HSS Ultrasound of the Month Case 146

Clinical History 35 year old male with injury to the middle finger of the left hand while rock climbing.

Ultrasound of the Month – Case 146

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Ultrasound of the Month – Case 146

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Diagnosis: A2 Pulley Rupture The annular pulleys of the fingers are fibrous bands that hold the flexor tendons against the phalanges and provide a mechanical advantage to the flexor tendons.

Among the 5 annular pulleys, the A2 pulley, located at the level of the proximal phalanx, is the strongest.

A2 pulley injuries are common in rock climbers.

Both ultrasound and MRI are useful for diagnosing pulley injuries.

On ultrasound, disruption of the A2 pulley itself can be seen, but volar displacement of the flexor tendons away from the proximal phalanx, called “bowstringing”, is a secondary feature and is diagnostic.

Isolated disruption of the A2 pulley may be managed conservatively.

If conservative therapy is not successful, or if the A2 pulley disruption is accompanied by other injuries, surgical repair may be indicated.

Ultrasound of the Month – Case 146

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