Hip replacement surgery is generally safe, but like all surgery it carries real risks you should understand before the procedure

Hip replacement has a strong track record—most people recover well and regain mobility they lost to arthritis or injury. The surgery itself has been refined over decades, and hospitals perform hundreds of thousands each year in the United States. That said, complications do happen. The most common ones are blood clots, infection, and dislocation of the new joint. Serious complications occur in a small percentage of cases, but they are possible, and knowing what they are helps you make an informed decision with your surgeon.

Your personal risk depends on your age, overall health, whether you have other medical conditions, and the surgeon's experience. A 55-year-old in good health faces different odds than an 85-year-old with diabetes and heart disease. This guide explains the real risks, what hospitals do to prevent them, and what warning signs to watch for after surgery.

Key Takeaways

  • Blood clots in the leg or lung occur in roughly 1 to 2 percent of hip replacement patients, but hospitals use blood thinners and compression devices to reduce this risk.
  • Infection happens in fewer than 1 percent of cases when antibiotics are given before surgery, but deep infections can require a second operation.
  • The new hip can dislocate if you move the joint beyond its safe range in the first weeks after surgery, which is why physical therapists teach specific movement restrictions.
  • Nerve or blood vessel injury during surgery is rare but possible, and some patients experience temporary or lasting numbness or weakness.
  • Your surgeon should discuss your specific risk factors before the operation so you understand what applies to your situation.

Blood Clots: The Most Common Complication

Blood clots form in the legs of roughly 1 to 2 out of every 100 hip replacement patients, even with prevention measures in place. The surgery itself—cutting tissue, handling the bone, and lying still during recovery—creates conditions where clots can form. A clot that stays in the leg causes swelling and pain. A clot that breaks loose and travels to the lungs (called a pulmonary embolism) is life-threatening and requires emergency care.

Hospitals reduce this risk in several ways. You receive blood-thinning medication, usually starting before surgery and continuing for weeks afterward. You wear compression stockings or use a sequential compression device—a sleeve that inflates and deflates to push blood through your legs. You are encouraged to move your feet and ankles even while in bed, and to get up and walk as soon as possible after surgery. Despite these steps, clots still occur in some patients.

After you go home, watch for calf swelling, warmth, redness, or sharp pain in one leg. Shortness of breath, chest pain, or a rapid heartbeat can signal a clot has reached your lungs. Report any of these to your doctor or go to an emergency room when ready. The longer you wait, the greater the risk.

Infection: Rare but Serious

Surgical site infection occurs in fewer than 1 percent of hip replacements when antibiotics are given before the incision is made. The surgery creates an open wound, and bacteria can enter during the procedure or in the days after. A surface infection causes redness, warmth, and drainage at the incision. A deep infection reaches the joint itself and is much more serious.

Hospitals use sterile technique, antibiotic-coated instruments, and laminar airflow operating rooms to keep bacteria out. You receive intravenous antibiotics before surgery and sometimes for a day or two after. The surgical team covers the incision with a sterile dressing that you keep dry and clean at home.

If you develop fever, increasing pain, swelling that does not improve, or pus or foul-smelling drainage from the incision, contact your surgeon right away. A deep infection may require a second surgery to clean out the joint and sometimes to remove and replace the implant. This is why reporting signs early matters—early treatment can sometimes prevent the need for another operation.

Dislocation: Why Movement Restrictions Matter in Early Recovery

The new hip joint can slip out of its socket if you bend or rotate your hip too far in the first weeks after surgery. This happens in roughly 1 to 3 percent of patients and is more common in the first few months. A dislocated hip is painful and requires when ready medical attention—the joint must be put back in place, usually in an emergency room.

Your physical therapist will teach you specific positions to avoid: do not bend your hip more than 90 degrees, do not cross your legs, and do not rotate your leg inward. These restrictions feel awkward at first, but they protect the healing tissues around the joint. You use a pillow between your legs when lying down and a raised toilet seat to keep your hip from bending too far. Most people can gradually return to normal movement after six to eight weeks as the tissues heal and tighten around the implant.

If you feel a sudden pop, severe pain, or notice your leg looks shorter or turned outward, the hip may be dislocated. Go to an emergency room or call 911. Do not try to move the leg or put weight on it.

