Chronic effects of stroke on hip bone density and tibial morphology: a longitudinal study

Association between bone mineral density and stroke: a meta-analysis

Objective

The correlation between bone mineral density (BMD) and stroke remains inconsistent. This study aims to determine whether a reduction in BMD is associated with an increased risk of stroke.

Methods

We systematically searched Medline, Embase, and the Cochrane Database of Systematic Reviews through January 2025 to identify cohort studies with follow-up that reported the influence of a reduction in BMD or low BMD status on the risk of any type of stroke. Pooled analyses were performed using random-effects models.

Results

This study included 13 studies with 146,758 individuals. A 1 SD reduction in BMD was associated with an increased risk of stroke (eight studies; RR, 1.24; 95% CI, 1.09-1.40; p < 0.001; I2 = 87%). Subgroup analysis showed that a per SD reduction in BMD was associated with incident stroke in female persons (eight studies; RR, 1.28; 95% CI, 1.09-1.51; p = 0.002; I2 = 87%), but not in male persons (four studies; RR, 1.04; 95% CI, 0.99-1.10; p = 0.15; I2 = 0%). People with osteoporosis or osteopenia had an increased risk of incident stroke (six studies; RR, 1.59; 95% CI, 1.22-2.08; p < 0.001; I2 = 92%), as well as male persons (two studies; RR, 3.16; 95% CI, 1.96-5.12; p < 0.001; I2 = 35%). Sensitivity analysis showed that the results were stable.

Conclusion

Reduction in BMD is associated with a significantly increased risk of stroke. Female individuals have a higher risk than male persons.

Clinical Characteristics and Bone Mineral Density Score in Post-Stroke Neuromuscular Deficit

Background

Disuse osteoporosis in hemiparetic patients often results in significant morbidity, decreased quality of life, and different clinical characteristics. The study aimed to investigate the effect of these clinical factors on bone mineral density (BMD).

Methods

This was an analytical observational study with a cross-sectional method evaluating hemiparetic patients at Cipto Mangunkusumo Hospital from 2018 to 2019. BMD (g/cm2) was assessed using dual energy X-ray absorptiometry (DXA) on the spine and both sides of the body. The relationship and correlation between BMD and delta BMD scores with clinical characteristics were analyzed. A linear regression test was used to assess the correlation between variables.

Results

A total of 34 participants were recruited for this study. There was a difference between the healthy and paretic side of BMD of both hip and wrist (P < 0.001), strong positive correlation between the onset of hemiparesis and wrist and hip delta BMD (r = 0.779, P = 0.001 and r = 0.791, P = 0.001), and significant association between delta BMD and age and motor strength. Multivariate analysis shows that the onset of hemiparesis was a strong predictor of delta BMD (aR2 wrist = 0.486, aR2 hip = 0.614). There was a 7.36% decrease in the mean BMD score of the paretic side compared to the non-paretic side.

Conclusion

A low BMD score is prevalent in seven out of 10 patients with post-stroke neuromuscular deficit. Age, limb strength, the onset of hemiparesis, and rehabilitation compliance are associated with decreased BMD among patients with post-stroke neuromuscular deficit.

Non-pharmacological and pharmacological treatments for bone health after stroke: Systematic review with meta-analysis

BACKGROUND

Hemi-osteoporosis is a common secondary complication of stroke. No systematic reviews of pharmacological and non-pharmacological agents for post-stroke bone health have estimated the magnitude and precision of effect sizes to guide better clinical practice.

OBJECTIVES

To examine the benefits and harms of pharmacological and non-pharmacological agents on bone health in post-stroke individuals.

METHODS

Eight databases were searched (PubMed, Cochrane library, Scopus, CINAHL Complete, Embase, PEDro, Clinicaltrils.gov and ICTRP) up to June 2023. Any controlled studies that applied physical exercise, supplements, or medications and measured bone-related outcomes in people with stroke were included. PEDro and the GRADE approach were used to examine the methodological quality of included articles and quality of evidence for outcomes. Effect sizes were calculated as standardized mean differences (SMD) and risk ratio (RR). Review Manager 5.4 was used for data synthetization.

