Incidental bilateral calcaneal fractures following overground walking with a wearable robotic exoskeleton in a wheelchair user with a chronic spinal cord injury: is zero risk possible?

  • A. Bass
  • S.N. Morin
  • M. Vermette
  • M. Aubertin-Leheudre
  • D.H. GagnonEmail author
Case Report


Many individuals with spinal cord injury (SCI) rely on wheelchairs as their primary mode of locomotion leading to reduced weight-bearing on the lower extremities, which contributes to severe bone loss and increased risk of fragility fractures. Engaging in a walking program may reverse this vicious cycle, as this promotes lower extremity weight-bearing and mobility, which may reduce bone loss and fragility fracture risk. However, fragility fracture risk associated with the use of wearable robotic exoskeletons (WREs) in individuals with SCI needs consideration. A 35-year-old man with chronic complete sensorimotor SCI (neurological level = T6) and low initial bone mineral density enrolled in a 6- to 8-week WRE-assisted walking program after successfully completing an initial clinical screening process and two familiarization sessions with the WRE. However, after the first training session with the WRE, he developed bilateral localized ankle edema. Training was suspended, and a CT-scan revealed bilateral calcaneal fractures, which healed with conservative treatment over a 12-week period. Opportunities for improving clinical screening and WRE design are explored. The relevance of developing clinical practice guidelines for safe initiation and progression of intensity during WRE-assisted walking programs is highlighted. This case of bilateral calcaneal fractures illustrates that aiming for “zero risk” during WRE-assisted walking programs may not be realistic. Although WREs are a relatively new technology, current evidence confirms their potential to greatly improve health and quality of life in individuals with chronic SCI. Hence, ensuring their safe use remains a key priority.


Assistive technology Locomotion Osteoporosis Rehabilitation Robotics Spinal cord injury 


Compliance with ethical standards

Conflicts of interest



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Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2020

Authors and Affiliations

  1. 1.School of Rehabilitation, Faculty of MedicineUniversité de MontréalMontrealCanada
  2. 2.Pathokinesiology LaboratoryCentre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR) of the Centre Intégré Universitaire de Santé et Services Sociaux (CIUSSS) du Centre-Sud-de-l’Île-de-MontréalMontrealCanada
  3. 3.Department of MedicineMcGill UniversityMontrealCanada
  4. 4.Department of Exercise ScienceUniversité du Québec à MontréalMontrealCanada

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