Search

This cross-sectional study was done in order to ascertain whether there is a lifelong beneficial effect on bone mineral density (BMD) of early, long-lasting, and intense physical exercise. Forty-eight male ex-weight lifters, mean age 64 years (range 50–79) participated. They had followed a training program of an average of 10 hours/week (range 4–20) for an average of 13 years (range 1–34). They had all retired from competitive sport an average of 30 years (range 7–50) ago. Sixty-six age-matched volunteers served as controls. The bone mineral density (BMD, areal density, g/cm2) in the total body, spine, and hips and the fat content and lean body mass were measured with the LUNAR DPX bone mass scanner. In ex-weight lifters 50–64 years of age, the BMD was greater than in controls. After 65 years, no difference was found between the former weight lifters and their controls.

Thirty-six women aged 60, 70 or 80 years who had fractured one of their distal radii (Colles' fracture) 0 to 35 (median 10) years earlier were examined in this population-based study. Single photon measurements (SPA) were performed on both arms 1 cm and 6 cm proximal to the styloid process of the ulna. All women were questioned about earlier wrist fractures and which, if any, side had been affected. Information about the type and site of the fracture was also gathered from the hospital records. The bone mineral content (BMC) was found to be increased by almost 20% in the once-fractured radius at the distal measuring site (1 cm) when compared with the unaffected side. This difference did not seem to diminish with time. At the proximal measuring site there was no difference between the once-fractured and the non-fractured side. There was a progressive loss of bone mineral in the once-fractured arm during the first years after the fracture however. This appeared to be reversed after about 10 years to a relative gain, even though the correlation was weak. Six of the 36 women could not remember which side had been fractured and five could not remember having had such a fracture at all. Determination of osteoporosis by measuring forearm BMC with single photon densitometry is therefore of limited value in some women of the oldest age groups.

Summary During a 13 year period, 286 patients with cervical disc herniation and/or spondylotic spurs, were subjected to anterior decompression and vertebral interbody fusion with autologous bone.

Abstract.: Bone mineral density (BMD) was measured in the upper part of the skull, the femoral neck, and the total body by dual energy X-ray absorptiometry in 56 male and 33 female active athletes, 18–40 years of age, together with 64 male ex-weight lifters, 35–79 years of age. The active athletes were compared with 41 male and 54 female controls, the ex-weight lifters with 133 male controls. The purpose of the study was to see if BMD in the upper part of the skull, a region virtually unaffected by physical load, is different in athletes and controls. The male athletes had a 3% higher BMD for the total body and 12% for the hip, whereas the BMD for the upper part of the skull was 10% lower than controls. Corresponding BMD values for the female athletes were 4% higher for total body and 10% for the femoral neck, and the upper part of the skull was 7% lower than in controls. After 65 years of age there was no difference in BMD comparing ex-weightlifters and controls. Using a constructed ratio BMD total body to BMD upper part of the skull, the ex-weight lifters had 10% higher values also after age 65. It appears that bone mass is higher in weight-loaded areas and lower in an unloaded region, such as the upper part of the skull, in exercising athletes. After cessation of the active career, the bone mass approaches that of the controls and after 65 years of age, no difference was found comparing ex-weight lifters and controls. Due to the apparent bone mass shift from unloaded skeletal regions to loaded skeletal regions that seems to take place in active athletes, the constructed ratio, BMD total body to BMD upper part of the skull, seems to discriminate the influence on the skeleton in a more sensitive way than measuring the BMD in defined skeletal regions on their own. By using this constructed ratio, the influence on bone mass of physical exercise early in life is also detectable at older ages.

To evaluate the accuracy of bone mineral composition determination by electron microprobe analysis (EDX) the measurements have been compared to instrumental neutron activation analysis (INAA) and chemical analysis (ICPES). Bone specimens from five femoral heads were used. The trabecular content of calcium (Ca) and phosphorus (P) was analyzed by the three different methods. The FDX method allows for a microstructural analysis of intact, methylmetacrylate-embedded, undecalcified bone and the measuring points can thus be distinctly identified centrally in each trabecula. The analysis yielded 25.8±0.7 wt% Ca and 10.5±0.1 wt % P, compared with 22.2±0.5 and 23.0±1.0 wt % Ca, and 9.83±0.21 and 10.02±0.44 wt % P for INAA and ICPES, respectively. The EDX analysis was calibrated by consecutive measurements of a hard, pressed tablet of hydroxyapatit of known content. The mean Ca content deviated with-0.38 wt % from the given content and P with-0.89 wt %. We could not verify any particular interference from the embedding procedure, however, it is possible that the relatively lower P content still may reflect this. The magnesium (Mg) concentration was 0.31±0.02 wt % by EDX and 0.26±0.02 wt % by INAA. The EDX analytical method provides a useful tool for simultaneous elemental quantification in bone. It has the advantage of permitting the use of cation bone biopsy material and thus allowing for a unique microstructural evaluation of the degree of mineralization. By comparison with other established methods, the assessment of accuracy and reliability indicates that the measurements are well in range for the major constituents, Ca and P, whereas INAA is more sensitive in determining trace elements.

