Abstract
Interestingly, recent studies have shown promising outcomes in elderly. To the best of our knowledge there are no reports available assessing sequential bone remodelling around DCPD (dicalcium phosphate dehydrate) coated short metaphyseal loading stem using serial radiography. Hence we report the unique patterns of bone remodelling in patients 70 years and older and whether these patterns were different from those seen in younger patients.
A total of 41 consecutive primary hip arthroplasties were performed in patients with averaged age of 78.3 years using short stem. The presence and patterns of radiolucent lines, radio-opaque lines, calcar rounding, proximal bone resorption, spot welds, cortical hypertrophy, and intramedullary bone formation around the distal tip were assessed at serial radiography up to averaged follow up of 24.5 months.
In early stage of stability, the radio-opaque line appeared in lateral aspect of stem which might means the tension force of stem. On the contrary to this findings, the medial side of stem mainly showed the spot welds due to compression on calcar support.
The sequential radiographic bone remodelling in 70 years and older showed the different pattern from those of 30 to 50 year-old. Formation of new endosteal trabeculation (spot welds) were seen only in 55.6% of stems among the elderly study group where as all patients showed spot welds in the younger group. Calcar resorption was often observed in younger group but the degree of calcar resorption was less. The other findings in elderly patients was not different compared to those of younger patients.
