[Electromyographic examination of the femoral muscles in hemophilic effusion in the knee-joint and in irritated conditions of the knee-joint (author's transl)].

In ten patients with acute effusion in the knee-joint due to hemophilia, or with chronic knee-joint affection, the maximal isometric contraction of the M. vastus medialis and lateralis and of the M. rectus femoris was measured by electromyography. Measurements were taken before and after puncture of the effusion, or before and after intraarticular injection of a local anesthetic. In all examined patients, the contraction tests were performed below the pain threshold. The proportionate share of energy of the quadriceps muscle was considerably enhanced by reducing the intraarticular pressure and injecting a local anesthetic. This increase differs, depending on the state of the knee-joint affection.