<prompt> Most common age group affected in thoracic outlet obstruction syndrome?10-25 years25-45 years45-65 years65 years  <response>: Answer- B. 25-45 yearsIt constitutes compression of subclan vessels andor brachial plexus between scalene muscles and first rib.Impoant causes are cemical rib and fibrous band from C, spinous process to first rib.Most common age group involved is 25-50 years females are more affected. 