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INSTRUCTION

Look at this patient's back.

SALIENT FEATURES

History

· Difficulty in raising the arms above the level of the shoulders.· Winging of the scapula.

Examination

· Winging of the scapula.· Difficulty in raising the arms above the horizontal.Proceed as follows:· Check whether the winging is unilateral or bilateral.- Ask the patient to push the outstretched arm firmly against your hand, and check whether or not the winging is more prominent.· Tell the examiner that you would like to examine the muscles in the arm to rule out muscular dystrophy.

DIAGNOSIS

This patient has winging of the scapula (lesion) due to palsy of the long thoracic nerve of Bell (aetiology).

ADVANCED-LEVEL QUESTIONS

Which nerve lesion is responsible for these signs?

Long thoracic nerve of Bell arising from the anterior rami of C5, C6 and C7.

Which muscle is supplied by this nerve?

Serratus anterior.

What is the action of the serratus anterior?

It is responsible for the lateral and forward movement of the scapula, keeping it closely applied to the thorax.

Which other muscle palsy can cause winging of the scapula?

Paralysis of' the trapezius.

How would you differentiate winging of the scapula caused by serratus anterior palsy from that of trapezius palsy?

In serratus anterior palsy, abduction of the arm laterally produces little winging of the scapula, whereas winging due to weakness ofthe trapezius is intensified by abduction of the arm against resistance

.What do you know about brachial neuritis?

Brachial neuritis (neuralgic amyotrophy, Parsonage-Turner syndrome) often follows an infection or surgery. Diagnosis may bedifficult initially when the patient has only pain. Later the patient has muscular weakness, affecting particularly the deltoid andserratus anterior (winging of the scapula). Atrophy often becomes prominent. In this syndrome there is often more than one lesion.The white cell count in the cerebro-spinal fluid is occasionally raised. Recovery occurs over the next year and may not be complete.