Abduction Prevention

Healthcare Professionals Guidelines on Prevention of and Response to Infant Abductions, 6th ed. National Center for Missing Exploited Children, March 2000. 

From the AP position the knees are flexed to form an angle of 90 , the leg under examination is then externally rotated until the whole of the lateral aspect of the femora is in direct contact with the film/table surface. The pelvis will often lift on the unaffected side to allow this position to be obtained. Foam pads applied under the lifted portion of the pelvis will assist in maintaining the position, as will asking the patient to keep the unaffected foot flat on the table surface. It is important to abduct the unaffected leg sufficiently to prevent the side under examination to be obscured (Fig. 2.4). 

To prevent impingement, the lower end of the humerus has two fossae, one at the front and one at the back. This gives the human elbow a range of 0 -142° of flexion extension with 5 of further passive flexion. About 9 of abduction and adduction exist in the ulno-humeral joint. This range of movement is essential to complete the full arc of pronation and supination. 

The humerus impinges on the acromial arch at 90 degrees. To prevent impingement and permit abduction to 180 degrees, the scapula must rotate. 

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