Global and Spatial Compartmental Interrelationships of Bone Density, Microstructure, Geometry and Biomechanics in the Distal Radius in a Colles' Fracture Study Using HR-pQCT

BACKGROUND

Bone parameters derived from HR-pQCT have been investigated on a parameter-by-parameter basis for different clinical conditions. However, little is known regarding the interrelationships of bone parameters and the spatial distribution of these interrelationships. In this work: 1) we investigate compartmental interrelationships of bone parameters; 2) assess the spatial distribution of interrelationships of bone parameters; and 3) compare interrelationships of bone parameters between postmenopausal women with and without a recent Colles' fracture.

METHODS

Images from the unaffected radius in fracture cases (n=84), and from the non-dominant radius of controls (n=98) were obtained using HR-pQCT. Trabecular voxel-based maps of local bone volume fraction (L.Tb.BV/TV), homogenized volumetric bone mineral density (H.Tb.BMD), homogenized μFEA-derived strain energy density (H.Tb.SED), and homogenized inter-trabecular distances (H.Tb.1/N) were generated; as well as surface-based maps of apparent cortical bone thickness (Surf.app.Ct.Th), porosity-weighted cortical bone thickness (Surf.Ct.SIT), mean cortical BMD (Surf.Ct.BMD), and mean cortical SED (Surf.Ct.SED). Anatomical correspondences across the parametric maps in the study were established via spatial normalization to a common template. Mean values of the parametric maps before spatial normalization were used to assess compartmental Spearman's rank partial correlations of bone parameters (e.g., between H.Tb.BMD and L.Tb.BV/TV or between Surf.Ct.BMD and Surf.app.Ct.Th). Spearman's rank partial correlations were also assessed for each voxel and vertex of the spatially normalized parametric maps, thus generating maps of Spearman's rank partial correlation coefficients. Correlations were performed independently within each group, and compared between groups using the Fisher's Z transformation.

RESULTS

All within-group global trabecular and cortical Spearman's rank partial correlations were significant; and the correlations of H.Tb.BMD-L.Tb.BV/TV, H.Tb.BMD-H.Tb.1/N, L.Tb.BV/TV-H.Tb.1/N, Surf.Ct.BMD-Surf.Ct.SED and Surf.Ct.SIT-Surf.Ct.SED were significantly different between controls and fracture cases. The spatial analyses revealed significant heterogeneous voxel- and surface-based correlation coefficient maps across the distal radius for both groups; and the correlation maps of H.Tb.BMD-L.Tb.BV/TV, H.Tb.BMD-H.Tb.1/N, L.Tb.BV/TV-H.Tb.1/N, H.Tb.1/N-H.Tb.SED and Surf.app.Ct.Th - Surf.Ct.SIT yielded small clusters of significant correlation differences between groups.

DISCUSSION

The heterogeneous spatial distribution of interrelationships of bone parameters assessing density, microstructure, geometry and biomechanics, along with their global and local differences between controls and fracture cases, may help us further understand different bone mechanisms of bone fracture.

Colles' fracture - is it a signal of osteoporosis?

Asymptomatic post-menopausal osteoporosis is common but some-times associated with pain and deformity. Symptomatic osteoporosis is usually associated with fracture. A 59 years old post-menopausal woman presented with a history of acute low-back-pain. She had menopause for 12 years. She gave history of colles' fracture at about two years back. Her mother died as consequences of femoral neck fracture. MRI of vertebral spine showed demineralization with partial collapse of D6,7,12 and L1 vertebra. Dual energy X-ray absorptiometry of vertebra showed BMD T-score of -4.5. Patient was managed with IV infusion of zoledronic acid, oral intake of vitamin D and calcium supplements and with regular non-weight-bearing exercises. Her condition improved gradually. During post-menopausal period, every women must be aware of osteoporosis and any fracture in that time must be evaluated to rule out osteoporosis.

Assessing forearm fracture risk in postmenopausal women

A diverse array of bone density, structure, and strength parameters were significantly associated with distal forearm fractures in postmenopausal women, but most of them were also correlated with femoral neck areal bone mineral density (aBMD), which provides an adequate measure of bone fragility at the wrist for routine clinical purposes.

INTRODUCTION

This study seeks to test the clinical utility of approaches for assessing forearm fracture risk.

METHODS

Among 100 postmenopausal women with a distal forearm fracture (cases) and 105 with no osteoporotic fracture (controls), we measured aBMD and assessed radius volumetric bone mineral density, geometry, and microstructure; ultradistal radius failure load was evaluated in microfinite element (microFE) models.

RESULTS

Fracture cases had inferior bone density, geometry, microstructure, and strength. The most significant determinant of fracture in five categories were bone density (femoral neck aBMD; odds ratio (OR) per standard deviation (SD), 2.0; 95% confidence interval (CI), 1.4-2.8), geometry (cortical thickness; OR, 1.5; 95% CI, 1.1-2.1), microstructure (structure model index (SMI); OR, 0.5; 95% CI, 0.4-0.7), and strength (microFE failure load; OR, 1.8; 95% CI, 1.3-2.5); the factor-of-risk (applied load in a forward fall / microFE failure load) was 15% worse in cases (OR, 1.9; 95% CI, 1.4-2.6). Areas under receiver operating characteristic curves (AUC) ranged from 0.62 to 0.68. The predictors of forearm fracture risk that entered a multivariable model were femoral neck aBMD and SMI (combined AUC, 0.71).

CONCLUSIONS

Detailed bone structure and strength measurements provide insight into forearm fracture pathogenesis, but femoral neck aBMD performs adequately for routine clinical risk assessment.

Rehabilitation after falls and fractures

Falls are one of the most common geriatric problems threatening the independence of older persons. Elderly patients tend to fall more often and have a greater tendency to fracture their bones. Fractures occur particularly in osteoporotic people due to increased bone fragility, resulting in considerable reduction of quality of life, morbidity, and mortality. This article provides information for the rehabilitation of osteoporotic fractures pertaining to the rehabilitation of the fractured patient, based on personal experience and literature. It also outlines a suggested effective and efficient clinical strategy approach for preventing falls in individual patients.

