Although entrapment of the extensor pollicis longus tendon in association with a Smith’s fracture has been reported previously, a search of the literature has failed to reveal a case in which all the extensor tendons have been entrapped. We describe such a case, the entrapment only being recognised at operation. Pre-operative diagnosis would have eased the surgical procedure considerably. Case report. A 13-year-old girl fell from her bicycle suffering a Salter type II Smith’s fracture of the left radius with an associated fracture of the ulna (Figs 1 and 2). She was unable to extend her fingers actively but it was assumed that this was due to pain from the fracture. A closed manipulation was performed but check radiographs showed that a satisfactory reduction had not been achieved. A further manipulation also failed and the fracture was therefore exposed through a ventral incision, reduced and fixed with K-wires. A radiograph taken in the operating theatre again showed failure of reduction. A dorsal incision was then made to exclude soft tissue interposition. The extensor retinaculum was found to be disrupted and the extensor tendons had passed through the torn interosseus membrane from the dorsal to the ventral aspect of the wrist at the level of the fracture. The tendons were freed and the fracture fixed with two cortical screws. The patient subsequently made an uncomplicated recovery. Discussion. In two of the three reported cases of entrapment of the extensor pollicis longus tendon in association with a fracture of the distal radius the diagnosis was only made some weeks after the injury when the patients returned with inability to extend the flexed thumb (Hunt 1969; Murakami and Todani 1981; Morrissey and Nalebuff 1977). There was similar delay in our case.
