Is It Normal to Have Lower Back Pain After Hip Replacement?

Medically reviewed by Dr. Rob Letizia, PT, DPT · Doctor of Physical Therapy, 25+ years treating spine & orthopedic conditions · Last reviewed 2026-09-21

The hip is fixed. The groin pain that sent you to the surgeon in the first place is gone. And now your lower back hurts — sometimes worse than the hip ever did.

This is one of the most common questions we field from post-surgical patients at our Wayne, NJ clinic, and it is almost never the question people expect to be asking. It also tends to arrive at the worst possible moment: a few weeks in, when everything else is finally going right.

Here is what is usually happening, how to tell hip-driven back pain from a spine problem, and what actually changes it.

Is it normal to have lower back pain after hip replacement?

Yes — it is common, and in most cases it is a mechanical problem rather than a sign that something went wrong with the implant.

The reason is that a hip replacement changes how you walk, and your lower back is downstream of how you walk. An arthritic hip spends years being protected. The pelvis sits tilted. The muscles on the side of the hip get weak. The front of the hip shortens so the leg stops travelling fully behind you. Then the joint gets replaced — and none of those adaptations get replaced with it.

Your lumbar spine has been quietly covering for that hip for years. When you start walking more, on a joint that now moves differently, the spine is the part that notices first.

That said, "common" is not the same as "ignore it." Some patterns need a phone call the same day, and those are listed further down.

Lower Back Pain After Hip Replacement: What Each Pattern Usually Means

The 3-Signal Hip-or-Spine Rule

The single most useful thing you can work out at home is whether the back pain is coming from how the new hip is moving or from the spine itself, because the two need opposite work. Three signals point at the hip:

1. It tracks your walking. Worse the longer you are up, better after a night's rest, worse on the days you did more.
2. It started after the operation, not before, and it is worst on the operated side.
3. It changes when someone corrects how you walk — often noticeably within a single session, before any strength has been built.

Point the other way and the answer flips. Pain that does not track your walking, that is there lying down, or that is recognisably the same pain you had before the hip was replaced, is a spine question and should be assessed as one. Working harder on hip strengthening will not resolve a lumbar problem, and it delays the assessment that would.

Why a new hip makes the lower back hurt: the four mechanisms

1. The pelvis drops on every step

The muscles on the side of the hip keep your pelvis level when you stand on one leg — which is what walking is. They are weak before surgery, weaker after it, and they are the single biggest reason a hip that feels fine at rest still limps. When the pelvis drops slightly on each step, the lumbar spine has to correct it, several thousand times a day.

2. The hip will not fully extend, so the back does it instead

An arthritic hip spends years quietly avoiding the last part of straightening, and the muscles at the front shorten to match. Then the joint gets replaced and the tightness stays, because the tightness was never in the joint. A hip that will not fully extend cannot push off properly — and the motion has to come from somewhere. It comes from the lower back.

3. The pelvis is unwinding from years of tilt

Long before the operation, the pelvis was already sitting tilted to accommodate a joint that hurt. That tilt does not reset the day the implant goes in. As it rebalances over weeks to months, the tissue on one side is being asked to lengthen and the other to shorten, and one-sided low back ache is a normal part of that process. It is also the usual explanation behind the feeling that the operated leg is longer.

4. You are walking more than you have in years

This is the one nobody warns people about. The operation works: the joint stops hurting, and activity goes up sharply. A lumbar spine that was never tested because you were not walking far is now being tested daily. That is not the hip going wrong — but it is a real problem, and it needs its own answer.

Week by week: when lower back pain after hip replacement usually shows up

Weeks 1–2

Back pain here is usually about position rather than gait. You are sitting more, often propped in a chair, and moving on a walker with short, careful steps. Swelling in the thigh and down the leg is normal in the first weeks and is largely gravity doing what gravity does. The useful move in this window is to stop losing ground on hip extension: lie flat rather than staying propped all day, and do the front-of-hip work your therapist gave you, staying inside whatever restrictions your surgeon set.

Weeks 2–6

This is when the abductor pattern usually announces itself. Walking distance is climbing, the walking aid is coming out, and each step is being made with a pelvis that is not yet being held level. The ache is typically across the low back and into the buttock, builds over the day, and settles overnight. Frequency beats distance in this window, and breaking up long sitting every hour while awake helps both the back and the swelling.

Weeks 6–12

By six weeks, swelling should be settling and you should be walking further without a device — both trending the right way. Most precaution periods end around here, though you should confirm that with your surgeon rather than assuming, in either direction. Back pain that appears or worsens in this window is usually the extension problem: you are walking faster and further, and the stride is being bought from the lumbar spine.