Are osteoporotic fractures being adequately investigated? A questionnaire of GP & orthopaedic surgeons

Background

To investigate the current practice of Orthopaedic Surgeons & General Practitioners (GP) when presented with patients who have a fracture, with possible underlying Osteoporosis.

Methods

Questionnaires were sent to 140 GPs and 140 Orthopaedic Surgeons. The participants were asked their routine clinical practice with regard to investigation of underlying osteoporosis in 3 clinical scenarios.

55 year old lady with a low trauma Colles fracture

60 year old lady with a vertebral wedge fracture

70 year old lady with a low trauma neck of femur fracture.

Results

Most doctors agreed that patients over 50 years old with low trauma fractures required investigation for osteoporosis, however, most surgeons (56%, n = 66) would discharge patients with low trauma Colles fracture without requesting or initiating investigation for osteoporosis. Most GPs (67%, n = 76) would not investigate a similar patient for osteoporosis, unless prompted by the Orthopaedic Surgeon or patient.

More surgeons (71%, n= 83) and GPs (64%, n = 72) would initiate investigations for osteoporosis in a vertebral wedge fracture, but few surgeons (35%, n = 23) would investigate a neck of femur fracture patient after orthopaedic treatment.

Conclusion

Most doctors know that fragility fractures in patients over 50 years old require investigation for Osteoporosis; however, a large population of patients with osteoporotic fractures are not being given the advantages of secondary prevention.

Determinants of incidence of osteoporotic fractures in the female Spanish population older than 50

It is well known that the adoption of preventive measures for osteoporosis may contribute to minimizing its impact as a result of bone fractures. However, there are well-recognized risk factors involved in the onset of osteoporosis that are not possible to modify. Better knowledge of these non-modifiable factors could aid prevention in subjects at high risk of fractures. The aim of this study was to evaluate the likely association between gynecological, reproductive and family history of hip fracture with the incidence of vertebral and nonvertebral osteoporotic fractures in women older than 50. We studied 255 women aged 50 and over, randomly selected from a Spanish population that had participated in a study of prevalence of vertebral fractures (EVOS study). This cohort was prospectively followed for 8 years by means of four postal questionnaires, in order to find out the incidence of nonvertebral fractures. Concerning the incidence of vertebral fractures, participants were invited to repeat the lumbar spine X-rays 4 years after the initial study. A total of 31 women had incident osteoporotic fractures. The analysis of gynecological variables showed that an increase in the age at menarche was a risk factor for all incident osteoporotic fractures [OR=1.57 (1.04-2.37)]. The presence of amenorrhea at any age during the fertile period was associated with higher incidence of all osteoporotic fractures [OR=6.30 (1.61-24.70)]. Among all the reproductive variables analyzed (pregnancy, number of live births and breast-feeding) only pregnancy was an important protective factor in preventing incident Colles fracture [OR=0.15 (0.03-0.62)]. A family history of hip fracture was associated with a higher incidence of all osteoporotic fractures [OR=3.59 (1.01-12.79)]. In summary, a late age at menarche, the presence of amenorrhea and having close relatives with hip fracture were all risk factors which, independently of bone mineral density (BMD) and age, were associated with higher incidence of all osteoporotic fractures. Pregnancy was an important protective factor for the incidence of Colles fractures.

Recognising and treating Colles' type fractures in emergency care settings

In this article, the author explains how to identify a Colles' type fracture, explains how to insert a haematoma block, and gives a step by step guide to reducing this type of fracture.

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.

Postmenopausal women with colles' fracture have lower values of bone mineral density than controls as measured by quantitative ultrasound and densitometry

Measurement of ultrasonographic parameters provides information concerning not only bone density but also bone architecture. We investigated the usefulness of ultrasonographic parameters and bone mineral density (BMD) to evaluate the probability of Colles' fracture. Two-hundred eighty-nine postmenopausal women (62.3 +/- 8.7 yr) with (n = 76) and without (n = 213) Colles' fracture were studied. BMD of lumbar spine and proximal femur was evaluated in all women by dual-energy X-ray absorptiometry (DXA) and speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness in the calcaneus were measured by a Sahara ultrasonometer (Hologic). Patients suffering from Colles' fracture had lower values of BMD adjusted by height at the lumbar spine, L2-L4 (0.797 g/cm2 vs 0.860 g/cm2), femoral neck (0.685 g/cm2 vs 0.712 g/cm2 ), SOS (1518 m/sg vs 1525 m/sg), and stiffness (74.6 vs 77.7) (p < 0.05). Nevertheless, BUA values were similar in both groups. After stepwise logistic regression analysis, the area found under receiver operating characteristic (ROC) curves was 0.60 for L2L4 and 0.63 for a formula combining L2L4 and height. Our data suggest that patients suffering from Colles' fracture have lower values of BMD by DXA, SOS, and stiffness. However, the ability of these techniques to discriminate is low because the values for the area under ROC curve are 0.60 for L2-L4 and 0.63 for a formula derived of the combination of L2-L4 and height.

Risk factors for Colles' fracture in men and women: results from the European Prospective Osteoporosis Study

The aim of this study was to determine the contribution of constitutional and lifestyle variables on the subsequent risk of distal forearm (Colles') fracture in a multinational, multicenter, population-prospective study. A total of 15,745 subjects from the European Vertebral Osteoporosis Study, who had completed a baseline questionnaire on lifestyle and constitutional factors, were followed up annually using a validated questionnaire to ascertain the occurrence of new fractures. Risks are expressed as hazard ratios (with 95% confidence intervals) derived from a Cox proportional hazards regression model. The incidence of Colles' fracture was 1.7 and 7.3 per 1000 person years in men and women, respectively. In women delayed menarche, over the age of 15 years, was associated with a modest increased risk [HR 1.5 (range 1.1-2.0)]. Regular walking in that group also increased the risk [HR 1.6 (1.2-2.2)] perhaps reflecting the increased exposure to risk of falling. None of the other factors examined revealed any important influences. The results are broadly in line with the few other published prospective studies suggesting only a modest role for these factors in influencing susceptibility to fracture.

