Bone Density and Metabolism in Children and Adolescents With Moderate to Severe Cerebral Palsy

Abstract

ABSTRACT. Objectives. Diminished bone density and a propensity to fracture with minimal trauma are common in children and adolescents with moderate to severe cerebral palsy (CP). The purpose of this study was to provide a detailed evaluation of bone mineral density (BMD) and metabolism in this population and to assess the relationship of these measures to multiple other clinical, growth, and nutrition variables.Methods. The study group consisted of 117 subjects ages 2 to 19 years (mean: 9.7 years) with moderate to severe CP as defined by the Gross Motor Functional Classification scale. Population-based sampling was used to recruit 62 of the participants, which allows for estimations of prevalence. The remaining 55 subjects were a convenience sampling from both hospital-and school-based sources. The evaluation included measures of BMD, a detailed anthropometric assessment of growth and nutritional status, medical and surgical history, the Child Health Status Questionnaire, and multiple serum analyses. BMD was measured in the distal femur, a site specifically developed for use in this contracted population, and the lumbar spine. BMD measures were converted to age and gender normalized z scores based on our own previously published control series (n > 250).Results. Osteopenia (BMD z score <؊2.0) was found in the femur of 77% of the population-based cohort and in 97% of all study participants who were unable to stand and were older than 9 years. BMD was not as low in the lumbar spine (population-based cohort mean ؎ standard error z score: ؊1.8 ؎ 0.1) as in the distal femur (mean z score: ؊3.1 ؎ 0.2). Fractures had occurred in 26% of the children who were older than 10 years. Multiple clinical and nutritional variables correlated with BMD z scores, but interpretation of these findings is complicated by covariance among variables. In stepwise regression analyses, it was found that severity of neurologic impairment as graded by Gross Motor Functional Classification level, increasing difficulty feeding the child, use of anticonvulsants, and lower triceps skinfold z scores (in decreasing order of importance) all independently contribute to lower BMD z scores in the femur.Conclusions. Low BMD is prevalent in children with moderate to severe CP and is associated with significant fracture risk. The underlying pathophysiology is complex, with multiple factors contributing to the problem and significant variation between different regions of the skeleton. Pediatrics 2002;110(1). URL: http://www. pediatrics.org/cgi/content/full/110/1/e5; cerebral palsy, bone mineral density, osteoporosis, pediatrics, bone metabolism, growth, nutrition, osteopenia.

Bone fracture in physically disabled children attending schools for handicapped children in Japan

“…In a population-based setting, Leet et al [9] investigated fracture histories obtained from medical charts of 763 CP patients (aged between 1.3 and 18 years), and found that 70% of fractures involved the lower extremities. These results are consistent with the finding that bone mineral density (BMD) in the femur is severely diminished in children with moderate to severe CP [3]. Shiragaki et al [17] also showed that BMD in the lower limbs was lower than other bone sites in …”

“…Increased risk of fracture in physically disabled children may be associated with their low bone mass. We did not assess bone mass of the subjects, but other researchers have shown that lower bone mass has been reported in children with CP [3,4]. Likewise, low vitamin D status, which could adversely affect normal bone metabolism, has been reported in children with neuromuscular disorders [5,14], and thus may also be associated with increased risk of fracture.…”

“…Children with physical disabilities such as cerebral palsy (CP) have been known to have osteopenia [2] and low bone mineral density [3,4]. This may be due in part to low or no mobility and to hypovitaminosis D caused by immobility [5].…”

Children with Spina Bifida are at Risk for Low Bone Density

“…The lateral distal femoral DXA scan reflects BMD in the legs, the regions most likely to incur fractures. Fractures in this population differed from fractures seen in other neuromuscular disorders such as cerebral palsy [4]; the nature of the radiographic changes suggested subperiosteal hemorrhage and Charcot-like changes in the physis, which might be attributed to chronic repetitive trauma and could not properly be described as an ''insufficiency fracture.'' According to the ISCD, only children who have experienced an insufficiency fracture (a fracture occurring with minimal trauma) should be diagnosed with ''osteoporosis.''…”

Low bone turnover phenotype in Rett syndrome: results of biochemical bone marker analysis

“…In cerebral palsy (CP) patients with motor deficiencies the examination of biochemical bone markers (OC, B-ALP, and N-telopeptides) have shown a wide variety in serum levels (30,31) and no significant association with measures of bone mass as BMD z scores of the lumbar spine (30,31) and distal femur region (31). Furthermore, a study comparing children with CP and healthy children reported no significant differences in both bone formation (B-ALP) and (urinary) resorption markers (32).…”