H. Hagino

Changing incidence of hip, distal radius, and proximal humerus fractures in Tottori Prefecture, Japan

A survey of all fractures in patients > or =35 years of age for hip, distal radius, and proximal humerus was performed in Tottori Prefecture, Japan. Hip fracture survey was done for the years 1986-1988, and also 1992-1994. A distal radius and proximal humerus fracture survey was done for the years 1986-1988, 1992, and 1995. The age- and gender-specific incidence rates of these three types of fracture among Japanese were substantially lower than those of whites living in North America or northern Europe. The age-adjusted incidence rates of hip fracture (per 100,000 person-years) were 40.7 and 114.1 in 1986 and 57.1 and 145.2 in 1994 for men and women, respectively, showing a significant increase with time for women. Upon examination of individual fracture types, there was no significant increase in cervical fractures, whereas a significant increase was observed in trochanteric fractures for women. The age-adjusted incidence rates of distal radius fractures for women were 164.9 in 1986 and 211.4 in 1995, showing a significant increase with time; however, no increase was observed among men. Incidence of proximal humerus fractures was 10.3 and 42.0 in 1986 and 17.1 and 47.9 in 1995 for men and women, respectively, and these increases were significant for both genders.

Cross-Sectional and Longitudinal Study of Osteoporosis in Patients with Rheumatoid Arthritis

Abstract: To elucidate the pathology of osteoporosis associated with rheumatoid arthritis (RA), bone mass measurements were performed in 146 female patients with RA and compared with those in 150 age-matched female patients with osteoarthritis (OA) and postmenopausal osteoporosis (OP). Bone mineral density (BMD) was measured at the lumbar spine (L-BMD), the mid-radius (MR-BMD) and the calcaneus (C-BMD) by dual-energy X-ray absorptiometry (DXA), and at the distal radius by peripheral quantitative computed tomography (pQCT). The RA group showed significantly lower BMD at all sites, except L-BMD, than the OA group. Compared with the OP group, the RA group showed a significantly higher L-BMD but no difference at other sites. BMD in RA decreased with disease severity at all sites and lean body mass was highly correlated with L-BMD and C-BMD. Cross-sectional analysis revealed early bone loss at the distal radius and a decrease of L-BMD, MR-BMD, and C-BMD with disease duration. Longitudinal analysis showed that the annual loss of L-BMD, MR-BMD and C-BMD tended to be lower with increasing disease duration. Glucocorticoid administration had no influence on L-BMD, MR-BMD or C-BMD. We concluded that, unlike postmenopausal osteoporosis, osteoporosis associated with RA is characterised by relatively preserved bone mass in the axial bone and marked loss in the peripheral bone. The risk factors for generalised osteoporosis are a long disease duration, severity of disease, and decreased lean body mass.

The incidence of fractures of the proximal femur and the distal radius in Tottori prefecture, Japan

SummaryWe report the incidence of proximal femur and distal radius fractures in Tottori prefecture, Japan. In 1986 and 1987, 573 proximal femoral fractures and 1576 distal radial fractures were registered in this district. The age- and sex-specific incidence rates of these two fractures are lower among Japanese than among European or North American whites, according to previous reports. Thus, it was concluded that the incidence rates of these two fractures are lower in Japanese than in Caucasians.

Effect of ED-71 on modeling of bone in distraction osteogenesis

We investigated the effect of 2-beta-(3-hydroxypropoxy)-1alpha,25-dihydroxyvitamin D3 (ED-71) on the modeling of bone in distraction osteogenesis. The tibiae of 30 rabbits were lengthened by 10 mm in 10 days. Following osteotomy, ED-71 (0.05 microg/kg) was administered subcutaneously twice a week to the ED-71 group until necropsy. The bone mineral content (BMC) of the lengthened callus was measured by dual-energy X-ray absorptiometry (DXA). Five rabbits per group were killed at 1, 3, and 8 weeks after completion of lengthening, and the lengthened callus was examined histologically and histomorphometrically. Bone volume of the lengthened callus was measured by peripheral quantitative computed tomography (pQCT) at 8 weeks after the completion of lengthening. At all timepoints the BMC in the ED-71 group was significantly higher than that in the untreated group. The mineral apposition rate and bone formation rate were higher in the ED-71 group than in the untreated group at 1 and 3 weeks after the completion of lengthening on the coronal section. In cross sections, the cortical area and width in the ED-71 group showed significantly higher values than in the untreated group at 8 weeks after the completion of lengthening. Both the endosteal osteoid surface and endosteal eroded surface showed no differences between groups. However, the endosteal mineral apposition rate and endosteal bone formation rate were significantly higher in the ED-71 group. At 8 weeks after completion of lengthening, the intracortical area and intracortical BMC were significantly greater in the ED-71 group than in the untreated group, but no significant difference was noted in intracortical BMD. These findings indicate that ED-71 increases callus volume during the early period after the completion of lengthening, resulting in thick cortical bone formation.

