Patient Education · Hip

Total Hip Replacement

The operation people are most surprised by — because of how fast it works. Here is what it is, how it goes, and what the weeks afterward really look like.

Dr. Darin W. Allred Darin W. Allred, MD Board-certified orthopedic surgery & sports medicine
1–2 hrsTypical time for the operation itself
92%Projected to still be working at 30 years
2–3 wksMost people are off the walker
6 weeksOf taking it easy while bone grows into the implant

Hip replacement has a nickname in the medical literature: the operation of the century. That is not marketing. Of everything we do in orthopedics, this is the one where people most often tell me, weeks later, that they forgot which side we operated on.

Why the hip hurts

Your hip is a ball and socket. The ball is the top of your thigh bone. The socket is a cup in your pelvis. Both surfaces are capped with smooth cartilage, and that cap is what lets the joint turn quietly under your whole body weight.

Arthritis wears that cap away. As it thins, the gap between ball and socket closes, and eventually bone grinds directly on bone. Hip arthritis has a particular set of tells, and they surprise people:

  • The pain is usually in the groin, not the outside of the hip. Pain on the outer hip is more often bursitis or tendon trouble.
  • It can show up in the knee. The nerves fool you. I have replaced hips for people who came in convinced the problem was their knee.
  • Putting on socks and shoes gets hard. Stiffness often arrives before the worst of the pain.
  • Getting out of a car or a low chair is the moment most people name.
Illustration of the worn ball being removed from the top of the thigh bone
Early in the operation the worn ball at the top of the thigh bone is removed.

What a hip replacement actually is

We take out the worn ball and resurface the socket, then rebuild the joint with parts that glide instead of grind:

  • A metal stem set down inside your thigh bone. Its surface is roughened so your own bone grows into it and locks it in place. That growing-in is why we ask for six easy weeks.
  • A new ball on top of that stem, in the size that fits you.
  • A cup pressed into the socket of your pelvis, with a smooth, hard-wearing liner inside it.
Illustration of a total hip replacement in place
A hip replacement in place: a metal stem set into the thigh bone, a new ball on top of it, and a cup lining the socket of the pelvis.

The posterior approach, and why I don't use hip precautions

I go in from behind the hip. Some surgeons go in from the front. Both work, both are good operations, and any surgeon who tells you their approach is the only right one is selling something. What matters far more than the direction is what gets repaired on the way out.

The old reputation of the posterior approach was dislocation, and the old fix was hip precautions: don't bend past 90 degrees, don't cross your legs, sleep with a pillow between your knees, sit only on raised chairs, for three months. Many patients remember a parent living that way.

I don't do that. I repair the capsule and the tissues at the back of the hip as I close, which is the part the old technique left open, and the dislocation risk drops accordingly. So there is no pillow, no raised toilet seat, no list of forbidden chairs.

There is exactly one position to avoid, and only for six weeks: pulling your knee up high toward your chest while your leg is turned inward and crossing the middle of your body. All three at once. Your therapist will show you what that feels like so you can recognize it. Otherwise, sit how you sit, sleep how you sleep, and bend to tie your shoe.

Who it is for — and who should wait

The honest test is not what your X-ray looks like. It is what your life looks like. Surgery is the right answer when:

  • Groin pain runs your day and limits how far you walk.
  • It wakes you at night, or hurts at rest.
  • Simple things have become projects — socks, shoes, the car, the stairs.
  • You have given the non-surgical tools a real try — activity changes, strength work, weight and metabolic health, anti-inflammatory medicine, sometimes an injection — without enough relief.
  • Your X-ray shows advanced arthritis to match those symptoms.

Your general health matters more than your age. What we want fixed before surgery, not because we're being difficult but because these are what drive infection: uncontrolled blood sugar, smoking, and significant obesity. Those are conversations, not disqualifications.

How the operation goes

  1. Anesthesia. Most patients have a spinal — numb from the waist down, with sedation so you are asleep — plus numbing medicine placed around the hip during surgery. That combination is why most of my patients are walking the same day and need very little narcotic.
  2. The approach. An incision over the back of the hip, and we work between the muscles to reach the joint.
  3. The worn ball comes out. The arthritic head of the thigh bone is removed.
  4. The socket is prepared and the new cup is pressed into place, with its smooth liner.
  5. The stem goes in. The thigh bone is shaped to accept the stem, and the new ball is put on top.
  6. Length and stability are checked. Before closing, I test the hip through the positions that matter and check leg length against the other side.
  7. The capsule is repaired — the step that lets you skip the precautions — and the skin is closed under a waterproof dressing you can shower with the next day.