Peripheral bone mineral density in patients with distal radial fractures

Fractures of the distal forearm are widely regarded as the result of "fragility". We have examined the extent to which patients with Colles' fractures have osteopenia. We measured the bone mineral density (BMD) in the contralateral radius of 235 women presenting with Colles' fractures over a period of two years. While women of all ages had low values for ultra-distal BMD, the values, in age-matched terms, were particularly low among premenopausal women aged less than 45 years. This result was not due to the presence of women with an early menopause. This large survey confirms and extends the findings from earlier small studies. We consider that it is particularly important to investigate young patients with fractures of the distal forearm to identify those with osteoporosis, to seek an underlying cause and to consider treatment.

[Screening for postmenopausal osteoporosis. Women with distal radius fractures should be evaluated for bone density]

In a case-control study at two country hospitals in Sweden, 110 consecutive postmenopausal women (age 50-75) with distal radius fracture were examined with the DXA-technique, on the injured radius, lumbar spine, and the right hip within three weeks after the fracture occurrence. Data was compared with 55 age-matched controls from The Swedish Population Register. The incidence of osteoporosis according to WHO's definition (T-score < -2.5) at any measurement site was higher in the fracture group, 44 per cent compared with 27 per cent in the control group. The fracture group had 12 per cent lower bone mineral density in the distal radius compared with the control group. A higher rate of previous fractures was noted in the fracture group compared with the control group. The study reflects the situation in general health care, where osteoporosis is common in postmenopausal women with distal radius fracture. This patient group can easily be identified and is suitable to be diagnosed for osteoporosis using bone density measurement prior to a decision being reached with regard to any treatment. According to the guideline for medical treatment (T-score < -2.0 and fragile-fracture) as outlined by the Swedish Osteoporosis Society, 75 per cent of postmenopausal patients with forearm fracture should be considered for such treatment.

[Clinical aspects of osteoporosis]

The main clinical presentation of osteoporosis is fracture and its consequences. However a number of diseases and factors can induce bone loss and increase the risk of fracture. Therefore the clinical approach should be initially directed to exclude secondary osteoporosis. Vertebral fractures are the most common osteoporotic fractures; they are characterized by back pain, typical physical changes such as kyphosis and height loss, functional impairment and social decline. On the other hand, hip fracture is the most severe consequence of osteoporosis, because of its higher morbility and mortality. The main pathogenetic determinants of hip fracture are represented by both bone loss and several factors contributing to fall in the elderly. Moreover, a number of conditions are responsible for the high mortality rate following hip fracture. Colles' fracture is rarely hospitalized; however, most patients complain a complex algodystrophic syndrome which impairs the quality of life.

Absolute fracture risk varies with bone densitometry technique used. A theoretical and in vivo study of fracture cases

The lack of consensus of how the results of peripheral bone mineral density (BMD) measurements should be interpreted is proving a barrier to the wider use of these devices. One approach is to interpret peripheral measurements using thresholds (so-called equivalent T-scores) defined to have the same absolute fracture risk as a femoral neck T-score of -2.5. For this concept to be valid, the estimates of fracture risk for a population should be the same irrespective of the measurement technique used. We tested this prediction both theoretically and in vivo using data for 63 postmenopausal women with Colles fracture and 191 control subjects. The theoretical analysis showed that if the normal population has a Gaussian BMD distribution and fracture risk varies exponentially with Z-score as exp(-beta Z) then patients who experience a low-trauma fracture have a fracture risk that is larger by a factor exp(beta(2)) compared with the fracture risk of the whole population. Using data from the in vivo study, fracture risk predictions were compared for seven different types of measurement (lumbar spine; femoral neck; total hip BMD; and speed of sound [SOS] at the radius, tibia, phalanx, and metatarsal). When quantitative estimates of fracture risk were made for individual subjects, the average risk of fracture for the Colles group varied between 1.03 times larger (for tibial SOS) and 2.77 times larger (for total hip BMD) than the average fracture risk for the whole population. As predicted by the theoretical study, fracture risk varied according to the odds ratio determined by logistic regression analysis. Therefore, estimates of fracture risk derived for the same group of patients varied almost threefold according to the type of measurement. It was concluded that equating estimates of absolute fracture risk for different types of scan should not be used as the basis of deriving equivalent T-scores for interpreting peripheral measurements.

[Osteoporosis and Colles' fracture]

We describe the connection between osteoporosis and Colles' fractures of the distal radius from an epidemiological and aetiological point of view. In addition, the value of these fractures as markers of osteoporosis and future risk of fracture is assessed. Several studies have clearly shown an epidemiological association between osteoporosis and fractures of the distal radius, with the association strongest for women up to 65 years of age and for osteoporosis located in the forearm. The association weakens for other locations and for older women. Osteoporosis may have some aetiologic significance for the development of Colles' fractures, but several extraskeletal factors are of equal or further importance. The occurrence of a Colles' fracture in the first 10-15 years after the postmenopause indicates an increased relative risk of sustaining another fracture in the future. However the relative risk approaches one after a few years and, because of the comparatively low absolute risk in this age-group, Colles' fracture as a risk factor contributes little to an assessment of the lifetime fracture risk. In a few longitudinal studies, Colles' fractures could not predict the long-term risk of osteoporosis. The presence of a Colles' fracture should lead to considerations concerning the skeletal and extraskeletal causes of the fracture for the purpose of initiating preventive and therapeutic measures.

