Quantifying the effect of hand preference on upper limb bone mineral and soft tissue composition in young and elderly women by dual-energy X-ray absorptiometry

Application of Machine Learning to Osteoporosis and Osteopenia Screening Using Hand Radiographs

PURPOSE

Fragility fractures associated with osteoporosis and osteopenia are a common cause of morbidity and mortality. Current methods of diagnosing low bone mineral density require specialized dual x-ray absorptiometry (DXA) scans. Plain hand radiographs may have utility as an alternative screening tool, although optimal diagnostic radiographic parameters are unknown, and measurement is prone to human error. The aim of the present study was to develop and validate an artificial intelligence algorithm to screen for osteoporosis and osteopenia using standard hand radiographs.

METHODS

A cohort of patients with both a DXA scan and a plain hand radiograph within 12 months of one another was identified. Hand radiographs were labeled as normal, osteopenia, or osteoporosis based on corresponding DXA hip T-scores. A deep learning algorithm was developed using the ResNet-50 framework and trained to predict the presence of osteoporosis or osteopenia on hand radiographs using labeled images. The results from the algorithm were validated using a separate balanced validation set, with the calculation of sensitivity, specificity, accuracy, and receiver operating characteristic curve using definitions from corresponding DXA scans as the reference standard.

RESULTS

There was a total of 687 images in the normal category, 607 images in the osteopenia category, and 130 images in the osteoporosis category for a total of 1,424 images. When predicting low bone density (osteopenia or osteoporosis) versus normal bone density, sensitivity was 88.5%, specificity was 65.4%, overall accuracy was 80.8%, and the area under the curve was 0.891, at the standard threshold of 0.5. If optimizing for both sensitivity and specificity, at a threshold of 0.655, the model achieved a sensitivity of 84.6% at a specificity of 84.6%.

CONCLUSIONS

The findings represent a possible step toward more accessible, cost-effective, automated diagnosis and therefore earlier treatment of osteoporosis/osteopenia.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

Similar stretch reflexes and behavioral patterns are expressed by the dominant and nondominant arms during postural control

Limb dominance is evident in many daily activities, leading to the prominent idea that each hemisphere of the brain specializes in controlling different aspects of movement. Past studies suggest that the dominant arm is primarily controlled via an internal model of limb dynamics that enables the nervous system to produce efficient movements. In contrast, the nondominant arm may be primarily controlled via impedance mechanisms that rely on the strong modulation of sensory feedback from individual joints to control limb posture. We tested whether such differences are evident in behavioral responses and stretch reflexes following sudden displacement of the arm during posture control. Experiment 1 applied specific combinations of elbow-shoulder torque perturbations (the same for all participants). Peak joint displacements, return times, end point accuracy, and the directional tuning and amplitude of stretch reflexes in nearly all muscles were not statistically different between the two arms. Experiment 2 induced specific combinations of joint motion (the same for all participants). Again, peak joint displacements, return times, end point accuracy, and the directional tuning and amplitude of stretch reflexes in nearly all muscles did not differ statistically when countering the imposed loads with each arm. Moderate to strong correlations were found between stretch reflexes and behavioral responses to the perturbations with the two arms across both experiments. Collectively, the results do not support the idea that the dominant arm specializes in exploiting internal models and the nondominant arm in impedance control by increasing reflex gains to counter sudden loads imposed on the arms during posture control.NEW & NOTEWORTHY A prominent hypothesis is that the nervous system controls the dominant arm through predictive internal models and the nondominant arm through impedance mechanisms. We tested whether stretch reflexes of muscles in the two arms also display such specialization during posture control. Nearly all behavioral responses and stretch reflexes did not differ statistically but were strongly correlated between the arms. The results indicate individual signatures of feedback control that are common for the two arms.

Intergender Hand Transplant: A Sex Congruent Hand Transformation

ABSTRACT

Hand and upper-extremity transplantation restore severely damaged limbs that cannot be repaired with conventional surgical techniques. Over the past 20 years, more than 200 vascularized composite allotransplantations have been performed worldwide, among them 7 were cases of sex unmatched hand transplants. The long term effects of recipient sex hormones and nerve regeneration on the sexually dimorphic physical features of donor upper extremity have not been described previously. We report a case of sex congruent transformation of hand morphology in an intergender hand transplant.

Capitellum fractures: Treatment with headless screws and outcomes

Objectives

This study aims to present the results of 21 patients with capitellum fractures treated with open reduction and headless screws by a single experienced surgeon.

Patients and methods

Twenty-one patients (13 males, 8 females; mean age 39 years; range, 18 to 63 years) who were admitted to our clinic between June 2011 and January 2018 with the diagnosis of capitellum fracture and followed-up for a mean period of 45 months (range, 12 to 90 months) were included in this retrospective study. The fractures were fixed with headless cannulated screws by a single surgeon.

Results

The mean range of motion was 102° (range, 65° to 140°) during flexion-extension and 165° (range, 130° to 180°) during supination-pronation. The mean preoperative visual analog scale (VAS) score was 8.5 (range, 6 to 10), whereas the mean postoperative VAS score was 2.2 (range, 0 to 6). According to the Mayo Elbow Performance score, nine patients were evaluated as excellent, six patients as good, four patients as fair, and two as poor. The mean Quick-Disabilities of the Arm, Shoulder and Hand score was 25.1 (range, 4 to 57). Avascular necrosis developed in three patients (14%) and heterotopic ossification was detected in one patient (4%).

