Advances in the Canine Cranial Cruciate Ligament, 2nd edition

(^4) Meniscal Structure and Function
Antonio Pozziand James L. Cook
Surgical anatomy
The menisci are crescent-shaped wedges of
fibrocartilage that rest on the peripheral aspects
of the articular surfaces of the proximal tibia.
They function to effectively deepen the medial
and lateral tibial fossae for articulation with the
condyles of the femur (Figure 4.1). They are
thickest abaxially and taper to thin, unattached
edges axially. The superior femoral surfaces are
slightly concave to accommodate the femoral
condyles, thus providing greater articular con-
tact area and improved stifle joint congruity. In
dogs, the medial meniscus is larger than the lat-
eral and more ovoid in shape. The lateral menis-
cus is smaller and more circular (Hulse & Shires
1983; Arnoczky 1993; Evans 1993; Carpenter &
Cooper 2000).
Both medial and lateral menisci have attach-
ments that influence their mobility and func-
tion (Figure 4.2). The medial meniscus is firmly
attached to the tibia through cranial and caudal
menisco-tibial ligaments. Strong attachments
are also present between the abaxial aspect of
the medial meniscus and the medial collateral
ligament. The abaxial periphery of the medial
meniscus is also attached to the joint capsule
via short ligaments that blend with the joint
capsule (sometimes referred to as the coronal
ligaments). A cranial menisco-tibial ligament
anchors the lateral meniscus to the tibial plateau
caudo-lateral to the cranial cruciate ligament
(CrCL). Small caudal menisco-tibial ligament(s)
may or may not be present in dogs, and can be
attached cranial or caudal to the caudal cruci-
ate ligament (CaCL) attachment when present.
The lateral meniscus differs from the medial
meniscus, however, in that the caudal pole of
the lateral meniscus is attached firmly to the
femur through the menisco-femoral ligament,
which attaches onto the caudo-medial aspect of
the intercondylar notch, caudal to the CaCL. In
addition, the abaxial border of the lateral menis-
cus lacks a firm attachment to the lateral collat-
eral ligament or joint capsule, and instead forms
a groove where the popliteal tendon slides
between the meniscus and joint capsule dur-
ing stifle motion. The resultant mobility of the
lateral meniscus helps to explain the decreased
incidence of severe lateral meniscal tears con-
current to CrCL insufficiency when compared
to the medial meniscus in dogs (Ralphs & Whit-
ney 2002). The intermeniscal or transverse lig-
ament connects the cranial poles of the lat-
eral and medial menisci, and blends with fibers
from the cranial menisco-tibial ligaments. The
intermeniscal ligament lies just cranial to the
tibial attachment of the CrCL and is covered
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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