Cost effectiveness analysis of BMD referral for DXA using ultrasound as a selective pre-screen in a group of women with low trauma Colles' fractures

Measurements of bone density (BMD) are central to the World Health Organisation (WHO) approach to the definition of osteoporosis. Dual energy X- ray absorptiometry (DXA) remains the gold standard technique for measuring the bone mineral density (BMD) but Quantitative Ultrasound (QUS) is an attractive alternative method of bone assessment because it is easy to use and relatively inexpensive. It has been suggested that QUS could be used as a selective population pre-screen, to maximise the cost effectiveness of referral for DXA assessment of BMD. We set out to examine how such an approach might perform in the assessment of women with low trauma Colles' fracture. In 46 women aged 50-80 (mean 67) years we used DXA to measure BMD at lumbar spine and hip, and heel bone ultrasound to measure Broad Band Attenuation (BUA) and Velocity of Sound (VOS). We calculated local costs of pounds sterling 45 for DXA and pounds sterling 15 for QUS. We identified a BUA threshold of 60 dB/MHz as most cost effective as pre-screen, and calculated a sensitivity of 93% and specificity of 84% in identifying those subjects who were subsequently identified as having osteoporosis by DXA. DXA assessment of all patients had a cost of pounds sterling 77 per osteoporotic subject identified. We examined the cost-effectiveness of using QUS as a pre-screen, only referring subjects for more expensive DXA assessment if BUA was less than 60 dB/MHz. However this approach had no advantage, still costing pounds sterling 78 per osteoporotic subject identified. QUS assessment does not appear cost-effective as a pre-screen for DXA, even in this high risk group of women with low trauma Colles' fracture. A QUS pre-screen would only be cost-effective if the scan could be performed at a substantially lower cost.

Radiostereometric analysis of distal radial fracture displacement during treatment: a randomized study comparing Norian SRS and external fixation in 23 patients

In a randomized study, we included 23 osteoporotic patients with a distal radial fracture and loss of reduction after 1 week. The facture was re-reduced. In one group, a self-setting hydroxyapatite, Norian SRS, was injected into the fracture and the wrist was immobilized for 2 weeks with a dorsal splint (n 12). In the other group, the fracture was immobilized for 5 weeks with an external fixator (n 11). During the operation, the fracture fragments were marked with tantalum markers, so that loss of reduction during the immobilization and after mobilization could be studied with radiostereometric analysis (RSA). We found some recurrence of compression in the fracture in both groups during immobilization. After mobilization, the motion of the fracture, measured by displacement of the fragments along the longitudinal axis, was less than 2 mm, except in 3 cases treated with Norian SRS. A compression along the longitudinal axis of less than 2 mm is not likely to cause any problem in the long term. From the first to the last investigation, 7/12 patients with Norian SRS and 4/11 with external fixation lost more than 2 mm of the reduction along the longitudinal axis. We conclude that 5 weeks of immobilization is sufficient for healing with external fixation in this age group. This immobilization time might be reduced to 2 weeks for fractures treated with Norian SRS, but additional hardware should be used to ensure stability of the fracture system.

Bone density and geometric properties of the distal radius in displaced and undisplaced Colles' fractures: quantitative CT in 70 women

We examined cortical and trabecular bone density and geometric properties of the unfractured distal radius in 70 women with recent Colles' fractures, using multilayer peripheral quantitative computed tomography (pQCT). We found that cortical volumetric density, cortical area and mean cortical thickness were lower in the displaced than in the undisplaced fractures, suggesting that the cross-sectional volumetric density and geometric properties of cortical bone may be essential in determining the severity of a Colles' fracture. We also compared lumbar spine and femoral neck bone mineral density (BMD) and the occurrence of osteoporosis in the displaced and undisplaced fracture groups and found no significant difference, which suggests that displacement of a Colles' fracture is not associated with general osteoporosis.

Bone loss from the hand in women following distal forearm fracture

Bone loss occurs after distal forearm fracture, but it is unclear if this bone loss is fully recovered. We designed a cross-sectional study to evaluate the time course of the bone loss from the hand after distal forearm fracture. We identified 40 women who had a fracture of the distal forearm within the previous 4.5 years. Their ages ranged from 42 to 81 (mean 64 years) and time since fracture 6 to 54 (mean 28 months). These were compared with 95 women (mean age 67, range 57 to 80 years) from a population-based cohort. Lumbar spine (LS) and hand bone mineral density (BMD) were measured in all subjects using a Hologic QDR 1000/W densitometer. Ultrasound of the fingers of both hands was measured in the forearm fracture group using a DBM Sonic 1200 R model. Compared to controls, LS BMD was decreased by 6.4% (p<0.001), non-fractured hand by 3.2% (p<0.001) and the fractured hand by 6.1% (p<0.001) in the forearm fracture group. The mean difference in bone density between the fractured and non-fractured hand was 0.0207 g/cm2, the average value for the non-fractured hand being 0.304 g/cm2. The decement in hand BMD was equivalent to 6.2% (p<0.0001). The difference in hand BMD between the fractured and non-fractured side was greatest when the time since fracture was short; there was no further difference in hand BMD after 2 years. Ultrasound showed a mean difference of 18.7 m/s in amplitude-dependent speed of sound (AD-SoS) with the average value being 1893 m/s. A 1.0% decrease was observed in the fractured hand AD-SoS (p<0.05). A strong relationship was observed between AD-SoS and BMD in both hands (r = 0.70, p<0.001). We conclude that distal forearm fracture results in a significant decrease in hand BMD that is partially reversible. The decrease in hand BMD is reflected in the ultrasound properties of the finger phalanx.

Unmet need in osteoporosis

OBJECTIVE

To audit the management of females presenting to Accident and Emergency department with a diagnosis of low impact Colles fracture.

DESIGN

Telephone questionnaire of 50 patients who attended A & E in 1998 with diagnosis of Colles fracture

SETTING

Glasgow Royal Infirmary within North Glasgow catchment area.

SUBJECTS

Women between 45-79 years of age who attended Accident and Emergency Department in 1998 with a diagnosis of low impact Colles fracture.

