Pain above the knee, behind the knee, and throughout the entire leg â combined with a bruise-like ache, burning sensation, difficulty walking, and pain even at rest/while sleeping â suggests a few important possibilities. First and most urgent to rule out: Deep Vein Thrombosis (DVT), a blood clot in the deep veins of the leg. DVT causes pain, heaviness, warmth, and sometimes swelling in the entire limb and needs immediate evaluation because it can be dangerous. Second possibility is nerve-related pain â compression of the sciatic nerve (sciatica) from the lower back can cause burning pain running from the thigh down to the knee and below, and worsens at rest/night. Third: a musculoskeletal problem such as a knee ligament or meniscal issue, or muscle strain. The fact that you have pain at night and across the entire leg (not just one spot) makes nerve or vascular causes more likely than a simple local muscle problem.
Next Steps
Please see an Orthopedic surgeon or a General Physician promptly. If your leg is also swollen, warm, or red, go to an emergency department today to rule out DVT â do not delay. Do not self-medicate with pain pills alone without a diagnosis. Please consult me directly on Practo for a detailed evaluation.