Abstract.: The aim of this study was to evaluate the contribution of a low calcium diet to the cortical and trabecular osteoporosis seen in ovariectomized rats after 7 weeks on a low calcium diet and to investigate the effects of the bisphosphonate clodronate on this development of osteoporosis. Thirty-six mature, female Wistar rats were randomized into four groups: Ovx−B (bisphosphonate) and Ovx−C (control) were ovariectomized, and Sham−Ca (low calcium) and Sham+Ca (normal calcium) were sham operated. The first three groups were fed a low calcium diet (0.01%) and Sham+Ca normal rat chow (Ca 1.1%). The Ovx−B received 10 mg/kg s.c. clodronate daily for nine weeks, and Ovx−C, Sham−Ca, and Sham+Ca received the same volumes of saline. Bone mineral turnover measured as 85Sr-uptake was increased in all low calcium groups compared to Sham+Ca. The Sham+Ca femora had higher dry weight and ash weight than the other groups, and Ovx−C had higher dry weight compared with Ovx−B and Sham−Ca. Calcium content was lower in both Ovx groups compared to both Sham groups. Magnesium was lower in all groups compared to Sham+Ca and higher in Ovx−B compared with Ovx−C. In the femoral shaft, Sham+Ca had significantly higher ultimate bending moment, energy absorption, and deflection compared to the other three groups. Ultimate bending moment was higher in Sham−Ca than in Ovx−C. Stiffness was increased in both Sham+Ca and Ovx−B compared to Ovx−C. The maximum stress in the femoral midshaft was higher in Sham+Ca than in the other groups, and higher in Ovx−B than in Ovx−C. Histomorphometry showed increased medullary area in all low calcium groups compared to Sham+Ca and larger cortical area in Sham+Ca and Ovx−B compared to Ovx−C. Compared to Sham+Ca the trabecular bone volume was decreased to 30% in Sham−Ca and to 9% in Ovx−C, but was unchanged in Ovx−B. The low calcium diet generally increased bone mineral turnover and reduced the tibial bone volume. Femoral changes led to a reduction of cortical fracture strength and maximal stress. Ovariectomy in addition to a low calcium diet reduced femoral strength even more. Daily injections of clodronate to ovariectomized rats on a low calcium diet increased femoral shaft stiffness and maximum stress, and clodronate preserved both trabecular and cortical tibial bone volume completely.

The aim of this study was to investigate the effect of training on the in vivotibial structural strength during the development of post‐ovariectomy osteoporosis. Seventeen mature Wistar rats (215 g) were ovariectomized and randomized into two groups. The sedentary control group was kept cage confined, while 3 days postoperatively the trained group started treadmill running with high intensity for 1 h 5 days a week. All were given a low calcium diet (Ca 0.01%). After 8 weeks the animals were anaesthetized and the right lower legs fractured during muscle contraction in three‐point ventral bending. The left legs were fractured at the same level after removal of all soft tissues. Histomorphometry of the meta‐ and diaphysis of the distal tibiae was performed. Weight‐gain was higher in sedentary (108 g) than in trained (61 g) rats (P< 0.0001). There were no significant differences in mechanical results between the groups at in vivoor in vitrofracture. Correcting for weight‐gain differences did not change these results. Histomorphometry showed no differences between the groups. Corticosterone was higher in trained than in sedentary rats (P< 0.02), and corticosterone may have had a negative influence both on muscle and bone. The study could not show an effect of high intensity training in the early phase after ovariectomy on in vivoor in vitrofracture strength.

Based on the population of the city of Malmö, Sweden, we performed a retrospective cohort study. By choosing patients who had fractures of the upper end of the femur in the 1950s as an indication of senile osteoporosis, and by studying the roentgenographic records of their children from the 1950s and on' we concluded that this type of osteoporosis is not a condition that is aggravated in certain families. Offspring of parents who had a hip fracture in the 1950s are not more prone to have fractures than a control group.

Biopsy specimens were taken from parts of earlier fractured bones in seven patients with post-traumatic osteopenia and one healthy volunteer, who were all administered a double dose of tetracycline for the purpose of prelabelling. In the volunteer, specimens were taken from both the proximal tibia epiphysis and the iliac crest. The fraction of labelled surfaces and the rate of apposition were calculated. The results were also compared with normative data from the iliac crest. At least in the first year after fracture, post-traumatic osteopenia appears to be a condition with an increased appositional activity.

Résumé En 1990, une étude de contrôle est réalisée en se référant à tous les patients ayant eu des fractures de la diaphyse tibiale (n = 767) traitées dans le Département d'Orthopédie de Malmö entre 1949 et 1963. Lors de ce contrôle 231 patients vivaient toujours à Malmö. Tous les examens radiographiques de ce dernier groupe, à partir du moment de la fracture jusqu'à 1990 ont été étudiés et on a noté tous les cas de survenue d'arthrose de la hanche, du genou et de l'articulation de la cheville. Ces cas de fractures tibiales sont comparées à un groupe de contrôle de même âge et de même sexe. Le groupe des patients avec antécédent de fracture de la diaphyse tibiale présente une prédominance d'arthrose dans les membres inférieurs en comparaison avec les témoins. Nous n'avons relevé par contre aucune différence significative en comparant le risque d'arthrose dans le membre fracturé avec celui du côté intact. Nous concluons donc qu'il n'y a aucun risque d'avoir une arthrose post-traumatique après une fracture diaphysaire tibiale.