What could be the reason for numbness and a burning sensation at the back of the thigh in an 18-year-old?

Hello,

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I have read your query and understand your concern. First of all, you need to do an X-ray through which we can get confirmation of what the exact cause is. It might be a postural deformity of the spine. I suggest you avoid doing cartwheels for some days now. Lie flat on the bed, place a pillow under your lower back and try to press down the pillow with your lower back. Apply hot water bag when necessary. Lie on your back, and place a towel behind the numb leg. Hold both the edges of the towel with your hand and try to pull your leg towards your body. You can feel a stretch at the back of the leg. Repeat 15 times twice daily. It should be slow and not exert. Investigations to be done. Do X-ray as soon as possible. Regarding follow-up do X-ray as soon as possible and post us back with all the reports. Regarding preventive measures, avoid extension and spine rapid movements. I hope this helps. Regards.