246 Surgical Treatment
(A) (B) (C)(D) (E) (F)Figure 29.2 Illustration of modified cranial closing wedge ostectomy procedure steps. (A) The proximal osteotomy is
scored exiting the cranial cortex∼3 mm distal to the patella tendon insertion point. (B) The distal osteotomy is scored
intersecting the proximal score at∼2/3 the cranial-caudal point of the distal score. The intersection of these scores was
the planned osteotomy angle. (C) The distal osteotomy is completed. (D) The proximal osteotomy is completed exiting
through the distal osteotomy. (E) The osteotomy is reduced by rotating the segments. (F) Reduced osteotomy with
alignment of cranial cortices.
Implant selection
There are many factors that influence implant
selection, and considering all of these and their
interactions is important to reduce the potential
for complications. It is important to realize that
there are very strong forces acting to open the
osteotomy, and the chosen plate must be able
to counter these forces. The primary factor is
the level of the osteotomy; a low osteotomy will
result in a larger proximal fragment and, there-
fore, more screw purchase. To reduce the shift
of the functional axis, the osteotomy is moved
as proximal as is feasible. T-style plates, where
three or more screws are concentrated in an
expanded portion of plate, are helpful for this
purpose. However, plates designed specifically
for TPLO have the screws clustered close to
each other because of the small size of the frag-
ment they must engage. In many of these plates