Modelling Human Locomotion to Inform Exercise Prescription for Osteoporosis

PURPOSE OF REVIEW

We review the literature on hip fracture mechanics and models of hip strain during exercise to postulate the exercise regimen for best promoting hip strength.

RECENT FINDINGS

The superior neck is a common location for hip fracture and a relevant exercise target for osteoporosis. Current modelling studies showed that fast walking and stair ambulation, but not necessarily running, optimally load the femoral neck and therefore theoretically would mitigate the natural age-related bone decline, being easily integrated into routine daily activity. High intensity jumps and hopping have been shown to promote anabolic response by inducing high strain in the superior anterior neck. Multidirectional exercises may cause beneficial non-habitual strain patterns across the entire femoral neck. Resistance knee flexion and hip extension exercises can induce high strain in the superior neck when performed using maximal resistance loadings in the average population. Exercise can stimulate an anabolic response of the femoral neck either by causing higher than normal bone strain over the entire hip region or by causing bending of the neck and localized strain in the superior cortex. Digital technologies have enabled studying interdependences between anatomy, bone distribution, exercise, strain and metabolism and may soon enable personalized prescription of exercise for optimal hip strength.

The Effect of Abaloparatide-SC on Fracture Risk Is Independent of Baseline FRAX Fracture Probability: A Post Hoc Analysis of the ACTIVE Study

Daily subcutaneous (SC) injections of the investigational drug abaloparatide-SC (80 mcg) for 18 months significantly decrease the risk of vertebral and nonvertebral fracture compared with placebo in postmenopausal women. We examined the efficacy of abaloparatide-SC as a function of baseline fracture risk, assessed using the FRAX tool. Baseline clinical risk factors (age, body mass index [BMI], prior fracture, glucocorticoid use, rheumatoid arthritis, and smoking) were entered into country-specific FRAX models to calculate the 10-year probability of major osteoporotic fractures, with or without femoral neck bone mineral density (BMD). The interaction between probability of a major osteoporotic fracture and treatment efficacy was examined by a Poisson regression. A total of 821 women randomized to placebo and 824 women to abaloparatide-SC, mean age 69 years in both groups, were followed for up to 2 years. At baseline, the 10-year probability of major osteoporotic fractures (with BMD) ranged from 2.3% to 57.5% (mean 13.2%). Treatment with abaloparatide-SC was associated with a 69% (95% confidence interval [CI] 38-85%) decrease in major osteoporotic fracture (MOF) and a 43% (95% CI 9-64%) decrease in any clinical fracture compared with placebo. For all outcomes, hazard ratios tended to decrease (ie, greater efficacy) with increasing fracture probability. Whereas the interaction approached significance for the outcome of any fracture (p = 0.11), there was no statistically significant interaction for any of the fracture outcomes. Similar results were noted when FRAX probability was computed without BMD. Efficacy of abaloparatide-SC to decrease the risk of major osteoporotic fracture or any clinical fracture in postmenopausal women with low BMD and/or prior fracture appears independent of baseline fracture probability. © 2017 American Society for Bone and Mineral Research.

Physical Activity for Strengthening Fracture Prone Regions of the Proximal Femur

PURPOSE OF REVIEW

Physical activity improves proximal femoral bone health; however, it remains unclear whether changes translate into a reduction in fracture risk. To enhance any fracture-protective effects of physical activity, fracture prone regions within the proximal femur need to be targeted.

RECENT FINDINGS

The proximal femur is designed to withstand forces in the weight-bearing direction, but less so forces associated with falls in a sideways direction. Sideways falls heighten femoral neck fracture risk by loading the relatively weak superolateral region of femoral neck. Recent studies exploring regional adaptation of the femoral neck to physical activity have identified heterogeneous adaptation, with adaptation principally occurring within inferomedial weight-bearing regions and little to no adaptation occurring in the superolateral femoral neck. There is a need to develop novel physical activities that better target and strengthen the superolateral femoral neck within the proximal femur. Design of these activities may be guided by subject-specific musculoskeletal modeling and finite-element modeling approaches.

