision with an Ilizarov fixator.
Subsequently, the infection was controlled and the nonunions healed.
Conclusions: This combined method may prove to be an improvement on
the classic techniques for the treatment of a nonunion of a long bone
associated with chronic osteomyelitis, in terms of external fixation period
and consolidation index. The earlier removal of the external fixator is
associated with increased patient comfort, a decreased complication rate, and
a convenient and rapid rehabilitation.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.