Fig. 1
(A) A largeinflatable raft (flyfish) is connected to a motorboat by rope. When the motor boat increases its speed, the flyfish floats over the water.
(B) Flyfish riders hold on to strips in a position of 90° flexion of the elbow and 45° external rotation and mild degrees of abduction of the shoulder.
Fig. 2Anteroposterior radiographs show distal 1/3 humerus spiral fracture with butterfly fragment in all cases.
Fig. 3
(A) Preoperative radiograph shows distal 1/3 humerus spiral fracture with butterfly fragment.
(B) Immediate postoperative radiograph shows interfragmentary fixation with 1 cortical screw and plate fixation.
(C) Ten weeks after surgery, complete bone union is noted on anteroposterior radiograph.
Fig. 4Internal rotator of the arm and flexor of the elbow may generate twisting and axial compression forces on the humerus. These forces may cause the humeral spiral fracture with butterfly fragment.