The incidence of acute and chronic conditions
of the tendo Achillis appear to be increasing. Causation is multifactorial
but the role of inherited genetic elements and the influence of
environmental factors altering gene expression are increasingly
being recognised. Certain individuals’ tendons carry specific variations
of genetic sequence that may make them more susceptible to injury.
Alterations in the structure or relative amounts of the components
of tendon and fine control of activity within the extracellular
matrix affect the response of the tendon to loading with failure
in certain cases. This review summarises present knowledge of the influence of
genetic patterns on the pathology of the tendo Achillis, with a
focus on the possible biological mechanisms by which genetic factors
are involved in the aetiology of tendon pathology. Finally, we assess
potential future developments with both the opportunities and risks
that they may carry. Cite this article:
Rotator cuff tears are among the most common and debilitating
upper extremity injuries. Chronic cuff tears result in atrophy and
an infiltration of fat into the muscle, a condition commonly referred
to as ‘fatty degeneration’. While stem cell therapies hold promise
for the treatment of cuff tears, a suitable immunodeficient animal
model that could be used to study human or other xenograft-based
therapies for the treatment of rotator cuff injuries had not previously
been identified. A full-thickness, massive supraspinatus and infraspinatus tear
was induced in adult T-cell deficient rats. We hypothesised that,
compared with controls, 28 days after inducing a tear we would observe
a decrease in muscle force production, an accumulation of type IIB
fibres, and an upregulation in the expression of genes involved
with muscle atrophy, fibrosis and inflammation.Objectives
Methods