The two to five-year clinical results of 200 Tharies surface
replacements were comparable to those of conventional total hip
replacement. The incidence of systemic complications, dislocations, and
sepsis was low. There were ten cases of aseptic and one case of septic
loosening. Nine minor secondary procedures were required in the series. In
two patients the femoral component shifted asymptomatically into varus
angulation, but no revision was needed. Fifty-five per cent of patients for
whom serial radiographs were available had some progression of
radiolucency, but there was poor correlation between the width of the zone
and loosening until the patient became symptomatic. Improved techniques of
preparation of the interface and of delivery, compression, and containment
of the cement have improved the postoperative radiographic appearance of
the more recently treated patients.