Conclusion

Capitellum fractures are difficult to diagnose and treat, and good results can only be achieved by an accurate diagnosis, careful surgical technique, and stable fixation. Larger and more comprehensive studies are required to establish a generalization and more accurate inferences on this limitedly studied subject.

Footedness related differences in femoral bone mineral density in elderly women with osteoporosis

Purpose: The presumed link between lateralized habitual motor activity and bilateral skeletal asymmetry, as result of bone functional adaptation, is the basis for inferences about bone mineral distribution; consequently, bone loss and osteoporosis. As there is no research connecting directly footedness with osteoporosis, the present study was designed to investigate their relation, in elderly women with osteoporosis.Methods: A sample of 420 white, Caucasian race women, older than 65 years, with previous diagnosis of osteoporosis, was recruited for the study. Finally, 164 women met the inclusion criteria and participated. The femoral neck and total hip bone mineral density (BMD) differences between right and left hips of 105 right-footed and 59 non-right-footed women, and the between footedness groups differences of the above right-left BMD differences, were measured with Dual-energy X-ray Absorptiometry (DXA).Results: In right-footers, total hip right-left BMD differences were statistically significant, favoring left femur [t(104) = -2.79, p < .01, two tailed]. In non-right-footers, femoral neck right-left BMD differences were statistically significant, favoring right femur [t(58) =2.025, p < .05, two tailed]. Femoral neck and total hip right-left BMD differences of right- versus non-right-footed women were statistically insignificant.Conclusion: The dominance of the right lower limb had an asymmetric effect on left total hip BMD, while non-right-footedness favored right femoral neck BMD. The findings highlighted the influence of load bearing effects of the body weight and muscle contractions on femoral BMD. We noted a possible association between footedness and BMD, as a result of bone functional adaptation.

Quantifying shortening of the fractured clavicle assuming clavicular symmetry is unreliable

BACKGROUND

One of the more commonly used methods of determining the amount of shortening of the fractured clavicle is by comparing the length of the fractured side to the length of contralateral unfractured clavicle. A pre-existing natural asymmetry can make quantification of shortening using this method unreliable. The goal of this study is to assess the side-to-side variation in clavicle length in 100 uninjured, skeletally mature adults.

MATERIALS AND METHODS

To assess the side-to-side difference in clavicle length the length of both clavicles of 100 patients on thoracic computed tomography (CT) scans were measured. Patients without a history of pre-CT clavicular injury were included. The measurements were allocated into three groups based on the amount of asymmetry (< 5, ≥ 5-10 and > 10 mm). Dominant side and sex were analyzed to determine influence on the length of the clavicle.

RESULTS

In 30 patients (30%), an asymmetry of 5 mm or more was found. 2% of the patients had a side-to-side difference of more than 10 mm. The absolute side-to-side length difference (LD) was 3.74 mm (95% CI 3.15-4.32; p < 0.001). A significant association between clavicle length and dominant side or sex was found (p < 0.001).

CONCLUSION

These results show that by utilizing a treatment algorithm based upon clavicular symmetry has a potential for error and can lead over- or under-treatment of the fractured clavicle. A significant association between clavicle length and dominant side or sex was found (p < 0.001).

LEVEL OF EVIDENCE

2.

Does regional loss of bone density explain low trauma distal forearm fractures in men (the Mr F study)?

The pathogenesis of low trauma wrist fractures in men is not fully understood. This study found that these men have lower bone mineral density at the forearm itself, as well as the hip and spine, and has shown that forearm bone mineral density is the best predictor of wrist fracture.

INTRODUCTION

Men with distal forearm fractures have reduced bone density at the lumbar spine and hip sites, an increased risk of osteoporosis and a higher incidence of further fractures. The aim of this case-control study was to investigate whether or not there is a regional loss of bone mineral density (BMD) at the forearm between men with and without distal forearm fractures.

METHODS

Sixty-one men with low trauma distal forearm fracture and 59 age-matched bone healthy control subjects were recruited. All subjects underwent a DXA scan of forearm, hip and spine, biochemical investigations, health questionnaires, SF-36v2 and Fracture Risk Assessment Tool (FRAX). The non-fractured arm was investigated in subjects with fracture and both forearms in control subjects.

RESULTS

BMD was significantly lower at the ultradistal forearm in men with fracture compared to control subjects, in both the dominant (mean (SD) 0.386 g/cm² (0.049) versus 0.436 g/cm² (0.054), p < 0.001) and non-dominant arm (mean (SD) 0.387 g/cm² (0.060) versus 0.432 g/cm² (0.061), p = 0.001). Fracture subjects also had a significantly lower BMD at hip and spine sites compared with control subjects. Logistic regression analysis showed that the best predictor of forearm fracture was ultradistal forearm BMD (OR = 0.871 (0.805-0.943), p = 0.001), with the likelihood of fracture decreasing by 12.9% for every 0.01 g/cm² increase in ultradistal forearm BMD.

CONCLUSIONS

Men with low trauma distal forearm fracture have significantly lower regional BMD at the ultradistal forearm, which contributes to an increased forearm fracture risk. They also have generalised reduction in BMD, so that low trauma forearm fractures in men should be considered as indicator fractures for osteoporosis.