RESULTS

Twenty-four articles from 21 trials involving 22,500 participants (3,827 in 11 non-pharmacological and 18,673 in 10 pharmacological trials) were included. Eight trials were included in the meta-analysis. The methodological quality of half of the included non-pharmacological studies was either poor or fair, whereas it was good to excellent in 8 of 10 pharmacological studies. Meta-analysis revealed a beneficial effect of exercise on the bone mineral density (BMD) of the paretic hip (SMD: 0.50, 95 % CI: 0.16; 0.85; low-quality evidence). The effects of anti-resorptive medications on the BMD of the paretic hip were mixed and thus inconclusive (low-quality evidence). High-quality evidence showed that the administration of antidepressants increased the risk of fracture (RR: 2.36, 95 % CI 1.64-3.39).

CONCLUSION

Exercise under supervision may be beneficial for hip bone health in post-stroke individuals. The effect of anti-resorptive medications on hip BMD is uncertain. The adverse effects of antidepressants on fracture risk among post-stroke individuals warrant further attention. Further high-quality studies are required to better understand this issue.

REGISTRATION

PROSPERO CRD42022359186.

The effect of stroke on the bone mineral density: A systematic review and meta-analysis

OBJECTIVES

Stroke survivors frequently encounter physical complications. This study aimed to evaluate the impact of stroke on bone mineral density (BMD) and assess the risk of post-stroke osteoporosis or osteoporotic fractures.

DESIGN

Systematic review and meta-analysis.

SETTING AND PARTICIPANTS

We systematically searched Medline, Embase, and the Cochrane Database of Systematic Reviews to identify longitudinal studies reporting the influence of stroke on BMD, osteoporosis, and osteoporotic fractures. Pooled analyses were performed utilizing random-effects models.

RESULTS

This study included 21 studies with 1,029,742 participants. The mean difference of BMD in the paretic femoral neck between follow-up and initial measurements was -0.07 g/cm2 (95% CI, -0.09 to -0.04), and -0.03 g/cm2 (95% CI, -0.05 to -0.01) in the non-paretic femoral neck. A follow-up length exceeding six months was associated with a more pronounced decrease compared to a follow-up of under six months (MD, -0.08; 95% CI, -0.11 to -0.05 vs MD, -0.04; 95% CI, -0.06 to -0.02; P =  0.03). No significant change in lumbar spine BMD was detected post-stroke (MD, -0.00; 95% CI, -0.03 to 0.02), nor was significant change observed in the non-paretic distal radius, proximal humerus, tibia, trochanter, and total hip. Stroke was not associated with an increased risk of osteoporosis or osteoporotic fractures (HR, 1.43; 95% CI, 0.95-2.13).

CONCLUSION

Stroke survivors undergo significant BMD loss in paralyzed limbs, most notably in the femoral neck. However, BMD in the lumbar spine does not exhibit a significant decrease post-stroke. The risk of post-stroke osteoporosis or osteoporotic fractures should be interpreted with caution and needs further investigation.

Brazilian Academy of Neurology practice guidelines for stroke rehabilitation: part I

The Guidelines for Stroke Rehabilitation are the result of a joint effort by the Scientific Department of Neurological Rehabilitation of the Brazilian Academy of Neurology aiming to guide professionals involved in the rehabilitation process to reduce functional disability and increase individual autonomy. Members of the group participated in web discussion forums with predefined themes, followed by videoconference meetings in which issues were discussed, leading to a consensus. These guidelines, divided into two parts, focus on the implications of recent clinical trials, systematic reviews, and meta-analyses in stroke rehabilitation literature. The main objective was to guide physicians, physiotherapists, speech therapists, occupational therapists, nurses, nutritionists, and other professionals involved in post-stroke care. Recommendations and levels of evidence were adapted according to the currently available literature. Part I discusses topics on rehabilitation in the acute phase, as well as prevention and management of frequent conditions and comorbidities after stroke.

Gait speed and spasticity are independently associated with estimated failure load in the distal tibia after stroke: an HR-pQCT study

This HR-pQCT study was conducted to examine bone properties of the distal tibia post-stroke and to identify clinical outcomes that were associated with these properties at this site. It was found that spasticity and gait speed were independently associated with estimated failure load in individuals with chronic stroke.