Nerve and Blood Vessel Injury

During surgery, the surgeon works around nerves and blood vessels near the hip. Injury to these structures is uncommon—it happens in fewer than 1 percent of cases—but when it occurs, the effects can be temporary or lasting. Nerve injury may cause numbness, tingling, or weakness in the leg or foot. Blood vessel injury can cause bleeding or reduced blood flow to the leg.

Most nerve injuries improve on their own within weeks or months as the nerve heals. Some cause permanent numbness in a small area of skin, which is usually tolerable. Serious nerve injuries that cause significant weakness are rare. Your surgeon's experience and the approach used (anterior, lateral, or posterior) can affect the risk of nerve injury, so discussing this with your surgeon beforehand is worthwhile.

After surgery, report any new numbness, tingling, or weakness that does not improve within a few days. Severe swelling, coldness, or color changes in the leg can signal a blood vessel problem and need when ready attention.

Implant Loosening and Wear

Hip implants are designed to last 15 to 20 years or longer, but they do not last forever. Over time, the implant can loosen from the bone or the plastic liner can wear down. Loosening usually develops slowly and causes increasing pain and limping. Wear of the plastic can release tiny particles that trigger inflammation and bone loss around the implant.

How long an implant lasts depends on your age at surgery, your activity level, and the quality of the implant itself. A 50-year-old who is very active may wear out an implant faster than a 75-year-old with limited activity. Your surgeon will discuss the expected lifespan of the specific implant being used. If loosening or wear occurs, revision surgery—replacing the worn or loose parts—may be needed. This is a more complex operation than the first replacement.

Anesthesia Risks

Hip replacement requires general anesthesia or regional anesthesia (spinal or epidural). Both carry risks, though serious complications are uncommon in healthy patients. General anesthesia can cause nausea, vomiting, and in rare cases, awareness during surgery or breathing problems. Regional anesthesia can cause temporary numbness or weakness below the injection site and rarely causes nerve damage.

Your anesthesiologist will review your medical history, current medications, and any previous anesthesia problems before surgery. Tell them about any allergies, sleep apnea, or difficulty with anesthesia in the past. Patients with heart disease, lung disease, or uncontrolled diabetes face higher anesthesia risk and need careful monitoring. The anesthesia team watches your heart rate, blood pressure, oxygen level, and breathing throughout the procedure.

Who Is at Higher Risk

Certain conditions increase the chance of complications. Obesity puts extra stress on the new joint and increases the risk of blood clots and infection. Diabetes slows wound healing and raises infection risk. Heart disease and lung disease make anesthesia riskier. Osteoporosis can make it harder for the implant to anchor securely to bone. Advanced age alone is not a barrier—many people in their 80s and 90s have successful hip replacements—but age combined with other conditions does increase risk.

If you have any of these conditions, discuss them with your surgeon before scheduling surgery. Some risks can be reduced by losing weight, controlling blood sugar, or treating heart or lung problems before the operation. Your surgeon may recommend delaying surgery until your health is optimized, or may proceed with extra precautions in place.

Frequently Asked Questions

Can I die from hip replacement surgery?

Death directly from hip replacement is extremely rare—fewer than 1 in 1,000 patients. Most deaths that occur are in patients with serious heart or lung disease, and are usually related to those conditions rather than the surgery itself. Your surgeon will assess your overall health before surgery to determine whether the risks are acceptable for you.

How long does it take to recover from hip replacement?

Most people can walk with a walker or crutches within days and transition to a cane within a few weeks. Full recovery—returning to normal activities without pain—typically takes three to six months. Some people continue to improve for up to a year. Physical therapy is essential and usually begins the day after surgery.

What should I do to reduce my risk before surgery?

Lose weight if you are overweight, control blood sugar if you have diabetes, and treat any heart or lung problems. Stop smoking at least two weeks before surgery. Take all prescribed medications unless your surgeon tells you to stop. Discuss any supplements or over-the-counter medications with your surgeon, as some can increase bleeding risk.

Is it normal to have pain after hip replacement?

Some pain and discomfort are normal in the first weeks and months after surgery. Pain should gradually decrease over time. Sharp, severe pain that suddenly worsens, or pain that does not improve with medication and rest, should be reported to your surgeon. This can signal a complication like infection or dislocation.

Can I have a second hip replacement if the first one fails?

Yes, revision surgery is possible if an implant loosens, wears out, or becomes infected. Revision surgery is more complex than the first replacement and has a longer recovery time. The success rate is good, but the implant may not last as long as the original. Discuss the possibility of revision with your surgeon before your first surgery.