Relationship Between Ulnar Variance, Cortical Bone Density, and Load to Failure in the Distal Radius at the Typical Site of Fracture Initiation

PURPOSE

Increased ulnar variance has been shown to lead to diminished load borne by the distal radius. The purpose of this study was to determine the correlations among ulnar variance, bone mineral density, and load to failure at the distal radius.

METHODS

Posteroanterior radiographs and computed tomographic scans were taken of 12 cadaveric forearms in neutral rotation. Ulnar variance was measured for each wrist by the method of perpendiculars. Measurements of cortical, trabecular, and combined bone density were made at the distal radius. We performed linear regression analysis and correlation analysis to determine the relationship between bone densities and ulnar variance measurements. Next, we loaded the 12 cadaveric radii to failure under axial compression. Linear regression analysis and correlation analysis were then performed to determine the relationship between load to failure and both ulnar variance and cortical density.

RESULTS

Increased ulnar variance was significantly correlated with decreased cortical bone density at the distal radius and both were correlated with decreased load to failure. We found no correlation between ulnar variance and trabecular density or combined trabecular and cortical bone density at the distal radius.

CONCLUSIONS

Our study found that increased ulnar variance and decreased cortical bone mineral density correlates with decreased load to failure under axial compression.

CLINICAL RELEVANCE

Ulnar variance is linked to both bone quality and load to failure at the distal radius.

Assessment of anticancer-treatment outcome in patients with metastatic castration-resistant prostate cancer-going beyond PSA and imaging, a systematic literature review

BACKGROUND

In the past years, there has been significant progress in anticancer drug development for patients with metastatic castration-resistant prostate cancer (CRPC). However, the current instruments to assess clinical treatment response have limitations and may not sufficiently reflect patient benefit. Our objective was to systematically identify tools to evaluate both patient benefit and clinical anticancer-treatment response as basis for an international consensus process and development of a specific pragmatic instrument for men with CRPC.

METHODS

PubMed, Embase and CINAHL were searched to identify currently available tools to assess anticancer-treatment benefit, other than standard imaging procedures and prostate-specific antigen measurements, namely quality of life (QoL), detailed pain assessment, physical function and objective measures of other complex cancer-related syndromes in patients with CRPC. Additionally, all CRPC phase III trials published in the last 5 years were reviewed as well as studies using physical function tools in a general cancer population. The PRIMSA statement was followed for the systematic review process.

RESULTS

The search generated 1096 hits, 185 full-text papers were screened and finally 73 publications were included. Additional 89 publications were included by hand-search. We identified a total of 98 tools used in CRPC trials and grouped these into three categories: 22 tools assessing QoL domains and subgroups, 47 tools for pain assessment and 29 tools for objective measures, mainly physical function and assessment of skeletal disease burden.

CONCLUSION

A wide variety of assessment tools and also efforts to standardize and harmonize patient-reported outcomes and pain assessment were identified. However, the specific needs of the increasing CRPC population living longer with their incurable cancer are insufficiently captured and objective physical outcome measures are under-represented. In the age of new anticancer drug targets and principles, new methods to monitor patient relevant outcomes of antineoplastic therapy are of utmost importance.

Clavicular length: the assumption of symmetry

Recent studies have shown subjectively worse outcomes associated with 15 to 20 mm of clavicle shortening. As a result, more than 15 mm of shortening has become a relative indication for operative management. Various methods to quantify shortening have been described in the literature. All measurement techniques described assume clavicular symmetry to assess clavicular shortening. The goal of this study was to assess the side-to-side variation in clavicle length in uninjured, skeletally mature adults.Clavicle length in 102 skeletally mature adults (age range, 22-91 years) was measured using computed tomography data. Clavicle length was defined as the distance between the lateral-most point of the clavicle in the acromioclavicular joint and the medial-most point of the clavicle in the sternoclavicular joint. The side-to-side difference in clavicular length was analyzed, and patients were organized into 2 groups: group 1 was symmetric (difference of less than 5 mm), and group 2 was asymmetric (difference of more than 5 mm). Mean difference in clavicle length for all patients was 4.25±3.8 mm (range, 0-23 mm). Clavicular symmetry was found in 73 (71.5%) of 102 patients. The remaining 29 patients had asymmetry greater than 5 mm. Asymmetry greater than 10 mm was found in 7 (7%) of 102 patients. Twenty-eight percent of clavicles were asymmetric, whereas 7% had clinically significant asymmetry that could affect treatment decisions.This finding calls into question previous methods developed to assess clavicular length in the setting of trauma because of the assumption of symmetry. Further studies are needed to evaluate the effect of hand dominance and pediatric trauma on this observation.

Acute versus chronic exposure to androgen suppression for prostate cancer: impact on the exercise response

PURPOSE

Exercise has been proposed as an effective countermeasure for androgen suppression therapy induced side effects. Since the magnitude of fat gain and muscle loss is most pronounced during the early phases of androgen suppression therapy, the exercise response may differ by the duration of androgen suppression therapy. We investigated whether the exercise response varied by the prior duration of exposure to androgen suppression therapy, that is acute--less than 6 months vs later--6 months or greater.

MATERIALS AND METHODS

A total of 50 men 55 to 84 years old undergoing androgen suppression therapy for nonbone metastatic prostate cancer completed a progressive resistance and cardiovascular exercise program for 12 weeks, including 16 with acute and 34 with chronic androgen suppression therapy exposure. We assessed fat and lean mass by dual energy x-ray absorptiometry as well as muscle strength, functional performance, quality of life and blood biomarkers.

