Extremity support apparatus

The invention provides an adjustable apparatus, which is removedly attachable to a medical emergency cot, gurney, wheeled stretcher or the like, and that functions to support and immobilize of an extremity of a human body during patient transport. The apparatus consists of a cot attachment member an extension pole assembly and an extremity support member and wherein certain combinations of relative movements of the extension pole assembly and the extremity support member allow the apparatus to be disposed and secured in positions that support an extremity of a patient lying on the emergency cot and wherein other combinations of relative movements allow the apparatus to be disposed and secured in a storage position. Certain embodiments of the apparatus are attachable to a chair for use in phlebotomy procedures.