The relation between walking capacity and clinical correlates in survivors of chronic spinal poliomyelitis.

Abstract

To examine (1) common clinical measures that may influence walking performance in the six-minute walk test (6MWT) in people with chronic poliomyelitis and (2) the test-retest reliability of the 6MWT distance, lower-extremity muscle strength, balance, and balance confidence on separate trials. A prospective quasi-experimental study. University-based postpolio clinic. Nineteen survivors of poliomyelitis (mean age, 62.2+/-1.9y; time since polio onset, 54.4+/-8.79y). Not applicable. 6MWT distance, rate-pressure product (RPP), Physiological Cost Index (PCI), ratings of perceived exertion (RPE), pain, fatigue, strength, standing balance, balance confidence, limb-length discrepancy, and lung function. The 6MWT distance correlated with PCI, pretest pain, lower-extremity muscle strength, balance, balance confidence, corrected leg-length discrepancy, and lung function but not with RPP, RPE, posttest pain, or pretest and posttest fatigue. The PCI correlated with balance confidence and lung function. About 68% of the variance in 6MWT distance was accounted for by balance and pretest pain. The P value was set at .05. With stringent standardization of the 6MWT applied to survivors of poliomyelitis (a neuromuscular condition with a musculoskeletal component), reproducibility was high; hence, test validity and interpretation were enhanced. The 6MWT distance was useful in elucidating the relation between impairment and a functional activity-namely, walking-in survivors of poliomyelitis.