314 Surgical Treatment
Gordon-Evanset al. 2013; MacDonaldet al. 2013;
Nelsonet al. 2013; Krotschecket al. 2016). There
is conflicting evidence whether TTA results in
less lameness than the TPLO or LS in the early
postoperative period (<6 weeks) (Ferreiraet al.
2016; Krotschecket al. 2016).
Mid- and long-term clinical outcomes
(>6 months)
A contemporary systematic review evaluated
the scientific evidence on clinical outcomes for
allsurgicalprocedureswithatleast6months
postoperative follow-up, published through
September 2013, to determine if there was evi-
dence to support whether one or more surgical
procedures consistently return a dog to normal
clinical function (Berghet al. 2014). While there
were relatively few studies that met the inclu-
sion criteria, many of them offered high-quality
evidence and, therefore, allowed assessments
of some procedures to be made. Although the
data were not homogeneous, the strength of the
evidence evaluated strongly supported the abil-
ity of the TPLO to allow dogs to regain nor-
mal function postoperatively. In addition, the
evidence supported a superior clinical outcome
after TPLO as compared to LS (Gordon-Evans
et al. 2013; Bergeret al. 2015) (Figure 38.1).
A recent prospective clinical trial compar-
ing TTA, TPLO, LS, and normal dogs using
force plate analysis at a walk and trot at 2 and
8 weeks, and 6 and 12 months postoperatively,
was reported (Krotschecket al. 2016). The TPLO
group gained normal limb use at the 6- and
12-month time points at both a walk and trot,
whereas the TTAregained normal function only
at a walk at the 12-month time point. The LS
group did not regain normal function at the
walk or trot at any time point (Figure 38.2).
Very few studies have reported clinical out-
comes at greater than 1 year after surgery.
However, data suggest that clinical benefits
of surgery persist. Longer-term postoperative
follow-up is important, as surgical procedures
may have either positive or negative long-term
effects on joint biology and biomechanics, and
outcomes may be significantly different than in
the short or intermediate postoperative period.
Mols ̈ a and colleagues (2014) found that a com- ̈
bined group of osteotomy techniques (TPLO,
TTA, triple tibial osteotomy), but not intra-
articular repair techniques, allowed a return to
normal loading (peak vertical force; PVF) at a
minimum of 1.5 years (mean 2.8 years) after
surgery. Auet al. (2010) reported similar PVF
values for the LS and TPLO at 6 and 24 months
after surgery, suggesting that function does not
decline.0102030405060PVF(%BW)LS
TPLOPre-operative6 weeks 12 weeks 6 months 12 monthsFigure 38.1 Canine pelvic limb use at the trot (mean peak vertical force (PVF)×% body weight) measured by a
pressure mat before and after unilateral lateral suture (LS) and tibial plateau leveling osteotomy (TPLO) in a prospective
randomized blinded clinical study. Asterisks indicate significant differences between groups. Data from Gordon-Evans
et al. 2013.