Vaughan-Jackson-like syndrome as an unusual presentation of Kienb？ck's disease: a case report

A 40-year-old man of Indian ethnic origin with no known history of trauma presented to our clinic with a ten-day history of an inability to extend his right little and ring fingers with associated pain in his right wrist. He was being treated with long-term steroids but had no other significant medical history. His examination revealed an inability to extend the metacarpal and phalangeal joints of the right ring and little fingers with localized tenderness over the lunate bone. Spontaneous disruption of the extensor tendons was diagnosed clinically and, after radiological investigation, was confirmed to be secondary to dorsal extrusion of the fragmented lunate bone. The patient underwent surgical repair of the tendons and had a full recovery afterward.Kienb？ck's disease, though rare, is an important cause of spontaneous extensor tendon rupture. The original description of Vaughan-Jackson syndrome was of rupture of the extensor tendons of the little and ring fingers caused by attrition at an arthritic inferior radioulnar joint. We describe a case of a patient with Kienb？ck's disease that first appeared to be a Vaughan-Jackson-like syndrome.Kienb？ck's disease is a condition of uncertain etiology that results in osteonecrosis of the carpal lunate bone. Patients with this disease present with reports of activity-related dorsal wrist pain, decreased wrist motion in the flexion-extension arc, and poor grip strength. The symptoms tend to occur more often in the dominant hand.Vaughan-Jackson syndrome is characterized by the disruption of the digital extensor tendons, beginning on the ulnar side with the extensor digiti minimi (EDM) and extensor digitorum communis (EDC) tendon of the small finger. If the underlying pathology is not treated, sequential rupture of the ring, long, and index finger EDC tendons occurs [1]; ultimately, rupture of the extensor indicis proprius may follow [2]. Vaughan-Jackson's first report [1] of extensor tendon rupture described the cases of two e