Hip Replacement Risks: What Can Go Wrong and the Red Flags to Watch For

Key Takeaways

• Most hip replacements go well, though infection, dislocation, blood clots and implant loosening remain possible.
• Risks follow a timeline, with infection, clots and dislocation clustering early, and wear, loosening and revision appearing years later.
• Fever with a leaking wound, sudden calf pain, breathlessness or an inability to stand all need same-day medical attention.
• Your weight, smoking status, other health conditions and strength before surgery shape your personal risk more than most people realise.

Waiting for a hip replacement usually comes with a quiet list of worries, and most of them circle the same question: what happens if it does not go to plan? That question deserves a direct answer, because these risks are well studied, mostly uncommon and reasonably predictable in their timing.

Knowing what can go wrong is practical. You learn which sensations belong to ordinary healing, which ones justify a phone call and which ones need a hospital that day. It also sharpens the conversation with your specialist, because the hip replacement options available to you each carry a slightly different risk profile.

Individual risk varies. Age, weight, other health conditions, previous hip operations and your strength going into surgery all shift the picture, so two people having the same procedure can have very different experiences. Knowing where you sit turns a nervous wait into an informed one.

Why Hip Replacement Risks Are Worth Understanding Early

Reading about complications before surgery tends to settle people more than it worries them. You stop treating every ache as a warning sign, and you stop brushing aside the changes that genuinely matter. Three things shape how you read your own recovery:

The Difference Between Ordinary Healing and a Complication

Bruising that tracks down the thigh, swelling around the hip and knee, warmth over the wound and disturbed sleep are all part of ordinary recovery. They usually peak in the first fortnight and ease steadily after that.

A complication tends to break that pattern. Pain that climbs after a period of improvement, swelling that returns without an obvious cause, or a wound that starts leaking after it has dried are all changes in direction, and direction is what your team listens for.

The Timing Pattern of Most Problems

Infection, blood clots and dislocation cluster in the early weeks, when tissues are healing and the joint is at its least stable. Loosening, wear and fracture around the implant tend to appear much later, sometimes after a decade or more of good function. Knowing which window you are in helps you judge how urgently a new symptom needs attention.

The Weight of Your Own Health History

Diabetes, a higher body weight, smoking, inflammatory arthritis, previous hip surgery and medicines that suppress the immune system all nudge risk upward. None of them rules out surgery. They usually mean your team spends more time on preparation, and it is one reason the consent conversation is personal, not a standard script.

What Can Go Wrong During Surgery

Complications in theatre are uncommon and most are managed on the spot by the surgical and anaesthetic teams. A few still shape how your early recovery is handled:

Bleeding and Transfusion

Hip replacement involves cutting through muscle and bone, so some blood loss is expected. Most people never need a transfusion. Blood-thinning medicines, certain supplements and some bleeding conditions raise the chance, so your team will ask for a full list of everything you take, including fish oil and herbal products.

Fracture of the Femur or Socket

Preparing the thigh bone and socket to accept the implant places stress on bone. Bone weakened by osteoporosis can split during that process. Small cracks may be secured with wires or cables during the same operation. A larger fracture can change the implant chosen and slow how quickly you are allowed to put weight through the leg.

Nerve Injury Around the Hip

Nerves running near the hip can be stretched or bruised and, very rarely, cut. The sciatic and femoral nerves are the ones usually discussed, and the result can be numbness, pins and needles, or weakness in the leg or foot. Most of these settle over weeks to months. Long-standing hip dysplasia, revision procedures and lengthening of the leg during surgery all raise the risk.

Blood Vessel Injury

Damage to the vessels sitting close to the joint is rare and is repaired during the operation when it does occur. It is one reason hip replacement is done in a hospital with vascular support on hand.

Anaesthetic and Cardiac Events

Any major operation carries a small risk of heart, lung and kidney complications, particularly for older adults and people with existing cardiac or respiratory disease. Anaesthetists screen for this before the day, and options such as spinal anaesthesia may be offered depending on your circumstances.

Complications in the First Six Weeks

Most complications show themselves in the early weeks, and this is the period where quick reporting makes the biggest difference:

Wound and Deep Joint Infection

A superficial wound infection may respond to antibiotics alone. Infection that reaches the implant is far more serious and usually needs a washout in theatre, and sometimes an exchange of parts. Diabetes, a higher body weight, smoking and skin conditions near the hip all raise the risk.