Effect of monthly intravenous ibandronate injections on vertebral or non-vertebral fracture risk in Japanese patients with high-risk osteoporosis in the MOVER study

We examined the efficacy of intravenous (IV) ibandronate 1 mg/month in patient subgroups in the phase III MOVER study. Here we present results of analyses on the incidence of fractures in patients with prevalent vertebral fractures (1 or ≥2, and ≥3) at screening and femoral neck (FN) bone mineral density (BMD) T scores ≥-2.5 or <-2.5, and <-3.0 at baseline. The per-protocol set comprised 1134 patients (ibandronate 0.5 mg/month n = 376; ibandronate 1 mg/month n = 382; risedronate oral 2.5 mg/day n = 376). The incidence of vertebral fractures in patients with 1 or ≥2 prevalent vertebral fractures was 11.2 and 20.4 %, respectively, with ibandronate 1 mg/month, and 12.6 and 22.1 %, respectively, with risedronate. In patients with FN BMD T scores ≥-2.5 or <-2.5, the vertebral fracture incidence was 13.7 and 16.4 %, respectively, with ibandronate 1 mg/month, and 17.3 and 19.1 %, respectively, with risedronate. The incidence of non-vertebral fractures in patients with ≥2 prevalent vertebral fractures or FN BMD T score <-2.5 was 7.6 and 7.6 %, respectively, with ibandronate 1 mg/month, and 9.5 and 9.4 %, respectively, with risedronate. Fracture incidence was consistently lower, but not significant, with ibandronate 1 mg/month than with risedronate in patients with ≥2 prevalent vertebral fractures and FN BMD T score <-2.5. The efficacy of the fracture reduction of monthly IV ibandronate appears consistent and seemingly independent of the number of prevalent vertebral fractures or baseline BMD values.

Head-Neck Osteoplasty has Minor Effect on the Strength of an Ovine Cam-FAI Model: In Vitro and Finite Element Analyses

BACKGROUND

Osteochondroplasty of the head-neck region is performed on patients with cam femoroacetabular impingement (FAI) without fully understanding its repercussion on the integrity of the femur. Cam-type FAI can be surgically and reproducibly induced in the ovine femur, which makes it suitable for studying corrective surgery in a consistent way. Finite element models built on quantitative CT (QCT) are computer tools that can be used to predict femoral strength and evaluate the mechanical effect of surgical correction.

QUESTIONS/PURPOSES

We asked: (1) What is the effect of a resection of the superolateral aspect of the ovine femoral head-neck junction on failure load? (2) How does the failure load after osteochondroplasty compare with reported forces from activities of daily living in sheep? (3) How do failure loads and failure locations from the computer simulations compare with the experiments?

METHODS

Osteochondroplasties (3, 6, 9 mm) were performed on one side of 18 ovine femoral pairs with the contralateral intact side as a control. The 36 femurs were scanned via QCT from which specimen-specific computer models were built. Destructive compression tests then were conducted experimentally using a servohydraulic testing system and numerically via the computer models. Safety factors were calculated as the ratio of the maximal force measured in vivo by telemeterized hip implants during the sheep's walking and running activities to the failure load. The simulated failure loads and failure locations from the computer models were compared with the experimental results.

RESULTS

Failure loads were reduced by 5% (95% CI, 2%-8%) for the 3-mm group (p = 0.0089), 10% (95% CI, 6%-14%) for the 6-mm group (p = 0.0015), and 19% (95% CI, 13%-26%) for the 9-mm group (p = 0.0097) compared with the controls. Yet, the weakest specimen still supported more than 2.4 times the peak load during running. Strong correspondence was found between the simulated and experimental failure loads (R² = 0.83; p < 0.001) and failure locations.

CONCLUSIONS

The resistance of ovine femurs to fracture decreased with deeper resections. However, under in vitro testing conditions, the effect on femoral strength remains small even after 9 mm correction, suggesting that femoral head-neck osteochondroplasty could be done safely on the ovine femur. QCT-based finite element models were able to predict weakening of the femur resulting from the osteochondroplasty.

CLINICAL RELEVANCE

The ovine femur provides a seemingly safe platform for scientific evaluation of FAI. It also appears that computer models based on preoperative CT scans may have the potential to provide patient-specific guidelines for preventing overcorrection of cam FAI.

Biomechanical optimization of subject-specific implant positioning for femoral head resurfacing to reduce fracture risk

Peri-prosthetic femoral neck fracture after femoral head resurfacing can be either patient-related or surgical technique-related. The study aimed to develop a patient-specific finite element modelling technique that can reliably predict an optimal implant position and give minimal strain in the peri-prosthetic bone tissue, thereby reducing the risk of peri-prosthetic femoral neck fracture. The subject-specific finite element modelling was integrated with optimization techniques including design of experiments to best possibly position the implant for achieving minimal strain for femoral head resurfacing. Sample space was defined by varying the floating point to find the extremes at which the cylindrical reaming operation actually cuts into the femoral neck causing a notch during hip resurfacing surgery. The study showed that the location of the maximum strain, for all non-notching positions, was on the superior femoral neck, in the peri-prosthetic bone tissue. It demonstrated that varus positioning resulted in a higher strain, while valgus positioning reduced the strain, and further that neutral version had a lower strain.

