Anterior and posterior hip replacement put in the same kind of new joint. The difference is the route in: anterior goes through the FRONT of the hip, posterior through the back.
Anterior can make the first few weeks slightly easier, with a little less pain in the first days and faster early progress in some studies. By about three to six months the two are level, and the long-term results don’t differ.
What matters more is your surgeon.
A surgeon who does a lot of hip replacements through one approach will usually get better results than a surgeon using an approach they do less often.
What’s actually different
- Anterior (from the front): the cut is on the front of the hip. The surgeon works in the gap between muscles instead of detaching them, often on a special operating table with X-ray guidance
- Posterior (from the back): the cut is at the back and side of the hip. Some small muscles at the back of the joint are detached to reach it, then usually repaired. It’s the long-established, widely used route
- Lateral (from the side): some surgeons use a third route. Long-term results are similar
- The implant is the same idea. A ball and socket replaces the worn joint whichever way the surgeon goes in. Younger, active people may also hear about hip resurfacing
Early recovery: what the evidence says
- First days: on average, a little less pain after anterior surgery. The difference is small
- Weeks 2 to 6: some trials show a modest head start in walking and hip function after anterior
- By 3 to 6 months: no meaningful difference. At one year, none
- Operation time: posterior surgery tends to be quicker, by around 15 minutes
- Movement rules: posterior surgery more often comes with hip precautions for the first weeks. Anterior often has fewer rules. See hip replacement precautions
Both approaches still need the same work afterward: walking little and often, and strengthening the side of the hip. See hip replacement recovery week by week.
Choose the surgeon first. The approach comes with them.
Dislocation
- It’s uncommon with both approaches, around 1 to 2 in 100 or fewer
- Posterior used to carry a higher risk. Modern repair of the tissues at the back of the hip has narrowed the gap
- Some studies find a slightly lower rate after anterior, but the difference is small and not consistent between studies
- Other things matter more: how well the parts are positioned, the size of the ball, and your own risk factors, such as previous surgery on that hip or conditions that affect muscle control
Numbness on the thigh
- Common after anterior surgery. A skin nerve that supplies feeling to the outer front of the thigh runs close to the incision. When studies look for it carefully, around 1 in 3 people notice a numb or tingly patch
- It affects feeling only. It doesn’t weaken the leg or change how you walk, and studies find no difference in function
- It usually fades. Most people improve within a year or two. Some are left with a smaller patch that doesn’t bother them
Other trade-offs
- Wound healing in larger bodies: the anterior incision sits near the groin crease. In people carrying a lot of weight, wound problems are several times more likely with anterior surgery, so many surgeons choose another route
- The learning curve is real: a large national registry found surgeons new to the anterior approach had a higher chance of their patients needing a redo operation over their first 100 or so cases. After that, results matched experienced surgeons
- Your hip matters: previous surgery, hip shape, bone quality and body build can make one route a better fit
- Both are demanding operations. AAOS OrthoInfo notes that both traditional and less invasive hip replacement go better with an experienced surgeon and team
Questions to ask your surgeon
- Which approach do you use most, and roughly how many hip replacements do you do each year?
- Why is this approach right for my hip and my body?
- Will I have movement rules after surgery, and for how long?
- Should I expect any numbness or wound issues?
For more to raise at your appointment, see questions to ask before orthopedic surgery. Still deciding whether you need surgery at all? See when is it time for a hip replacement.
Go to the emergency department if
- After surgery, the hip suddenly clunks or gives way and you can’t put weight on the leg
- The operated leg looks shorter than the other, or turned in or out
- You have chest pain or sudden shortness of breath
Call your surgeon today if
- The wound is red, hot, spreading or leaking, or you have a fever
- Your calf is painful, swollen or warm
- Pain is getting WORSE instead of slowly better
Mention it at your next review if
- A numb patch on the thigh turns into burning pain, or keeps growing
- You still limp after about three months
- You’re unsure which approach you had or which rules apply to you
Anterior or posterior, the best approach is the one your surgeon does often and does well.