Pain behind the knee is a frequent and often confusing complaint for many patients. While some may suspect a muscle pull, others worry about more serious concerns like blood clots or nerve issues. The truth is, the back of the knee is a compact space filled with nerves, blood vessels, tendons, and fluid pouches—making accurate diagnosis crucial.
In this blog, we’ll walk through the six most common causes of back-of-knee pain, how they’re evaluated, and effective non-surgical treatments that can help you recover safely.
1. Baker’s Cyst
A Baker’s cyst is a fluid-filled sac that forms at the back of the knee. It often appears when the knee joint is irritated due to arthritis, inflammation, or a meniscus tear. This fluid gets pushed backward, creating swelling or a balloon-like sensation. Common symptoms include tightness, swelling, or fullness—especially when bending the knee.
2. Hamstring or Calf Tendon Problems
The hamstring and calf muscles connect behind the knee. Overuse from running, squatting, or sports can strain or inflame these tendons. Pain typically feels sore or tight and worsens with activity. This is especially common in active individuals.
3. Knee Arthritis
While arthritis is typically associated with joint pain, it can also lead to fluid buildup in the back of the knee, potentially forming or worsening a Baker’s cyst. If you’re experiencing morning stiffness, clicking, or deep aching, arthritis could be the root cause.
4. Nerve-Related Pain
The tibial and peroneal nerves run through the back of the knee and can be compressed by issues like a Baker’s cyst or even a pinched nerve in the lower back. Nerve-related pain feels sharp, burning, electric, or tingling, and can also cause weakness or numbness down the leg.
5. Blood Vessel Problems
The popliteal artery and veins sit directly behind the knee. In rare cases, they can become narrowed or blocked. A DVT (deep vein thrombosis) is a serious medical emergency. Look out for sudden pain, swelling, warmth, or redness and seek immediate medical help.
6. Referred Pain from the Spine
Sometimes the pain doesn’t originate from the knee at all. A herniated disc or SI joint issue in the lower back can cause referred pain that mimics knee problems. This type of pain often travels down the leg and may feel identical to a true knee issue.
How We Diagnose the Cause
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Patient History: We listen to your symptoms—how the pain feels, when it started, and whether there’s swelling or nerve symptoms.
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Physical Examination: We evaluate your movement, strength, sensation, and reflexes to assess nerve or joint involvement.
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Imaging: Using musculoskeletal ultrasound or MRI, we examine tendons, cysts, fluid, or nerves in real time. If a blood clot is suspected, we refer for an emergency Doppler ultrasound.
Non-Surgical Treatment Options
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Physical Therapy & Exercises: Targeted rehab to improve strength and mobility.
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Anti-Inflammatory Diet: Focus on omega-3s, turmeric, and reduce sugar and red meat.
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Weight Management: Every pound lost reduces knee pressure significantly.
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Nerve Glides & Mobility Work: Especially helpful for nerve irritation.
Regenerative Medicine
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Prolotherapy: Injections of dextrose solution to strengthen irritated ligaments.
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PRP (Platelet-Rich Plasma): Uses your blood’s platelets to reduce inflammation and promote healing in tendons, joints, or nerves.
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Bone Marrow Stem Cell Therapy: For more advanced arthritis to support tissue repair.
Treatments to Avoid (Unless Absolutely Necessary)
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Steroid Injections: Can weaken tissue with repeated use.
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Radiofrequency Ablation: Burns nerves but doesn’t address root causes.
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Unnecessary Surgery: Especially for cysts or partial meniscus tears that respond well to rehab and regenerative care.
When to Seek Help
If the pain lasts more than a few weeks, worsens, or is accompanied by numbness, tingling, or swelling, it’s time to see a specialist. And if you suspect a blood clot, seek emergency care immediately.
Most cases of back-of-knee pain can be resolved without surgery using personalized, regenerative, and conservative treatments.
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