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44 hips operated for insertion of the Christiansen hemiprosthesis at the County hospital of Nordland from 1968 to 1976 were evaluated in 1986. Seven hips had been reoperated because of loosening or mechanical failure of the prosthesis. Another four prostheses were found to have loosened at the time of follow-up, bringing the total loosening frequency up to 25 percent, 26 patients reported no pain from the hip, 20 of these were still in normal activity with no restriction in walking as a consequence of the defect hip. All the prostheses had been inserted in a varus position. Acetabular protrusion was found in 14 cases, indicating that there are frictional forces working at the hip joint, also with the trunnion bearing system. The average time from operation to verified loosening was nine years. The trunnion bearing may thus have spared the hip joint from stress during the first years of use.