Anatomy

Authors: Anne Herman Mosebo, MD, Julie Tastesen, MD, Magnus Balslev Avnstorp, MD

Anatomical landmarks

Umbilicus	Located at a horizontal line between and just above the ASIS (anterior superior iliac spine)1
Waist	The narrowest point of the torso. The umbilicus is usually located 1-4 cm below the natural waist1

Layers of the abdominal wall

When removing excess skin on the abdomen, the desired level to reach depends on the location on the abdomen. Starting from the xiphoid process the desired level to reach is superficial to the rectus fascia. Stay just above Scarpa’s fascia the last 5-7 cm above the lower incision. 

Scarpa’s fascia is a strong fibrous layer of connective tissue which covers the anterior abdominal wall and is located between the superficial and deep layers of subcutaneous abdominal fat.

Blood supply

Blood supply to the abdominal wall comes from major arteries and can be divided into 3 different zones (Zone I-III). There is a rich plexus between these systems that allows for collateral flow.¹ The three zones are as follows: 

Zone	Supplying arteries
Zone I	The deep superior/inferior epigastric arcade
Zone II	The superficial epigastric, superficial external pudendal and superficial iliac arteries
Zone III	Six lateral intercostal and four lumbar arteries

When performing an abdominoplasty, the cutaneous supply of zone I and a considerable 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 the abdominoplasty.¹

The blood supply of the skin and musculature of the midback comes from perforators arising from the posterior intercostal and lumbal arteries. These perforators have anastomotic connections.

The blood supply of the skin, soft tissue and musculature of the gluteal area comes from the superior gluteal and inferior gluteal artery which both arises from the internal iliac artery.²   

Nerve supply

The iliohypogastric and ilioinguinal nerve are sensory nerves innervating the area of the groin and medioventral part of the thigh. These nerves are located approximately 2 fingerbreadths below ASIS (anterior superior iliac spine). Disruption of these nerves will result in loss of sensation in this area.¹

Acknowledgements

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