Spider veins can occur anywhere on the thighs, legs or ankles. Usually they appear in a network, fed by an underlying mid-size or reticular vein.
Spider veins aren’t something new that forms in our body—they are due to the stretching of the veins that lie near the skin surface that were previously too small to be seen. Once they’ve become stretched, these small veins hold more blood and can become visible to the naked eye. Spider veins take on many forms and can appear as individual thread-like streaks, or as vein clusters that can mimic the branches of a tree or a starburst pattern.
What factors contribute to the development of spider veins?
- Family History: If you have immediate family members who have spider veins, chances are that you may develop them as well.
- Trauma: Soft tissue injuries can often stimulate the formation of abnormal spider veins. This can happen as a result of surgery or injury.
- Medications: Female hormones such as estrogen and progesterone can cause spider veins to form. The most common medications include oral contraceptives, hormone replacement therapy, and infertility drugs.
- Occupation: Standing or sitting for long periods of time can worsen spider veins (teachers, nurses, flight attendants, hairdressers, sales clerks, etc. are very prone to developing spider veins.)
Spider veins can be seen on any part of the leg, as well as the face, chest, abdomen, back, or arms. It is thought that facial spider veins are caused by a combination of sun exposure and/or chronic skin inflammation, such as Rosacea.
Spider veins may be purely a cosmetic concern, or, they may be an indication that something more serious is affecting your vein circulation. When many spider veins are seen on the inside of the knee or around your ankle, the likelihood of a more serious vein problem is higher. In these patients, an ultrasound, which is a painless procedure that takes minutes to perform, can clearly determine whether the spider veins represent an underlying medical problem.