RESULTS

Mean age was 63 years (range 44-78): ninety percent were post menopausal and 40% of the total group were smokers. Twenty six percent had a positive family history of osteoporosis, 24% had undergone hysterectomy and 88% took no part in any load bearing exercise. Ten percent (n = 5) were on treatment (1 alendronate, 3 etidronate with calcium, 1 hormone replacement therapy)

CONCLUSION

A significant proportion of our study population have multiple risk factors for osteoporosis which are not being addressed. Raising awareness in orthopaedic surgeons, family doctors and patients is urgently required.

The effect of alendronate on bone mass after distal forearm fracture

Fracture and immobilization of an extremity lead to bone loss at the fracture and at adjacent sites. We conducted a 1-year, single-center, prospective, randomized, double-blind study to determine whether bone loss would occur in the distal radius after a Colles' fracture and whether this loss could be prevented using an antiresorptive drug (alendronate). Thirty-seven women with a recent fracture of the distal forearm and low bone mineral density (BMD) of the lumbar spine were randomized to receive either 10 mg alendronate daily or placebo. BMD of both forearms was measured at baseline and after 3, 6, and 12 months. The results of four women who developed reflex sympathetic dystrophy were not included in the analysis. In the placebo group, there was a significant reduction at 3 months and 6 months in BMD of total radius (p < 0.01), one-third distal radius (p < 0.01), middistal radius (p < 0.05), and ultradistal radius (p < 0.01) on the fractured side. The loss in BMD at one-third distal radius remained significant at month 12 (p < or = 0.001). In the alendronate group BMD of total distal radius, one-third distal radius, and middistal radius at the fractured side remained unchanged. BMD of ultradistal radius increased significantly at months 3, 6, and 12, compared with baseline (p < 0.05). The difference between the two treatment groups was significant at 3 months and 6 months and borderline significant (p = 0.054) after 1 year in total distal radius. In ultradistal radius the differences were significant at all time points. We conclude that BMD of the distal radius of a recently fractured forearm decreases significantly in the 6 months after fracture and the resulting deficit remains evident at least 1 year after fracture. This bone loss can be prevented by alendronate.

[Diagnosis and treatment of postmenopausal osteoporosis after a Colles' fracture]

OBJECTIVES

To investigate whether the presence of Colles fracture leads to diagnostic studies or treatment of osteoporosis in postmenopausal women.

DESIGN

Retrospective study with follow-up of incident cases.

SETTING

Hospital General de Vic and Primary Care Centre Osona. Vic. Barcelona.

PARTICIPANTS AND METHODS

We studied 80 postmenopausal women with Colles' fracture during 1995-1996. The clinical records were systematically reviewed and treatment with antiosteoporotic drugs before and after Colles' fracture were compared.

MEASUREMENTS AND MAIN RESULTS

Diagnostic studies were found in 3 (3.8%) patients. 6 patients (7.5%) took antiosteoporotic drugs before the fracture while 21 (26.3%, p < 0.001) did so after it.

CONCLUSIONS

A recent Colles' fracture induces few osteoporosis diagnostic studies. However, it leads to a significant increase in the use of antiosteoporotic drugs.

Fractures of the distal forearm in young adults. An epidemiologic description of 341 patients

We describe the epidemiology of all distal radial fractures in young adults (men 20-59 years, women 20-49 years) in Lund (1992-95) and Malmö (1994-95), Sweden. During the study period, there were 341 patients with 346 fractures in the two cities, found through the Hospital Register of Diagnoses in Lund and the register of the Radiology Department in Malmö. More than half of the fractures were dislocated and 2/3 of the cases involved the radiocarpal or radioulnar joints, in contrast to the predominantly extra-articular fractures in the elderly. There was an even distribution between sexes and the fractures were mainly caused by a severe trauma, i.e., more than a simple fall, most often sports injuries in January, February and May. Our findings suggest that distal radial fractures in nonosteoporotic young adults should be regarded as a special entity, at least in epidemiological studies. Possibly they also require treatment differing from that for osteoporotic fractures.

Changes in bone mass and bone turnover following distal forearm fracture

Bone loss occurs close to a fracture and is associated with increased bone turnover. Fracture healing itself results in increased markers of bone turnover. But the exact patterns of these changes after different fractures are unclear. We aimed to investigate the changes in bone density and biochemical markers following distal forearm fracture. Twenty women (mean age 63 years) were recruited following fracture of the distal radius and ulna. Bone mineral density (BMD) of the hand and forearm were measured by dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) of the fingers was measured at 0, 6, 12, 26 and 52 weeks after fracture. Serum and urine samples were collected at 0, 3 and 7 days and at 2, 4, 6, 12, 26 and 52 weeks after fracture to measure markers of bone turnover. For bone formation we measured: bone alkaline phosphatase (iBAP), osteocalcin (Oc), procollagen type I N-terminal propeptide (PINP); and for bone resorption: tartrate-resistant acid phosphatase (TRAcP), free deoxypyridinoline (iFDpd), N-telopeptides of type I collagen (NTx). We used the nonfractured limb to calculate values for baseline BMD and amplitude-dependent speed of sound (AD-SoS). There was a decrease in BMD at the hand and in AD-SoS of the fingers after forearm fracture (p<0.001). This bone loss was maximal for BMD by 6 weeks at 9% (p<0. 001) and remained decreased at 52 weeks. AD-SoS decreased at 12 weeks by 3% (p<0.01) and recovered completely by 52 weeks. Bone formation markers increased between 2 and 4 weeks by 13-52% (p<0. 001), and were still elevated at 52 weeks. Bone resorption markers increased between 2 and 6 weeks by 18-35% and returned to baseline at 52 weeks (TRAcP remained elevated). We conclude that BMD decreased distal and immediately proximal to the fracture line when measured with DXA and QUS. Bone loss after distal forearm fracture did not recover by 52 weeks and most bone turnover markers did not return to baseline.

