Loss of proximal phalanx of thumb following a closed injury

LOSS OF PROXIMAL

PHALANX OF THUMB CLOSED INJURY

FOLLOWING

A

S. RATH and P. P. KOTWAL Department of Orthopaedics, All India Institute of Medical Sciences, New Delhi, India

We report a case of loss of the proximal phalanx of the thumb in a child following a closed dislocation of the inter-phalangeal joint and epiphyseal separation at the base of the proximal phalanx. Necrosis of the skin overlying the displaced bone converted a closed injury into a compound one. It is an unusual injury and no similar case has yet been reported in the literature. Case report An eight-year-old boy sustained a closed dislocation of the I.P. joint and total epiphyseal separation at the base of the proximal phalanx of the right thumb in a fall from bicycle. He was treated at a peripheral hospital by closed manipulation and a plaster-of-Paris cast. A week later, he was referred to our unit with a wound over the dorsum of thumb exposing the phalanx. The wound was infected. X-ray showed an unreduced dislocation of the I.P. joint and epiphyseal separation of the proximal phalanx (Fig. 1). At debridement, under general anaesthetic, the proximal phalanx was found to be devoid of soft tissue and surrounded by pus. During cleaning, the whole segment of proximal phalanx fell out: this was not replaced. The wound was debrided and length of the

Fig. 2 External fixator in position.

Fig. 1 Radiograph showing dislocation of the I.P. joint and epiphyseal separation at the base of the proximal phalanx.

thumb was maintained by an external fixator (Fig. 2). The wound healed under cover of antibiotics. Ten weeks later, the bone defect was filled with a cortico-cancellous graft from the ipsilateral ulna, maintaining the length of the thumb. The graft incorporated in eight weeks (Fig. 3) and six weeks later he had regained good pinch. Discussion Early reduction of severely displaced fractures and/or 378

Fig. 3

Radiograph showing incorporation of the bone graft.

dislocations is mandatory to prevent pressure necrosis of the overlying skin and subsequent problems such as occurred in the above case. Accepted 22 August 1990 Dr P. P. K&al, Associate Medical Science, New Delhi

Professor, Department 110 029, India

of Orthopaedics,

All India

Institute

6 1990 The British Society for Surgery of the Hand 02~7681/90/001~378/S10.00

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