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Regenerative Medicine and

Cranial Cruciate Ligament

Repair

Gabriel S. Perrone,Martha M. Murray, and Patrick Vavken

Introduction

In the 5 years since the First Edition of this
book was published, the amount of research
on treating the cranial cruciate ligament (CrCL)
in dogs has substantially increased. Approxi-
mately 25% of the entire CrCL-related litera-
ture in the databases of the National Library
of Medicine has been published since 2010
alone. However, while many questions have
been answered, others have emerged. In par-
ticular, attention has begun to shift from not
only recreating stability but also to preventing
an accelerated onset of osteoarthritis (OA).

Current surgical treatments and their

comparative effectiveness

As far as surgical treatment of the torn or insuf-
ficient CrCL is concerned, the other chapters
of this book have provided a more detailed
description. Briefly, the most commonly per-
formed procedures are tibial plateau leveling
osteotomy (TPLO), extracapsular repair using
Tightrope®(TR), and tibial tuberosity advance-
ment (TTA) osteotomy. Of note, none of these
procedures actually repairs or reconstructs the

ruptured ligament, and each of them is associ-

ated with a relatively high risk of subsequent

meniscal injury and OA (Slocum & Slocum

1993; Raywardet al. 2004; Lazaret al. 2005; Mor-

ganet al. 2010). A successfully repaired liga-

ment could potentially provide both dynamic

and passive stability, while preserving propri-

oception, and could potentially avoid some of

these longer-term complications. However, any

endeavor to stimulate CrCL healing starts with

the question of why the ligament fails to heal in

the first place.

Why cruciate ligaments do not heal

The fact that cruciate ligaments do not heal

has been baffling to both veterinarians and

physicians. This inability to heal is even more

surprising given that collateral ligaments

heal spontaneously with minimal treatment

(Franket al.1983a; Franket al.1983b; Hannafin

et al.1999). Cells from cruciate and collateral

ligaments have similar capabilities in terms

of proliferation, migration, and biosynthesis

(Murray & Spector 1999; Murrayet al.2000a;

Murrayet al.2000b; Murrayet al.2002; Mur-

rayet al.2007a). However, it was found that

cruciate injuries, as opposed to collateral

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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