A study last month from the University of Iowa Hospitals and Clinics showed that during an eight-year period (2007-2015), about 65 percent of patients with knee pain related to osteoarthritis spent thousands of dollars on not-recommended, ineffective treatments—such as injections of hyaluronic acid and corticosteroids, and wearing braces and wedge insoles—before considering surgery.
Yet for people with knee or hip pain severe enough to keep them from doing activities they enjoy, surgery can provide immediate and long-term relief.
We spoke to Samuel Park, M.D., an orthopedic surgeon at Mission Hospital, and asked him to address common misconceptions about knee and hip surgeries.
Myth: Knee replacement surgery is only for athletes whose knees have given out.
Fact: “Knee surgery is for everyone with knee pain that interferes with their lives,” says Dr. Park, who also serves as Medical Director of Total Joint Replacements at Mission Hospital.
“Candidates for knee surgery are people who cannot walk more than six to 12 blocks without pain, who have difficulty sleeping because of the knee pain and difficulty doing everyday activities like going up and down stairs or getting in and out of the car,” he says. “When they think about doing an activity, they think about the knee pain more than the activity.”
The pain originates from osteoarthritis — in other words, wear and tear, he explains. In the knee, the end of the tibia bone meets the end of the femur, with cartilage in between that acts as a cushion. For people with osteoarthritis, this cushion has worn away, so the two bones rub against each other, causing irritation and pain, according to American Academy of Orthopedic Surgeons.
Myth: Knee surgery means the entire knee joint is replaced.
Fact: Most often only the surfaces of the knee bones that have been damaged by arthritis are replaced in knee surgery, explains Dr. Park. “It’s like putting a crown on a tooth — we resurface the bone, taking out 6 to 7 millimeters, and cap the surface with metal and plastic.”
Myth: Even when knee surgery is successful, it might have to be done again in a few years.
Fact: Most knee replacements (83 percent) last 20 years, according to Dr. Park.
Myth: The hip is a big joint, so it takes a long time to recover from hip replacement surgery.
Fact: Patients who’ve had knee or hip replacement generally stay in the hospital for one or two days, says Dr. Park, and they will be able to walk without assistance of a walker after two to four weeks. “In this surgery we take away four to five millimeters of bone, and cap it with a metal ball with a stem that goes down into the femur for support,” he explains.
Myth: Knee and hip surgeries require patients to have general anesthesia.
Fact: Not necessarily. These joint surgeries usually require only a regional anesthetic, says Dr. Park. “Patients are in a light sleep and when they wake up, they’re not as nauseated as if they’d had general anesthesia.”
Myth: Hip surgery is for older people.
Fact: Hip pain is mostly due to osteoarthritis and yes, many people develop it as they get older, says Dr. Park. He estimates that by 2030, the number of knee replacement surgeries will increase by 600 percent, and hip replacements by 300 percent.
But hip pain can also result from an accident or from a disease called avascular necrosis (AVN) in which blood supply to the bone has been interrupted.