Design: Double blinded, Randomized control trial.

Methods: 50 osteoarthritic patients will be evaluated to be allocated after they match the inclusion criteria then randomized to two groups, group A for Phonophoresis using Honey as coupling media with conventional physical therapy program, group B for ultrasound with regular gel as a coupling media with conventional physical therapy. Outcome measures: the primary outcome measure will be the thickness of the cartilage will be measured using diagnostic ultrasound, the secondary outcome measure will be knee pain measured by the visual analog scale (VAS) and Western Ontario and McMaster Universities OA Index (WOMAC) pain subscale, also functional mobility which will be measured using the stiffness and physical function subscales of the total WOMAC. All will be measured 1 day before starting the procedures and after 4 weeks of the intervention 3sessions/week.