Adherence to oral bisphosphonates and the risk of subtrochanteric and femoral shaft fractures among female medicare beneficiaries

Previous studies have shown an association between duration of bisphosphonate use and atypical femur fractures. This cohort study showed an increasingly higher risk of subtrochanteric and femoral shaft fractures among those who were more adherent to oral bisphosphonates.

INTRODUCTION

Long-term use of oral bisphosphonates has been implicated in an increased risk of atypical femur fractures located in subtrochanteric and femoral shaft regions. Another measure of drug exposure, medication adherence, however, has not been investigated.

METHODS

Among all Medicare fee-for-service female beneficiaries from 2006-2010, we followed 522,287 new bisphosphonate users from their index prescription until being censored or having a primary diagnosis of closed subtrochanteric/femoral shaft or intertrochanteric/femoral neck fractures. Data about radiographs of fracture site and features were not available. Adherence was classified according to the medication possession ratio (MPR) as the following: MPR < 1/3 as less compliant, MPR ≥ 1/3- < 2/3 as compliant, and MPR ≥ 2/3 as highly compliant. Alternative cutoff points at 50 and 80% were also used. Survival analysis was used to determine the cumulative incidence and hazard of subtrochanteric/femoral shaft or intertrochanteric/femoral neck fractures.

RESULTS

There was a graded increase in incidence of subtrochanteric/femoral shaft fractures as the level of adherence increased (Gray's test, P < 0.001). The adjusted hazard ratio (HR) for the highly compliant vs. the less compliant was 1.23 (95% Confidence Interval [CI] 1.06-1.43) overall, became significant after 2 years of follow-up (HR = 1.51, 95% CI 1.06-2.15) and reached the highest risk in the fifth year (HR = 4.06, 95% CI 1.47-11.19). However, age-adjusted incidence rates of intertrochanteric/femoral neck fractures were significantly lower among highly compliant beneficiaries, compared to less compliant users (HR = 0.69, 95% CI 0.66-0.73). Similar results were obtained when the cutoff points for being compliant and highly compliant were set at 50 and 80 %, respectively.

CONCLUSIONS

Subtrochanteric/femoral shaft fractures, unlike intertrochanteric/femoral neck fractures, are positively associated with higher adherence to long-term (≥3 years) oral bisphosphonates in the elderly female Medicare population.

The incidence of vitamin D deficiency amongst patients with a femoral neck fracture: are current bone protection guidelines sufficient ?

Vitamin D is required for calcium homeostasis and bone metabolism. This prospective observational study examined the incidence of vitamin D deficiency amongst patients with a fracture of the femoral neck, and the correlation between pre-admission use of bone-protection medication and vitamin D levels. Vitamin D assays were available in 75 out of 151 patients admitted with a hip fracture in February-March 2012; the assays were performed within one week of admission and surgery. The incidence of suboptimal vitamin D levels was 90% (68/75), with severe deficiency (<15nmol/l) or deficiency (<30nmol/l) seen in 71% (53/75). Only 7 patients were on bone protection medication at the time of admission, and all of them had suboptimal vitamin D levels. This suggests that the prevention is practically inexistent or at best insufficient. According to the literature, vitamin D deficiency is also associated with falls and maybe with outcome of surgery. Current management strategies may not be sufficient to address vitamin D deficiency and are overlooking an important and potentially modifiable risk factor.

Hypovitaminosis D as a risk factor of hip fracture severity

SUMMARY

In a cross-sectional study including 324 patients older than 65 years admitted to our hospital for osteoporotic hip fracture, we found that those patients with a more severe vitamin D deficiency had more severe osteoporotic hip fractures (Garden grades III-IV and Kyle III-IV).

INTRODUCTION

To identify possible differences in baseline characteristics of patients with different types of osteoporotic hip fracture.

METHODS

Cross-sectional study including consecutive individuals over 65 admitted to our hospital for osteoporotic hip fracture over a year. Demographic data, fracture type, comorbidities, history of osteoporosis, functional capacity, nutritional status and vitamin D storage were evaluated.

