Longitudinal assessment of bone growth and development in a facility-based population of young adults with cerebral palsy

Secondary Osteoporosis

Osteoporosis is a global public health problem, with fractures contributing to significant morbidity and mortality. Although postmenopausal osteoporosis is most common, up to 30% of postmenopausal women, > 50% of premenopausal women, and between 50% and 80% of men have secondary osteoporosis. Exclusion of secondary causes is important, as treatment of such patients often commences by treating the underlying condition. These are varied but often neglected, ranging from endocrine to chronic inflammatory and genetic conditions. General screening is recommended for all patients with osteoporosis, with advanced investigations reserved for premenopausal women and men aged < 50 years, for older patients in whom classical risk factors for osteoporosis are absent, and for all patients with the lowest bone mass (Z-score ≤ -2). The response of secondary osteoporosis to conventional anti-osteoporosis therapy may be inadequate if the underlying condition is unrecognized and untreated. Bone densitometry, using dual-energy x-ray absorptiometry, may underestimate fracture risk in some chronic diseases, including glucocorticoid-induced osteoporosis, type 2 diabetes, and obesity, and may overestimate fracture risk in others (eg, Turner syndrome). FRAX and trabecular bone score may provide additional information regarding fracture risk in secondary osteoporosis, but their use is limited to adults aged ≥ 40 years and ≥ 50 years, respectively. In addition, FRAX requires adjustment in some chronic conditions, such as glucocorticoid use, type 2 diabetes, and HIV. In most conditions, evidence for antiresorptive or anabolic therapy is limited to increases in bone mass. Current osteoporosis management guidelines also neglect secondary osteoporosis and these existing evidence gaps are discussed.

Adaptive Cycling: Injuries and Health Concerns

Para-cycling has high rates of acute injuries. The underlying medical conditions of para-athletes predispose these cyclists to injury patterns and sequelae different from those of their able-bodied counterparts. Such injuries include an increased incidence of upper-extremity and soft tissue injuries, along with predisposition for respiratory, skin, genitourinary, and heat-related illnesses. There are no validated sideline assessment tools or return-to-play protocols for sports-related concussion in wheelchair user para-athletes or those with balance deficits. Para-cyclists may be at increased risk for relative energy deficiency in sport due to competitive pressure to maintain certain weights and increased incidence of low bone mineral density.

Critical periods of bone health across the lifespan for individuals with cerebral palsy: Informing clinical guidelines for fracture prevention and monitoring

BACKGROUND

Skeletal fragility is a major burden for individuals with cerebral palsy (CP), but little is known clinically about when to prevent fractures or monitor bone health for this population. Critical periods of bone health (CPBH) are important windows for intervention to augment bone growth or mitigate bone loss. However, CPBH from the general population may not align with the needs or timing of skeletal fragility for individuals with CP. The objective of this study was to identify discrepancies when evaluating individuals with CP using CPBH across the lifespan from the general population, and propose new CP-specific CPBH.

METHODS

Data from 2016 administrative claims databases were used, including the Optum's De-identified Clinformatics® Data Mart Database and a random 20% sample of the Medicare fee-for-service database from the Centers for Medicare and Medicaid Services. Sex-stratified fracture prevalence was compared between individuals with and without CP across the lifespan starting at 2 years of age using age groups to capture important stages of development and 3-4-year age bands in adulthood (up to >80 years). Sex-specific CPBH from the general population included: rapid bone accrual, peak bone mass, menopause, and elderly.

RESULTS

There were 23,861 individuals with CP and 9,976,161 individuals without CP. CPBH from the general population did not align with the timing of skeletal fragility for CP. For example, fractures were rare and decreased throughout the CPBH of peak bone mass for males without CP, but males with CP had a greater relative fracture risk (2.9-5.6-fold higher) and a substantially increased rate of fracture (CP-slope 14× higher than non-CP-slope). For females with CP, fracture risk was increased by 18-21 years, with additional inflection points (e.g., decade before menopause and again by 57-60 years). For males with CP, fracture risk in mid-life exhibited a pattern similar to elderly males without CP.

CONCLUSIONS

This study identified discrepancies in evaluating fracture risk for individuals with CP if using established CPBH from the general population. We therefore propose new CP- and sex-specific CPBH for fracture monitoring and prevention.

