Das Einwachsverhalten von Knieendoprothesen bei Arthrosepatienten: Früherkennung periprothetischer Umbauprozesse mittels Dualer Röntgenabsorptiometrie

Abstract

Bone remodelling after knee arthroplasty often is characterized by a loss of mineral density. Objective of the present study was to investigate periprosthetic bone loss by the use of DXA for assessment of bone mineral density. The present investigation concerned 12 patients (average age 70.5 years) with primary knee joint replacement due to osteoarthrosis. The contralateral knee had not been replaced in any of the patients. Anteroposterior and lateral DXA-shots of the femur, the tibia and the total knee (both sides) were taken two weeks, three and nine months after operation. The comparison of bone mineral density (BMD) after knee arthroplasty disclosed a conspicuous decline of bone density within nine months. Bone mineral loss amounted to an average of 9% in ap- and 18% in lateral findings. Especially lateral femur shots showed an average decrease of 21 % of density. However, the contralateral knees did not reveal significant BMD-changes. The results of the present investigation show that DXA, especially lateral shots of the femur, can be recommended for early assessment of periprosthetic bone loss in patients with knee arthroplasty.