PURPOSE

(1) To examine the influence of stroke on distal tibia bone properties and (2) the association between these properties and clinical outcomes in people with chronic stroke.

METHODS

Sixty-four people with stroke (age, 60.8 ± 7.7 years; time since stroke, 5.7 ± 3.9 years) and 64 controls (age: 59.4 ± 7.8 years) participated in this study. High-resolution peripheral quantitative computed tomography (HR-pQCT) was used to scan the bilateral distal tibia, and estimated failure load was calculated by automated finite element analysis. Echo intensity of the medial gastrocnemius muscle and blood flow of the popliteal artery were assessed with ultrasound. The 10-m walk test (10MWT), Fugl-Meyer Motor Assessment (FMA), and Composite Spasticity Scale (CSS) were also administered.

RESULTS

The percent side-to-side difference (%SSD) in estimated failure load, cortical area, thickness, and volumetric bone mineral density (vBMD), and trabecular and total vBMD were significantly greater in the stroke group than their control counterparts (Cohen's d = 0.48-1.51). Isometric peak torque and echo intensity also showed significant within- and between-groups differences (p ≤ 0.01). Among HR-pQCT variables, the %SSD in estimated failure load was empirically chosen as one example of the strong discriminators between the stroke group and control group, after accounting for other relevant factors. The 10MWT and CSS subscale for ankle clonus remained significantly associated with the %SSD in estimated failure load after adjusting for other relevant factors (p ≤ 0.05).

CONCLUSION

The paretic distal tibia showed more compromised vBMD, cortical area, cortical thickness, and estimated failure load than the non-paretic tibia. Gait speed and spasticity were independently associated with estimated failure load. As treatment programs focusing on these potentially modifiable stroke-related impairments are feasible to administer, future studies are needed to determine the efficacy of such intervention strategies for improving bone strength in individuals with chronic stroke.

Relationship between bone strength index of the hemiparetic tibial diaphysis and muscle strength in people with chronic stroke: influence of muscle contraction type and speed

This study was conducted to examine the association between the tibial bone strength index and leg muscle strength of different contraction types and speeds among people with chronic stroke. We found that concentric muscle power at moderate speed was more associated with tibial bone strength index than other types.

INTRODUCTION

To compare the influence of muscle strength of different contraction types and speeds on the bone strength index of tibial diaphysis in people with chronic stroke.

METHODS

Eighty individuals with chronic stroke (age: 62.6 ± 8.0 years; men/women: 46/34; post-stroke duration: 9.0 ± 5.4 years) underwent scanning of the tibia at the 66% site on both sides using peripheral quantitative computed tomography. Each participant was also evaluated for isometric and dynamic (at 60°/s and 120°/s) strength of knee flexors/extensors and ankle dorsiflexors/plantarflexors using an isokinetic dynamometer. For a given contraction type and speed, the strength values of the four muscle groups were summed to yield a composite score. Multiple regression analysis was used to identify the association of the percent side-to-side difference (%SSD) in tibial polar-stress-strain index (p-SSI) with %SSD in muscle strength of different contraction types and speeds.

RESULTS

The p-SSI and all muscle strength parameters on the paretic side had lower values than the non-paretic side (p ≤ 0.001). The %SSD in concentric muscle power at angular speed of 60°/s (R² = 0.317, p = 0.006) and 120°/s (R² = 0.298, p = 0.020) remained independently associated with that in p-SSI, after controlling for age, sex, body mass index, post-stroke duration, motor impairment, spasticity, and physical activity level. The effect of isometric strength and eccentric muscle power was not significant in multivariate analysis.

CONCLUSIONS

Concentric muscle power was more predictive of %SSD in p-SSI at the tibial diaphysis than other contraction types and may be an important target for intervention to promote bone health in people with chronic stroke.

