Knee Pain: Causes by Location and When to See a Pain Specialist

Knee pain is best sorted out three ways: what set it off, how old you are, and — most useful of all — where in the knee it hurts. This page walks through knee pain by location, then covers the causes a pain specialist finds when the usual answers come up empty.

A quick tour of the knee

The knee is really three joints working together — where the thigh bone (femur) meets the shin bone (tibia), where the two lower leg bones meet, and where the kneecap rides. Between the bone ends sit rubbery shock absorbers (the menisci) that wear with age. Two crossed ropes in the center — the cruciate ligaments — hold the knee steady through bending and twisting, which is why they're classic sports injuries. Ligaments on each side (the collateral ligaments) add stability, fluid-filled sacs (bursae) cushion and lubricate, and muscle attachments ring the whole joint. Any of these can generate pain.

Pain all over the knee

Generalized knee pain suggests fracture, ligament tear, dislocation, arthritis (including gout), or infection. The most common by far is degenerative arthritis — the joint wears out, producing a grinding sensation, pain at the fully straight and fully bent positions, and a shrinking range of motion. Its pain typically worsens as the day goes on.

Pain in both knees

Pain in both knees points toward degenerative or rheumatoid arthritis, bursitis, meniscal wear, or calf muscle strain and cramps. A useful clue: rheumatoid arthritis pain is characteristically worse in the morning.

Pain by specific location

Back of the knee — usually muscle strains (the calf, hamstring, or plantaris muscles); rarely, a posterior cruciate ligament injury.

Inner knee (big-toe side) — often a torn or worn medial meniscus, from twisting the bent knee in sport or from age-related degeneration. The giveaway symptom is a knee that "locks up or gives way." Bursitis is also common here and responds well to a cortisone injection.

Outer knee — a lateral meniscus tear, tendinitis, or iliotibial band syndrome (frequent in runners).

Front of the knee — usually the kneecap, from inflammation of its surrounding bursae or ligaments. "Housemaid's knee" is front-of-knee pain and swelling from kneeling (scrubbing floors, tiling), and responds to a local injection.

What to expect at your exam

A good evaluation starts with the story of how the pain began, then a thorough exam of both the knee and the hip (hip problems refer pain to the knee), with attention to exactly where it's tender and how it responds to being pushed and pulled in different directions. Plain X-rays are standard; an MRI or arthroscopy follows if a ligament or meniscus tear is suspected.

Where a pain specialist comes in

A pain specialist usually enters the picture when the common problems have been ruled out or surgery hasn't helped. Two often-overlooked causes are worth knowing:

Nerve damage around the knee — for instance to the medial infrapatellar branch of the saphenous nerve, from trauma or surgery — is rare but frequently missed. It's felt as shooting or electric pain, and can be treated by injecting numbing medication and cortisone at the damaged nerve.

Complex regional pain syndrome (CRPS/RSD) — severe pain out of proportion to the injury, where even a light touch or cold air is excruciating — can follow even minor trauma, infection, or surgery. It needs prompt, specialized treatment (covered on our leg/foot pain page).

If your knee pain has outlasted the usual treatments, or surgery didn't resolve it, call Newport Pain Management at (949) 759-8400.