RESULTS

We included 324 patients (83 ± 7 years, 80% women). Two hundred sixteen patients (67%) had vitamin D deficiency (25OHD3 <25 ng/ml). In patients with severe femoral neck or intertrochanteric fractures (Garden III-IV and Kyle III-IV), vitamin D deficiency was more frequent (74%) and severe (25OHD3 20 ± 15 ng/ml) than in patients with less severe fractures (57%, 25OHD3 26 ± 21 ng/ml). Forty-three percent of patients had previous fractures. Only 15% of patients had been previously diagnosed with osteoporosis and 10% were receiving treatment. Patients receiving vitamin D supplements have higher 20OHD3 levels and less severe fractures.

CONCLUSIONS

Although vitamin D levels are not different between patients with intracapsular or extracapsular hip fractures, a more severe vitamin D deficiency seems to be associated to more severe osteoporotic hip fractures. A prior vitamin D supplementation could avoid a higher severity of these fractures.

[Morphological analysis of bone dynamics and metabolic bone disease. Does bisphosphonate treatment cause severely suppressed bone turnover (SSBT) ?]

Bisphosphonates are anti-resorptive drug and increase both bone strength and toughness. However, their long term treatment oversuppresses bone turnover and promotes advanced glycation end-products in bone tissue, resulting in low bone quality. These conditions are called "severely suppressed bone turnover (SSBT) " , and can cause "atypical" , low-impact fractures of the femoral subtrochanteric or shaft. It is evident that bisphosphonates prevent fracture risk in vertebral body or femoral neck and improve quality of life in patients with osteoporosis, but clinicians, especially bone specialists, have to keep the associations between bisphosphonate use and SSBT in mind. Rational approach to atypical femoral subtrochanteric÷shaft fractures should be determined in near future.

Role of the orthopaedic in fragility fracture and in the prevention of a new fracture: SIOT 2009 recommendations

The progressive aging of the population inevitably leads to an increase in all age-related diseases, with osteoporosis arising as a health and social priority. Fragility fractures, resulting by Osteoporosis, may have important consequences such as hospitalizations with long periods of immobility, need of surgery, increased risk of disability and partial or complete loss of autonomy in the ordinary activities of daily life and related economical burden. It is therefore essential to implement immediately a tertiary prevention to reduce the risk of further fractures through a diagnostic-therapeutic evidence-based pathway. So, starting from the fracture, the orthopaedic surgeon is meant to play an essential role in the management of osteoporotic patients, both to reduce the risk of further fractures and improve long-term outcome in these people, thus lowering the health and life quality downward spiral that often results in fractures in the elderly.

[Zoledronic acid reduces risk of any new clinical fracture and risk of death after surgical repair of a low-trauma hip fracture]

The most common treatment option for postmenopausal osteoporosis are the bisphosphonates which inhibit osteoclast function. Bisphosphonates interfere with cellular metabolism and in large clinical trials reduce risk of vertebral and non-vertebral fractures. Zoledronic acid is a potent bisphosphonate also approved for the treatment of postmenopausal osteoporosis. In addition zoledronic acid reduce relative risk of any new clinical fracture after surgical repair of low-trauma hip fracture. Also the reduction in the relative risk of death was observed after repeated once-yearly intravenous infusion. In conclusion, this is another interesting option for the treatment of the patients affected with osteoporosis and previous hip fractures.

A multidisciplinary approach in patients with femoral neck fracture on an osteoporotic basis

INTRODUCTION

Osteoporosis is a common affection characterized by a reduction of bone mass that affects mostly women after menopause. It currently leads to fractures, especially of the spine and hip thus enhancing the costs of medical care. There are many factors that contribute to its development, leading to various strategy lines to deal with it.

AIM

The present study aims at showing how a multidisciplinary, multifactorial approach can be effective in treating and preventing new osteoporotic fractures.

MATERIAL AND METHODS

The study included 17 patients that had replacement arthroplasty for femoral neck fractures. Bone tissue fragments were obtained from all of them and analyzed by pathology specialists. A dual-energy X-ray absorptiometry exam was also performed on each patient. In the end, the data was collected and processed by rehabilitation experts in order to establish proper therapy.

RESULTS

The hip fracture incidence was two times more frequent in women than in men, higher in the 71-80-year-old group. By analyzing the bone fragments atrophy could be seen, especially in the femoral neck as well as lamellae and osteon reduction and bone architecture alterations.

CONCLUSIONS

Surgical or pharmacological treatments alone are not sufficient for handling osteoporosis. Strategies such as preventing falls, a proper diet, treating associated conditions and a well-established exercise program need to be considered. Specialists from several areas such as pathology, orthopedics, endocrinology, internal medicine and rehabilitation should work together to design the best approach to deal with osteoporosis.

