In addition, since isometric exercises are done in a static position, they won't help improve speed or athletic performance. They can be useful, however, in enhancing stabilization â maintaining the position of the affected area â since muscles often contract isometrically to aid in stabilization.
Etiology. Most (85-95%) substernal thyroid masses represent benign goiter. Historically, goiters have generally occurred because of iodine deficiency, although this is now observed primarily in developing nations.
Substernal goiter remains a common consideration in the differential diagnosis of a mediastinal mass. Given. the potential for serious goiter-related complications as well as the inability to rule out associated malignancy, it has been our policy to treat all substemal goiters surgically over the past 20 years.