Bone Responses at Various Skeletal Sites to Human Parathyroid Hormone in Ovariectomized Rats: Effects of Long-term Administration, Withdrawal, and Readministration

This study was undertaken to examine bone responses to human parathyroid hormone (hPTH) at various skeletal sites. Forty 6-month-old female Wistar rats were divided into four groups, and bilateral ovariectomy (ovx) was performed in three of the four groups (n=30). The other group (n=10) received sham surgery (sham). Four weeks after the ovx, hPTH(1-34) administration was started. The ovx rats received 5 microg/kg per day of PTH (PTH-5; n=10), 10 microg/kg per day of PTH (PTH-10; n=10), or vehicle (PTH-v; n=10), three times a week for 24 weeks. Thereafter, PTH was withdrawn for 16 weeks followed by readministration at the same dosage for 8 weeks. The bone mineral content (BMC) at the whole skeleton and the bone mineral density (BMD) at the lumbar vertebrae, caudal vertebrae, distal femur, diaphysis of the femur, proximal tibia, and skull were longitudinally measured by dual-energy x-ray absorptiometry (DXA) at 4-week intervals during the experimental period. Thirteen rats that died during the experimental period were excluded from the analysis. As a result, the whole skeleton showed an increase in BMC during the PTH administration, whereas no withdrawal or readministration effects were observed. The metaphysis showed a highly sensitive bone response, while the lumbar vertebrae and diaphysis showed a moderate magnitude of changes in bone mass during the PTH administration. The skull and the caudal vertebrae did not show sensitive responses to PTH. After withdrawal, the BMD was markedly decreased at the sites that showed marked increases in BMD after PTH administration. The PTH readministration increased the BMD again at the sites that showed sensitive responses after the initial administration. Strength tests were also performed when the readministration was completed. The ultimate loads for the femur and vertebral body in the PTH-treated groups were significantly higher than those in the vehicle-treated group. In conclusion, the response to PTH in ovx rats varied among skeletal sites; withdrawal-related decreases were marked at the sites showing marked increases in bone mass related to PTH administration, and PTH readministration may be sufficiently effective.

Clinicoradiologic study of cervical laminoplasty with posterolateral fusion or bone graft.

Study Design. A retrospective study of cervical expansive laminoplasty for cervical myelopathy from a clinicoradiologic perspective. Objective. To clarify the correlation among sagittal curvature of the cervical spine, cervical range of motion, sagittal plane translation, spinal cord atrophy, and myelopathic symptoms in patients who have undergone laminoplasty. Summary of Background Data. Laminoplasties were developed to diminish the undesirable effects of laminectomy, which include postoperative kyphotic changes and instability. However, the superiority of laminoplasty over laminectomy remains controversial. Methods. Fifty-one patients with cervical spondylotic myelopathy or ossification of the cervical posterior longitudinal ligament who underwent laminoplasty were radiologically assessed before and after surgery. The index of the sagittal curvature, intervertebral range of motion, listhesis, and the transverse area of the spinal cord at the site of maximal compression were measured to evaluate interrelations among those parameters and myelopathic symptoms. Results. There were no patients with kyphotic curvature before surgery. The postoperative curvature tended to be less lordotic. This tendency did not adversely affect postoperative symptoms. The intervertebral range of motion was significantly decreased except at C1–C2. The final C4–C5 range of motion and the postoperative myelopathic symptoms were negatively correlated. A significant correlation was observed between the postoperative spinal cord atrophy and the final myelopathic symptoms. Conclusions. The decrease in the lordotic curvature index and the decrease in the intervertebral range of motion after laminoplasty did not cause neurologic deterioration. In the C4–C5 intervertebral segment with a high incidence of listhesis, the restriction of the C4–C5 range of motion improved the clinical myelopathic symptoms. The radiologic prognostic factors were the postoperative restriction of intervertebral range of motion in preoperatively unstable segments and the anatomic reversibility of spinal cord insult.