Targeted exercises against hip fragility

SUMMARY

Compared to high-impact exercises, moderate-magnitude impacts from odd-loading directions have similar ability to thicken vulnerable cortical regions of the femoral neck. Since odd-impact exercises are mechanically less demanding to the body, this type of exercise can provide a reasonable basis for devising feasible, targeted bone training against hip fragility.

INTRODUCTION

Regional cortical thinning at the femoral neck is associated with hip fragility. Here, we investigated whether exercises involving high-magnitude impacts, moderate-magnitude impacts from odd directions, high-magnitude muscle forces, low-magnitude impacts at high repetition rate, or non-impact muscle forces at high repetition rate were associated with thicker femoral neck cortex.

METHODS

Using three-dimensional magnetic resonance imaging, we scanned the proximal femur of 91 female athletes, representing the above-mentioned five exercise-loadings, and 20 referents. Cortical thickness at the inferior, anterior, superior, and posterior regions of the femoral neck was evaluated. Between-group differences were analyzed with ANCOVA.

RESULTS

For the inferior cortical thickness, only the high-impact group differed significantly (approximately 60%, p = 0.012) from the reference group, while for the anterior cortex, both the high-impact and odd-impact groups differed (approximately 20%, p = 0.042 and p = 0.044, respectively). Also, the posterior cortex was approximately 20% thicker (p = 0.014 and p = 0.006, respectively) in these two groups.

CONCLUSIONS

Odd-impact exercise-loading was associated, similar to high-impact exercise-loading, with approximately 20% thicker cortex around the femoral neck. Since odd-impact exercises are mechanically less demanding to the body than high-impact exercises, it is argued that this type of bone training would offer a feasible basis for targeted exercise-based prevention of hip fragility.

[Economics of medicament therapies for osteoporosis]

For treatment of osteoporosis, medical costs range within 10% among administrations of alfacalcidol, raloxifene and weekly alendronate, because costs of the drugs are shared about 50% of medical costs. Medical costs of the patients suffered from mild lumbago, severe lumbago and femoral neck fracture are compared between the patients with and without the medicament therapies. Preventions of lumbago and fracture by the drugs reduce maximally 16.5% of medical costs. Economics of various therapies to prevent femoral neck fracture in whole Japan show that hip protector gains 73.1 billion yen and medicament therapies lose minimally 826.9 billion yen annually.

Salvage of failed treatment of femoral neck fractures

The number of patients treated for femoral neck fractures continues to increase. Although most fractures will heal, reported rates of nonunion and osteonecrosis are cause for concern; therefore, implementation of effective salvage strategies is important. The choice of salvage strategy generally is guided by patient age, remaining bone quality, the status of the articular surface of the hip joint, and the viability of the femoral head. Nonunions in patients younger than 60 years are typically treated with valgus-producing osteotomies, which convert shear forces to compressive forces and have demonstrated relatively high union rates. The role of various vascularized and nonvascularized bone grafts remains undefined. Nonunions in patients older than 60 years are typically salvaged with some form of hip arthroplasty. Both hemiarthroplasty and total hip arthroplasty can be effective. Surgical challenges include osteopenic bone; bony defects from hardware; and contracted, scarred, and shortened limbs. Careful attention to detail during surgery is necessary to avoid complications and provide durable reconstructions in this setting.

[Evaluation of visual functions in elderly patients with femoral neck fracture]

OBJECTIVES

We aimed at assessing the visual functions in elderly patients with femoral neck fracture and to compare the results with age-matched controls in this three-year prospective study.

PATIENTS AND METHODS

Seventy-one patients with a history of fall related hip fracture (39 females, 32 males; mean age 76.3+/-9.7 years; range 64 to 90 years) and who were diagnosed with femoral neck fracture after direct graphy were treated by means of bipolar partial prosthesis and they were contacted postoperatively or prior to discharge to participate in the study. Visual acuity, depth perception, the presence of cataract in the red reflex were evaluated. A dilated fundus and slit-lamp examination were performed if possible. On completion of the examination, the ophthalmologist documented the causes of any visual impairment found. Control group was comprised of age-matched 40 subjects (22 females, 18 males; mean age 73.2+/-7.6 years; range 62 to 90 years) who applied to ophtalmology clinic for routine examination.

RESULTS

The visual acuity was significantly decreased in the patient group as was stereopsis (p<0.05). We found no difference between the study group and the controls when we evaluate the distribution of self reported eye disease and eye disease found on ocular examination. The rate of cases who reported not usually wearing glasses was 35% while it was 5% in the control group. When we evaluate the time since last examination, 38% of cases had not had an eye examination for over four years, as compared with 22.5% of controls.

