Complete unilateral right-sided absence of the pectoralis major and serratus anterior muscles in an adult male cadaver of South Indian origin.

The unilateral complete absence of the pectoralis major and serratus anterior muscles in the absence of other anomalies is very rare. The complete absence of the pectoralis major and serratus anterior on the right side was observed during routine dissection of an elderly male cadaver of South Indian origin. Nodularity of the right fifth rib near the fifth costochondral junction was seen. The lateral pectoral and long thoracic nerves were present on the right side. Moderate right-sided disuse atrophy was noted in the pectoralis minor and the rotator cuff muscles due to a shoulder arthrodesis performed on that side. No abnormalities were noted on the left side. There was no family history of any upper limb anomalies suggestive of Poland's syndrome. The findings in the present case could be either due to a sporadic variant of Poland's syndrome or an isolated congenital unilateral absence of the pectoralis major and serratus anterior.