Northwestern University Feinberg School of Medicine

Northwestern University Prosthetics-Orthotics Center

Sensory-Motor Mechanisms Underlying Fall Risk in Transtibial Amputees

Principal Investigator: Matthew J. Major, PhD 

Mentors: Steven A. Gard, PhD (Jesse Brown VAMC); Mark Grabiner, PhD (University of Illinois Chicago); Young-Hui Chang (Georgia Institute of Technology); Marc Applebaum, MD (Jesse Brown VAMC); Keith Gordon, PhD (Edward Hines, Jr. VAMC); Mark Huang, MD (Rehabilitation Institute of Chicago)

Funded by: Department of Veterans Affairs, Rehabilitation Research and Development, Career Development Award (CDA-2)

Status: In progress

Purpose

Understanding the role of sensory feedback to minimize fall risk.

Lower limb prosthesis users are known to be at a substantially increased fall risk compared to able-bodied individuals. The interaction among increased fall risk, reduced balance confidence, and high prevalence of a fear of falling often leads to restricted mobility and loss of independence in this patient group. Furthermore, fall risk increases with progressing age, as aging affects musculoskeletal and somatosensory systems that are vital to controlling upright balance and are already compromised in persons with lower limb amputation.

The cause of falls and the role that sensory-motor function for maintaining upright balance plays in fall risk of lower limb prosthesis users is poorly understood. The effects of reduced sensory-motor function on upright balance in older adults has been extensively studied and led to the development of effective assessment tools and intervention strategies that can minimize fall risk. However, the dearth of similar studies and a relatively poor understanding of the complicating effects of lower limb amputation on upright balance have significantly hampered progress toward addressing this important concern for lower limb prosthesis users. Therefore, the primary objective of this research is to develop an improved understanding of the sensory-motor mechanisms underlying upright balance and fall risk in older persons with lower limb amputation.

A better understanding of the relationships between fall risk and various outcome measures can inform the development of intervention techniques to improve functional balance. An improvement in upright balance will reduce the incidence of falls and fall-related injuries in this patient group; and also will increase their daily community participation, encourage independent living, and improve their overall quality of life.

References

Major M, Fatone S, Roth EJ. (2013) Validity and reliability of the Berg Balance Scale for community-dwelling persons with lower-limb amputation. Archives of Physical Medicine and Rehabilitation 94:2194-202.

Major M, Stine R, Gard SA. (2013) The effects of walking speed and prosthetic ankle adapters on upper extremity dynamics and stability-related parameters in bilateral transtibial amputee gait. Gait & Posture 38:858-863.