Determinants of estimated failure load in the distal radius after stroke: An HR-pQCT study

Bone health is often compromised after stroke and the distal radius is a common site of fragility fractures. The macro- and mircoproperties of bone tissue after stroke and their clinical correlates are understudied. The objectives of the study were to use High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT) to investigate the bone properties at the distal radius, and to identify the correlates of estimated failure load for the distal radius in people with chronic stroke. This was a cross-sectional study of 64 people with stroke (age: 60.8 ± 7.7 years, stroke duration: 5.7 ± 3.9 years) and 64 age- and sex-matched controls. Bilateral bone structural, densitometric, geometric and strength parameters of the distal radius were measured using HR-pQCT. The architecture, stiffness and echo intensity of the bilateral biceps brachii muscle and brachial artery blood flow were evaluated using diagnostic ultrasound. Other outcomes included the Fugl-Meyer Motor Assessment (FMA), Motor Activity Log (MAL), and Composite Spasticity Scale (CSS). The results revealed a significant side (paretic vs non-paretic for the stroke group, non-dominant vs dominant for controls) by group (stroke vs control) interaction effect for estimated failure load, cortical area, cortical thickness, trabecular number and trabecular separation, and all volumetric density parameters. Post-hoc analysis showed percent side-to-side differences in bone outcomes were greater in the stroke group than the control group, with the exception of trabecular thickness and intracortical porosity. Among the HR-pQCT variables, percent side-to-side difference in trabecular volumetric bone mineral density contributed the most to the percent side-to-side difference in estimated failure load in the stroke group (R² change = 0.334, β = 1.106). Stroke-related impairments (FMA, MAL, CSS) were found to be significant determinants of the percent side-to-side difference in estimated failure load (R² change = 0.233, β = -0.480). This was the first study to examine bone microstructure post-stroke. We found that the paretic distal radius had compromised bone structural properties and lower estimated failure load compared to the non-paretic side. Motor impairment was a determinant of estimated bone strength at the distal radius and may be a potential intervention target for improving bone health post-stroke.

Effects of different vibration frequencies on muscle strength, bone turnover and walking endurance in chronic stroke

This randomized controlled trial aimed to evaluate the effects of different whole body vibration (WBV) frequencies on concentric and eccentric leg muscle strength, bone turnover and walking endurance after stroke. The study involved eighty-four individuals with chronic stroke (mean age = 59.7 years, SD = 6.5) with mild to moderate motor impairment (Fugl-Meyer Assessment lower limb motor score: mean = 24.0, SD = 3.5) randomly assigned to either a 20 Hz or 30 Hz WBV intervention program. Both programs involved 3 training sessions per week for 8 weeks. Isokinetic knee concentric and eccentric extension strength, serum level of cross-linked N-telopeptides of type I collagen (NTx), and walking endurance (6-min walk test; 6MWT) were assessed at baseline and post-intervention. An intention-to-treat analysis revealed a significant time effect for all muscle strength outcomes and NTx, but not for 6MWT. The time-by-group interaction was only significant for the paretic eccentric knee extensor work, with a medium effect size (0.44; 95% CI: 0.01, 0.87). Both WBV protocols were effective in improving leg muscle strength and reducing bone resorption. Comparatively greater improvement in paretic eccentric leg strength was observed for the 30 Hz protocol.

Does Hip Bone Density Differ between Paretic and Non-Paretic Sides in Hemiplegic Stroke Patients? and Its Relationship with Physical Impairment

Background

Bone loss after stroke escalates the risk of fractures, mainly in the hip, leading to further disability in individuals with stroke. We aimed to investigate the skeletal effect of bone mineral density (BMD) based on the duration of onset of stroke, compare the BMD of the paretic and non-paretic sides, and elucidate the relationship between BMD and disability variables.

Methods

The 31 male hemiplegic stroke patients between 20 and 70 years of age with cerebral infarction or hemorrhage were considered in this study. Subacute and chronic cases included 13 and 18 patients with lag time from the onset of 1 to 6 months and beyond 6 months, respectively. BMD in the lumbar, paretic, and non-paretic hip as well as the disability variables were analyzed retrospectively.

Results

The subacute group showed a significant reduction in the femoral neck BMD on the paretic side compared to that on the non-paretic side based on T-scores (P=0.013). Bone loss was significantly correlated with lower limb muscle strength and overall physical impairment (P<0.05). The chronic group demonstrated significant reduction in femur neck and total femur BMD on the paretic side compared to that on the non-paretic side based on T-scores (P=0.002 and P<0.001, respectively). T-scores of BMD in the chronic phase were not significantly associated with the clinical parameters.

