[Pseudarthrosis of the lower end of the radius due to interposition of the long extensor of the thumb].

The authors describe one case of a severely displaced Smith's fracture which was originally immobilised by external fixation. Three month's later the fracture had not united and active extension of the thumb was absent. At operation, the extensor pollicis longus tendon was found to be dislocated into the fracture site. The tendon was repaired and the non-union was treated by plating. A review of the literature discovered only one other similar case.