196 Surgical Treatment
ES suture may be different for individual dogs,
depending on conformation (Witte 2015).
Clinical outcome
Extracapsular stabilization techniques gener-
ally have good outcomes, particularly subjec-
tively. The most common major complications
associated with ES procedures are postoper-
ative meniscal tear, failure of the stabiliza-
tion, and implant-associated infection (Dulisch
1981; Korvicket al. 1994; Chauvetet al. 1996;
Conzemius et al. 2005; Guen ́ ego ́ et al. 2007;
Casale & McCarthy 2009; Ertelt & Fehr 2009;
Cooket al. 2010; Christopheret al. 2013).
After LFTS, owners are reportedly satisfied
with outcomes in 82–90% of cases (Moore &
Read 1995; Chauvetet al. 2009). Minimal to
no lameness was reported in 78–82% by 6–20
months’ follow up in most studies (Moore &
Read 1995; Chauvetet al. 1996; Ertelt & Fehr
2009), although one study reported only 40%
clinical improvement by 6 months (Conzemius
et al. 2005). On palpation examination, 55–76%
of dogs had no drawer palpable at 6–20 months
after surgery (Moore & Read 1995; Chauvetet al.
1996; Ertelt & Fehr 2009), and 73% had no pain
on stifle manipulation at 20 months postopera-
tively in the 11 dogs that returned for follow-up
(Moore & Read 1995).
Force plate examination is a more objec-
tive measure of outcome, and has been used
in multiple studies of clinical outcome after
LFTS and has shown less satisfactory results
than the previously discussed subjective out-
come measures. One study reported that only
15% of dogs achieved normal ground reaction
forces within 6 months (Conzemiuset al. 2005),
another reported that 86% returned to normal
by 20 months after surgery (Chauvetet al. 1996),
while a third study reported that dogs treated
with LFTS remained significantly different from
normal throughout the study period of one year
(Nelsonet al. 2013).
The most recent evidence has shown tib-
ial osteotomy procedures, particularly the tib-
ial plateau leveling osteotomy, to have supe-
rior outcomes when compared to ES (Lazar
et al. 2005; Gordon-Evans et al. 2013; Nel-
son et al. 2013; Bergh et al. 2014), though
there are also studies showing no difference in
outcome between ES and osteotomy procedures
(Conzemiuset al. 2005; Auet al. 2010; Cooket al.
2010; Mols ̈ a ̈et al. 2013).
Major postoperative complications report-
edly occur in 7–17% of LFTS cases and include
implant infection, swelling or irritation associ-
ated with the implant, implant failure, tearing of
the fabellofemoral ligament, meniscal tear, fail-
ure to control stability, and peroneal nerve dam-
age (Dulisch 1971; Casale & McCarthy 2009;
Ertelt & Fehr 2009; Auet al. 2010). In one
study, the risk of development of complications
after LFTS was increased in dogs that were
male, had a higher body weight, or were of
younger age (Casale & McCarthy 2009). When
multifilament suture is used for LFTS, the risk
of fabellofemoral ligament failure is increased
(Lodatoet al. 2013), as is the risk of infec-
tion (Korvicket al. 1994). The risk of infection
when using multifilament suture may be fur-
ther increased with decreased surgeon experi-
ence (Dulisch 1981).
Literature reporting clinical outcomes for
techniques other than the LFTS is sparse. In
the largest study of long-term outcome after
clinical cases of CR treated with TR, owners
reported a return to full function in 76% of
dogs (60/79) and a return to acceptable func-
tion in 23% (18/79), with 44% (35/79) still
experiencing some degree of pain (Christopher
et al. 2013). Major complications occurred in
8.9% of stifles (7/79), with the primary major
complication being postoperative meniscal tear
(6.3%; 5/79). Other major complications were
not detailed (Christopheret al. 2013). In another
clinical study, 92% of dogs (48/52) had a suc-
cessful outcome more than one year after TR
surgery based on follow-up via phone conver-
sation (Ritzoet al. 2014). The outcome was more
likely to be successful if a concurrent meniscal
tear was diagnosed and treated at the time of
initial surgery (Ritzoet al. 2014).
Owner assessment of outcome after ES using
bone anchors is also good, with 92–100% owner
satisfaction at 10–18 months after surgery
(Gu ́en ́egoet al. 2007; Hulseet al. 2011). At
18 months’ follow-up, one study reported that
lameness had been resolved in 91% (44/48) of
dogs (Guen ́ ego ́ et al. 2007). Despite good sub-
jective outcome, radiographs revealed that the
bone anchors had pulled out of the femur in
21% of dogs (10/48) in this study (Guen ́ ego ́