Conclusions

Early screening of bilateral hip BMD in the early stages after stroke, monitoring, and timely implementation of prevention strategies are important to minimize subsequent bone loss and prevent possible complications in patients who experience stroke.

Effects of Neurological Disorders on Bone Health

Neurological diseases, particularly in the context of aging, have serious impacts on quality of life and can negatively affect bone health. The brain-bone axis is critically important for skeletal metabolism, sensory innervation, and endocrine cross-talk between these organs. This review discusses current evidence for the cellular and molecular mechanisms by which various neurological disease categories, including autoimmune, developmental, dementia-related, movement, neuromuscular, stroke, trauma, and psychological, impart changes in bone homeostasis and mass, as well as fracture risk. Likewise, how bone may affect neurological function is discussed. Gaining a better understanding of brain-bone interactions, particularly in patients with underlying neurological disorders, may lead to development of novel therapies and discovery of shared risk factors, as well as highlight the need for broad, whole-health clinical approaches toward treatment.

Association between self-reported walking speed and calcaneal stiffness index in postmenopausal Japanese women

BACKGROUND

Osteoporosis and related fractures, a worldwide public health issue of growing concern, is characterized by compromised bone strength and an increased risk of fracture. Here we show an association between self-reported walking speed and bone mass among community-dwelling postmenopausal Japanese women aged 50 years and older. DESIGN; CROSS-SECTIONAL STUDY: Setting and Participants; The survey population included 1008 postmenopausal women 50-92 years of age residing in rural communities.

METHODS

Self-reported walking speed was ascertained by asking the participants: "Is your walking speed faster than others of the same age and sex?" to which participants responded "yes (faster)" or "no (moderate/slower)." Calcaneal stiffness index was measured.

RESULTS

Women with a faster self-reported walking speed were younger and had a lower BMI, higher stiffness index, and higher grip strength than women with a slower walking speed. Multiple linear regression analysis adjusted for age, BMI, grip strength, comorbidity, current smoking, and alcohol drinking status showed a significant association between faster self-reported walking speed and higher calcaneal stiffness index (p <  0.001).

CONCLUSIONS

Our findings suggest that questionnaires of walking speed may be useful for predicting bone mass and that a fast self-reported walking may benefit bone health in postmenopausal women.

Drug treatment strategies for osteoporosis in stroke patients

INTRODUCTION

Osteoporosis and subsequent fractures are well-recognized complications of stroke. However, drug treatment strategies for osteoporosis after stroke have been rarely discussed in the current guidelines for the management of stroke or osteoporosis.

AREAS COVERED

The authors review the epidemiology, characteristics, pathophysiology, and risk prediction of post-stroke osteoporosis and fractures. Then they provide an overview of existing evidence regarding drug treatment strategies for osteoporosis in stroke patients. They also review the effects on bone mineral density (BMD) and fractures for those drugs commonly used in stroke patients.

EXPERT OPINION

Currently, there is scarce evidence. A small randomized control trial suggested that a single use of 4 mg of intravenous zoledronate within 5 weeks of stroke onset was beneficial for preserving BMD, while simultaneous use of calcium and vitamin D supplements may be effective in preventing hypocalcemia. Further studies are needed to address several important issues of post-stroke osteoporosis, including who (the eligibility for treatment), when (the best timing of treatment), what (which drug), and how long (the best duration of treatment). On the other hand, physicians should bear in mind that drugs commonly used for stroke, such as statins or warfarin, may have beneficial or adverse effects on BMD and fracture risks.

The impact of stroke on bone properties and muscle-bone relationship: a systematic review and meta-analysis

