Rub in tenosynovitis and perimyotenositis of trauma
There may appear rub in extension-flexion movement in the case of tenosynovitis. For example, when a patient with tendovagititis of flexor digitorum is doing extension-flexion movement of finger in examination, a snapping sound may be heard. When a patient with perimyotenositis is examined, a sound like twirling a hair, which is called crepitant rales, can be heard or felt. It often occurs when there is inflammatory exudation around the muscle tendon, usually in the extensor muscles of forearm, or quadriceps muscle of thigh, or Achilles tendon.