[Arthritis following osteosynthesis of supra-/intercondylar femoral fractures]

Of 104 supra-/intercondylar femur fractures in adults (AO/ASIF Classification types A 1-3 and C 1-3), who were treated by open reduction and internal fixation from 1975 to 1985 59 fractures in 57 patients could be traced and reviewed clinically and radiographically after a mean follow-up period of 5 years and 7 months (range: 2-11 years). Among these, 47 knees/patients without preexisting knee-joint pathology were analyzed for the development of degenerative arthritis. The incidence for grade 2 and 3 changes in the femoropatellar compartment were 23% for supracondylar fractures (A type) and 62% for intercondylar lesions (C type). In the femorotibial compartment the incidence for supracondylar fractures was 38% and 23% for intercondylar fractures. In 93% of the patients the arthritic changes were radiographical findings, which did not cause relevant symptoms. The development of radiographical degenerative changes depends mainly on the type of the fracture; it is favoured by axial malalignment of more than 5 degrees of varus or valgus and local complications.