Rectus Sternalis: A Case Report
Abstract
The sternalis is an anatomical variant of anterior chest wall muscle. It occurs either unilateral or bilateral. It lies in the anterior chest
wall, superfi cial to the sternal origins of the pectoralis major muscle. The sternalis usually courses longitudinally adjacent to the
sternum and does not cross the midline. In the Department of Anatomy, during routine dissection of thoracoabdominal region of
a 49-year-old male, a distinct, separate fusiform muscular mass about 12 cm long was found in the left hemithorax, covered by
superfi cial fascia and located anterior to the pectoralis major muscle. The details are given in this case report. There is a lot of debate
on the origin of the muscle. This muscle can be misdiagnosed on routine mammography as a breast mass. It can play an important
role in reconstruction fl ap surgeries. Such anatomical variation should be kept in mind during surgical procedures and diagnosis.
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