1. Radiographic changes in bone structure which follow the insertion of an unplasticised acrylic prosthesis of the Judet type are described. 2. Technical details of the operation and their relation to these changes are discussed. 3. Although the period of observation is short it is suggested that after initial loosening the prosthesis becomes stabilised owing to local bone reaction.
1 . Complications of the Judet arthroplasty are few. 2. The antero-lateral approach provides good access to the joint for insertion of the prosthesis. 3. Details of treatment before and after operation are described and their importance in limiting complications is emphasised. 4. The complications that have been encounteredâincluding dislocation and fracture of the stemâare described and factors in their causation are discussed. 5. Study of the mechanical state of the new joint and the diagnosis of complications are aided by radio-opaque markers in the prosthesis.