CONCLUSION

This study shows that elderly people should have their eyes tested at least once every two years, refractive errors should be corrected and eye diseases should be treated to decrease the risk of fall-related femoral neck fractures.

[Dynamic flamingo therapy]

A long follow up study of one minute unipedal standing therapy 3 times in a day to prevent femoral neck osteoporosis that have started from 1993 was reported. The registration from July 1993 to March 2004 were 86 cases which measured the femoral neck bone mineral density (BMD) according to dual energy x-ray absorptiometry (DXA) (Hologic QDR 1000 and 2000) in a follow-up period. Average age at starting exercise was 67.9 years old. All cases were female who were registered in our university hospital. The result of unipedal exercise evaluated by the femoral neck BMD was described as follows : The increased cases of BMD were 15/24 (62.5%) post exercise 3 months, 15/37 (40.5%) post 6 months, and 12/21 (57.1%) post one year, 8/25 (32%) post 3 years, 7/13 (53.8%) post 5 years and 1/3 (33.3%) post 10 years. We have no fracture cases in which continued exercise in follow-up period. According to a randomized controlled study of unipedal standing balance therapy to clinically defined high-risk elderly individuals a therapy group reduced fall times by a significant difference than non-therapy group. We conclude that unipedal standing therapy is efficacious against femoral neck osteoporosis and fractures.

[Evidence for efficacy of active vitamin D3 as an anti-osteoporotic drug]

Active vitamin D3 has been most widely used in Japan for the treatment of osteoporosis. Although it mildly increases bone mineral density, it has little consistent effect on bone metabolic markers, and clinical evidence for its efficacy as a fracture-preventing drug is rather weak. Recent reports suggest that (active) vitamin D3 may prevent fracture incidence not only by promoting intestinal calcium absorption but also by improving neuromuscular function to reduce the number of falls.

[Epidemiology of femoral neck fractures in Puglia (Italy): an analysis of existing data]

The aim of this study was to describe the epidemiology of femoral neck fractures in Puglia (Italy) by analysing hospital discharge records from 1998 to 2005 and mortality data from 1998 to 2003. In total, 41,354 admissions for femoral neck fractures were recorded, 75% of which in females. The mean age of patients was 78 years (73 in males, 79 in females). Approximately 70% of patients below 50 years of age were male, while above age 50, only 23% of patients were male. Yearly admission rates increased from 1998 to 2005. Mortality records recorded 1,031 deaths due to femoral neck fracture with a decreasing trend in mortality rates in the years considered. Fractures in males were most commonly associated with work related accidents and motor vehicle accidents. In females most fractures were related to home accidents. These results may be used to guide prevention strategies.

[Daily practice using the guidelines for prevention and treatment of osteoporosis. How do we realize the bone quality in routine practice using Japanese guideline for osteoporosis prevention and treatment?]

Bone quality is thought to encompass the structural and material properties of bone that are affected by turnover rate. The concept of bone quality is included in Japanese Guideline for Osteoporosis prevention and treatment. Evidence has accumulated that collagen cross-links play important roles in bone strength. We have demonstrated that the quantitative and qualitative deterioration of lysyl oxidase controlled and non-enzymatic cross-links (Advanced glycation end products, AGEs, Pentosidine) of collagen in patients with osteoporotic femoral neck fracture cases might be affected by hyperhomocysteinemia (Saito M, Calcif Tissue Int, 2006), oxidative stress, vitamin B status (Saito M, Osteoporos Int, 2006) . Recently, Shiraki et al. demonstrated that a functional polymorphism in methylenetetrahydrofolate reductase (MTHFR) polymorphism, T allele (C677T), may be a risk factor for future fracture in addition to the traditional risk factors (Shiraki M, Saito M, et al., J Bone Miner Metab, in press). In addition, we have reported that a higher urinary pentosidine was an independent risk factor, for vertebral fracture in a 5-year prospective study in Japanese women (Shiraki M, Saito M, et al., J Bone Miner Metab, 2008). If confirmed in large, prospective trials, measurement of serum homocysteine and serum or urinary excretion of pentosidine might be characterized as markers reflecting bone collagen deterioration.

