Hip pain extending all the way to the knee can be excruciating, leaving you searching for answers and relief. There are many potential reasons for your discomfort. The hip joint is one of the largest ball-and-socket joints in the body and plays an important role in supporting body weight and movement. The pain may be due to a strain or injury to the muscles, tendons, or ligaments around the hip. Arthritis or joint disease may even be to blame. Sometimes, radiating hip pain doesn’t originate in the hip area at all. In fact, it could be due to a pinched nerve in the lower back or another type of nerve pinched. Here are five common causes of hip pain radiating from the leg to the knee:

Hip Labrum Tear

A labral tear is an injury to the tissue in the hip that holds the ball and socket together. A hip labrum tear can cause a variety of symptoms, the most common of which is pain in the front of the hip or groin area, which may extend down to the knee.

This pain develops gradually, is usually dull, and intensifies with walking, running, or spinning. In addition to pain, a hip labrum tear may result in a reduced range of motion in the hip joint and a feeling that the hip joint is locked.

Hip Osteoarthritis

Osteoarthritis is a degenerative joint disease in which excessive wear and tear on the joints over time can lead to pain and stiffness in the hips. As we age, the cartilage that cushions joints begins to degrade, causing bones to rub against each other.

This friction can cause osteoarthritis pain that can radiate to the front of the thigh and sometimes the knee.

Hip Bursitis

Hip bursitis is inflammation of the bursa, the fluid-filled sac that cushions the hip joint. Although the pain begins in the hip, it may radiate from the outer thigh to the knee. You may also notice some swelling and warmth in the affected area. Discomfort can range from severe to dull pain.

Iliotibial Band Syndrome

Soreness on the outside of the knee may be caused by iliotibial band syndrome. The iliotibial band is a thick band of fibrous tissue that runs along the outside of the leg. It starts at the hip and extends to the outside of the shin, just below the knee joint.

ITB syndrome can affect one or both knees. The discomfort is often described as a painful burning sensation that extends from the thigh up to the buttocks. You may experience this type of pain during exercise, especially running. It’s usually worse right after the foot hits the ground, and may only show up toward the end of your workout.

As your condition worsens, your pain may start earlier and last longer after you stop exercising.

Sciatica

Sciatica is caused by irritation of the sciatic nerve. The sciatic nerve is a large nerve that runs from the lower back through the buttocks and down the back of the leg. Discomfort may start in the buttocks and radiate down the back of the buttocks to the front, back, or sides of the legs.

Sciatica most commonly occurs when a herniated disc or overgrowth of the bone puts pressure on the nerve. Pressure, irritation, or injury to the sciatic nerve can cause pain, numbness, or tingling.

What to do if you have radiating hip pain

You should see your doctor if your hip pain is severe, persists for more than a few days, or worsens. To get an accurate diagnosis and create a pain relief plan, your doctor may complete a physical exam and tests such as blood tests, X-rays, CT scans, or MRIs.