The Utility of DXA Assessment at the Forearm, Proximal Femur, and Lateral Distal Femur, and Vertebral Fracture Assessment in the Pediatric Population: 2019 ISCD Official Position

Dual-energy X-ray absorptiometry (DXA) is widely used in the evaluation of bone fragility in children. Previous recommendations emphasized total body less head and lumbar spine DXA scans for clinical bone health assessment. However, these scan sites may not be possible or optimal for all groups of children with conditions that threaten bone health. The utility of DXA scans of the proximal femur, forearm, and radius were evaluated for adequacy of reference data, precision, ability of predict fracture, and applicability to all, or select groups of children. In addition, the strengths and limitations of vertebral fracture assessment by DXA were evaluated. The new Pediatric Positions provide guidelines on the use of these additional measures in the assessment of skeletal health in children.

Longitudinal changes in bone density in adolescents and young adults with cerebral palsy: A case for early intervention

CONTEXT

Cerebral palsy (CP) is a motor disorder affecting movement, muscle tone and posture due to damage to the foetal or infant brain. The subsequent lack of ambulation, nutritional deficiencies, anticonvulsant use and hormonal deficiencies have been implicated in the low bone mass associated with this condition.

OBJECTIVE

To assess changes in areal bone mineral density (aBMD) during adolescence and young adulthood in individuals with CP. The effect of ambulation, nutrition, hypogonadism on longitudinal changes in aBMD is also examined.

DESIGN

Retrospective longitudinal study.

SETTING AND PARTICIPANTS

Forty-five subjects with CP who had longitudinal dual-energy X-ray absorptiometry (DXA) scans at a single tertiary hospital between 2006 and 2018.

RESULTS

Mean age at first DXA was 19.4 years (range: 10-36 years), 57.8% were male and 80% were nonambulatory. The mean Z-scores at baseline were <-2.0 at all sites - lumbar spine (LS), femoral neck (FN), total hip (TH) and total body (TB). The median change in aBMD was +1.2%-1.9% per year in all subjects but in those <20 years of age, the median change was 4%-8% per year. Z-scores across all sites remained stable over time. Reduced functional state as measured by the gross motor functional classification scale (GMFCS) had a small negative effect on aBMD over time.

CONCLUSION

In adolescents with CP, low bone mass was evident from the baseline DXA. However, significant bone accrual occurred during the second decade, followed by bone maintenance in young adulthood. Future studies should focus on optimizing bone health from early childhood.

Incidence of osteoarthritis, osteoporosis and inflammatory musculoskeletal diseases in adults with cerebral palsy: A population-based cohort study

BACKGROUND

People with cerebral palsy (CP) may be at increased risk of musculoskeletal conditions due to various factors including malnutrition and abnormal levels of skeletal loading. This study aimed to compare the incidence of osteoporosis, osteoarthritis and inflammatory musculoskeletal diseases between adults with and without CP.

METHODS

A population based cohort study was conducted using data from the Clinical Practice Research Datalink collected between 1987 and 2015. Adults with CP were matched to adults without CP for age, sex and general practice. Cox models, stratified by matched set and adjusted for potential confounders, were fitted to compare the risk of osteoporosis, osteoarthritis and inflammatory musculoskeletal diseases.

RESULTS

1705 adults with CP were matched to 5115 adults without CP. Adults with CP had an increased risk of osteoporosis in unadjusted (Hazard Ratio (HR) 3.67, 95% Confidence Interval (CI) 2.32 to 5.80, p < 0.001) and adjusted (HR 6.19, 95% CI 3.37 to 11.39, p < 0.001) analyses. No evidence of increased risk of inflammatory musculoskeletal diseases was observed in unadjusted or adjusted analyses. For osteoarthritis no evidence of increased risk was seen in the unadjusted analysis, but evidence of an increased risk was seen when the analysis was adjusted for alcohol consumption, smoking status, and mean yearly general practice (GP) visits (HR 1.54, 95% CI 1.17 to 2.02, p < 0.001).

CONCLUSIONS

After accounting for potential confounding variables, we found that CP is associated with increased risk of osteoporosis and osteoarthritis. These findings provide the strongest epidemiological evidence to date for increased risk of osteoporosis and osteoarthritis in people with CP, and highlight need for clinical awareness of such conditions in this population.

