Application of left femoral neck radioactive uptake ratio in (99)Tcm-MDP bone scan for evaluation of osteoporosis

Abstract

Objective To evaluate the value of 99Tcm-MDP uptake by left femoral neck for diagnosing osteopomsis.Methods A total of 58 cases (23 males,35 females,mean age:(66.15±8.45) years) with spondyloarthmpathies from May to December of 2012 were selected.Serum concentrations of type Ⅰ collagen telopeptide (sCTX-1) and bone ALP (BALP) were determined.All patients underwent dual-energy X-ray absorptiometry (DXA) to detect bone mineral density (BMD).According to the T scores,patients were divided into 2 groups:normal group (NG) (T＞-1.0) and osteoporosis group (OG) (T≤-2.5).99TcmMDP bone scan was further performed.The average radioactive ratio of the left femoral neck to the medial soft tissue of left femur (T/N) was measured.Data differences between the 2 groups were compared by twosample t test and Pearson correlation analysis.Results According to BMD,13 patients (7 males,6 females) were included in NG and 28 patients (10 males,18 females) were included in OG.The mean ages of OG and NG were significantly different ((68.82± 10.41) years vs (62.46± 11.77) years; t =3.560,P＜0.05).The BMD of left femoral neck in OG was significantly lower than that in NG ((0.67±0.08) g/cm2 vs (0.91±0.10) g/cm2 ; t=9.917,P＜0.01).Although BALP level of OG was significantly higher than that of NG ((35.92±11.58) U/L vs (22.38±6.34) U/L; t=-3.397,P＜0.05),no significant difference was observed on sCTX-1 between the 2 groups (t=-0.463,P＞0.05).T/N ratio of OG (11.63±6.22) was higher than that of NG (9.74±4.44) (t =-3.027,P＜ 0.05).There were significant correlations between the T/N ratio of the left femoral neck and the sCTX-1 and BALP concentrations (r=0.376,0.483,both P＜0.01).No correlations between the T/N ratio of the left femoral neck and age,BMI and BMD were observed (r=-2.031,-0.017,0.134,all P＞0.05).Conclusion The uptake ratio of the left femoral neck in 99Tcm-MDP bone scan could evaluate the metabolism of bone,and it is useful for the early diagnosis of osteoporosis. Key words: Osteoporosis ; Radionuclide imaging; MDP