RESULTS

Patients on acute androgen suppression showed an increase in total body fat compared to those on chronic androgen suppression (0.9 kg, p = 0.018). Each group experienced increased appendicular skeletal muscle (about 0.5 kg, p <0.01). Triglycerides decreased in the chronic group and increased in the acute group (p = 0.027). Change in triglycerides were associated with the change in total body fat (r = 0.411, p = 0.004). There were no differences between the groups in prostate specific antigen, testosterone, glucose, insulin, total cholesterol, low and high density lipoprotein, cholesterol, C-reactive protein, homocysteine or quality of life. The 2 groups showed similar improvement in muscle strength and function, and cardiovascular fitness.

CONCLUSIONS

Apart from differences in body fat and triglycerides the beneficial effects of exercise are similar in patients on acute or chronic androgen suppression therapy.

Physiological values and factors affecting the metacarpal bone density of healthy feedlot beef cattle as measured by dual-energy X-ray absorptiometry

The metacarpal bone mineral density of 136 healthy feedlot beef cattle of four different breeds (Charolaise, Limousine, Irish Crossbreed and Slovakian Crossbreed) raised and fed on standard conditions was measured by means of a dual-energy X-ray absorptiometry technique in an ex vivo study design. The average reference values (mean ± SD) of bone mineral density (BMD) for animals aged between 12 and 22 months and weighing between 236 and 546 kg have been reported and the effects of (i) breed, (ii) gender, (iii) age and (iv) body weight on bone mineral density have been considered. A significant difference (i) among different breeds and (ii) between genders resulted, whereas a high correlation between bone density and (iii) age and (iv) body weight was detected within the same breed and gender, with body weight being the most important factor affecting BMD. A modern new technological insight into the study of bovine bone physio-pathology is proposed.

Strength and functional characteristics of men and women 65 years and older

BACKGROUND

Resistance training programs for older adults (>65 years) are an effective method to counteract the loss of muscle mass, strength, and function associated with aging. Nevertheless, limited normative strength and functional data exist for the comparison and stratification of older adults. Therefore, the purpose of this study was to establish normative strength and functional data for males and females 64-69 years, 70-74 years, and 75+ years old, using commonly available equipment and procedures.

METHODS

At total of 110 males and 191 females completed upper and lower body strength and functional performance testing. Measurements were compared across gender and age groups (65-69, 70-74, and 75+ years).

RESULTS

All strength measures, absolute and relative (to body and lean muscle mass), were significantly (p < 0.01) greater in males compared with females. Additionally, younger participants were stronger (p < 0.01) compared with older participants. Similar findings were observed for the functional performance tests. Quartile ranking for relative strength and functional measures provides comparative data for clinical and research assessments.

CONCLUSIONS

This study provides additional normative data for strength and functional performance in males and females aged 65-69, 70-74, and 75+ years and confirms lower performance in females and with aging even when adjusted for lean muscle mass.

Large coronal shear fractures of the capitellum and trochlea treated with headless compression screws

BACKGROUND

The purpose of this study is to retrospectively evaluate the clinical outcomes of 18 patients with large coronal shear fractures of the capitellum and lateral trochlea that underwent open reduction and internal fixation with headless compression screws.

METHODS

Eighteen patients were identified (16 women, 2 men) with an average age of 45 years and an average follow-up of 26 months. Fractures were classified according to the Dubberley classification as 11 type-1A injuries and 7 type-2A injuries.

RESULTS

All patients, with the exception of 1, had good to excellent functional results by the Broberg-Morrey scale (mean score, 93.3). Average arc of motion was 128 degrees in flexion/extension and 176 degrees in pronation/supination. Radiographically, 3 patients had subsequent development of avascular necrosis and 5 developed arthrosis. No significant negative correlation was noted between the development of avascular necrosis and clinical outcome. Minor complications occurred in 2 patients, but there were no re-operations.

CONCLUSION

Headless compression screw fixation allows for stable fixation in patients with large coronal shear fractures of the distal humerus without posterior comminution.

LEVEL OF EVIDENCE

4.

A randomized controlled trial of an exercise intervention targeting cardiovascular and metabolic risk factors for prostate cancer patients from the RADAR trial

Background

Androgen deprivation therapy leads to a number of adverse effects including deterioration of the musculoskeletal system and increased risk factors for cardiovascular and metabolic complications. The purpose of this study is to determine the effects, efficacy, retention and compliance of a physical exercise intervention in a large established cohort of prostate cancer patients from the Randomised Androgen Deprivation and Radiotherapy (RADAR) study. Specifically, we aim to compare short- and long-term effects of a prostate cancer-specific supervised exercise program to a standard public health physical activity strategy utilizing printed resources on cardiovascular and metabolic risk factors. Our primary outcomes are cardiorespiratory capacity, abdominal obesity, and lipid and glycemic control, while secondary outcomes include self-reported physical activity, quality of life and psychological distress.

Methods/Design

Multi-site randomized controlled trial of 370 men from the RADAR study cohort undergoing treatment or previously treated for prostate cancer involving androgen deprivation therapy in the cities of Perth and Newcastle (Australia), and Wellington (New Zealand). Participants will be randomized to (1) supervised resistance/aerobic exercise or (2) printed material comprising general physical activity recommendations. Participants will then undergo progressive training for 6 months. Measurements for primary and secondary endpoints will take place at baseline, 6 months (end of intervention), and at 6 months follow-up.

