Trabecular bone score in adults with cerebral palsy.

Abstract

Bone fragility in cerebral palsy (CP) is secondary to a complex interplay of functional, hormonal, and nutritional factors that affect bone remodelling. A greater understanding of bone microarchitectural changes seen in CP should assist therapeutic decision making. To examine the relationship between trabecular bone score (TBS), BMD and fractures in adults with CP; the influence of clinical factors and body composition on bone microarchitecture were explored. Retrospective cross-sectional study. 43 adults (25 male) with CP of median age 25 years (interquartile range 21.4-33.9) who had evaluable dual-energy X-ray absorptiometry imaging of the lumbar spine from a single tertiary hospital between 2005-March 2018. 24/43 (55.8%) of patients had TBS values indicating intermediate or high risk of fracture (<1.31). TBS correlated with areal BMD at the lumbar spine, femoral neck and total body. TBS was significantly associated with arm and leg lean mass, with adjustment for age, gender and height (adjusted R2 = 0.18, p = 0.042 for arm lean mass; adjusted R2 = 0.19, p = 0.036 for leg lean mass). There was no difference in TBS when patients were grouped by fracture status, anticonvulsant use, gonadal status or use of PEG feeding. TBS was lower in non-ambulatory patients compared with ambulatory patients (1.28 vs 1.37, p = 0.019). Abnormal bone microarchitecture, as measured by TBS, was seen in >50% of young adults with CP. TBS correlated with both areal BMD and appendicular lean mass. Maintaining muscle function is likely to be important for bone health in young adults with CP and needs to be confirmed in further studies.