Dear Mayo Clinic: Six years ago, at age 67, I had my right hip replaced. I’d been feeling fine until about eight weeks ago, when it started to hurt toward the front of my hip when I lift my right leg. The pain is quite significant — to the point where it hurts every time I get in my car or attempt to put on socks. What could be causing this to happen?

Answer: There are a number of possible reasons for the discomfort you’re experiencing. It might be a problem with the artificial joint, or you may have an infection. The pain also could be related to a condition called hip flexor tendinitis. To find out the underlying cause, make an appointment to see your surgeon to have your situation evaluated soon.

Hip replacement surgery involves removing the hip joint and replacing it with an artificial joint that typically consists of metal, ceramic and hard plastic. The implants used in hip replacements are made to resist corrosion and wear. For most people who undergo the surgery, hip replacement successfully relieves hip pain and restores hip function.

When, as in your situation, people have pain after the surgery, there’s often an underlying problem that can be diagnosed and effectively resolved if it’s treated promptly. It’s possible that you’ve developed an infection around the artificial joint. Many infections can be treated effectively with antibiotics. But a major infection near your artificial hip joint may require surgery to remove and replace the joint.

Another potential cause of your pain could be a loose implant. This can happen over time in some cases, but it’s not as common now as it used to be. Today’s technology makes a loose implant less likely than in the past, because many implants used now are designed to grow into the bone. If your implant has come loose, though, it’s important to have that identified and fixed as soon as possible. As an implant loosens, it tends to rub against the bone. And that can cause bone loss, making the joint more difficult to repair.

The pain also could be a result of hip flexor tendinitis, also known as psoas tendinitis. Tendinitis is an inflammation or irritation of a tendon. Tendons are the thick, fibrous cords that attach muscle to bone. In this case, the tendon that’s affected is the psoas — a tendon located in the hip joint that helps the joint move.

Psoas tendinitis often causes pain in the hip, groin and thigh. The pain of psoas tendinitis typically worsens when you lift your leg, or when you walk up steps or get up out of a chair. Patients consistently state that it hurts the most when getting in and out of a vehicle.

Physical therapy may help relieve tendinitis. An injection of corticosteroid medication around the tendon also can be used to reduce inflammation and relieve pain. If those treatments are not successful, surgery may be needed.

It’s important that you have your condition assessed as soon as possible to uncover the underlying cause of your hip pain. If you delay in seeking care, additional damage could occur within the hip joint, making treatment more difficult.

If possible, make an appointment for an evaluation with the surgeon who originally performed your hip replacement. If that isn’t an option, ask your health care provider to refer you to another surgeon, preferably one who has experience working with hip replacements.