Musculoskeletal tissue injury and disease in the lower extremities are commonly experienced by many people around the world. In many sports anterior cruciate ligament (ACL) rupture is a frequent and debilitating injury (Cochrane et al., 2006). Patellofemoral pain (PFP) is one of the most often reported knee disorders treated in sports medicine clinics (Devereaux and Lachmann, 1984), and is a common outcome following knee replacement surgery for osteoarthritis (Smith et al., 2004). Osteoarthritis (OA) is one of the most common musculoskeletal diseases in the world (Brooks, 2006), with the knee and hip the most often affected joints (Brooks, 2006). All of these musculoskeletal conditions are associated with large personal and financial cost (Brooks, 2006).