To systematically review available evidence related to the characteristics of bone changes post-stroke and the relationship between various aspects of muscle function (e.g., strength, spasticity) and bone properties after stroke onset. An extensive online database search was undertaken (last search in January 2019). Articles that examined the bone properties in stroke patients were included. The quality of the studies was evaluated with the National Institutes of Health (NIH) Study Quality Assessment Tools. Publication bias of meta-analyses was assessed using the Egger's regression asymmetry test. The selection and evaluation of the articles were conducted by two independent researchers. Fifty-nine studies were identified. In subacute and chronic stroke studies, the skeletal sites in the paretic limbs sustained a more pronounced decline in bone quality than did their counterparts in the non-paretic limbs. The rate of changes showed a decelerating trend as post-stroke duration increased, but the timing of achieving the steady rate differed across skeletal sites. The magnitude of bone changes in the paretic upper limb was more pronounced than the paretic lower limb. There was a strong relationship between muscle strength/mass and bone density/strength index. Muscle spasticity seemed to have a negative impact on bone integrity in the paretic upper limb, but its influence on bone properties in the paretic lower limb was uncertain. Substantial bone changes in the paretic limbs occurred particularly in the first few months after stroke onset. Early intervention, muscle strength training, and long-term management strategies may be important to enhance bone health post-stroke. This review has also revealed the knowledge gaps which should be addressed in future research.

Peripheral Quantitative Computed Tomography: Review of Evidence and Recommendations for Image Acquisition, Analysis, and Reporting, Among Individuals With Neurological Impairment

In 2015, the International Society for Clinical Densitometry (ISCD) position statement regarding peripheral quantitative computed tomography (pQCT) did not recommend routine use of pQCT, in clinical settings until consistency in image acquisition and analysis protocols are reached, normative studies conducted, and treatment thresholds identified. To date, the lack of consensus-derived recommendations regarding pQCT implementation remains a barrier to implementation of pQCT technology. Thus, based on description of available evidence and literature synthesis, this review recommends the most appropriate pQCT acquisition and analysis protocols for clinical care and research purposes, and recommends specific measures for diagnosis of osteoporosis, assigning fracture risk, and monitoring osteoporosis treatment effectiveness, among patients with neurological impairment. A systematic literature search of MEDLINE, EMBASE^©, CINAHL, and PubMed for available pQCT studies assessing bone health was carried out from inception to August 8th, 2017. The search was limited to individuals with neurological impairment (spinal cord injury, stroke, and multiple sclerosis) as these groups have rapid and severe regional declines in bone mass. Of 923 references, we identified 69 that met review inclusion criteria. The majority of studies (n = 60) used the Stratec XCT 2000/3000 pQCT scanners as reflected in our evaluation of acquisition and analysis protocols. Overall congruence with the ISCD Official Positions was poor. Only 11% (n = 6) studies met quality reporting criteria for image acquisition and 32% (n = 19) reported their data analysis in a format suitable for reproduction. Therefore, based on current literature synthesis, ISCD position statement standards and the authors' expertise, we propose acquisition and analysis protocols at the radius, tibia, and femur sites using Stratec XCT 2000/3000 pQCT scanners among patients with neurological impairment for clinical and research purposes in order to drive practice change, develop normative datasets and complete future meta-analysis to inform fracture risk and treatment efficacy evaluation.

Risk of osteoporosis and pathologic fractures in cancer patients who underwent hematopoietic stem cell transplantation: a nationwide retrospective cohort study

Background

Long-term data on post-hematopoietic stem cell transplantation (HSCT) osteoporosis and fracture are limited. This study evaluated the long-term risk of osteoporosis and fracture in cancer patients who underwent HSCT.

Results

The incidence density rate of osteoporosis was 12.5 per 1000 person-years in the HSCT group, which was significantly higher than that in the non-HSCT group (5.65 per 1000 person-years) after adjustment for associated factors and consideration of competing risk factors (adjusted subhazard ratio, 1.48; 95% confidence interval, 1.06–2.07). The incidence density rate of fracture was 4.89 per 1000 person-years in the HSCT group, and the risk of fracture was 1.40 times higher in the HSCT group than in the non-HSCT group (95% confidence interval, 0.83–2.40). The vertebra was the most common site of fracture after HSCT (68.4%). The risk of osteoporosis and fracture significantly increased in post-HSCT patients with both hematological malignancies and solid tumors. Both autologous and allogeneic HSCTs increased the risk of osteoporosis, whereas only autologous HSCT recipients had an increased risk of fracture.

Materials and Methods

This nationwide retrospective cohort study analyzed data from Taiwan's National Health Insurance Research Database. We identified an HSCT group comprising 1040 cancer patients who underwent HSCT during 2000–2008 and a non-HSCT group comprising 4160 propensity score-matched cancer patients who did not undergo HSCT. All patients were followed up until the occurrence of osteoporosis; fracture; December 31, 2011; or withdrawal from the insurance program.

