In addition to patient reported outcome measures, accelerometers may provide useful information on the outcome of sarcoma patients treated with limb salvage. The StepWatch (SW) Activity Monitor (SAM) is a two-dimensional accelerometer worn on the ankle that records an objective measure of walking performance. The purpose of this study was to validate the SW in a cross-sectional population of adult patients with lower extremity sarcoma treated with limb salvage. The main outcome was correlation of total steps with the Toronto Extremity Salvage Score (TESS). In a sample of 29 patients, a mean of 12 days of SW data was collected per patient (range 6-16), with 2767 average total steps (S.D. 1867; range 406-7437). There was a moderate positive correlation between total steps and TESS (r=0.56, P=0.002). Patients with osseous tumors walked significantly less than those with soft tissue sarcoma (1882 versus 3715, P<0.01). This study supports the validity of the SAM as an activity monitor for the objective assessment of real world physical function in sarcoma patients.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging