HSS Ultrasound Case 67

Clinical History 42 year-old woman with numbness in the left fourth and fifth fingers.

The patient was referred for an ultrasound (US) of the elbow to assess for ulnar nerve pathology.

Ultrasound of the Month – Case 67

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Ultrasound of the Month – Case 67

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Ultrasound of the Month – Case 67

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Diagnosis Anconeus epitrochlearis muscle (accessory anconeus muscle)

Discussion The anconeus epitrochlearis is an accessory muscle which originates from the olecranon and inserts on the medial epicondyle This accessory muscle at the elbow may be asymptomatic but has been implicated as a cause of cubital tunnel syndrome which leads to ulnar neuritis The anconeus epitrochlearis may be unilateral or bilateral The anconeus epitrochlearis, also known as the accessory anconeus, is not to be confused with the anconeus muscle which is found at the lateral aspect of the elbow

Ultrasound of the Month – Case 67

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