The fixation of porous-coated femoral stems. A radiographic study of 113 cases with a 4 to 8 year follow up.

Changes occurring in the fixation of 113 porous-coated PCA uncemented femoral stems were studied in 90 patients who were operated on between 1984 and 1988. The average follow up was 5 years. Fixation was classified in radiographs as osteointegration, stable fibrous fixation or unstable. Four femoral components were revised. Metaphyseal osteoporosis was associated with those with a stem diameter greater than 13 mm. After 2 years, osteointegration was present in 73% and instability in 24% which was not related to the position of the stem. At the end of the follow up period, 20% of the stems showing osteointegration had changed and become unstable.