A case of individual variation of the rhomboid muscles

Abstract

During the routine gross anatomic dissection of a Turkish male cadaver; a variation of rhomboid muscles was observed on the left side. There were two rhomboid minors and three rhomboid majors coursing under the trapezius muscle. The origins of the upper and lower rhomboid minor muscles were C5, C6 and C7 vertebrae, respectively. Their insertions were to medial border of scapula, to upper part and to lower part of the spine of scapula, respectively. The origins of the upper, middle and lower rhomboid majors were C7, T1-T3 and T4-T5 vertebrae, respectively. Their insertions were to the 2/3 most inferior part of the medial border of scapula, from superior to inferior in sequence. In the examination of the literature, we could not observe such a variation of these muscles. In surgical procedures these types of variations have a clinical importance for intrathoracic muscle flap transfers and in cases with the paralysis of trapezius muscle.