Abstract:
The aim of the study is to determine the outcomes
in patients who underwent conversion from an
external fixator to an internal fixation device. This is a retrospective
review of 18 patients (24 limbs) who underwent
conversion from external to internal fixation. The patients
had external fixators applied for traumatic bone defects or
congenital deformities. Conversion to internal fixation was
performed for reasons of patient dissatisfaction with external
fixation, pin track sepsis, persistent non-union or refracture.
The complexity of cases was graded using Paley’s level of
difficulty score. Patients were either converted acutely or
delayed. Internal fixation devices were either intramedullary
nails or plate and screws. Outcome was regarded as excellent
if the patients were fully weight-bearing and pain-free on a
mechanically well-aligned limb and without need for further
surgery: good if the patient required subsequent surgery to
achieve union and poor if irreversible complications occurred.
Acute conversions (fixator removal and introduction of
internal fixation device at same surgery) were done in 19
limbs and delayed conversion (interval between fixator
removal and internal fixation) in 5. In the acute group, 17
limbs (89.4 %) had at least a good outcome, 16 of these
limbs had an excellent result. Two limbs (10.6 %) had a poor
result and required amputation. Both cases were after acute conversion to intramedullary nails; the original presenting
diagnosis was of an infected non-union of the tibia and both
had Paley scores above 7. In the delayed conversion group,
all limbs (100 %) had at least a good outcome, with 4 limbs
(80 %) having an excellent result. The mean external fixator
time was 185 days (61–370). Both the cases with poor outcomes
had longer external fixation times. This series supports
the practice of conversion of external fixation to
internal fixation with the majority of patients attaining good
results. It identifies that plate devices appear to produce
fewer deep sepsis complications, as compared to intramedullary
nails, particularly when the original presenting diagnosis
is a septic non-union.