Discussion

This study uses a large existent cohort of patients and will generate valuable information as to the continuing effects of exercise specifically targeting cardiovascular function and disease risk, insulin metabolism, abdominal obesity, physical function, quality of life and psychological distress. We expect dissemination of the knowledge gained from this project to reduce risk factors for the development of co-morbid diseases commonly associated with androgen deprivation therapy such as cardiovascular disease, obesity, metabolic disease and diabetes, as well as improvements in physical and functional ability, and quality of life.

Trial Registration

ACTRN12609000729224

Combined resistance and aerobic exercise program reverses muscle loss in men undergoing androgen suppression therapy for prostate cancer without bone metastases: a randomized controlled trial

PURPOSE

Androgen suppression therapy (AST) results in musculoskeletal toxicity that reduces physical function and quality of life. This study examined the impact of a combined resistance and aerobic exercise program as a countermeasure to these AST-related toxicities.

PATIENTS AND METHODS

Between 2007 and 2008, 57 patients with prostate cancer undergoing AST (commenced > 2 months prior) were randomly assigned to a program of resistance and aerobic exercise (n = 29) or usual care (n = 28) for 12 weeks. Primary end points were whole body and regional lean mass. Secondary end points were muscle strength and function, cardiorespiratory capacity, blood biomarkers, and quality of life.

RESULTS

Analysis of covariance was used to compare outcomes for groups at 12 weeks adjusted for baseline values and potential confounders. Patients undergoing exercise showed an increase in lean mass compared with usual care (total body, P = .047; upper limb, P < .001; lower limb, P = .019) and similarly better muscle strength (P < .01), 6-meter walk time (P = .024), and 6-meter backward walk time (P = .039). Exercise also improved several aspects of quality of life including general health (P = .022) and reduced fatigue (P = .021) and decreased levels of C-reactive protein (P = .008). There were no adverse events during the testing or exercise intervention program.

CONCLUSION

A relatively brief exposure to exercise significantly improved muscle mass, strength, physical function, and balance in hypogonadal men compared with normal care. The exercise regimen was well tolerated and could be recommended for patients undergoing AST as an effective countermeasure to these common treatment-related adverse effects.

Bone Mineral Density is Not Correlated with One-Year Functional Outcome in Distal Radial Fractures: A Preliminary Study

INTRODUCTION

The intrinsic stability of fractures related to soft tissue injury and the comminution of the metaphyseal part of the distal radius influence the chance of secondary displacement in distal radial fractures treated conservatively. A low bone mineral density may also contribute to this secondary displacement and could therefore play a role in functional outcome. This possible relation between functional outcome and bone mineral density is poorly studied.

PATIENTS AND METHODS

Patients with a unilateral conservatively treated distal radial fracture were assessed one year after their fracture with the DASH score (disabilities of the arm, shoulder and hand) and the Cooney score. Fractures were classified according to the AO classification. Radial inclination, radial shift, radial tilt and ulnar variance were measured on the first and follow-up radiographies. Bone mineral densities of both the hip and lumbar spine were measured by DXA and expressed as T-scores.

RESULTS

Fifty-four patients participated in this study (mean age 68 years). Osteoporosis (T-score ≤ -2.5) was present in 20 patients (37%), osteopenia (T-score of -1 to -2.5) in 30 patients (56%), and normal bone density (T-score > -1) in four patients (7%). The distribution of fracture types according to the AO classification showed 32 A-type fractures, eight B-type fractures and 14 C-type fractures. Both univariate linear and multivariate regression analysis with covariates of age, sex, body mass index and AO classification showed no significant correlation between T-score and functional outcome.

CONCLUSION

The functional outcome of conservatively treated distal radial fractures in this study does not correlate with bone mineral density. Therefore, BMD measurement cannot be used to predict functional outcome in these patients.

[Hormone therapy and anti-aging: is there an indication?]

The desire for a long life is deeply embedded in nearly all men. Fortunately life expectancy has remarkably increased over the past decades, on the other hand advancing age is frequently associated with a rise in morbidity. Above simply prolonging life there is a need to search for strategies to improve the quality of life in the elderly. Different substances to prevent premature aging, cancer and degenerative disorders appear to be promising candidates. Since it has been suggested that the decline of different hormones over the lifespan is closely related to the aging process replacement of these hormones may be a strategy against aging. Especially hormones like growth hormone, DHEA, testosterone and melatonin were considered as anti-aging agents. This review is focusing on the theoretical background and the previously known effects of different hormones to slow aging processes. Despite some promising results in a variety of studies conducted over the past years presently available data do not justify the broad use of hormones for anti-aging purposes. However, although no single hormone can be recognized as a 'rejuvenating' and life extending agent, some of their actions may be beneficial for the aging process.