Low Energy Availability, Menstrual Dysfunction, and Low Bone Mineral Density in Individuals with a Disability: Implications for the Para Athlete Population

Low energy availability, functional hypothalamic amenorrhea, and low bone mineral density are three interrelated conditions described in athletic women. Although described as the female athlete triad (Triad), males experience similar health concerns. The literature suggests that individuals with a disability may experience altered physiology related to these three conditions when compared with the able-bodied population. The goal of this review is to describe the unique implications of low energy availability, low bone mineral density, and, in females, menstrual dysfunction in individuals with a disability and their potential impact on the para athlete population. A literature review was performed linking search terms related to the three conditions with six disability categories that are most represented in para sport. Few articles were found that directly pertained to athletes, therefore, the review additionally characterizes literature found in a non-athlete population. Review of the available literature in athletes suggests that both male and female athletes with spinal cord injury demonstrate risk factors for low energy availability. Bone mineral density may also show improvements for wheelchair athletes or athletes with hemiplegic cerebral palsy when compared with a disabled non-athlete population. However, the prevalence of the three conditions and implications on the health of para athletes is largely unknown and represents a key gap in the sports medicine literature. As participation in para sport continues to increase, further research is needed to understand the impact of these three interrelated health concerns for athletes with a disability, accompanied by educational initiatives targeting athletes, coaches, and health professionals.

Incidence and risk factors of hardware-related complications after proximal femoral osteotomy in children and adolescents

Proximal femoral osteotomy has been used in cerebral palsy, Perthes disease, hip dysplasia, idiopathic femoral anteversion, and various hip diseases in children and adolescents. Conventionally, a blade plate (BP) has been used. However, the pediatric locking compression plate (LCP) has recently been applied widely. We compared the hardware-related complications of the BP and the LCP as well as the factors influencing these complications in patients who have undergone a proximal femoral osteotomy in children and adolescents. We enrolled consecutive patients aged less than or equal to 20 years who had undergone proximal femoral osteotomy with BP or LCP between May 2003 and December 2014, and who were followed up until 6 months after hardware removal. Following consensus building, hardware-related complications were identified from the patients' medical records and hip radiographs. Patient age, sex, type of plate, and Gross Motor Function Classification System (GMFCS) level in cerebral palsy patients were evaluated as possible risk factors, and a generalized estimating equation was used to assess the risk factors for hardware-related complications. A total of 417 hips from 251 patients were finally included in this study. Seven losses of fixation around the plate (five patients, 3.0%) occurred in the BP, three implant-related fractures (three patients, 3.6%) occurred in the LCP, and there was no significant difference (P=0.74). All hardware-related complications occurred in cerebral palsy patients, and the implant-related fractures occurred in patients with GMFCS IV/V. The risk of complications increased with age (P=0.002). The risk of loss of fixation around the BP is a well-known complication. However, LCP is not without hardware-related complications. The LCP provides strong stability of fixation. However, it is speculated that the LCP is related to implant-related fractures because of the stress shielding effect. Therefore, care should be exercised when using a locking plate in patients with osteoporosis, such as cerebral palsy with GMFCS IV/V.

LEVEL OF EVIDENCE

Therapeutic Level III.

Bone mineral density and nutritional status in children with quadriplegic cerebral palsy

This study demonstrated the relationship of low bone mineral density (BMD) with the degree of motor impairment, method of feeding, anthropometric indicators, and malnutrition in children with quadriplegic cerebral palsy (CP). The control of these factors could optimize adequate bone mineralization, avoid the risk of osteoporosis, and would improve the quality of life.

PURPOSE

The purpose of the study is to explore the relationship between low BMD and nutritional status in children with quadriplegic CP.

METHODOLOGY

A cross-sectional analytical study included 59 participants aged 6 to 18 years with quadriplegic CP. Weight and height were obtained with alternative measurements, and weight/age, height/age, and BMI/age indexes were estimated. The BMD measurement obtained from the lumbar spine was expressed in grams per square centimeter and Z score (Z). Unpaired Student's t tests, chi-square tests, odds ratios, Pearson's correlations, and linear regressions were performed.

