114 patients with knee osteoarthritis were randomized to receive 12 days of focused low-intensity pulsed ultrasound therapy (n=57) or pulsed shortwave diathermy (n=57). The primary outcome of interest was functional capacity as measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and associated sub-scores (pain; physical function; stiffness). Secondary outcomes of interest included Numeric Rating Scale (NRS) pain scores, timed up-and-go test, range of motion, global rating of changes scores, and adverse events. Outcomes were assessed after the completion of treatment, and at 12 weeks and 24 weeks follow-up. Results revealed significantly better WOMAC scores and sub-scores, NRS scores, global rating of change scores, range of motion, and timed up-and-go test scores in the focused low-intensity pulsed ultrasound therapy group at 12 days (post-treatment). At 12 and 24 weeks, WOMAC total scores and NRS scores were also in favor of the focused low-intensity pulsed ultrasound therapy group.