PT Orthopedic Clinical Specialist (OCS) Clinical Practice Exam

The Thessaly test is designed to detect meniscal pathology by loading and twisting the knee in a weight-bearing position. When the knee is slightly flexed and the leg is rotated while the patient bears weight, a positive result—pain or a discernible click along the joint line—indicates a meniscal tear. The combination of axial load with tibial rotation stresses the meniscus, revealing tearing or degeneration more than it does ligamentous injuries. This pattern is distinct from issues like ACL tears (which cause instability and positive Lachman or pivot-shift tests), lateral collateral ligament injuries (which show varus instability), or patellofemoral pain (which presents with anterior knee pain around the patella rather than joint-line pain with rotation). A positive Thessaly test therefore points to a meniscal tear.