Enthesis bilateral asymmetry in humans and African apes

Entheses (skeletal muscle and tendon attachment sites) have often been used to infer handedness and activity variability among human populations. However, the specific roles that intensity vs. frequency of muscle contractions play in modifying entheses are not well understood and the assumption that entheses reflect muscle activity levels has been challenged. This study explores the effect of habitual muscular activity on enthesis morphology in humans and African apes by investigating bilateral asymmetry in the forelimbs and hindlimbs of these taxa. Humans have generally more developed entheses in the lower limb while African apes have generally more developed entheses in the forelimbs. All species studied have more asymmetric forelimbs than hindlimbs except humans that show more asymmetrical expression of bony spurs in the lower limbs than in the upper limbs. When comparing species, humans are always more asymmetric in ethesis development than apes for both the forelimbs and hindlimbs, which reflects the relatively greater asymmetry in limb use in humans and the more symmetric use in apes. Enthesis development may reflect cross-symmetry patterns in humans and, more subtly, a moderate handedness in apes during manipulative activities. This study suggests that enthesis morphology provides information on muscle activity levels, with greater development of entheses associated with more habitual or powerful muscle use. The general similarity of ape and human responses to muscle activity suggests that muscle activity influenced enthesis development in Plio-Pleistocene hominins and that interpretation of muscle markings in these fossils can provide data for functional inferences in these extinct species.

Changes in muscle, fat and bone mass after 36 weeks of maximal androgen blockade for prostate cancer

OBJECTIVE

To assess the effects of androgen deprivation therapy (ADT) on whole-body and regional muscle, fat and bone mass in men with prostate cancer without metastatic bone disease.

PATIENTS AND METHODS

Seventy-two men aged 44-88 years underwent spine, hip and whole-body dual-energy X-ray absorptiometry scans at baseline and after 36 weeks of ADT. The change in whole-body and regional lean mass (LM), fat mass (FM), and bone mineral content and density (BMD) were determined. In addition, the prostate specific antigen (PSA), serum testosterone and haemoglobin levels were measured, and the level of physical activity and fatigue assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-30.

RESULTS

The upper limb, lower limb, trunk and whole-body LM decreased by a mean (sem) of 5.6 (0.6)%, 3.7 (0.5)%, 1.4 (0.5)% and 2.4 (0.4)% (P < 0.01), respectively, while FM increased by 20.7 (3.3)%, 18.7 (2.7)%, 12.0 (2.5)% and 13.8 (2.3)% (P < 0.001). Hip, spine, whole-body and upper limb BMD decreased by 1.9 [corrected] (0.3)% [corrected], 3.3 [corrected] (0.4)%, 1.6 [corrected] (0.3)% and 1.3 (0.3%) (P < 0.001), but not lower limb BMD. Serum testosterone, PSA and haemoglobin levels decreased by 93.3 (0.4)%, 98.2 (0.5)%, and 8.8 (0.9)% (P < 0.001), respectively. In addition, physical activity levels decreased and levels of fatigue increased.

CONCLUSION

After 36 weeks of ADT there was a significant decrease in whole-body and regional LM and bone mass, while whole-body and regional FM increased in older men with prostate cancer. Strategies to counteract changes in soft tissue and bone mass during ADT should be formulated to minimize the risk of sarcopenia, osteoporosis and obesity.

Age estimation in the Mediterranean bottlenose dolphin Tursiops truncatus (Montagu 1821) by bone density of the thoracic limb

The determination of age is an important step in defining the life history traits of individuals and populations. Age determination of odontocetes is mainly based on counting annual growth layer groups in the teeth. However, this useful method is always invasive, requiring the cutting of at least one tooth, and sometimes the results are difficult to interpret. Based on the concept that bone matrix is constantly deposited throughout life, we analysed the bone mineral density of the arm and forearm of a series of bottlenose dolphins (Tursiops truncatus, Montagu 1821) stranded along the Italian coast of the Adriatic Sea or maintained in confined waters. The bone mineral density values we obtained were evaluated as possible age predictors of the Mediterranean population of this species, considering age as determined by counting growth layer groups in sections of the teeth and the total body length of the animal as references. Comparisons between left and right flipper showed no difference. Our results show that bone mineral density values of the thoracic limb are indeed reliable age predictors in Tursiops truncatus. Further investigations in additional odontocete species are necessary to provide strong evidence of the reliability of bone mineral density as an indicator of growth and chronological wear and tear in toothed-whales.

Muscle architecture of the common chimpanzee (Pan troglodytes): perspectives for investigating chimpanzee behavior

Thorpe et al. (Am J Phys Anthropol 110:179-199, 1999) quantified chimpanzee (Pan troglodytes) muscle architecture and joint moment arms to determine whether they functionally compensated for structural differences between chimpanzees and humans. They observed enough distinction to conclude that musculoskeletal properties were not compensatory and suggested that chimpanzees and humans do not exhibit dynamically similar movements. These investigators based their assessment on unilateral limb musculatures from three male chimpanzees, of which they called one non-adult representative. Factors such as age, sex, and behavioral lateralization may be responsible for variation in chimpanzee muscle architecture, but this is presently unknown. While the full extent of variation in chimpanzee muscle architecture due to such factors cannot be evaluated with data presently available, the present study expands the chimpanzee dataset and provides a preliminary glimpse of the potential relevance of these factors. Thirty-seven forelimb and 36 hind limb muscles were assessed in two chimpanzee cadavers: one unilaterally (right limbs), and one bilaterally. Mass, fiber length, and physiological cross-sectional area (PCSA) are reported for individual muscles and muscle groups. The musculature of an adult female is more similar in architectural patterns to a young male chimpanzee than to humans, particularly when comparing muscle groups. Age- and sex-related intraspecific differences do not obscure chimpanzee-human interspecific differences. Side asymmetry in one chimpanzee, despite consistent forelimb directional asymmetry, also does not exceed the magnitude of chimpanzee-human differences. Left forelimb muscles, on average, usually had higher masses and longer fiber lengths than right, while right forelimb muscles, on average, usually had greater PCSAs than left. Most muscle groups from the left forelimb exhibited greater masses than right groups, but group asymmetry was significant only for the manual digital muscles. The hind limb exhibited less asymmetry than the forelimb in most comparisons. Examination of additional chimpanzees would clarify the full range of inter- and intra-individual variation.

