Prosthetic Intervention Effects on Activity of Lower-Extremity Amputees

Klute GK, Berge JS, Orendurff MS, Williams RM, Czerniecki JM. Prosthetic intervention effects on activity of lower-extremity amputees.ObjectiveTo investigate the effect of prosthetic interventions on the functional mobility of lower-extremity amputees.DesignCrossover with repeated measures.SettingHousehold and community environment.ParticipantsTwelve transtibial and 5 transfemoral amputees.InterventionsFor transtibial amputees, shock-absorbing versus rigid pylons. For transfemoral amputees, C-Leg versus Mauch SNS knees.Main Outcome MeasuresDaily activity level (step count) and duration (minutes of activity).ResultsPylon type had no effect on the daily activity level or duration of transtibial amputees. Knee type had no effect on the daily activity level or duration of transfemoral amputees. Transtibial amputees were more active on weekdays (3079±1515 steps/d) than weekends (2386±1225 steps/d) (P=.007). In general, lower-extremity amputees perform numerous short-duration bouts of activity (1−2min) consisting of fewer than 17 steps/min, but activities of more than 15 minutes in duration were relatively rare (<1 per day).ConclusionsIntervention had no effect on amputee activity level and duration. Higher weekday activity levels of transtibial amputees suggest their vocational activities are more demanding than recreational activities. The fitting, alignment, and design of prosthetic components should be optimized for 1 to 2 minute bouts of activity consisting of only a few dozen steps.