Page 23 - Canine Lameness

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Preface

Canine lameness is a common problem in clinical practice. While there is a plethora of equine
literature illuminating causes of equine lameness, few such resources are available in the canine
field. This is likely because of the greater emphasis on lameness in daily equine practice. However,
with the recent surge of canine sports and pet owners placing increasingly more emphasis on
maximizing their dogs’ happiness and activity, the field of canine orthopedics is changing – thus,
determining an accurate diagnosis and the prevention of orthopedic disease are playing a larger
role in canine practice. The goal of this textbook, therefore, is to address this gap in the literature
by providing a single resource of clinically relevant information for the veterinary health profes-
sional faced with canine lameness problems.
Within the orthopedic community, lameness is generally defined as an alteration of normal loco-
motion that may be due to pain (e.g. arthritis or fractures), mechanical dysfunction (e.g. muscle
contractures), or neurologic conditions (e.g. spinal cord compression from disc disease; Renberg
2001; Baxter and Stashak 2011). However, within the neurologic community, lameness is more
specifically defined as pain from compression of the nerve roots and meninges (Chapter 4; Dewey
et al. 2016). This “neurogenic lameness” and monoparesis (i.e. lower motor neuron disease of a
single limb) are the most common reason for confusion between orthopedic and neurologic dis-
ease. For the purpose of this book, the term lameness is applied in its broader meaning, unless
specified otherwise (i.e. Chapters 4, 16, 21).
This book is divided into two sections. Section 1 focuses on lameness evaluation, describing the
different types of exams (e.g. orthopedic and neurologic examination, etc.) that aid in localization of
a problem causing gait abnormalities (Part I) and the recommendations regarding specific diagnostic
procedures that aid in establishing a definitive diagnosis (Part II). Section 2 describes the most com-
mon reasons for lameness, organized by the anatomical regions of the distal limb (Part III), thoracic
(Part IV), and pelvic (Part V) areas including the major joints and surrounding areas. For ease of
identification these chapters are marked with colored tabs. This organization was chosen to provide
a resource that mimics the hypothetical clinical scenario where the examiner first identifies an
abnormality (e.g. pain or swelling) in a specific area and then develops a differential diagnosis list and
diagnostic plan based on that finding. Thus, each region chapter focuses on musculoskeletal diseases
of the specific area. The other two causes of lameness, namely oncologic and neurologic, are described
in the individual Chapters 16, 17 and 21, 22 for the thoracic and pelvic limb, respectively.
The emphasis of this text is to provide the necessary resources to establish a diagnosis for dogs
presenting with lameness, with a particular focus on physical exam and radiographic findings.
While neurologic conditions are included, the scope of the book is limited to conditions that can
be confused with lameness. For this reason, conditions that cause obvious neurologic abnormali-
ties in multiple limbs are only discussed to the degree that they apply as a differential diagnosis for
lameness. The reader is encouraged to consult other resources for further details on neurologic