Muscle strength is a determinant of bone mineral content in the hemiparetic upper extremity: implications for stroke rehabilitation

Individuals with stroke have a high incidence of bone fractures and approximately 30% of these fractures occur in the upper extremity. The high risk of falls and the decline in bone and muscle health make the chronic stroke population particularly prone to upper extremity fractures. This was the first study to investigate the bone mineral content (BMC), bone mineral density (BMD), and soft tissue composition of the upper extremities and their relationship to stroke-related impairments in ambulatory individuals with chronic stroke (onset >1 year). Dual-energy X-ray absorptiometry (DXA) was used to acquire total body scans on 56 (22 women) community-dwelling individuals (>or=50 years of age) with chronic stroke. BMC (g) and BMD (g/cm2), lean mass (g), and fat mass (g) for each arm were derived from the total body scans. The paretic upper extremity was evaluated for muscle strength (hand-held dynamometry), impairment of motor function (Fugl-Meyer motor assessment), spasticity (Modified Ashworth Scale), and amount of use of the paretic arm in daily activities (Motor Activity Log). Results showed that the paretic arm had significantly lower BMC (13.8%, P<0.001), BMD (4.5%, P<0.001), and lean mass (9.0%, P<0.001) but higher fat mass (6.3%, P=0.028) than the non-paretic arm. Multiple regression analysis showed that lean mass in the paretic arm, height, and muscle strength were significant predictors (R2=0.810, P<0.001) of the paretic arm BMC. Height, muscle strength, and gender were significant predictors (R2=0.822, P<0.001) of lean mass in the paretic arm. These results highlight the potential of muscle strengthening to promote bone health of the paretic arm in individuals with chronic stroke.

Low BMD is a risk factor for low-energy Colles' fractures in women before and after menopause

Until now, it was unclear if low volumetric bone mineral density at the distal radius was also a risk factor for Colles' fracture, especially in patients with low-energy trauma. In our study, we used peripheral quantitative computed tomography to measure volumetric bone mineral density of a nonfractured distal radius and dual-energy x ray absorptiometry to measure areal bone mineral density at the spine and hip in patients with Colles' fractures, including 45 women who were premenopausal (age range, 40-50 years) and 39 women who were postmenopausal (age range, 51-65 years). In each group, the patients were subdivided into low-energy and high-energy fracture groups. Ninety-five age-matched healthy women who were premenopausal and 90 age-matched healthy women who were postmenopausal without fracture history served as controls. The results showed that patients with low-energy fractures had a lower bone mineral density at all measurement sites, compared with either patients with high-energy fractures or control subjects. More patients were found with a bone mineral density less than -2.5 standard deviations (Z-score) in the premenopausal group (12.5% measured by dual-energy x ray absorptiometry and 41.2% measured by peripheral quantitative computed tomography) than in the postmenopausal group (6.0% measured by dual-energy x ray absorptiometry and 4.8% measured by peripheral quantitative computed tomography). These results suggest that low bone mineral density, particularly measured using peripheral quantitative computed tomography at the distal radius of women who were premenopausal, was an important risk factor for low-energy Colles' fractures.

LEVEL OF EVIDENCE

Prognostic study, Level I-1 (prospective study). See the Guidelines for Authors for a complete description of levels of evidence.

Vertebral mineral density measured by dual-energy X-ray absorptiometry (DEXA) in a group of healthy Italian boxer dogs

We studied the feasibility of using dual-energy X-ray absorptiometry (DEXA) to obtain reference bone density values in relation to age, gender and body weight in growing and young adult Italian boxer dogs. The study was performed on eight animals (three males and five females) at 7, 12 and 18 months of age. Animals were carefully examined and blood samples were collected from each dog to detect any sign of metabolic and/or endocrine disease. Each subject underwent radiographs to evaluate growth of the spine and hip. One female was not considered in the statistical model because of the development of grade 4 spondylosis deformans during the study period. All animals were serially scanned using DEXA; the region of interest was the whole spine T12-L2, while the subregions of interest were the four vertebrae (T12-T13-L1-L2) within the scanned spine. Statistical analysis was performed separately for each region of interest. Age had the strongest relationship with bone density (P < 0.001). Gender effect on spinal mineral density was not significant while vertebral site effect was highly significant. Average bone mineral density (BMD) +/- SD for the whole spine trait was 0.862 +/- 0.108 g/cm2 while average BMD +/- SD for subregions of interest ranged from 0.836 +/- 0.141 g/cm2 for T12 to 0.928 +/- 0.119 g/cm2 for L2. Estimated reference BMD values at 7, 12 and 18 months of age for each vertebral site in males and females are provided.