[Fractures following accidental falls among the elderly in the county of Aarhus]

The incidence rates of common fall-related fractures were investigated in a Danish population of elderly people (> 64 years). One thousand one hundred and eighty fractures in 1016 patients were observed. About 26/1000 suffered a fracture per year, 47% being hip fractures, and 33% fractures of the wrist. Incidence rates increased with age, most markedly for fractures in the weight-bearing skeleton (hip, pelvis and vertebral column). Patients with a fall-related fracture had a four times higher risk of getting a new fracture. Increased mortality, adjusted for age and sex, ranged from 10 to 30 percent in the first year; except for fractures of the wrist, which were not associated with increased mortality.

Airbag-induced fracture in a patient with osteoporosis

Since the introduction of automotive airbag technology, patterns of airbag-induced injuries have emerged. Various types of upper-extremity trauma including fractures have been described. Previous reports have focused on the location of the forearm before deployment as the major determinant of fracture. We describe a case of forearm fracture resulting from an airbag deployment in a lupus patient with documented osteoporosis. Bone strength has recently been determined in laboratory testing to be an important factor determining airbag-induced fracture risk. An airbag-induced forearm fracture in an otherwise healthy individual may be an indicator of reduced bone strength.

Management of Colles' fractures

The Colles' fracture is probably the most common fracture seen in the Emergency Department. Although there are several different methods of reduction and fixation, the goal of any treatment plan is to return the patient to normal function. Depending on the complexity, the Colles' fracture can be successfully treated open or closed. This article reviews the mechanism of injury, assessment, conservative or operative treatment, and rehabilitation of these fractures.

Colles' fracture of the wrist as an indicator of underlying osteoporosis in postmenopausal women: a prospective study of bone mineral density and bone turnover rate

Colles' fracture has been shown to be associated with an increased risk of hip fracture. The incidence of low bone mineral density (BMD) and high bone turnover in such patients is uncertain. The aim of this study was to prospectively assess BMD and bone turnover in a cohort of consecutive postmenopausal Colles' fracture patients. BMD (spine, hip and contralateral radius) was measured by dual-energy X-ray absorptiometry (DXA) within 2 weeks of fracture. Bone turnover was assessed within 4 days by measurement of serum osteocalcin, total alkaline phosphatase (TALP), bone-specific alkaline phosphatase (BSAP) and urine hydroxyproline. We recruited 106 (71%) of 149 consecutive patients. Fifty-one per cent of subjects had a history of previous fracture, and 25% a past history of wrist, hip or vertebral body fracture. The incidence of osteoporosis was 21%, 42% and 22% at the spine, hip and radius respectively. Fifty per cent of subjects had osteoporosis of at least one of these sites. When compared with the values expected for their age the patients were found to have higher BMD than expected at the spine, and slightly lower BMD at the hip and distal radius. Patients aged 65 years or less had lower hip BMD than expected from the age-matched normal range (p < 0.01). Osteocalcin and TALP levels did not differ from the normal ranges, but BSAP and hydroxyproline levels were significantly elevated (p < 0.001), with 37% and 25% of patients having levels above the respective normal ranges. We conclude that osteoporosis is common in patients with Colles' fracture; however, in older patients BMD is not lower than would be expected in the normal population. In patients aged 65 years or less BMD is lower than expected at the hip. Bone turnover rate is high in many such patients. Intervention to prevent future fracture would be appropriate in women aged 65 years or less with Colles' fracture.

K-wire fixation for redislocated Colles' fractures. Malunion in 8/21 cases

One therapeutic alternative for redislocation of Colles' fractures is closed reduction and transstyloid Kirschner-wire fixation. We describe our results concerning 21 redislocations treated in this way. According to Older's classification, B fractures were type 3 and 13 fractures type 4. After a median follow-up period of 2 years, most patients had regained normal volar tilt, but significant loss of radial tilt and radial length was found in 11 patients. Malunion occurred in 8 wrists due to either fracture comminution or insufficient K-wire fixation. According to Gartland and Werley's point system, the end-results were poor in 2, fair in 11, good in 4, and excellent in 4 wrists. There was no statistically significant difference in secondary displacement and functional end-result between Older's type 3 and type 4 fractures. We conclude that K-wire fixation is frequently not firm enough and external fixation might be a better alternative for stabilizing redislocated distal radial fractures.

[Colles' fracture in a girl after fulguration]

In the present study we describe the case of a 11 years old child, female, who was accidentally fulgurated by the left arm and after has presented an episode of pallor, shaking, confusion, throbbing and tingle of the arms. For this reason she was admitted in our Department of Pediatrics, University of Rome "La Sapienza". The child presented also a moderate pain at the left wrist. For this reason was performed a wrist X Ray which showed an incomplete fracture of the distal extremity of the radial diaphysis, with a small ulnar infraction of the same side. Life parameters and the ECG were normal so as the blood exams, in particular the CPK and the LDH (in fact, they can be indication of muscular necrosis). In summary the Authors with this study would like to remark the necessity of to suspect a fracture in the place of admittance of the electric current, even if not immediately appear clean signs of oedema, pain and functional impotence.

The relationship between osteoarthritis of the hands, bone mineral density, and osteoporotic fractures in elderly women

To study the relationship between osteoarthritis (OA) and osteoporosis (OP), radiographic osteoarthritis lesions of the hands (HOA) were quantified in 300 healthy women, aged 75 years or more, as a subgroup of a cohort originally recruited for a multi-centre study of risk factors for femoral neck fracture. The HOA combined score (i.e. the sum of the grades of joint-space narrowing, osteophytes, erosions and joint misalignment), the osteophytosis score and the joint-space narrowing score were calculated on a radiograph of both hands. Bone mineral density (BMD) was measured using dual-energy X-ray absortiometry (Lunar DPX) at the femoral neck, Ward's triangle and the total body. BMDs of the total spine, lumbar spine, and the upper and lower limbs were derived from the regional analyses of the total body measurement. Correlations between bone mass, HOA scores and other variables were explored by multiple linear regression and stepwise logistic regression analysis. The HOA combined score was positively correlated with increasing age but not with body mass index. In the multiple regression analyses the HOA combined score positively correlated with BMD and the joint-space narrowing score. According to stepwise logistic regression and after off adjustment of BMD for age, women with an HOA combined score higher than 20 had significantly higher BMD values at all skeletal sites. Sixty-nine women (23%) reported a history of osteoporotic fracture; among them, 20 (6.6%) reported a history of vertebral fracture. The OA score of both subgroups was significantly lower than that of women with no history of fracture. These data suggest that in elderly women the severity of HOA is positively correlated with bone mass and that women with a higher score of HOA more rarely report a history of osteoporotic fracture.

