Congenital Partial Absence of Trapezius with Variant Pattern of Rectus Sheath

  • Sarika Rachel Tigga Mail Department of Anatomy, Esic Medical College and Hospital, Rohtak University, Delhi, India.
  • Preeti Goswami Department of Anatomy, Azad Medical College, Delhi University, New Delhi, India.
  • Jugesh Khanna Department of Anatomy, University College of Medical Sciences, Delhi, India.
Congenital variations, Rectus sheath, Trapezius, Transversus abdominis


Musculocutaneous pedicled/ free flaps are an essential prerequisite for reconstructive surgery. Amongst the trunk muscles commonly harvested for flaps, the trapezius and rectus abdominis provide satisfactory coverage for cranial and trunk defects. unilateral/ bilateral or partial congenital absence of trapezius muscle is well documented and may result in muscular imbalances compromising posture and limb movements. During routine cadaveric dissection, we encountered a case of bilateral partial absence of occipital part of the trapezius muscle. Concurrently, the ventral abdominal musculature displayed the aponeurosis of transversus abdominis muscle solely forming the posterior wall of the rectus sheath. These conjointly occurring anomalies advocate a compensatory strengthening of the anterior wall of rectus sheath in response to the congenital absence of occipital part of the trapezius, probably to counteract the postural instability. The present study focuses on recognition of compensatory mechanisms resulting from congenital variations as identification of such processes may prevent chronic debilitating conditions.


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How to Cite
Tigga SR, Goswami P, Khanna J. Congenital Partial Absence of Trapezius with Variant Pattern of Rectus Sheath. Acta Med Iran. 54(4):280-282.
Case Report(s)