Background:
Femoral lengthening over an intramedullary nail has been described
in adults. A technique of femoral lengthening over a humeral intramedullary
nail in children is described, and the results and complications
are presented.
Methods:
Nine preadolescent patients (average age, nine years and ten months)
with femoral length discrepancy were treated with femoral lengthening
over a humeral intramedullary nail. After nail insertion, a monolateral
external fixator was placed with half-pins either anterior or posterior
to the intramedullary nail, and lengthening was performed through
a proximal osteotomy.
Results:
The femora were lengthened a mean of 6.1 cm (range, 5.0 to 8.0
cm), 19.5% (range, 15.9% to 26.2%) of the preoperative femoral length.
Patients had a mean lengthening index of 12.2 days/cm of length
(range, 9.5 to 16.9 days/cm of length). Five complications including
osteomyelitis, failure of the distal interlocking site, and femoral
fracture at the distal end of the nail occurred in four patients;
four of the complications led to surgical intervention. No case
of proximal femoral valgus secondary to nailing through the greater
trochanter had developed by the time of final follow-up. All patients
were followed for a minimum of two years postoperatively, with a mean
of 128 weeks (range, 111 to 161 weeks).
Conclusions:
The technique is effective but has a high rate of complications,
including osteomyelitis, which developed in two of the nine patients.
No avascular necrosis or proximal femoral valgus was noted.