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Closing Cranial Wedge

Ostectomy and Triple

Tibial Osteotomy

Simon C. Roe

Closing cranial wedge

ostectomy (CCWO)

Introduction

Closing cranial wedge ostectomy (CCWO) was
the first osteotomy procedure proposed to alter
the forces that act around the stifle and on the
cranial cruciate ligament (CrCL) (Slocum &
Devine 1984). Previously, the technique had
been reported for the management of five dogs
with proximal tibial deformity and cruciate lig-
ament rupture, the idea being that normaliza-
tion of the tibial anatomy would improve stifle
function (Read & Robins 1982). This approach
was later superseded by tibial plateau leveling
osteotomy (TPLO), with the potential advan-
tages that the length of the tibia was not altered
and the osteotomy did not cross the whole shaft
of the bone. However, CCWO continues to be
used by some surgeons, particularly in situa-
tions where TPLO may have an increased risk
of complications. This applies primarily to dogs
that have an excessively steep tibial plateau
angle (TPA), though it may also be considered if

there are associated varus, valgus, or rotational

deformities.

Technique research

It had been assumed that the target TPA for

CCWO was similar to that proposed for TPLO

(6◦), and therefore that the removal of a wedge

that was 6◦less than the measured tibial slope

would result in the appropriate TPA. How-

ever, because the TPA is calculated from the

functional tibial axis (from intercondylar emi-

nences to center of the talus) and that, after

CCWO, the intercondylar notches move cra-

nial relative to their original position, thereby

also shifting the functional axis cranially, a full

correction would not be achieved using this

technique (Baileyet al.2007; Apeltet al.2010).

To minimize this cranial shift (and thus the size

of the wedge that needs to be removed), the

osteotomy should be located as proximally as

possible (while allowing sufficient length for

engaging three screws), and the cranial cortices

should be aligned, rather than simply hinging

the wedge on its apex (which would align the

Advances in the Canine Cranial Cruciate Ligament, Second Edition. Edited by Peter Muir. © 2018 ACVS Foundation.
This Work is a co-publication between the American College of Veterinary Surgeons Foundation and Wiley-Blackwell.

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