What causes net-like red patterns on the knees, and what should be done about it?

Net-like red patterns on the knees may result from poor local blood circulation, skin exposure to cold or heat stimuli, allergic purpura, keratosis pilaris, or lower limb varicose veins. Improvements can be achieved by enhancing circulation, taking protective measures, and medical treatment. If the patterns spread, or are accompanied by itching, pain, or ulceration, prompt medical attention is necessary.

1. Poor local blood circulation: Prolonged sitting or standing can cause blood to pool around the knee area, leading to dilated blood vessels and net-like patterns, which may become more noticeable when exposed to cold. It is recommended to move the knees moderately and apply warm compresses with a heated towel to improve blood flow and relieve symptoms.

2. Skin exposure to cold or heat stimuli: Sudden changes in temperature can cause abnormal constriction or dilation of blood vessels, resulting in temporary net-like red patterns. Avoid rapid temperature changes around the knees, maintain warmth, and minimize alternating cold and heat exposure to the skin.

3. Allergic purpura: Vascular inflammation triggered by infection or allergies can lead to purplish-red net-like or dot-like patterns on the knees, possibly accompanied by mild tenderness. Under medical guidance, medications such as loratadine syrup, vitamin C tablets, and rutin tablets may be used to alleviate symptoms.

4. Keratosis pilaris: Abnormal keratin metabolism causes redness around hair follicles, forming fine net-like patterns with a rough texture upon touch. Patients may use tretinoin cream, urea ointment, or salicylic acid ointment under medical supervision to relieve discomfort.

5. Lower limb varicose veins: Malfunctioning venous valves impair blood return, causing net-like dilated vessels around the knees, which worsen after prolonged standing. As directed by a physician, patients may use medications such as diosmin tablets, horse chestnut seed extract (e.g., Venoruton), and wear medical compression stockings to improve symptoms.

Maintain clean and moisturized skin around the knees, avoid frequent friction or scratching, engage in moderate gentle exercises like walking and knee flexion/extension, maintain a balanced diet rich in vitamins, and ensure proper warmth to prevent cold exposure—supporting overall skin health and stability.