Northwestern University Feinberg School of Medicine

Northwestern University Prosthetics-Orthotics Center

Effect of Spine Surgery on Energy Expenditure of Walking

Principal Investigator: Steven Gard, PhD

Co-Investigators: Stefania Fatone, PhD, and Aruna Ganju, MD**

** Department of Neurological Surgery, Northwestern University

Funded by: Department of Veterans Affairs (VA)


The ability to walk efficiently is integral to the performance of many activities of daily living and the ability to function independently. Self-reported physical function of people with spinal problems is low and people with abnormal posture had poorer functional performance during standardized tests. It has been suggested that the spine plays an important role during ambulation as a shock absorber and energy saving system. Studies of energy expenditure in people with spine pathologies are limited: increased oxygen uptake has been reported in subjects with scoliosis, irrespective of the degree of spinal curvature; decreased endurance has been reported in women with lumbar spine deformity; and increased energy expenditure during standing has been reported in women with osteoporosis. It is not clear what the impact of surgery is on energy expenditure in people with spinal deformity.

Degenerative spine disease affects many Americans and the incidence/prevalence of this condition is increasing as the population ages, incurring a significant cost to both the individual and society. Spinal column degeneration results in structural deformity, neurologic compromise, and considerable pain; for many, these symptoms result in surgery. Surgery stabilizes and re-aligns the spine, thus reducing pain. Spinal deformity alters cranio-spino-pelvic orientation and leads to lower limb compensatory mechanisms to maintain an upright posture, which may be associated with increased energy expenditure. The purpose of this project is to evaluate the impact of surgery on quality of life as it relates to the effort and efficiency of walking in patients with degenerative spine disease.

A subject participating in an energy expenditure study.

A subject participating in an energy expenditure study.