Canine Sports Medicine and Rehabilitation, Second Edition. Edited by Chris Zink and Janet B. Van Dyke.
© 2018 John Wiley & Sons, Inc. Published 2018 by John Wiley & Sons, Inc.

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Musculoskeletal Structure

and Physiology

Summary

The musculoskeletal system consists of a diverse set of specialized tissues that define

overall body shape, and provide for coordinated movement. Structural integrity, health,

and appropriate functional conditioning of the musculoskeletal system are essential for

athletic performance. The response of musculoskeletal tissues to injury and disease,

disuse, or conditioning forms the basis upon which all athletic training and physical

rehabilitation programs are based. Effective sports medicine and rehabilitation practice

depends on an understanding of musculoskeletal tissue structure, physiological adapta-

tions to exercise, and maladaptive responses to injury and disease. This chapter pro-

vides an overview of key concepts in musculoskeletal tissue structure and physiology as

they pertain to athletic performance and recovery from injury. The molecular and histo-

logic structure, development, and functional properties of bone, cartilage, synovium,

tendon and ligament, and skeletal muscle are reviewed. Basic mechanisms underlying

injury and loss of function of musculoskeletal tissues as well as healing responses are

outlined. Emphasis is placed on structure–function relationships and physiological

concepts that are relevant to the performance and rehabilitation of the canine athlete.

Basic organization of musculoskeletal
connective tissues

With the exception of skeletal muscle, the tissues
that make up the musculoskeletal system are
generally classified as dense connective tissues.
Connective tissues are composed of tissue‐
specific mesenchymal cells distributed through­
out a specialized extracellular matrix (ECM).

Dense connective tissues consist predominantly

of ECM and contain relatively few cells.

The  ECM contains an array of structural fibers

made up of cross‐linked fibrillar proteins, along

with a hydrated gelatinous interfibrillar matrix

containing a variety of nonfibrillar proteins,

proteoglycans, glycoproteins, proteolipids,

and  polysaccharides. The composition and

molecular organization of the ECM define the

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Stuart Bliss, DVM, PhD, DACVS, CCRP