Reliability, Concurrent Validity and Minimal Detectable Change of the Step Up and Down Test in Patients With Total Knee Arthroplasty

Step Up and Down Test In the StUD test, the patient completes maximum number of step-up-down repetitions in 15 seconds. Starting from a standing position, the participant took a full step up, leading with the test leg, then the non-testing leg, until both knees were fully extended and both hips were at least in neutral extension. In order to stress the testing limb concentrically and eccentrically, the participant stepped off the step first with the non-testing limb, then the testing limb. The patient was asked to repeat for 15 seconds as quickly as possible. The physical therapist stood to the side of the step for safety and so that he/she could observe the technique and ensure that the participant came to a full step up and down during the test.