Advances in the Canine Cranial Cruciate Ligament, 2nd edition

(^36) Meniscal Release
Antonio Pozzi and James L. Cook
Introduction
Meniscal pathology is commonly reported in
conjunction with cruciate ligament rupture
(CR) (Flo 1993; Williamset al.1994; Ralphs &
Whitney 2002; Lutheret al.2007), or at some
point after surgical treatment of the cranial
cruciate ligament (CrCL)-deficient stifle joint
(Metelmanet al. 1995; Thiemanet al. 2006;
Lafaveret al.2007; Caseet al.2008). Chronic
stifle instability resulting from CR causes supra-
physiologic loading of the menisci, particularly
shear and compression of the caudal pole of the
medial meniscus, resulting in meniscal tears.
When surgical treatments do not fully restore
stifle kinematics, as is the case for the majority
of surgical procedures, the menisci are still at
risk after treatment. Meniscal pathology noted
at the time of initial surgery is termed ‘concur-
rent’ or ‘coincident,’ and when diagnosed after
surgery it is said to be ‘subsequent,’ ‘latent,’ or
‘postliminary.’ Concurrent meniscal pathology
is recognized in between 20% and 77% of cases
(Flo 1993; Williamset al.1994; Ralphs & Whit-
ney 2002; Mahnet al.2005; Lutheret al.2007),
while subsequent meniscal injury is recognized
in between 3% and 100% of cases (Metelman
et al.1995; Slocum & Slocum 1998; Thieman
et al.2006; Lafaveret al.2007; Caseet al.2008). It
has been suggested that some cases diagnosed
as subsequent meniscal tears may in fact have
been concurrent tears that were misdiagnosed
(latent tears). The rest of the subsequent tears
that occur after CR surgery are called postlim-
inary tears. Because subsequent tears are often
associated with pain and lameness and necessi-
tate a second surgery, veterinary surgeons have
aimed for improved diagnostic approaches to
meniscal disease in dogs (see Chapters 18, 19,
20, and 21) and strategies for prevention of sub-
sequent meniscal pathology in a comprehensive
approach to treatment of CR.
One strategy designed to prevent subse-
quent meniscal injuries is release of the medial
meniscus by radial transection at the caudal
meniscotibial ligament of the medial menis-
cus (caudal release) or at the midbody of the
medial meniscus. Medial meniscal release is
theorized to free the caudal pole from expo-
sure to the abnormal loads delivered during
weight-bearing in the CrCL-deficient canine
stifle joint (Slocum & Slocum 1998; Kennedy
et al. 2005; Pozzi et al. 2006). The clinical
goal of meniscal release is to eliminate any
impingement of the meniscus between the
femoral and tibial condyles, described as the
‘wedging phenomenon’ (see Chapter 4), and in
doing so decrease the likelihood of subsequent
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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