Purpose: This study aims to evaluate the e ects of the Accolade I® TMZF® metaphyseal stem on the periprosthe c bone density at the level of the 7 Gruen zones and to de ne the evolu on of bone resorp on associated to the design of the stem. The periprosthe c bone remodeling data were collected with DXA scan. Therefore, this study also intends to predict, based upon the collected results, the long-term dura on and stability of the stem, as they are directly related to the periprosthe c bone resorp- on process. Methods: 25 pa ents (11 men and 14 women) were selected in this study in accordance with speci c inclusion and exclusion criteria. Pa ents under- went total hip replacement with Accolade I® TMZF® hip stem (average age of 66). They were all clinically evaluated based on Harris Hip Score and Womac Score, and preopera ve radiology examina ons were performed. Clinical, radiological and bone density evalua ons were performed on each pa ent within six months and at 12, 24 and 36 months a er surgery. Results: The results at 36 months show a sta s cally signi cant increase (p<0.001) of the HHS scores, from 64 during preopera ve phase to 93 at 36 months. No pa ents underwent secondary replacement surgery and no radiolucency was found during radiological assessments. The bone mineral density changes in the 7 Gruen zones seen with DXA scan showed a decrease of 2.9% only at the level of the calcar region (R7), a moderate increase at the level of R1, R2 and R3 and a sta s cally signi cant increase of BMD (p<0,05) at 24 and 36 months a er surgery at the level of R4 (+6.2%), R5 (+7.2%) and R6 (+8.15%). Conclusions: Our study revealed that the Accolade I® TMZF® uncemented stem is safe as far as periprosthe c bone resorp on is concerned, a er a middle-long term follow-up evalua on at 36 months, since it shows a de - nitely posi ve BMD evolu on at the level of all Gruen zones and especially at the level of the medial region (R5, R6). The only excep on where BMD results mildly decreased (from 1.03 to 1.00) is at the level of R7, most likely due to weight load increase at a lower level (R6) compared to pa ent’s physi- ological condi on. Therefore, the DXA scan shows evidence of weight load changes mainly on the medial metadiaphyseal aspect, which results to be a fundamental parameter of the long-term stem longevity
DENSITOMETRIC EVALUATION OF PERIPROSTHETIC BONE RESORPTION AFTER SURGICAL PLACEMENT OF ACCOLADE I TMZF HIP STEM AT 36 MONTHS
PARCHI, PAOLO DOMENICO;CIAPINI, GIANLUCA;CASTELLINI, IACOPO;MARCHETTI, STEFANO;LISANTI, MICHELE
2015-01-01
Abstract
Purpose: This study aims to evaluate the e ects of the Accolade I® TMZF® metaphyseal stem on the periprosthe c bone density at the level of the 7 Gruen zones and to de ne the evolu on of bone resorp on associated to the design of the stem. The periprosthe c bone remodeling data were collected with DXA scan. Therefore, this study also intends to predict, based upon the collected results, the long-term dura on and stability of the stem, as they are directly related to the periprosthe c bone resorp- on process. Methods: 25 pa ents (11 men and 14 women) were selected in this study in accordance with speci c inclusion and exclusion criteria. Pa ents under- went total hip replacement with Accolade I® TMZF® hip stem (average age of 66). They were all clinically evaluated based on Harris Hip Score and Womac Score, and preopera ve radiology examina ons were performed. Clinical, radiological and bone density evalua ons were performed on each pa ent within six months and at 12, 24 and 36 months a er surgery. Results: The results at 36 months show a sta s cally signi cant increase (p<0.001) of the HHS scores, from 64 during preopera ve phase to 93 at 36 months. No pa ents underwent secondary replacement surgery and no radiolucency was found during radiological assessments. The bone mineral density changes in the 7 Gruen zones seen with DXA scan showed a decrease of 2.9% only at the level of the calcar region (R7), a moderate increase at the level of R1, R2 and R3 and a sta s cally signi cant increase of BMD (p<0,05) at 24 and 36 months a er surgery at the level of R4 (+6.2%), R5 (+7.2%) and R6 (+8.15%). Conclusions: Our study revealed that the Accolade I® TMZF® uncemented stem is safe as far as periprosthe c bone resorp on is concerned, a er a middle-long term follow-up evalua on at 36 months, since it shows a de - nitely posi ve BMD evolu on at the level of all Gruen zones and especially at the level of the medial region (R5, R6). The only excep on where BMD results mildly decreased (from 1.03 to 1.00) is at the level of R7, most likely due to weight load increase at a lower level (R6) compared to pa ent’s physi- ological condi on. Therefore, the DXA scan shows evidence of weight load changes mainly on the medial metadiaphyseal aspect, which results to be a fundamental parameter of the long-term stem longevityI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