[Daily practice using the guidelines for prevention and treatment of osteoporosis. Osteoporosis prevention and use of the new management guideline for osteoporosis]

Now that the goal of osteoporosis management has been clearly defined as prevention of osteoporosis-associated fractures, prevention strategy for these fractures becomes compellingly important. While the new management guideline for osteoporosis places an overriding emphasis on the prevention of osteoporosis, it goes on to stress the importance of pharmacological therapy even in patients at high risk of developing fractures, in whom pharmacological therapy would not be indicated in the earlier guideline, thus recommending that pharmacological therapy be extended to a larger proportion of patients who may benefit from such treatment. In this therapeutic strategy, not only pharmacological therapy in middle-aged and elderly individuals in perimenopause will be of vital importance, as in the earlier guideline, but also non-pharmacological intervention through modification of everyday lifestyle habits will become increasingly important in adolescents and young female adults in their developmental years. It is thus hoped that adherence to the new guideline will lead to a decrease in the frequency of reported fractures, including femoral neck fractures, in Japan.

[Clinical application of undercarboxylated osteocalcin]

Undercarboxylated osteocalcin (ucOC) is a sensitive marker of vitamin K (VK) status. Serum ucOC concentration in perimenopausal women is significantly higher than that in premenopausal women. In addition, serum ucOC concentration is closely associated with not only FSH concentration but also estradiol concentration. Serum ucOC concentration rapidly increases in women after bilateral oophorectomy. The effect of hormone therapy (HT) on alternate days on ucOC concentration is weaker than the effect of HT daily and ucOC concentration after 12 months of HT daily may be decreased due to the conversion of ucOC to carboxylated OC by the effect of VK through increased TG induced by oral conjugated equine estrogen (CEE) . Additionally, the effect of HT with transdermal estradiol on ucOC concentration in women is weaker than the effect of HT with oral CEE.

Metal-metal hip resurfacing: solution to a nonexistent problem

Second-decade survivorship may not be as predictable for total hip resurfacing as for THA. The operation requires more surgical exposure and is more difficult to perform reliably than a large-head metal-on-metal THA. Perhaps we have solved some of our prior dilemmas and created some new risks for the future with hip resurfacing arthroplasty, with many questions remaining unanswered. For now, we will stick with what works and solves real clinical problems for both the surgeon and the patient: the conventional THA with a large-head metal-on-metal articulation.

[Absolute risk for fracture and WHO guideline. Fracture risk assessment by quantitative ultrasound of bone ; its advantage and disadvantage]

Quantitative ultrasound (QUS) of bone is a radiation-free technique that measures bone mass. Therefore QUS machines can be operated anywhere and by anyone without any medical license in Japan. However, reproducibility of QUS is relatively low and only peripheral bone can be measured. Retrospective and prospective studies have suggested that low-bone ultrasound of the calcaneus is associated with an increased risk for hip, especially for trochanteric factures, but it is inferior to the association between bone mineral density measured at the hip and hip fractures. QUS is a valid and cost-effective tool to assess fracture risk.

[Bone diseases with Pain: Femoral neck fracture]

Although it is obvious that femoral neck fracture shows the worst prognosis of the physical function among variously osteoporotic symptoms, it is true that the fracture is the most painful disease. The fracture is treated to recover the physical function, instead of relieving the pain. Femoral neck fracture is classified into medial fracture broken at the inside of the capsule of hip joint and lateral fracture broken at the outside. A foreign paper emphasized the efficacy of early surgical treatment to relieve the pain, but in late day, correct surgery under the control of complications is revealed to introduce a good physical function and low mortality in Japan, as almost all the patients with femoral neck fracture is 80 years old or over, and have variously severe complications. Even in the delayed operation, early intervention of rehabilitation leads lower mortality and better prognosis of physical function. Femoral neck fracture is recently treated by those advanced surgery and rehabilitation, but number of independent patient reduced by two third and one of bed-ridden patient increased by 2.5 times one year after the fracture. So it would be important that the occurrence of femoral neck fracture reduced by increase of bone strength, prevention of falls, and adaptation of hip protector.

Effect of beta-blockers on bone mass and biomechanical parameters of the femoral neck in males with acute myocardial infarction

OBJECTIVES

Evaluate the effect of cardioselective beta-blockers on bone mass and biomechanical properties of the femoral neck in males with acute myocardial infarction.

METHODS

Forty males with acute myocardial infarction were studied during one year. Seventy-five percent of the patients (30 patients) were treated with cardioselective beta-blockers and 10 were not similarly treated. A hip densitometry was performed upon release and one year later. The BMD was measured in the femoral neck and in biomechanical elements obtained by DXA.

RESULTS

Both groups had similar clinical conditions at the beginning of the study and after a one-year follow-up. No differences in the BMD (0.934+/-0.12 vs. 0.921+/-0.14) were observed in the group without beta-blockers or in the group with beta-blockers (0.980+/-0.12 vs. 0.977+/-0.12). No differences were observed in the measured structural parameters.

