298 Surgical Treatment
(A) (B)1
23Figure 35.2 Illustrations of caudal (A) and central radial (B) transections of the medial meniscus for meniscal release in
dogs. 1, Gerdy’s tubercle; 2, popliteal tendon; 3, caudal menisco-tibial ligament of the medial meniscus. The radial
incision for the central release is made just behind the medial collateral ligament, with the blade aligned with Gerdy’s
tubercle. Copyright©Samantha J. Elmhurst atwww.livingart.org.uk.
tissue should appear smooth, white, and glis-
tening and not be readily displaced, folded,
separated, or penetrated with a blunt arthro-
scopic probe. Abnormal meniscal tissue is typi-
cally soft, fibrillated, discolored and abnormal
in location, architecture, and integrity, and is
often associated with local articular cartilage
damage. Taken together, these variables help to
distinguish pathologic from functional menis-
cal tissue and guide the surgeon in determining
what to resect and what to preserve.
Meniscal release, or radial transection, is the
other procedure commonly performed in dogs
for the treatment or attempted prevention of
meniscal injuries. The rationale behind menis-
cal release is that the surgeries performed to sta-
bilize CrCL-deficient stifles do not consistently
restore normal kinematics, and, therefore, the
medial meniscus remains at risk of subsequent
damage with intermittent or periodic caudal
femoral subluxation (Kimet al. 2012). Accord-
ingly, the meniscus can be released at the time of
the stifle stabilization procedure, allowing it to
displace caudally with the femoral condyle and
prevent subsequent damage, tearing, and asso-
ciated lameness. In this way, the need for addi-
tional surgery to treat post stifle-stabilization
meniscal tears can be minimized. Importantly, it
has been suggested that many meniscal injuries
diagnosed after the initial surgery for CR may
instead be tears that were present, but unde-
tected, at the original surgery (Metelmanet al.
1995; Thiemanet al. 2006). This further high-
lights the importance of careful inspection and
probing of the menisci during the first surgical
procedure.
Radial transection for medial meniscal release
can be performed at the caudal meniscal horn–
caudal meniscotibial ligament junction (caudal
release), or at the mid-body of the meniscus
(central release) via arthroscopy or arthrotomy
using scalpel blades (#11, #15, or Beaver blades)
or meniscal knives (Figure 35.2). While menis-
cal releases can be associated with a signifi-
cantly lower risk for clinically apparent sub-
sequent meniscal tears (Thiemanet al. 2006;
Ritzoet al. 2014), radial transection of the menis-
cus, regardless of location, completely disrupts
the circumferential collagen fiber integrity (rim)
and destroys critical meniscal functions (Pozzi
et al. 2006; Pozziet al. 2008b; Luther et al.
2009). The released menisci will not function-
ally heal and will remain biomechanically defi-
cient (Cooket al. 2016). Meniscal release alone
in CrCL-intact stifles in dogs results in artic-
ular cartilage loss, further meniscal pathology,
osteoarthritis, and lameness within 12 weeks
(Lutheret al. 2009). In clinical patients with
CR, however, clinically significant differences
in outcome between groups receiving or not
receiving meniscal release have not been noted
based on subjective assessments (Thiemanet al.
2006; Ritzoet al. 2014). As such, the present
authors suggest that meniscal release can be jus-
tified when the meniscus cannot be full assessed
for pathology, cannot be sufficiently resected
safely, or the subsequent meniscal tear rate is
unacceptably high to the surgeon or the client.