RESULTS

The mean of BMD Z score was lower in adolescents than in school-aged children (p = 0.002). Patients with low BMD were at the most affected levels of the Gross Motor Function Classification System (GMFCS). Participants at level V of the GMFCS were more likely to have low BMD than levels III and IV [odds ratio (OR) = 5.8 (confidence interval [CI] 95% 1.4, 24.8), p = 0.010]. There was a higher probability of low BMD in tube-feeding patients [OR = 8.6 (CI 95% 1.0, 73.4), p = 0.023]. The probability of low BMD was higher in malnourished children with weight/age and BMI indices [OR = 11.4 (1.3, 94), p = 0.009] and [OR = 9.4 (CI 95% 1.1, 79.7), p = 0.017], respectively.

CONCLUSION

There was a significant relationship between low BMD, degree of motor impairment, method of feeding, and malnutrition. Optimizing these factors could reduce the risk of osteopenia and osteoporosis and attain a significant improvement of quality of life in children with quadriplegic CP.

Skeletal Maturation and Mineralisation of Children with Moderate to Severe Spastic Quadriplegia

INTRODUCTION

Diminished bone mineral density and delayed skeletal maturation are common in children with spastic quadriplegia.

AIM

The purpose of our study was to evaluate the Bone Mineral Density (BMD) of children with moderate to severe spastic quadriplegia and its relationship with other variables like nutrition and growth.

MATERIALS AND METHODS

This was a hospital based, cross- sectional, case-control study. Forty-two (28 males, 14 females) children with spastic quadriplegia and 42 (24 males, 18 females) healthy children were included in the study. BMD of cases and control were measured by Dual Energy X-ray Absorptiometry (DEXA). Radiographs of left hand and wrist of cases and controls were taken and bone age was determined.

RESULTS

BMD values of upper extremity, lower extremity, thoraco-lumbar spine and pelvis in cases were lower than those of controls (p <0.0001). In children with non severe malnutrition, 75% of the cases had lower bone age than chronological age, whereas all cases with severe malnutrition had lower bone age than chronological age. Step wise regression analysis showed that nutritional status independently contributed to lower BMD values but the BMD values did not correlate significantly with the use of anticonvulsant drugs and presence of physical therapy.

CONCLUSION

Decreased BMD and delayed bone age is prevalent in children with spastic quadriplegia and nutritional status is an important contributing factor.

Bone mineral density in mucopolysaccharidosis IVB

To date, the only published reports of bone mineral density (BMD) in MPS IV involve patients with MPS IVA; no reports exist describing BMD for MPS IVB. In this prospective study of BMD in three patients with MPS IVB, BMD was acquired by dual-energy X-ray absorptiometry (DXA) at whole body (WB), lumbar spine (LS), and lateral distal femur (LDF). Functional abilities, ambulatory status, medical history, and height z-score were evaluated. Three patients with MPS IVB (two females), aged 17.7, 31.4 and 31.7 years, were evaluated. Every patient was ambulatory and one sustained two fractures caused by trauma. Whole body and hip DXA scans were technically invalid in every patient due to the presence of prosthetic hip hardware. Lumbar spine was valid in only 1 patient due skeletal abnormalities, and was normal (Z-score of − 0.8). The LDF was valid in every patient and was low at all three regions of interest: average LDF z-scores were − 3.1 (range, − 2.9 to − 3.6), − 2.3 (range, − 2.0 to − 2.5), and − 2.1 (range, − 2.0 to − 2.3) for region 1–region 3, respectively. Patients with MPS IVB have low BMD of the lower extremities even with full-time ambulation. Routine body sites to measure by DXA were problematic; hip and WB were invalid due to artifact, and LS had limited utility. The LDF was the only body site consistently available on all patients. Patients did not experience low-energy fractures despite low BMD.

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This is the first report of BMD in MPS IVB.

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Assessment of BMD in 3 patients with Morquio B is challenging using typical body sites measured by DXA.

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Hip replacements preclude proximal femur and whole body DXA; abnormal vertebral shape limits the use of lumbar spine DXA.

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The lateral distal femur DXA was obtainable and technically valid.

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Despite ambulation, lower extremity BMD was below normal.