Page 92 - ASOP ROT Study Guide

of vitamins may affect bones and joints and these may be classified as metabolic disorders.

Degenerative disorders - this again is a group of conditions which may result in inflammations. However, in this
case it usually refers to joint conditions where the normal structure of the joint has been disturbed through
deterioration and wear. Osteoarthritis fits in general into this category, although often there may be a lot of
associated inflammation.

Trauma - this is when the musculoskeletal system has suffered damage from an outside physical agent.

Classifications of orthopedic conditions such as this one are of course, to some degree, a matter of opinion. In
order to avoid confusion in this module, I propose to present the conditions of the musculoskeletal system in 5
groupings which reflect their importance, i.e. how common they are:

♦ arthritis and other joint conditions
♦ back pain
♦ conditions of childhood
♦ common adult disorders
♦ common fractures

Of all the conditions treated by orthopedic surgeons, arthritis (joint pain) takes up most of our clinic and
operating theatre time. Arthritis occurs in all races all over the world but is most common in the elderly. It is
therefore important to understand this orthopedic condition above all others. In general terms it is a painful and
distressing disorder which has profound effects on the quality of life. There is no specific cure and all treatment
strategies are based around the relief of the symptoms: pain and stiffness.

2. OSTEOARTHRITIS

Osteoarthritis is a condition of pain and limitation of movement of joints associated with excessive wear of
articular cartilage resulting from a breakdown of the balance between the wear and repair processes in the joint.
It is more common with increasing age although it would be misleading to suggest that all osteoarthritis is an
inevitable accompaniment to old age.

2 . 1 Cause and Classification

It is convenient to classify osteoarthritis according to etiology (cause). The classification starts by grouping
patients into those whose arthritis has a known cause (secondary osteoarthritis) and those where the cause
remains unknown (primary osteoarthritis). It is important to appreciate that the vast majority of patients fall
into the latter category.

2 . 1 . 1 Primary Osteoarthritis

Despite much effort there remains little insight into the causes of this very common condition. In our previous
definition we took osteoarthritis to encompass a breakdown in the balance between wear and repair. In the
case of secondary osteoarthritis it is perhaps easy to argue that many cases reflect an increase in wear. So it
may be assumed that in primary osteoarthritis the problem may be on the repair side of the equation.

Many cases of osteoarthritis are secondary to abnormal mechanical stresses applied to a joint as a result of an
injury for example. Perhaps in retrospect therefore, it is possible to classify more and more cases as secondary
rather than primary. However we are still left after a rigorous review of cases with a vast majority where the
cause is obscure. If the cause was a disorder of body metabolism in general then all or most joints would be
affected. In fact, the causative factor must be specific to the affected joint as, normally in an individual, not all
joints are affected. There are a few cases within every clinician's experience which do appear to have
generalized arthritis but these are rare.