How to Distinguish Between Internal and External Hemorrhoids?

Both internal and external hemorrhoids belong to the category of hemorrhoids, and they can be mainly distinguished by their location and symptoms.

1. Location

Internal hemorrhoids are formed due to pathological changes in the supporting structures of the anal cushions, venous plexuses, and arteriovenous anastomoses, leading to congestion, hyperplasia, hypertrophy, and displacement of the anal cushions. Internal hemorrhoids are located above the dentate line, covered by mucosa, and commonly found on the left side, right anterior, and right posterior aspects of the lower rectum.

External hemorrhoids are formed by the pathological dilation of subcutaneous venous plexuses or hyperplasia of connective tissue distal to the dentate line, located below the dentate line and covered by anal canal skin.

2. Symptoms

The main clinical manifestations of internal hemorrhoids are rectal bleeding and protrusion of hemorrhoidal masses. Intermittent post-defecation bleeding of fresh blood is common, and internal hemorrhoids can protrude outside the anus when they progress to the second or third stage. The protruded hemorrhoidal masses can initially return spontaneously after defecation but gradually increase in size and become difficult to reset spontaneously, requiring manual replacement. Internal hemorrhoids are painless unless complicated by thrombosis, incarceration, or infection, and some patients may experience constipation.

The main clinical manifestations of external hemorrhoids are anal discomfort, wetness, and impurity, sometimes accompanied by itchiness. Connective tissue external hemorrhoids (skin tags) and inflammatory external hemorrhoids are common, and acute thrombosis can cause severe anal pain, known as thrombosed external hemorrhoids.