1986 年 34 巻 3 号 p. 979-983
We reported a case of voluntary posterior dislocation of the elbow which occurred after simple traumatic dislocation.
A 10 years old boy, who had had the traumatic dislocation due to a fall, visited us at Goto Chuo Hospital complaining of dislocation of the left elbow. On examination, he could voluntarily dislocate his elbow at the position of 30° flexion and pronation of the forearm. Stress roentgenogram suggested the laxity of lateral collateral ligament. In electromyogram, discharge of the brachioradialis and triceps muscles was observed at the time of voluntary dislocation.
On this patient, we performed transplant of biceps tendon to the coronoid process and release of brachioradialis muscle at its origin. Five months after operation, instability of the elbow joint has disappeared. It may be considered that this voluntary dislocation of the elbow occurred by the activity of brachioradialis muscle under existence of the lateral collateral ligment laxity.