Page 133 - ASOP ROT Study Guide

11. NERVE ENTRAPMENTS

All nerves are sensitive to compression and stretching. Such an injury is known as a "neuropraxia".
Continued pressure will lead to atrophy of the nerve which, at best, takes a very long time to recover
and usually is permanent (at least in part). Therefore early diagnosis and management is likely to give
the best results.

Nerve entrapments may be extrinsic to the body or intrinsic. Extrinsic causes include accidents where
consciousness is lost and the victim inadvertently presses on a nerve. Patients in bed or in plaster casts
are at risk from pressure on nerves in exposed sites. The most common site at risk is the common
peroneal nerve as it winds around the head of the fibula. Most cases are intrinsic, caused by structural
local anatomical variations or inflammatory swelling. Common sites are: the median nerve at the wrist,
the ulnar nerve at the elbow, the ulnar nerve at the wrist and the posterior tibial nerve at the ankle

11 . 1 Diagnosis

Any numbness or tingling in the area supplied by the nerve should be taken seriously. Weakness and
real sensory loss are diagnostic. If in doubt nerve conduction studies should be performed.

11 . 2 Management

Obvious causes such as bandage or cast must be removed. If symptoms persist then surgical relief of
pressure may be required. This involves cutting the skin and fascia.

12. TENOSYNOVITIS

Inflammation of tendons and their associated synovial sheaths is a common problem. It is often
associated with rheumatoid arthritis where it is part of a multi-system disease. In other situations it may
arise spontaneously, often with no known cause but usually it is precipitated by unusual levels of activity,
or overuse. It is an important condition to be aware of as it is often associated with worker
compensation and litigation

13. BURSITIS

Bursae are common structures around joints. A bursa is a small sac of fibrous tissue lined with synovial
membrane and filled with fluid. It acts as a natural form of "bearing" aimed at improving muscle and
joint function by reducing friction, usually where tendons and ligaments pass over bones. However, they
may also form in response to pressure. Bursae are prone to disorders resulting from repetitive movement
or strain, or from being subject to abnormal loads. Bursae around the shoulder are commonly affected
and these are dealt with in a separate section on shoulder discomfort. Commonest sites of bursitis
are around the knee and the elbow, and the greater trochanter at the hip may also be affected.

Those affected generally complain of chronic discomfort over the bursa, usually associated with the
causative element, such as movement or pressure. There may be swelling of the bursa, such as is seen
in housemaid's knee when the pre-patellar bursa swells.