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V. Villa, A. Madelaine, T. Lording, S. Lustig, E. Servien, P. Neyret
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Discussion
Lateral opening wedge varising distal femoral
osteotomy, performed for symptomatic genu
valgum, has no effect on leg length.
The technique allows satisfactory angular
correction, which is stable over the medium
term. Subjective results are good with a high
rate of patient satisfaction. The rate of
significant post-operative complications was
low, with only two early revisions. We do not
consider removal of internal fixation to be a
complication. There was only two case of
delayed or non union of the osteotomy. The
case of hinge fracture with loss of fixation
occurred in a special case with poor bone
quality. This is the largest series of patients
undergoing this intervention to date. A review
of the literature is summarized in table 1 [6-7-
8-9-10-13-15-18-19].
No previous study has analyzed change in leg
length after distal femoral osteotomy, by either
lateral opening or medial closing wedge
techniques. Using the lateral opening wedge
technique, we have been able to restore a
normal mechanical axis.
The blade plate seems to be a good method of
internal fixation but with a non insignificant
rate of non union. In our study, delayed or non
union occurred in post-traumatic cases with
poor bone quality. To avoid such complications,
technical improvement of the method of
fixation is needed. The non-weight bearing
period may be an important factor in delayed
union, however, there is no consensus in the
literature regarding the optimum postoperative
rehabilitation [12].
This study involved a homogenous group of
patients, operated using the same technique
and rehabilitation protocol. Some limitations
of this study, however, should be noted. The
duration of follow-up in our study is limited
compared with similar studies due to our
limited indications. However, this is the largest
series of patients undergoing this intervention
to date.
We used the new KSS in this study. It is
important to note that this version includes
more items than previously, which may result
in an inferior score. Deformity correction in
varisingdistalfemoralosteotomypredominantly
affects the knee in extension. The effect is clear
in long leg views but unknown in Rosenberg or
flexion views. This is not reported in the
literature nor examined in this study. Further
study is recommended to examine the effect on
the joint line in flexion.
Fig. 4: Kaplan-Meier survival analysis curves with 95% confidence interval.