anatomy and physiology mcqs

Question #132

A patient complaining of weakness and tingling in her right upper limb is diagnosed with a cervical rib. Which of the following signs is she most likely to have?

As the name suggests a cervical rib is one which arises at the level of the cervical vertebrae. It is seen in 1 in 200 people and most commonly arises at the level of C7. It results in narrowing of the thoracic outlet where the brachial plexus and axillary vessels run. This may cause compression of the lower trunk or the C8 and T1 nerve roots (in addition to the vascular symptoms).

The neurological symptoms will therefore result in numbness in the C8 and T1 dermatomes, and weakness in the muscles supplied by the ulnar nerve.

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