CEA test: Carcinoembryonic antigen test is to detect response to therapy in cancer patients, especially colon cancer, with normal range of less than 2.5 (less than 5 in heavy smokers). Note that a positive test may not always be indicative of cancer.
Os Trigonum Syndrome. An Os Trigonum is a small, extra bone found at the back of the ankle in approximately 5-10% of people. Often it goes completely unnoticed, not causing any problems.
Often it goes completely unnoticed, not causing any problems. However, when combined with an ankle injury or in athletes who sports require frequent ankle flexion e.g. ballet dancers and footballers, Os Trigonum Syndrome can develop causing pain and stiffness at the ankle.