Treatment of Excessive Tibial Plateau Angle 257The case example illustrates a patient with a
TPAof 41◦and a safe rotation of 11 mm (S in Fig-
ure 30.1C). Referring to the TPLO chart for a 30-
mm saw blade, a rotation of 10.8 mm is the cor-
rection for a TPA of 26◦. Therefore, a CCWO of
15 ◦combined with a TPLO rotation of 10.8 mm
(TPLO for 26◦+15◦CCWO=correction for pre-
operative TPA of 41◦) would result in a post-
operative TPA of approximately 5◦with a safe
rotation; thus, a CCWO of 15◦was chosen for
this patient (Figure 30.1C). The CCWO is posi-
tioned such that the apex is placed at the caudal
cortical exit of the TPLO (Figure 30.1C).
In cases with significant varus or valgus and
eTPA, the tibial wedge ostectomy can be per-
formed as a biplanar CCWO, rather than as a
coplanar CCWO (Figure 30.3D,E) (Wehet al.
2011), to correct for the angular deformity in
the frontal plane. When performing a bipla-
nar CCWO, the angular correction is typically
performed by angulating the distal limb of the
CCWO (rather than the proximal limb) to avoid
the angled osteotomy from entering into the
radial osteotomy of the TPLO. In cases with sig-
nificant varus or valgus without eTPA, the tib-
ial closing wedge ostectomy can be a coplanar
medial closing wedge (valgus correction) (Fig-
ure 30.3C) or lateral closing wedge (varus cor-
rection) (Figure 30.3B) (Wehet al. 2011). The dis-
tal jig pin beyond (i.e., medial to) the jig arm can
be bent to the angle of correction required, and
this bent pin can be used as a reference for saw
angulation while performing the osteotomy.
Alternatively, a Kirschner wire can be inserted
into the tibia at the desired angle, or an addi-
tional jig pin can be placed and used for a refer-
ence (Wehet al. 2011) (Figure 30.4). In cases with
concurrent tibial torsion, the correction can be
made at the opposing surfaces of the linear tibial
osteotomy; this results in a correction of torsion(A) (B) (C)(D) (E) (F) (G)Figure 30.4 Three-jig pin technique for tibial plateau leveling osteotomy (TPLO) with correction of significant tibial
valgus. The proximal and middle (articulated with distal jig arm) jig pins are placed parallel to the tibial plateau in the
frontal plane, and are parallel to each other (A and B). The third jig pin (distal-most jig pin, not articulated with TPLO jig)
is placed parallel to the talo-crural joint (A and B). The angle formed between the middle and distal jig pins is equal to
the correction angle (B). The TPLO (C) and proximal arm of the medial closing wedge (D) are performed parallel to the
proximal (and/or middle) jig pin. The distal limb of the medial closing wedge is performed parallel to the distal jig pin (E),
creating the medial closing wedge (F). The TPLO jig is re-articulated with the distal jig pin, reducing the medial closing
wedge ostectomy (G), and fixation is applied.