Effects of Passive Versus Dynamic Loading Interventions on Bone Health in Children Who Are Nonambulatory

Damcott, Megan PhD; Blochlinger, Sheila PT, ATP; Foulds, Richard PhD

doi: 10.1097/PEP.0b013e318299127d
Research Article

Purpose: To investigate the effectiveness of a novel dynamic standing intervention compared with a conventional passive standing intervention on bone health in children with cerebral palsy who are nonambulatory.

Methods: Four children in passive standers and 5 in dynamic standers were followed for 15 months (standing 30 min/d, 5 d/wk). Dual-energy x-ray absorptiometry scans of the distal femur were obtained at 3-month intervals to measure changes in bone mineral density (BMD), bone mineral content, and area.

Results: Increases in BMD were observed during dynamic standing (P < .001), whereas passive standing appeared to maintain the baseline BMD. Increases in bone mineral content were observed in each standing intervention (P < .001), with dynamic standing inducing greater increases. Increases in area were comparable between interventions (P = .315).

Conclusions: Dynamic standing demonstrated the potential of moderate-magnitude, low-frequency loading to increase cortical BMD. Further investigations could provide insight into the mechanisms of bone health induced through loading interventions.

Children's bone health is reported to improve in those who received a dynamic standing intervention and to remain stable among those who received a passive standing intervention.

Human Performance and Engineering Laboratory (Dr Damcott), Kessler Foundation Research Center, West Orange, New Jersey; Rehabilitation Technology Department (Ms Blochlinger), Children's Specialized Hospital, Mountainside, New Jersey; Department of Biomedical Engineering (Dr Foulds), New Jersey Institute of Technology, Newark, New Jersey.

Correspondence: Megan Damcott, PhD, Human Performance and Engineering Laboratory, Kessler Foundation Research Center, 1199 Pleasant Valley Way, West Orange, NJ 07052 (mdd7@njit.edu).

Grant support: National Institute on Disability and Rehabilitation Research, Rehabilitation Engineering Research Center, grant H133E0511-06.

The authors declare no conflicts of interest.

At the time this study was completed, Dr Megan Damcott was a student at New Jersey Institute of Technology/University of Medicine and Dentistry of New Jersey, Biomedical Engineering Department, Newark, New Jersey, completing her doctorate of philosophy.

© 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins and the Section on Pediatrics of the American Physical Therapy Association.