BACKGROUND: Limb salvage surgery (LSS) is the preferred method for treatment of patients with sarcomas and to a greater extent also to patients with metastatic bone disease. The aim of the present study was to evaluate the adaptive remodeling of the periprosthetic cortical bone after insertion of a tumor prosthesis with cemented stem. METHODS: A prospective study of 21 patients (F/M = 12/9), mean age 55 years (range 15-81) with metastatic bone disease (n = 9), sarcomas (n = 8) or aggressive benign tumors (n = 4) who underwent bone resection due to a tumor, and reconstruction with a tumor-prosthesis (Zimmer® Segmental 130 mm straight fluted cemented stem with trabecular metal (TM) collars) in the proximal femur (n = 10), distal femur (n = 9) or proximal tibia (n = 2). Measurements of bone mineral density (BMD) (g/cm2) were done postoperatively and after 3, 6, and 12 months using dual-energy X-ray absorptiometry. BMD was measured in 4 regions of interest around the cemented stem and in one region of interest 1 cm proximal from the ankle joint of the affected limb and measurement of the contralateral ankle was used as reference. Repeated measures ANOVA and students paired t-test was used to evaluate BMD changes over time. RESULTS: At 1-year follow-up, BMD decreased compared to baseline in all four regions of interest with a statistically significant bone loss of 8-15%. The bone loss was most pronounced (14-15%) in the 2 regions of interest closest to the trabecular metal (TM) collar and lowest (8%) adjacent to the tip of the stem. CONCLUSION: After 1 year the decrease in bone mineral density of the ankle on the affected limb was 9% and the contralateral ankle was close to baseline, thus suggesting that the periprosthetic bone mineral density changes during follow-up, mainly are caused by stress shielding and immobilization. TRIAL REGISTRATION: The study was approved by the Scientific Ethical Committee of the Capital Region of Denmark (J. No. H-2-2014-105) and the Danish Data Protection Agency (J. No.: 2012-58-00004 ).
BACKGROUND: Limb salvage surgery (LSS) is the preferred method for treatment of patients with sarcomas and to a greater extent also to patients with metastatic bone disease. The aim of the present study was to evaluate the adaptive remodeling of the periprosthetic cortical bone after insertion of a tumor prosthesis with cemented stem. METHODS: A prospective study of 21 patients (F/M = 12/9), mean age 55 years (range 15-81) with metastatic bone disease (n = 9), sarcomas (n = 8) or aggressive benign tumors (n = 4) who underwent bone resection due to a tumor, and reconstruction with a tumor-prosthesis (Zimmer® Segmental 130 mm straight fluted cemented stem with trabecular metal (TM) collars) in the proximal femur (n = 10), distal femur (n = 9) or proximal tibia (n = 2). Measurements of bone mineral density (BMD) (g/cm2) were done postoperatively and after 3, 6, and 12 months using dual-energy X-ray absorptiometry. BMD was measured in 4 regions of interest around the cemented stem and in one region of interest 1 cm proximal from the ankle joint of the affected limb and measurement of the contralateral ankle was used as reference. Repeated measures ANOVA and students paired t-test was used to evaluate BMD changes over time. RESULTS: At 1-year follow-up, BMD decreased compared to baseline in all four regions of interest with a statistically significant bone loss of 8-15%. The bone loss was most pronounced (14-15%) in the 2 regions of interest closest to the trabecular metal (TM) collar and lowest (8%) adjacent to the tip of the stem. CONCLUSION: After 1 year the decrease in bone mineral density of the ankle on the affected limb was 9% and the contralateral ankle was close to baseline, thus suggesting that the periprosthetic bone mineral density changes during follow-up, mainly are caused by stress shielding and immobilization. TRIAL REGISTRATION: The study was approved by the Scientific Ethical Committee of the Capital Region of Denmark (J. No. H-2-2014-105) and the Danish Data Protection Agency (J. No.: 2012-58-00004 ).
Entities:
Keywords:
Bone mass density; Dual-energy X-ray absorptiometry; Stress shielding; Tumor prostheses
Authors: Henrik S G Bodén; Olof G Sköldenberg; Mats O F Salemyr; Hans-Jerker Lundberg; Per Y Adolphson Journal: Acta Orthop Date: 2006-12 Impact factor: 3.717
Authors: Petri K Venesmaa; Heikki P J Kröger; Jukka S Jurvelin; Hannu J A Miettinen; Olavi T Suomalainen; Esko M Alhava Journal: Acta Orthop Scand Date: 2003-02
Authors: Tarja A Soininvaara; Hannu J A Miettinen; Jukka S Jurvelin; Esko M Alhava; Heikki P J Kröger Journal: J Clin Densitom Date: 2004 Impact factor: 2.963