Relationship between metabolic bone disease and bone mineral density measured by dual-energy X-ray absorptiometry in the green iguana (Iguana iguana)

The aim of our work was to study the feasibility of using dual-energy X-ray absorptiometry to obtain reference bone density values in relation to body weight, gender, and metabolic bone disease in the green iguana. The study was performed on 28 animals. The weight, age, and gender of each iguana were recorded. Each lizard was carefully examined and radiographed to detect signs of metabolic bone disease. Blood samples were collected from each animal to evaluate Ca/P and total protein. All animals, both affected (group B; n = 11) and unaffected (group A; n = 17) by metabolic bone disease, were individually scanned using an X-ray densitometer. The regions of interest were the head, lumbar spine, right, and left femur. Statistical analysis was performed separately for each region of interest. Body weight had the strongest relationship with bone density (P < 0.01). Within regions of interest, for iguanas of average weight (710 g), statistically significant differences between healthy and sick animals were found: head (0.140 vs. 0.090 g/cm2; P < 0.01); lumbar spine (0.164 vs. 0.107 g/cm2; P < 0.01); right femur (0.103 vs. 0.076 g/cm2; P < 0.01); left femur (0.103 vs. 0.078 g/cm2; P < 0.01). Regression equations to obtain reference values of bone density as a function of body weight for animals affected and not affected by metabolic bone disease are provided. Our data indicate that X-ray bone densitometry is an additional tool for studying bone pathophysiology in reptiles.

Upper-limb bone mineral density of female collegiate gymnasts versus controls

PURPOSE

We examined bilateral bone mineral density (BMD) in the arms of female college gymnasts to assess the relative contribution of high-impact loading forces versus daily activities on bone plasticity.

METHODS

Twenty-five female collegiate gymnasts and 25 controls were studied. BMD of the lumbar spine, proximal femur, and whole body were assessed via dual energy x-ray absorptiometry. Upper-limb BMD was determined by custom analyses of the whole-body scans to examine arms individually.

RESULTS

BMD of gymnasts was significantly (P < 0.0001) greater than controls at all sites. Whole-body BMD was 8% higher in gymnasts (1.270 +/- 0.078 vs 1.175 +/- 0.073 g x cm(-2)), with 18-19% differences in the lumbar spine (1.427 +/- 0.144 vs 1.212 +/- 0.106 g x cm(-2), right proximal femur (1.298 +/- 0.101 vs 1.100 +/- 0.129 g x cm(-2)), and left proximal femur (1.293 +/- 0.111 vs 1.104 +/- 0.133 g x cm(-2)). Arm BMD was 17% greater in gymnasts, with higher values in both dominant (1.013 + 0.067 vs 0.875 + 0.066 g x cm(-2)) and nondominant (1.002 + 0.060 vs 0.849 + 0.062 g x cm(-2)) arms. Intragroup comparisons revealed a significantly (P < 0.0001) greater BMD in the dominant arm of the controls but no side-to-side difference in the arms of the gymnasts.

CONCLUSIONS

Upper-limb BMD followed use patterns in both gymnasts and controls, demonstrating that the forces imposed on the arms with gymnastics training enhanced BMD and resulted in no bilateral differences. These findings illustrate the association between gymnastics training and increased BMD throughout the body, suggesting that the high BMD values observed in gymnasts are due primarily to the activity itself rather than selection bias.

Bone density of the arm and forearm as an age indicator in specimens of stranded striped dolphins (Stenella coeruleoalba)

The age of odontocetes living in the wild is determined mainly by analysis of dentine layers in sections of the teeth. We examined a series of specimens from striped dolphins (Stenella coeruleoalba, Meyen, 1833) that had stranded along the Italian coast of the Mediterranean sea. The present study analyzes and describes bone density in the arm and forearm of the stranded specimens, and correlates the data with total body length of the animal and age as determined by the number of dentine layers in sections of the teeth. According to our model, age can be predicted on the basis of bone density and total body length of the stranded animal. This is the first study to use bone density as a biological parameter to understand the wear and tear of life in the sea. The results suggest that bone density is a new tool for recording age in wild odontocetes.

Lateralized mineral content and density in distal forearm bones in right-handed men and women: relation of structure to function

To test whether handedness has an asymmetric effect on distal forearm bone mineral content (BMC) and bone mineral density (BMD), and whether there is an effect of sex on these variables, the mean BMCs and BMDs in bilateral distal forearms were compared in right-handed men and women. It was expected that the BMC and BMD would be higher on the right than the left side in right-handers. The present results were consistent with this working hypothesis. Namely, the right-BMCs were found to be significantly higher than left-BMCs for all regions of the bones studied. There were no sex differences either for the right-left BMCs or for the right-left BMDs. The results indicated that i) the relation of structure to function would also be valid outside the brain, ii) the mean BMCs, but not BMDs, were significantly higher in the right than the left arm at different distal forearm regions, and iii) there were no significant sex differences in the distal-forearm BMCs and BMDs.

Handedness in past human populations: Skeletal markers

Although it is generally believed that right-handedness has predominated in all human populations since at least the appearance of Homo sapiens sapiens, the evidence has rarely been studied in its entirety. This paper contains a review of the principal skeletal indicators of handedness (cranial and post-cranial), and an introduction to their use to estimate the prevalence of left and right handedness in the past. The role of such reviews is to enable us to assess the testability of genetic models of human handedness and of its evolution, using anthropological and archaeological data.