Healthy Geezer

Q. I’m considering having a hip replaced. What are the odds that this operation will work?

The American Academy of Orthopaedic Surgeons says joint replacement surgery is successful in more than nine out of 10 people. And replacement of a hip or knee lasts at least 20 years in about 80 percent of those who have the surgery.

In the procedure, an arthritic or damaged joint is removed and replaced with an artificial joint called a “prosthesis.” Artificial joints are medical devices, which must be cleared or approved by the FDA before they can be marketed in the United States The goal of surgery is to relieve the pain in the joint caused by the damage done to cartilage, the tissue that serves as a protective cushion and allows smooth, low-friction movement of the joint. Total joint replacement is considered if other treatment options will not bring relief.

In an arthritic knee, the damaged ends of the bones and cartilage are replaced with metal and plastic surfaces that are shaped to restore knee function. In an arthritic hip, the damaged ball and socket of this joint are replaced by a metal ball and plastic socket. Several metals are usually used, including stainless steel, alloys of cobalt and chrome, and titanium. The plastic material is durable and wear-resistant polyethylene.

The two most common joints requiring this form of surgery are the knee and hip, which are weightbearing. But replacements can also be performed on other joints, including the ankle, foot, shoulder, elbow and fingers.

After total hip or knee replacement, you will often stand and begin walking the day after surgery. Initially, you will walk with a walker, crutches or a cane. Most patients have some temporary pain in the replaced joint because the surrounding muscles are weak from inactivity and the tissues are healing, but it will end in a few weeks or months.

Exercise is an important part of the recovery process. After your surgery, you may be permitted to play golf, walk and dance. However, more strenuous sports, such as tennis or running, may be discouraged.

There can be complications from joint replacement surgery. These include infection, blood clots, loosening of the prosthesis, dislocation of the joint, excessive wear, prosthetic breakage and nerve injury. There are remedies for all of these complications, but sometimes the correction will take more surgery.

Surgeons are refining techniques and developing new ones such as minimalincision surgery. In this type of surgery, smaller incisions are used. Minimal incisions reduce trauma, pain and hospital stays. Not all patients are candidates for minimal-incision surgery.

There is a surgical alternative to total hip replacement. It’s called hip resurfacing. The primary difference in hip resurfacing is that the surgeon doesn’t remove the ball at the top of the thigh bone. Instead, the damaged ball is reshaped, and then a metal cap is anchored over it.

Hip resurfacing, unlike hip replacement, preserves enough bone to permit a total replacement if it is necessary later. Resurfacing is not recommended for patients with osteoporosis, a disease that makes bones porous and vulnerable to fractures. Some health-care experts advise getting a replacement hip joint, not a resurfacing, if you are older than 65.

Fred Cicetti is a freelance writer who specializes in health. He has been writing professionally since 1963. Before he began freelancing, he was a reporter and columnist for three daily newspapers in New Jersey. If you would like to ask a question, write to fred@healthygeezer.com.