唑来膦酸对骨质疏松患者全髋关节置换术后假体周围骨密度的影响

目的：探讨注射用唑来膦酸5 mg对骨质疏松患者全髋关节置换术后假体周围骨密度的影响。方法选取2012年3月至2013年2月期间因骨质疏松性髋部骨折行全髋关节置换术的患者31例，所有患者初次诊断均为原发性骨质疏松症合并髋部骨折，入院前未曾行任何抗骨质疏松治疗，根据随机数字表分为两组：治疗组（16例，平均年龄73.8岁），全髋关节置换术后5～7 d给予唑来膦酸5 mg，静脉滴注30 min，同时口服钙尔奇600 mg/d及阿尔法D30.25 ug/d；对照组（15例，平均年龄74.1岁），术后仅给予口服钙尔奇600 mg/d及阿尔法D30.25 ug/d。分别于术后1周、3个月、6个月、12个月使用双能X线骨密度仪（ DEXA）测定两组患者假体周围各感兴趣区的骨密度值。结果两组患者术后3个月、6个月、12个月与术后1周（基线）股骨近端假体周围骨密度除Gruen1区外，2～7区骨密度均呈不同程度下降。治疗组与对照组骨密度变化值相比，术后3个月Gruen 4区（0.84％vs -3.34％， t＝3.5805）、7区（-3.61％vs -16.7， t＝4.0455）组间差异有统计学意义（P＜0.05）；术后6个月Gruen 1区（9.96％vs 1.17％， t＝2.1293）、4区（1.21 vs -2.96， t＝2.0892）、6区（-0.56 vs -6.16， t＝2.9500）、7区（-5.71 vs -22.8， t＝4.3959）组间差异有统计学意义（ P＜0.05）；术后12个月Gruen 1区（13.83 vs 1.39， t＝2.1795）、4区（0.81 vs -3.68， t＝2.1805）、6区（0.14 vs -6.04， t＝0.0247）、7区（-8.39 vs -25.4， t ＝3.8959）组间差异有统计学意义（ P＜0.05）。术后使用唑来膦酸3个月即表现出明显抑制骨量丢失的作用，并且于6个月、12个月时唑来膦酸对Gruen 1、4、6、7区骨量有持续的正向影响；Gruen 7个区中对1、7区的影响最大，治疗组1区骨密度增幅是对照组的9.95倍，7区骨密度减幅是对照组的1/3。结论唑来膦酸注射液5 mg能有效减少股骨假体周围骨密度的丢失，潜在的增加假体生物学稳定性，减少假体无菌性松动的概率，延长假体使用寿命。

Effects of zoledronic acid on bone mineral density around prosthesis after total hip replacement in osteoporotic patients

Objective To investigate the effects of zoledronic acid on the bone mineral density around the prosthesis in the patients with osteoporosis after total hip arthroplasty （ THA ） . Methods During March 2012 to February 2013, 31 patients in our hospital accepted total hip replacement surgery due to osteoporotic hip fractures .All the patients were initially diagnosed as primary osteoporosis combined hip fracture , with no anti-osteoporosis therapy before the admission. The patients were randomized into two groups based on a random number table：the treatment group （ n=16, mean age 73.8 years） were given zoledronic acid 5mg by intravenous infusion after THA for 5-7 days, combining oral Caltrate 600 mg/d and Alpha D3 0.25 ug/d;the control group （n=15, mean age 74.1 years） were given oral Caltrate 600 mg/d and Alpha D3 0.25 ug/d only.After one week, three months, six months, and 12 months, dual-energy X-ray absorptiometry （ DEXA ） was used to determine the bone mineral density around the prostheses of both groups .Results The bone mineral density around the proximal femoral protheses of Gruen zone 2-7 decreased in one week , three months , six months and 12 months after the surgery in varying degrees .Comparing the treatment group and the control group , the differences of the bone mineral density（BMD） in Gruen zone 4 （0.84% vs -3.34%,t=3.5805） and Gruen zone 7 （ -3.61% vs -16.7, t=4.0455） were statistically significant （P〈0.05） three months after the surgery;after 6 months, the differences of the BMD in Gruen zone 1 （9.96%vs 1.17%,t=2.1293）, zone 4 （1.21 vs -2.96, t=2.0892）, zone 6 （-0.56 vs -6.16, t=2.9500）, and zone 7 （ -5.71 vs -22.8, t=4.3959） were statistically significant （P〈0.05）;after 12 months, the differences of the BMD in Gruen zone 1 （13.83 vs 1.39, t=2.1795）, zone 4 （0.81 vs -3.68, t=2.1805）, zone 6 （0.14 vs -6.04, t=0.0247）, and zone 7 （-8.39 vs -25.4, t=3.8959） were statistically significant （P〈0.05）.Postoperative use of zoledronic acid for three months showed significant inhibition effects of bone loss , and it continued positively affecting the bone mass of Gruen zone 1, 4, 6 and 7 in 6 months and 12 months.The BMD in Gruen zone 1 of the treatment group was 9.95-fold higher than the control group; the BMD reduction in Gruen zone 7 was one third of the control group .Conclusions Zoledronic acid injection 5mg per day can effectively reduce the loss of the bone mass around the femoral prosthesis , potentially increase the biological stability of the prosthesis , and reduce the probability of the aseptic loosening , so as to prolong the life of the prosthesis .