The Trabecular Heterogeneity Of Femoral Head In Male Osteoporotic Fracture

Objective:The aim of this study was to investigate the femoral head trabecular heterogeneity in Chinese male patients with osteoporotic fracture and their effects on osteoporotic fracture.Methods:Human femoral heads were obtained from 11 male osteoporotic fracture(OP) patients(average age 65.17±9.00 years old, ranged from 51 to 82 years old),and 8 male trauma(TM) patients (average age 60.86±11.40 years old,ranged from 46 to 75 years old) who underwent total hip arthroplasty in two hours for either osteoporotic or trauma hip fracture.The OP was defined as having a fragility fracture. After laying femoral head as living body position and locating mark,nine trabecular specimens were obtained from which were orientated along the vertical plane of the primary compressive in the maximum diameter of femoral heads,each of 6×6×7mm³.The cortical shell was not included in each specimen.The cube which is in the middle of the femoral head was selected as the primary compressive trabecular region and the other 8 specimens as non-primary compressive trabecular region.These cubes were scanned using high-resolution microcomputed tomography scanner (μCT).After canning,the data of total cubes,primary compressive trabecular region and non-compressive trabecular region were used for analysis.Results:In OP than in TM throughout the femoral head apparent BMD(vBMD)(186.80±67.74 VS 247.09±121.89 mg/mm³),tissue BMD(tBMD)(543.34±65.44 VS 569.56±97.58 mg/mm³),bone volume fraction(TV/BV)(0.2252±0.0598 VS 0.2783±0.1120%),trabecular thickness(Tb.Th.)(166.00±49.09 VS 199.14±92.36μm),trabecular number(Tb.N.)(1.4662±0.2342 VS 1.5734±0.2884 #/mm³) were significantly decreased while bone area density(BS/BV)(13.58±2.60 VS 12.75±4.08 mm^-1),trabecular separation(Tb.Sp.)(781.52±150.68 VS 651.59±115.58μm),degree of nisotropy(DA)(1.5645±0.2074 VS 1.4684±0.1793) were significantly increased(P＜0.05).No significant differences were found in the structure model index(SMI),Connectivity density(Conn.D).Trabecular thickness(Tb.Th.)(199.37±68.22 VS 176.33±71.21μm ) were significantly increased in the primary compressive trabecular region than that in the non-primary compressive trabecular region and no significant differences were found in the other parameters in the all 18 specimens.In OP group vBMD(223.97±70.92 VS 182.15±66.00 mg/mm³),tBMD(580.01±63.86 VS 538.76±64.72 mg/mm³),TV/BV(0.2565±0.0708 VS 0.2212±0.0574%),Tb.Th. (205.47±74.44 VS 161.07±42.75μm) were significantly increased while BS/BV(12.28±2.70 VS 13.75±2.55 mm^-1) was significantly decreased in the primary compressive trabecular region than that in the non-primaty compressive trabecular region(P＜0.05).No significant differences were found in Tb.N.,Tb.Sp.,SMI,Conn.D and DA.No significant differences were found between the two regions for any of the parameters measured in TM.vBMD(182.15±66.00 VS 248.05±126.53 mg/mm³),tBMD (538.76±64.72 VS 570.54±100.32 mg/mm³),TV/BV(0.2212±0.0574 VS 0.2791±0.1163%),Tb.Th.(161.07±42.75 VS 200.31±96.63μm),Tb.N. (1.4614±0.2270 VS 1.5720±0.2945 #/mm³) were significantly decreased while Tb.Sp.(780.82±144.85 VS 653.09±119.64μm),DA (1.5674±0.1967 VS 1.4719±0.1808) were significantly increased in OP than in TM.in the non-compressive trabecular region.No significant differents were found between OP and TM for any of the parameters measured in the primary compressive trabecular region.Conclusions:The femoral head trabeculae had a heterogenic distribution in OP.Bone loss in OP primarily takes place in non-compressive trabecular region.Femoral neck fracture cannot be prevented though the bone microstructure do not loss in the primary compressive trabecular region.Tb.Th.in the femoral head could be an interesting parameter which is closely related to the femoral neck fracture.