Internal rotation of the knee
The knee joint (Articulatio genus) is a composite joint consisting of the femur, kneecap and tibia and is one of the hinge joints. More precisely, the knee joint consists of the patellar joint, which is formed by the femur with the kneecap, and the popliteal joint, which is formed by the femur and tibia. At the back of the knee joint, in the popliteal fossa (Fossa poplitea), numerous important blood vessels, nerves and lymphatic pathways run through the knee.
The knee joint is stabilized and secured by numerous ligaments and muscles. The most important internal rotators in the knee are the musculus gracilis, the musculus semimembranosus and the musculus semitendinosus. As a pivot/ hinge joint, the knee joint is capable of internal and external rotation in the flexed state.
The degrees of freedom for the knee joint are Bending approx. 120-150°, stretching up to approx. 10°, internal rotation of 10° (when the knee is bent) and external rotation of 30-40° (in the bent state).The internal rotation in the knee can be checked using the Steinmann I sign.
Here, the examiner holds the patient’s leg and bends it by 90° in the knee and hip. He then performs an internal rotation and an external rotation. A painful internal rotation of the knee usually indicates damage to the lateral meniscus.
Internal rotation of the ankle
The ankle joint consists of several partial joints. The two largest subjoints are the upper and lower ankle joint. Together they form a functional unit and are called Articulatio cylindrica.
The upper ankle joint is one of the hinge joints, and allows the foot to be raised (dorsiflexion) and lowered (plantar flexion), and to a lesser extent, to rotate internally and externally. An inward (pronation) and outward (supination) rotation of the foot is also possible. Only two movements are possible in the lower ankle joint – eversion (lifting the outside of the foot) and inversion (lifting the inside of the foot).
