21 men and 59 women ( mean age , 45.2 years ) presenting with lateral epicondylitis were randomised to receive either autologous blood injection ( 2 ml of autologous venous blood mixed with 1 ml of 2 % prilocaine hydrochloride ) or corticosteroid injection ( 1 ml of 40 mg methylprednisolone acetate mixed with 1 ml of 2 % prilocaine hydrochloride ) given by a single physician .