Sato Y, Kosters A, Rieder F, et al. - The present study was conducted to reexamine these ultrasound data to diagnose if brightness mode ultrasound imaging reflects pathological changes of the patellar tendon after total knee arthroplasty (TKA). Researchers assigned 28 individuals with post unilateral TKA to an intervention group or control group. The intervention group had undergone a 12-week skiing program. They obtained patellar tendon mechanical properties by combining isometric dynamometry, ultrasound imaging, and electromyography in the operated knee and non-operated knee. They assessed luminosity ratio (LR) applying echo intensity in a relaxed and maximally loaded phase. After TKA, patellar tendon LR is reduced along with degenerative change. After TKA,ultrasound imaging offers a promising metric to acquire in vivo patellar tendon pathological evaluation.