Measurement of human trabecular bone by novel ultrasonic bone densitometry based on fast and slow waves

SummaryTwo longitudinal transmitted waves, fast and slow waves, were observed by employing a new quantitative ultrasound (QUS) method. The trabecular bone measurements generated by this method reflect three-dimensional structural information, and the new QUS parameters were able to identify vertebral fractures.IntroductionThe aims were to identify new quantitative ultrasound (QUS) parameters that based on new QUS method reflecting not only bone volume but also the microstructures of trabecular bone ex vivo and to observe how much they predict fracture risk in vivo.MethodsEx vivo measurement: Three human femoral heads were used for the experiment. Attenuation of the slow wave, attenuation of the fast wave, speed of the slow wave, speed of the fast wave (SOFW), bone mass density of trabecular bone, and elastic modulus of the trabecular bone (EMTb) of each specimen were obtained using a new QUS method and compared with three-dimensional structural parameters measured by micro-computed tomography. In vivo measurement: Eighty-nine volunteers were enrolled, and the bone status in the distal radius was measured using a new QUS method. These parameters were compared with data evaluated by peripheral quantitative computed tomography and dual X-ray absorptiometry.ResultsEx vivo measurement: SOFW and EMTb showed correlations with the parameter of trabecular anisotropy. In vivo measurement: The new QUS parameters were able to identify vertebral fractures.ConclusionThe newly developed QUS technique reflects the three-dimensional structure and is a promising method to evaluate fracture risk.

Case-control study of risk factors for fractures of the distal radius and proximal humerus among the Japanese population.

We conducted a case-control study to identify risk factors for fractures of the distal radius and proximal humerus. Subjects were selected from women aged 45 and over with distal radius and proximal humerus fractures, resulting from minor trauma. Two age- and gender-matched controls for each case were selected from patients who subsequently visited the same clinic for treatment of conditions other than fractures. Questionnaires including anthropometric data, past and current physical activity, and lifestyle were sent by mail to both subjects and controls. A total of 140 women with distal radius fractures (mean age 67.4 years) and 242 controls were analyzed. Falls during the previous year were a significant risk factor, while futon use (instead of bed use) before fracture was a protective factor for distal radius fractures. A total of 37 women with proximal humerus fractures (mean age 76.3 years) and 67 controls were analyzed. Weight loss was a significant risk factor, while greater frequency of going outside significantly decreased the risk of proximal humerus fracture. There was no significant correlation with eating habits, milk and alcohol consumption, or smoking to the risk of either fracture.

Fracture incidence and bone mineral density of the distal radius in Japanese children

SummaryThe incidence of fractures of the distal radius in Japanese persons under 20 years of age was determined, and the bone mineral density of the radius was measured in 236 healthy Japanese children. The peak incidence of fractures occurred at 13 years of age (807 per 100000) in boys and at 11(300 per 100000) in girls. Bone mineral density increased with age, but the rate of increase was not equal at the metaphysis and the diaphysis in the parapubertal period. The metaphyseal/diaphyseal ratio of bone mineral density was lowest at the age of 12–13 years in boys and 11 years in girls. The age at the peak incidence of fractures thus coincided with the age at which the metaphyseal/diaphyseal density ratio was lowest. Thus, it is suggested that low bone mineral density at the metaphysis may be the cause of the high incidence of these fractures in adolescence.

Risk factors for hip fracture in elderly Japanese women in Tottori Prefecture, Japan

Many epidemiological surveys have been done in Europe and the United States on the incidence of hip fracture and the effects of lifestyle on fracture rate. We carried out a similar investigation during the 3-year period from 1986 to 1988 in Tottori Prefecture, Japan. This prefecture which had a population of 616 399 in 1986, is a typical retirement district, located in the mid-western part of the main island on the coast of the Sea of Japan. We studied the incidence of osteoporotic limb fractures, especially hip fractures, in this district and recorded for each fracture its cause, location of the accident, probable risk factors in the patients lifestyle, and its effect on the patients activities of daily living (ADL) after repair. Incidence of Osteoporotic Fractures