Applied Anatomy of the Rectum and Anal Canal

Introduction

The rectum and anal canal are essential components of the digestive system, facilitating waste elimination. Understanding their vascular supply and lymphatic drainage is crucial for diagnosing and managing various medical conditions.

Vascular Supply of the Rectum and Anal Canal

Arterial Supply

• Superior rectal artery (branch of the inferior mesenteric artery) supplies the upper rectum.
• Middle rectal artery (branch of the internal iliac artery) supplies the mid-portion of the rectum.
• Inferior rectal artery (branch of the internal pudendal artery) supplies the anal canal.

Venous Drainage

• Superior rectal vein drains into the portal system.
• Middle and inferior rectal veins drain into the systemic circulation.

Lymphatic Drainage

• Upper rectum drains into the inferior mesenteric lymph nodes.
• Middle rectum drains into the internal iliac lymph nodes.
• Anal canal drains into the superficial inguinal lymph nodes.

Congenital Anomalies

Congenital abnormalities, such as anorectal malformations and rectal agenesis, can significantly impact bowel function and require surgical intervention.