CONCLUSION

The cardioselective beta-blockers do not modify bone mass or the structural bone parameters in males with acute myocardial infarction.

Metal-on-metal hip resurfacing: what have we learned?

Surface hip arthroplasty has many attractive features for young, active patients, particularly because of the conservative nature of this treatment and its ability to preserve femoral bone. It is more anatomic and physiologic than stem-type hip replacements, and it represents a truly minimally osteoinvasive procedure, with no penetration into the femoral intramedullary canal. In addition, the construct has increased stability because of the near-normal diameter of the femoral component compared with most conventional hip replacement components. Although the short- to midterm clinical results for metal-on-metal hybrid hip resurfacing implants are definitely superior to those of earlier generations of resurfacing implants, the results of conventional total hip replacement using contemporary designs and bearing materials have also improved. As a result, it is imperative to assess what is known about the safety and efficacy of resurfacing to refine the indications and technique to improve the overall results and durability.

Secondary prevention of fragility fractures: are we following the guidelines? Closing the audit loop

INTRODUCTION

The aim of this study was to determine whether orthopaedic surgeons follow the British Orthopaedic Association (BOA) guidelines for secondary prevention of fragility fractures.

PATIENTS AND METHODS

A retrospective audit was conducted on patients with neck of femur fractures treated in our hospital between October and November 2003. A re-audit was conducted during the period August to October 2004.

RESULTS

There were 27 patients in the initial study period. Twenty-six patients (96%)had full blood count measured with LFT and bone-profile measured in 18 patients (66%). Only nine patients (30%)had treatment for osteoporosis (calcium and vitamin D). Only one patient was referred for DEXA scan. Steps were taken in the form of creating better awareness among the junior doctors and nurse practitioners of the BOA guidelines. In patients above 80 years of age, it was decided to use abbreviated mental score above 7 as a clinical criteria for DEXA referral. A hospital protocol based on BOA guidelines was made. A re-audit was conducted during the period August to October 2004. There were 37 patients. All had their full blood count and renal profile checked (100%). The bone-profile was measured in 28 (75.7%) and LFT in 34 (91.9%) patients. Twenty-four patients (65%) received treatment in the form of calcium + vitamin D (20) and bisphosphonate (4). DEXA-scan referral was not indicated in 14 patients as 4 were already on bisphosphonates and for 10 patients their abbreviated mental score was less than 7. Among the remaining 23 patients, 9 patients (40%) were referred for DEXA scan. This improvement is statistically significant (P = 0.03, chi square test).

DISCUSSION AND CONCLUSIONS

The re-audit shows that, although there is an improvement in the situation, we are still below the standards of secondary prevention of fragility fractures with 60% of femoral fragility fracture patients not being referred for DEXA scan. A pathway lead by a fracture liaison nurse dedicated to osteoporotic fracture patients should improve the situation.

[Treatment of osteoporosis from the socioeconomic perspectives]

Health economic evaluation for osteoporosis suffers from methodological limitations. For example, osteoporosis results in various types of fractures each with different impact on patients. Another example is that some therapeutic drugs have extraskeletal benefits and adverse events. Osteoporosis and resultant fracture has profound effects on patients' life expectancy and quality of life, which, however, is not well understood. To promote the health economic evaluation for osteoporosis is our urgent research project in Japan.

[Antiosteoporosis medication: useful monitoring, and how long should such treatment be continued?]

The improved options for effective treatment of osteoporosis and the shift to treatment strategies based on each patient's absolute fracture risk raise new questions in daily clinical care. Which patient should have what osteoprotective therapy and when and for how long? What techniques can be used to assess the individual effects of novel therapeuties? Are the results yielded by these techniques affected by concomitant factors? What specific characteristics need to be taken account of in rheumatological clinics and how should we deal with these? What is the impact of patient compliance on the assessment of therapeutic effects? This review is intended to shed some light on these questions and on the new DVO guidelines in daily practice with reference to the ambulatory setting.

[Treatment of primary osteoporosis in men]

Primary osteoporosis in men occurs less frequently and thus tends to be less noticed than that in women. However, once a femoral neck fracture occurs in men, patients are more likely to be disabled than women. Thus, implementing treatments of osteoporosis before the occurrence of femoral neck fractures is important in terms of men's quality of life. Several studies have shown that bisphosphonate is a mainstay of the treatment of the disorder, by increasing bone mineral density and reducing the risk of vertebral fractures.