Risk factors for fractures of the distal forearm: a population-based case-control study

To evaluate the risk factors for early osteoporosis in consecutive patients with fracture of the distal forearm, a population-based case-control study was carried out using postal questionnaires supplemented by interviews when necessary. All men and women between the ages of 40 and 80 years who were resident in the County of Uppsala (population 265,000) and who sustained a fracture of the distal forearm during a defined 12-month period were initially included. Of 427 cases, 385 (90.2%) replied. Those with previous fragility fractures were excluded, leaving 367 patients in the study (mean age 61.9 +/- 10.6 years): 302 women (mean age 62.8 +/- 10.1 years) and 65 men (mean age 57.5 +/- 11.8 years). For each patient an age- and sex-matched control without previous fragility fractures was selected from the population register. The questionnaire concerned heredity, diseases and medications, general health, tobacco smoking and physical activity. Reproductive variables and postmenopausal hormone replacement therapy were analyzed extensively. In neither sex were any significant, consistent differences found with regard to chronic diseases, medications, physical activity or smoking. In females heredity for fractures (odds ratio, OR = 1.46) was associated with an increased risk. Nulliparous women had an increased risk of forearm fractures (OR = 1.72) while late menopause (OR = 0.95) and postmenopausal oestrogen therapy > 2 years (OR = 0.44) appeared to be protective. It is concluded that lifestyle factors did not discriminate between fracture patients and controls in this strict population-based investigation, suggesting that in affluent Western societies, with their high fracture rate, most individuals have an osteoporosis-prone way of life.(ABSTRACT TRUNCATED AT 250 WORDS)

Distal radius fracture is an early sign of general osteoporosis: bone mass measurements in a population-based study

To evaluate the bone mass by bone density measurements in patients with distal radius fracture, a prospective open case-control study was carried out in the county of Uppsala, Sweden, with population-based cases and controls. There were 111 patients with a distal radius fracture who were otherwise healthy and aged 53-76 years, together with 60 healthy controls of similar age, sex and menopausal status. The main outcome measures were bone mineral density (BMD) in the lumbar spine and hip measured with dual-energy X-ray absorptiometry, and in the (non-fractured) distal forearm determined by single-photon absorptiometry. It was found that at all measuring sites BMD was significantly lower in cases than in controls. The difference in the distal forearm was around 20% (p < 0.001) and in the spine and hip 5%-8% (p < 0.05-0.001). In the healthy subjects there were positive correlations (r = 0.39-0.65; p < 0.002) between the forearm BMD and that of both the spine and hip, whereas in the patients with distal radius fracture there was only a weak correlation between the forearm and spine BMD (r = 0.28; p < 0.05) and no association between the BMD of the forearm and hip (r < 0.01). It is concluded that patients with distal radius fracture who are otherwise healthy have a preferential bone loss at the distal forearm but also a generally low bone mass. Patients with fracture of the distal radius fracture should be considered for prophylactic measures against osteoporosis.

Age and sex influences on fall characteristics

OBJECTIVE

To investigate age and sex influences on fall characteristics.

METHODS

A total of 1243 subjects (517 males and 726 females) aged 50 years and over and drawn from population based sampling frames were invited to complete an interviewer administered questionnaire concerning descriptive characteristics of falls experienced in the previous four months. Information collected included details about the part of the body to strike the ground, direction of the fall, level of trauma and whether or not injury or fracture was sustained.

RESULTS

One hundred and seventy two subjects reported a fall in the previous four months. Restricting analysis to the 142 subjects who fell from a standing height or less, females aged 50-64 years were more than twice as likely to fall onto their hand compared with older females (odds ratio (OR) = 2.2; 95% confidence interval (CI) 0.8 to 6.2) and at all ages (50+) were more than three times as likely to fall on their hip compared with males (OR = 3.4; 95% CI 1.0 to 11.5). Compared with older males, males aged 50-64 were more likely to fall sideways (OR = 5.1; 95% CI 1.5 to 17.4) and less likely to fall forwards (OR = 0.4; 95% CI 0.1 to 1.1).

CONCLUSION

There is a potentially clinically important variation in fall type by age and sex. In particular, this variation might explain patterns of occurrence of hip and Colles' fracture.

Assessment of fracture risk and its application to screening for postmenopausal osteoporosis: synopsis of a WHO report. WHO Study Group

The criteria required for an effective screening strategy for osteoporosis are largely met in Caucasian women. The disease is common and readily diagnosed by the measurement of bone mineral with single- or dual-energy absorptiometry. Such measurements have high specificity but lower sensitivity, so that the value of the technique is greater for those identified as being at higher risk. Against this background there is little evidence that osteoporosis can usefully be tackled by a public health policy to influence risk factors such as smoking, exercise and nutrition. This suggests that it is appropriate to consider targetting of treatment with agents affecting bone metabolism to susceptible individuals. Since the main benefits of the use of hormone replacement therapy (HRT) are probably on cardiovascular morbidity, the major role for selective screening is to direct non-HRT interventions. An appropriate time to consider screening and intervention is at the menopause, but screening at later ages is also worthy of consideration. Since the cost of screening is low and that of bone-active drugs is high, the selective use of screening techniques will improve the cost-benefit ratio of intervention.

Hip and distal arm fracture rates in peri- and postmenopausal insulin-treated diabetic females

OBJECTIVES

Hip and distal arm fractures are associated with osteoporosis in the postmenopausal female. In diabetic patients, bone mass has been found to be reduced leading to the hypothesis that diabetes is a risk factor for osteoporosis. Whether this has any clinical implication has only been sparsely elucidated.

