Following ethics approval by the University of Manitoba and the Winnipeg Regional Health Authority, 44 participants will be recruited for the study. During the intake session, subjects will complete informed and assent consent, participant information and knee demographic forms. A radiographic report of the knee confirming that the subject is skeletally immature will be obtained from the referring orthopedic surgeon or performed at the Pan Am clinic. For only the ACL-injured subjects, a clinical examination diagnosis and KT-1000 test will confirm the injury. Anthropometric data, such as age, height, weight, range of motion, leg circumference and the pubertal maturation observation scale (PMOS), will be collected. All subjects are required to pass the standardized screening protocol prior to continuing with the testing procedures.