Conclusions

HSCT recipients have an increased risk of osteoporosis.

Upright activity and higher motor function may preserve bone mineral density within 6 months of stroke: a longitudinal study

PURPOSE

Bone fragility contributes to increased fracture risk, but little is known about the emergence of post-stroke bone loss. We investigated skeletal changes and relationships with physical activity, stroke severity, motor control and lean mass within 6 months of stroke.

METHODS

This is a prospective observational study. Participants were non-diabetic but unable to walk within 2 weeks of first stroke. Distal tibial volumetric bone mineral density (vBMD, primary outcome), bone geometry and microstructure (high-resolution peripheral quantitative computed tomography) were assessed at baseline and 6 months, as were secondary outcomes total body bone mineral content and lean mass (dual energy X-ray absorptiometry), bone metabolism (serum osteocalcin, N-terminal propeptide of type 1 procollagen (P1NP), C-terminal telopeptide of type 1 collagen (CTX)), physical activity (PAL2 accelerometer) and motor control (Chedoke McMaster) which were also measured at 1 and 3 months.

RESULTS

Thirty-seven participants (69.7 years (SD 11.6), 37.8% females, NIHSS 12.6 (SD 4.7)) were included. The magnitude of difference in vBMD between paretic and non-paretic legs increased within 6 months, with a greater reduction observed in paretic legs (mean difference = 1.5% (95% CI 0.5, 2.6), p = 0.007). At 6 months, better motor control was associated with less bone loss since stroke (r = 0.46, p = 0.02). A trend towards less bone loss was observed in people who regained independent walking compared to those who did not (p = 0.053). Higher baseline daily count of standing up was associated with less change in bone turnover over 6 months: osteocalcin (r = -0.51, p = 0.01), P1NP (r = -0.47, p = 0.01), CTX (r = -0.53, p = 0.01).

CONCLUSION

Better motor control and walking recovery were associated with reduced bone loss. Interventions targeting these impairments from early post-stroke are warranted.

CLINICAL TRIAL REGISTRATION

URL: http://www.anzctr.org.au . Unique identifier: ACTRN12612000123842.

Acute bone changes after lower limb amputation resulting from traumatic injury

Bone health is critical for lower limb amputees, affecting their ability to use a prosthesis and their risk of osteoporosis. We found large losses in hip bone mineral density (BMD) and in amputated bone strength in the first year of prosthesis use, suggesting a need for load bearing interventions early post-amputation.

INTRODUCTION

Large deficits in hip areal BMD (aBMD) and residual limb volumetric BMD (vBMD) occur after lower limb amputation; however, the time course of these bone quality changes is unknown. The purpose of this study was to quantify changes in the amputated bone that occur during the early stages post-amputation.

METHODS

Eight traumatic unilateral amputees (23-53 years) were enrolled prior to surgery. Changes in total body, hip, and spine aBMD (dual-energy X-ray absorptiometry); in vBMD, stress-strain index (SSI), and muscle cross-sectional area (MCSA) (peripheral QCT); and in bone turnover markers were assessed after amputation prior to prosthesis fitting (pre-ambulatory) and at 6 and 12 months walking with prosthesis.

RESULTS

Hip aBMD of the amputated limb decreased 11-15%, which persisted through 12 months. The amputated bone had decreases (p < 0.01) in BMC (-26%), vBMD (-21%), and SSI (-25%) from pre-ambulatory to 6 months on a prosthesis, which was maintained between 6 and 12 months. There was a decrease (p < 0.05) in the proportion of bone >650 mg/cm³ (58 to 43% of total area) or >480 mg/cm³ (65% to 53%), suggesting an increase in cortical porosity after amputation. Bone alkaline phosphatase and sclerostin were elevated (p < 0.05) at pre-ambulatory and then decreased towards baseline. Bone resorption markers were highest at surgery and pre-ambulatory and then progressively decreased (p < 0.05).

CONCLUSIONS

Rapid and substantial losses in bone content and strength occur early after amputation and are not regained by 12 months of becoming ambulatory. Early post-amputation may be the most critical window for preventing bone loss.