At 3 months — the checkpoint that matters

At three months, the question is whether the limp is gone. If pain has settled but you are still limping, that is hip-abductor weakness, and it does not resolve by waiting. It is the single most common thing we are asked to fix late, and it is very fixable. If the limp is still there, the back pain riding on top of it is very unlikely to settle either — they are the same problem.

Months 3–6 and beyond

If the limp has gone and the back pain went with it, that was gait, and it is finished. If the limp has gone and the back pain stayed, the spine now deserves its own assessment rather than more hip work. Separately, a leg-length sensation that has not settled by six months should be measured properly rather than tolerated, and groin pain still present at six months needs a diagnosis.

The 12-Week Level-Pelvis Protocol

This is the sequence we run for hip-driven lower back pain, and it is built around the three-month limp checkpoint rather than around a number of visits. Everything in it stays inside the restrictions your own surgeon set.

1. Weeks 1–2 — stop losing extension. Lie flat rather than propped in a chair all day. Do the specific front-of-hip work your therapist gives you, gently and often. The point is to stop losing ground, not to stretch aggressively into a fresh surgical site.
2. Weeks 2–6 — short walks, often. Frequency beats distance in the early weeks, and breaking up long sitting every hour while awake is part of the programme, not an optional extra.
3. Weeks 2–12 — direct abductor work. The muscles on the side of the hip need deliberate, targeted loading. They do not get strong as a side effect of walking, and walking more with a dropping pelvis simply rehearses the pattern.
4. Weeks 6–12 — have someone watch you walk. You have been walking a certain way for years to protect an arthritic joint; that pattern is a habit now, and habits outlive the reason for them. Gait does not correct itself through repetition of the wrong version.
5. At 12 weeks — read the result. Limp gone and back pain gone: finished. Limp gone and back pain remaining: refer the spine for its own assessment. Limp still present: the abductor work has not been enough or has not been specific enough, and that is what to escalate.

Note the design of step 5. The protocol is written so that it tells you when it has not worked, and what that means, rather than simply continuing.

Will lower back pain after hip replacement go away?

When the cause is gait — abductor weakness, lost hip extension, a pelvis unwinding from years of tilt — it resolves when the gait resolves, and the three-month limp checkpoint is the honest place to judge that. It does not resolve by waiting, and it does not resolve by walking more, because walking more rehearses the pattern that is causing it.

When the cause is a lumbar problem that predates the hip, the hip surgery did not create it and hip rehabilitation will not settle it. That is not a failure of the operation. It is a second thing, and it needs to be treated as one.

The reason the honest answer is "it depends which one you have" is that both are common, both turn up in the same weeks, and they feel similar to the person having them. Sorting them is the whole value of an in-person assessment.

Red flags: when lower back pain after hip replacement needs a call, not a programme

Most post-hip back pain is mechanical. These are the exceptions, and they are not things to sit on:

• Sudden severe pain with inability to bear weight, especially if the leg looks shorter or turned in or out — possible dislocation. This is an emergency; go to the emergency department and do not try to walk it off.
• Calf pain or tenderness, sudden swelling clearly worse in one leg, skin that feels hot, or red or purplish discolouration — possible blood clot. With shortness of breath or chest pain, call emergency services.
• Fever or shivering, or a wound that is increasingly red, hot or swollen, leaking fluid or pus — possible infection, same-day call.
• New pain after a period of doing well, particularly following a dental or other procedure — late infections happen and are easy to dismiss.
• A fall onto the new hip, even if you feel able to walk afterwards.
• Numbness across the groin, inner thighs or the area you sit on, or any new change in bladder or bowel control. Together with back pain this can mean cauda equina syndrome, where the nerves at the base of the spine are compressed. It is rare, it is a surgical emergency, and delay causes permanent damage. Do not wait to see if it settles overnight.
• Weakness in both legs, or weakness that is getting worse — a foot that catches, slaps or drags.
• Pain that does not change with position, or that reliably wakes you from sleep. Mechanical back pain has good positions and bad ones.

The general pattern worth remembering is that what matters is a change, rather than a level. Pain that is steadily improving with ordinary bad days is normal. Pain that escalates week over week is not.

Started with an AI assistant? Bring the plan in.

Recovery after a hip replacement runs for months, and most of it happens between appointments. That is why people end up asking ChatGPT, Gemini or Claude whether back pain after a hip replacement is normal, whether they should stop walking, and whether one leg really is longer. The general information is usually reasonable.