The operation takes one to two hours. Most people go home the same day or after one night.

Recovery

Hip recovery is usually easier than knee recovery. The joint tends to feel better quickly, and the main job is to protect the bone growing into the implant while you get moving.

  • Day of surgeryUp and walking with a walker. You meet the therapist before you leave. Home the same day or the next morning.
  • First 2 weeksWalk around the house every hour you are awake — that is your blood-clot prevention as much as the aspirin. Aspirin 81 mg twice a day, and for the hip we continue that a full four weeks, longer than for a knee. Shower the day after surgery with the dressing on. Expect dramatic bruising down the thigh; it looks alarming and it is normal.
  • 2–3 weeksMost people trade the walker for a cane, then for nothing. Follow-up visit around two weeks.
  • Through 6 weeksTake it relatively easy while your bone grows into the implant. Keep avoiding that one position. Walking is the program — most of my hip patients need very little formal therapy, and I would rather you walk daily than do exercises grudgingly.
  • 6 weeks onBack to ordinary life. If it was your right hip, driving usually becomes reasonable around here, once you are off narcotics and your leg reacts normally.
  • 3 monthsMost of your improvement is in. Many people are back to hiking, travel, and work well before this.

The risks, honestly

Serious complications are uncommon, in the range of a few percent, but no operation is risk-free and I will not pretend otherwise.

  • Infection (about 1%) The one we work hardest to prevent — the skin washes, the nose treatment, blood-sugar control, and postponing when your risks are not optimized. A deep infection can mean more surgery.
  • Blood clots A clot in the leg can travel to the lungs, which can be life-threatening. Prevention is walking early and often plus a blood thinner — aspirin for four weeks for most people, a stronger one such as Eliquis, Xarelto, or Pradaxa if you have had a clot before, have a clotting disorder, or are in cancer treatment. New calf pain or new ankle swelling in the weeks after surgery is a call-the-office-today symptom.
  • Dislocation The ball can come out of the socket, almost always in the first weeks and almost always in that one position. Repairing the capsule is what makes this uncommon. If it happens, it is usually put back without another operation.
  • Leg-length difference I measure and check during surgery, but perfect symmetry is not always possible — a small difference sometimes remains, and a shoe insert handles it. A hip that is stable is worth more than a hip that measures exactly even.
  • Fracture around the implant The thigh bone can crack while the stem is seated, or years later in a fall. Uncommon, and usually fixable.
  • Nerve injury (rare) The sciatic nerve runs behind the hip. A patch of numbness near the scar is common and settles; a true nerve injury is rare.
  • Wear or loosening over the years Implants are mechanical parts. Modern ones last decades — see the numbers below — but a second operation is possible far down the road.

How long will it last?

This is the question I get most, usually from someone who has been putting the surgery off to be "old enough" for it. The old answer came from hips implanted decades ago: about 58 out of 100 still in place at 25 years. In early 2026 The Lancet published the largest study ever done on modern hips — 1.9 million of them, pooling clinical studies with national joint registries from eight countries — and the projection is about 92% still in place at 30 years.

That changes the arithmetic on waiting. The full numbers are here.

What your new hip will feel like

  • Most people forget about it. Hips tend to feel more "normal" than knees do.
  • A patch of numbness beside the scar is common and usually shrinks over a year or two.
  • Occasional clicking is normal. It is metal and plastic.
  • You may set off airport metal detectors. You do not need a card for it; just tell them.
  • Dental care: I ask you to hold off on routine dental work for three months. After that, unless you have a condition that weakens your ability to fight infection, you do not need antibiotics before dental visits — the dental and orthopedic academies changed that guidance years ago.
This page is general education. It describes how I do this operation and what most patients experience. It does not replace the conversation we will have about your own hip, your health, and your goals. If anything here does not match what you were told in clinic, ask — your own instructions always come first.