Densitometric evaluation of periprosthetic bone remodeling

Abstract

The application of Dual-energy X-ray absorptiometry (DEXA) in orthopaedic surgery gradually has been extended from the study of osteoporosis to different areas of interest like the study of the relation between bone and prosthetic implants. Aim of this review is to analyze changes that occur in periprosthetic bone after the implantation of a total hip arthroplasty (THA) or a total knee arthroplasty (TKA). In THA the pattern of adaptive bone remodeling with different cementless femoral stems varies and it appears to be strictly related to the design and more specifically to where the femoral stem is fixed on bone. Short stems with metaphyseal fixation allow the maintenance of a more physiologic load transfer to the proximal femur decreasing the entity of bone loss. Femoral bone loss after TKA seems to be related to the stress shielding induced by the implants while tibial bone remodeling seems to be related to postoperative changes in knee alignment (varus/valgus) and consequently in tibial load transfer. After both THA and TKA stress shielding seems to be an inevitable phenomenon that occurs mainly in the first year after surgery.KEY WORDS: dual-energy X-ray absorptiometry; adaptive bone remodeling; total hip arthroplasty; total knee arthroplasty.Stem. Remodeling patterns around a femoral stem are affected by several factors. These include patient-related factors, such as gender, age, initial femoral bone stock, patient activity, and underlying-disease as well as prosthesis-related factors, such as the type of fixation, stem length, stiffness, design, the extent of the coating area, and the method of

Densitometric evaluation of bone remodelling around Trabecular Metal Primary stem: a 24-month follow-up

“…At the present time, DEXA is considered the most reliable tool for evaluating pre-existing bone quality in order to plan correctly surgical procedure and study bone remodelling after THA as it is more sensitive and precise than conventional X-rays [20,21]. Analysis of seven periprosthetic Gruen zones is the most commonly used protocol for evaluating bone remodelling after the implantation of conventional femoral stems.…”

Periprosthetic bone remodeling of short cementless femoral stems in primary total hip arthroplasty

“…[ 15 ] Similar findings were reported by a previous review which summarized the pattern of periprosthetic bone remodeling that short stems with metaphyseal fixation in SHA allowed a decrease of bone loss in proximal femur compared with THA. [ 33 ] However, these results lack a randomization or direct comparison between SHA and THA which may reduce the power of comparability.…”

Migration of the femoral component and clinical outcomes after total knee replacement: a narrative review

“…Indeed, DEXA analysis could be used also in the assessment of bone remodeling of the femoral condyles after TKR [7]. Three studies show a dominating tendency toward decrease in tibia and femur bone mineral density (BMD) after the implantation of TKR [7][8][9][10][11][12][13][14][15][16][17][18][19]. However, BMD was shown to be an effective tool only in some specific loading conditions, as stated in a preclinical cadaveric study [20].…”