DESIGN

A cross-sectional case-control study.

SETTING

All insulin-treated diabetic females above the age of 40 years who regularly visited the Steno Memorial Hospital out-patient clinic in 1989. Peri-and postmenopausal females from the general population living in a similar suburban region of Copenhagen admitted to Glostrup University Hospital because of a hip or Colles' fracture between 1 January 1989 and 31 October 1990.

SUBJECTS

The study comprised 748 insulin-treated diabetic females. Thirty hip fractures and 82 Colles' fractures were reported after the age of 40 years. Out of 26,564 females from the general population, 622 were admitted to Glostrup hospital because of a hip or Colles' fracture. METHODS/INTERVENTION: Answers based on questionnaires sent to all diabetic females, and the use of hospital files and hospital registers.

RESULTS

In diabetic females aged 40-49 years, Colles' fracture rate was 2/1000 years and hip fracture rate 0.43/1000 years. Fracture rate increased with age and, amongst 80-89-year-old diabetic females, the frequency of both fracture rates was 31/1000 years. These rates were slightly lower than the rates in the general female population. The relative risk of Colles' fracture in diabetic females aged 40-49 years was 0.3 +/- 0.2 (95% confidence limits) and that of hip fracture 1.0 +/- 1.1. In diabetic females aged 80-89 years, the risk of Colles' fracture and hip fracture were 1.3 +/- 1.1 and 1.0 +/- 0.9. Fracture rate was not associated with the development of diabetic complications, long-term metabolic control, or age at diagnosis.

CONCLUSION

Our results suggest that diabetic osteopenia does not have any clinical impact on fracture risk.

The epidemiology of fragility fractures: is there a role for bone quality?

Fragility fractures, particularly those of the hip, vertebrae, and distal forearm, constitute a major public health problem. The two ultimate determinants of fracture are bone strength and propensity to trauma. Bone strength depends not only upon bone mass but also upon a variety of qualitative aspects of bone structure. These include its architecture, the amount of fatigue damage it has sustained, and changes in its bulk material properties, indices that are collectively subsumed into the term "bone quality." Fragility fractures show differences in their patterns of incidence by age, sex, ethnic group, geographic area, and season. Many of these differences are currently unexplained, and disorders of bone quality might contribute to them. There are two fracture sites at which evidence implicates bone quality more directly--the spine and proximal femur. Many vertebral compression fractures follow minimal trauma, and controlled studies suggest that vertebral microarchitecture contributes to fracture risk independently of vertebral bone mass. At the hip, observational studies have pointed to a role for disordered trabecular architecture, accumulation of microfractures (fatigue damage), and the accumulation of osteoid. The extent to which these phenomena act independently of bone mass, however, remains uncertain.

Colles' fracture associated with reduced bone mineral content. Photon densitometry in 74 patients with matched controls

In a prospective population-based investigation, we measured bone mineral density (BMD) of the forearm using single-photon absorptiometry at both a distal and a more proximal site in 74 Colles'-fracture patients who were compared with controls matched for age, sex, and years after menopause. For both groups there was a marked inverse relationship between age and bone mass. However, over the entire age range, the probands had 11 percent reduced BMD when compared with the controls. Our findings confirm that patients with fracture of the distal forearm have reduced BMD. They constitute an appropriate group for studies aimed at prevention of fracture in the elderly.

[A study of risk factor in osteoporosis, femoral neck fracture and colles' fracture]

This work studied risk factors of osteoporosis, femoral neck fracture and Colles' fracture. The results were compared with those of a healthy group. Milk intake was frequent in the healthy group, but rare in the femoral neck fracture or Colles' fracture group. Most of osteoporosis and femoral neck fracture group were bed ridden, or stayed indoors for a long time before injury. They weighed less and were thin as compared to the healthy group. Decrease of activities of daily living and less body weight were risk factors of osteoporosis and femoral neck fracture, but these risk factors were more predominant in the femoral neck fracture than osteoporosis group. In this study, 74.4% of the patients with femoral neck fracture also had osteoporosis and 33.3% with Colles' fracture had osteoporosis. Colles' fracture was related to injury force and femoral neck fracture was found to be closely related to osteoporosis.

A model of lifetime osteoporosis impact

The study goal was to use population-based data to model aspects of lifetime osteoporosis impact not previously studied, specifically: (1) to estimate person-years of fracture-related functional impairment against the trajectory of functional status in the general population; (2) jointly to consider hip, vertebral, and Colles' fractures in estimating the percent of women who will ever fracture; and (3) to estimate the lifetime number of fractures expected in a cohort of 10,000 50-year-old white postmenopausal women. The model estimates that 54% of 50-year-old women will sustain osteoporosis-related fractures during their remaining lifetimes. Beyond the functional impairment expected in similarly aged, unfractured women, osteoporosis-related fractures are estimated to cause 6.7% of women to become dependent in basic activities of daily living; 7.8% are expected to require nursing home care for an average of 7.6 years.

Factors associated with Colles' fracture in the elderly

We have measured sway, hearing and eyesight in a group of elderly patients with Colles' fracture (3 males, 21 females, mean age 75.9 years) and in a control group of elderly fallers (5 males, 19 females, mean age 76.9 years) who had no fractures. The Colles' fracture group had better eyesight than the control group (p = 0.022), but worse hearing, particularly at lower frequencies (p less than 0.0001 at 500 Hz), suggesting a conductive hearing loss. We conclude that those individuals with better eyesight would try to stretch their arm to break a fall, so breaking their wrist. Osteoporotic changes in the auditory ossicles is proposed as a possible cause for the hearing loss in the Colles' fracture group. We conclude that those individuals presenting with Colles' fracture may also have hearing loss and conversely, patients presenting with a conductive hearing loss may be at risk of developing the further symptoms of osteoporosis.