What an assistant cannot do is watch you walk, test your hip abductors, measure a leg-length difference, or tell you whether the ache across your back is the pelvis dropping or a lumbar spine that was already unhappy before the operation. It also cannot tell you that the precaution advice it just gave you was written for the other surgical approach.

Bring your precaution list and whatever you have been doing. We will tell you which parts still apply, what to add, and what needs your surgeon instead of us.

Book a Plan Check — one visit, in person at our Wayne, NJ clinic. We test the plan you are already following, tell you which parts to keep, and correct what is provoking it · call or text (973) 689-7123. Reviewed by Dr. Rob Letizia, PT, DPT — 11 years leading Spectrum Therapeutics, 25 years in practice, 300+ five-star patient reviews.

Frequently asked questions about lower back pain after hip replacement

Is it normal to have lower back pain after hip replacement?

Yes, it is common, and it is usually mechanical rather than a problem with the implant. A hip replacement changes how you walk, and the lower back is downstream of how you walk. The usual drivers are hip abductor weakness letting the pelvis drop on each step, loss of hip extension so the lumbar spine supplies the missing stride, and a pelvis unwinding from years of tilt. It still needs checking against the red-flag list.

Will lower back pain go away after hip replacement?

If the cause is gait, it resolves when the gait resolves, and three months is the point at which to judge it. If the cause is a lumbar problem that predates the hip, hip rehabilitation will not settle it and the spine needs its own assessment. Both are common, and they present in the same weeks.

Why does my lower back hurt more after hip replacement than it did before?

Usually because you are walking far more than you were. The operation works, activity goes up sharply, and a lumbar spine that was rarely tested is now being tested every day — on a gait pattern that has not caught up with the new joint yet.

How long does lower back pain last after hip replacement?

There is no single number, and anyone giving you one is describing someone else's recovery. The useful checkpoints are the ones the recovery itself runs on: at six weeks, swelling settling and walking further without a device; at three months, is the limp gone; at six months, a leg-length sensation or groin pain that has not settled needs measuring and diagnosing rather than tolerating. Back pain that is riding on a limp will generally track the limp.

Why does my operated leg feel longer, and can that cause back pain?

Very common, and usually not what it feels like. Most of the time the leg lengths are within a few millimetres, and what you are feeling is a pelvis that has been sitting tilted for years while the arthritic hip wore down, plus tight tissue on one side. It typically settles over weeks to a few months as the muscles rebalance, and the one-sided back ache that comes with it settles alongside. If it persists past six months, it is worth measuring properly rather than guessing.

Should I stop walking if my back hurts after a hip replacement?

Soreness after activity that settles by the next morning is the normal cost of progress. But more walking is not the treatment here — walking more on a pelvis that is dropping simply rehearses the pattern. Short, frequent walks plus direct abductor work and someone actually watching your gait is what changes it. Pain that escalates week over week is a different conversation and belongs with your surgical team.

Can physical therapy fix back pain caused by a hip replacement?

When it is gait-driven, that is exactly what physical therapy is for: targeted hip abductor strengthening, deliberate work on hip extension, and gait correction by someone watching you walk. A limp at three months is a training problem, not a surgical one — but it will not resolve on its own.

Do I need a referral to start physical therapy for this in New Jersey?

New Jersey has direct access, so you can generally start physical therapy without a physician's referral. There is one firm exception to know about: any Medicare plan — including every Medicare Advantage plan and AARP Medigap — requires a doctor's script. If you have just had a hip replaced you are almost certainly already under a surgeon, so this is usually a phone call rather than an obstacle.

Getting it sorted in Wayne and Northern New Jersey

Lower back pain after a hip replacement is one of the most fixable problems in post-surgical rehabilitation — provided someone works out which of the two things it is. That is a twenty-minute question in person and an unanswerable one over the internet.

At Spectrum Therapeutics of NJ in Wayne, we treat post-surgical hip patients from across Passaic County and Northern New Jersey, including people who finished their formal therapy months ago and were told the limp would settle by itself. Our Doctors of Physical Therapy will watch you walk, test the abductors, check hip extension, and tell you plainly whether this is a hip problem wearing a back-pain disguise or a spine that needs its own plan.

If your back has started hurting since your hip was replaced, call us at 973-689-7123 to schedule an evaluation.

Related Services at Spectrum Therapeutics

• Read the full hip replacement recovery timeline
• See our hip rehabilitation services
• Explore our lower back and spine treatment
• Post-surgical rehabilitation in Wayne, NJ

Questions? Call (973) 689-7123 or schedule your appointment online.