Abstract 35

RELATIONSHIP BETWEEN WEAR AND PROGRESSION OF OSTEOLYSIS BASED ON CT, WEAR AND MIGRATION ANALYSIS

*Stamenkov R, Howie D, Taylor J, Findlay D, Kourlis G, McGee M, Neale S, Pannach S

*Dept. Orthopaedics & Trauma, Royal Adelaide Hospital, The University of Adelaide

Periprosthetic osteolysis remains a significant complication of total hip replacement (THR). Accurate data on the extent and progressive nature of osteolytic lesions is important for the planning of surgical intervention and for monitoring potential medical treatments. The aim of this study was to use quantitative CT, with wear and migration analysis, to determine the progression of osteolysis and to examine the relationship between wear and osteolysis. EBRA was first used to exclude cases with migrated components to avoid the potential confounding effects of migration on osteolysis measurement. Quantitative CT was used to measure the volume of periacetabular osteolytic lesions and the progression of osteolysis over 12 months. To date, 12 patients (median implant duration 15 years, range 13-16) have been monitored prospectively. Polyethylene wear was determined using Polyware.

Importantly, some osteolytic lesions were quiescent while others progressed markedly. The rate of progression of osteolytic lesions ranged from 0.01 to 10.1 cm³/12 months. The increase in osteolysis volume over 12 months correlated strongly with volumetric polyethylene wear rate (r=0.71, p=0.014). In hips with volumetric wear of less than 50mm³ /year, the progression of osteolysis was small.

This is the first reported evidence, using quantitative CT and radiographic analysis techniques, which shows differences in the progression of osteolysis with time. This provides important data for patient management. Using this technique, the relationship between the progression of osteolysis and polyethylene wear is more accurately defined. (228/250).

Return to Listing of 2004 Abstracts
View Listing of 2005 Abstracts