Self-Reported Functional Mobility, Balance Confidence, and Prosthetic Use Are Associated With Daily Step Counts Among Individuals With a Unilateral Transtibial Amputation

Background: Adults postamputation are not meeting physical activity recommendations. Physical activity is an important consideration in prosthetic prescription. The objective of this study was to determine if functional mobility, balance confidence, and prosthetic use are associated with physical activity among adults with a lower-limb amputation. Methods: This study recruited patients aged 18-85 years with unilateral transtibial amputations. The Cumulative Illness Rating Scale was used to determine comorbidity burden. Participants completed the Prosthetic Evaluation Questionnaire-Mobility Section, Activities-specific Balance Confidence Scale, and Houghton Scale of Prosthetic Use and wore a StepWatch monitor for 7 days to obtain daily step counts. Linear regression was used to evaluate relationships between each self-report measure and step counts after controlling for covariates, that is, sex, age, time since initial amputation, and comorbidity burden. Results: Forty-seven participants had >= 5 days of step data and were included in this analysis. The Prosthetic Evaluation Questionnaire-Mobility Section [mean (SD): 35.0 (9.6) points] and Activities-specific Balance Confidence Scale [79.2% (15.9%)] each explained 13% of the variance in step count [5491(4043) steps], whereas the Houghton Scale of Prosthetic Use [10.3 (1.2) points] explained 10% of the variance. Conclusion: Self-reported functional mobility, balance confidence, and prosthetic use predict short-term average daily step counts as determined from research-grade accelerometers.