Anatomy

Authors: Magnus Avnstorp Balslev, MD., Mette Ydo Jacobsen, Med. Stud., Anne Mosebo, MD, Julie Tastesen, MD and Emir Hansanbegovic, MD

Layers of the abdominal wall

The dissection should go no deeper than the muscle fascia and just superficial to the abdominal rectus muscle (medially) and external oblique muscle (laterally).

Blood supply

The blood supply to the abdominal wall comes from major arteries and can be divided into 3 different zones (Zone I-III). Zone I is supplied by the deep superior/inferior epigastric arcade. Zone II by the superficial epigastric, superficial external pudendal, and superficial iliac arteries. Zone III (the flanks) is supplied by six lateral intercostal and four lumbar arteries. There is a rich plexus between these systems that allows for collateral flow.

When performing an abdominoplasty, the cutaneous supply of zone I and sizeable large part of zone II will be disrupted. Therefore, it is crucial for the survival of the abdominal flap to maintain blood supply from zone III. Any preoperative scars (from previous surgery) or intraoperative ligation of lateral intercostal/lumbar perforators might jeopardize flap survival and thus the outcome of abdominoplasty.

Nerve supply

Sensory innervation of the abdominal wall: Anterior and lateral cutaneous branches from the intercostal nerves VIII-XII.¹

Motoric innervation of the abdominal wall: Oblique and transversus abdominis muscle are innervated by branches from lower thoracic and lumbar dorsal nerves. The rectus abdominis muscle is innervated by branches from the intercostal nerves V-XII.¹

Acknowledgements

Illustrators: Emma Tubæk Nielsen, Med. Stud. and Anne Mosebo, MD