Deep Vein Thrombosis and Pulmonary Embolism

Reduced movement after surgery makes clots more likely. A deep vein thrombosis (DVT) forms in the leg and causes calf pain, tightness, warmth or one-sided swelling. A pulmonary embolism (PE) happens when part of that clot travels to the lung, causing breathlessness, chest pain or a cough that brings up blood.

Early walking, compression stockings, calf pumping exercises and prescribed blood-thinning medicine all lower the risk.

Dislocation of the New Joint

The ball can come out of the socket, most often in the first three months while soft tissues are still tightening. Deep bending, crossing the legs and twisting on a planted foot are common triggers, though the specific precautions depend on the surgical approach used.

A dislocation causes sudden severe pain and leaves you unable to stand on the leg. Most are put back into place under sedation without further surgery, though repeated dislocation may lead to revision.

Persistent Swelling and Stiffness

Swelling around the hip, thigh and ankle is normal for several weeks and often worsens late in the day. Elevation, ice, walking little and often, and prescribed exercise usually keep it moving in the right direction. Swelling that suddenly increases or concentrates in the calf needs a check.

Pain That Does Not Settle

Discomfort should trend downwards across the first six weeks, with occasional flare-ups after busier days. Pain that intensifies, wakes you consistently, or is not touched by prescribed medicine is worth reporting. Groin pain, thigh pain and buttock pain each point in different directions, so describing exactly where it sits helps your team narrow the cause.

When the Hip Works but Something Still Feels Off

Some outcomes are not complications in the strict sense, though they can still be disappointing. Naming them early tends to reduce the frustration, because most respond well to targeted rehabilitation:

Leg Length Difference

A small difference in leg length is common after hip replacement and often settles as swelling reduces and the pelvis rebalances. Larger differences may be managed with a shoe raise. Surgeons work to restore stability and joint mechanics, and a marginally longer leg is occasionally the trade-off for a hip that stays in place.

Persistent Limp and Muscle Weakness

Years of limping before surgery leave the gluteal muscles deconditioned, and a new joint does not reverse that on its own. Weakness in the hip abductors is a frequent reason people still limp months later. Progressive loading under supervision is usually what shifts it.

Clicking and Clunking Noises

Occasional noise from an artificial joint is common and usually harmless, particularly with ceramic or other hard bearing surfaces. Noise paired with pain, instability or a feeling that the hip might give way is worth reviewing.

Numb Patches Near the Scar

Small skin nerves are cut when the incision is made, leaving an area of numbness around the wound. That patch often shrinks over the first year. It rarely affects function, though it can feel strange when clothing brushes against it.

Problems That Can Appear Months or Years Later

Modern implants are durable and most people never face these issues. They matter more for younger, heavier and more active patients, whose joints accumulate more loading cycles over time:

Aseptic Loosening

The bond between implant and bone can weaken over many years, causing groin or thigh pain that worsens with weight bearing. It is picked up by comparing X-rays taken over time, and it remains one of the more common reasons for revision surgery.

Wear of the Bearing Surfaces

Every step wears the bearing surfaces slightly. Wear particles can trigger a reaction in surrounding bone, known as osteolysis, which loosens the implant. Highly cross-linked polyethylene and ceramic bearings have reduced this considerably compared with older designs.

Periprosthetic Fracture

A fall or a significant knock can fracture bone around the implant, particularly in people with thinning bones. Treatment ranges from fixation with plates and cables through to replacing the implant. Bone health, balance training and home safety all matter here.

Late-Onset Infection

Bacteria travelling through the bloodstream from a dental abscess, skin infection or urinary infection can settle on an implant years after surgery. Treating infections promptly and telling your dentist about your joint replacement are habits worth keeping for life.

Revision Surgery

Revision replaces some or all of the implant. It is a longer, more complex operation with a slower recovery than the first one. The Australian Orthopaedic Association National Joint Replacement Registry tracks how these implants perform, and its reporting on procedures to the end of 2024 puts 10-year revision rates for modern hip combinations between 2.5% and 8.0%. That range reflects differences in the device used, your age and your general health. The younger you are at your first replacement, the more likely a revision becomes at some point.

These figures are a general guide drawn from national registry reporting. They describe large groups of people, not your individual result.

Red Flags That Deserve a Same-Day Response

Most post-operative worries turn out to be ordinary healing. A small number do not, and these are the ones your team wants to hear about straight away, at any hour:

Signs of Possible Infection

A temperature above 38°C, shaking chills, redness spreading out from the wound, fluid or pus leaking after the first few days and pain that climbs after easing all point towards infection. Feeling generally unwell alongside any of these adds weight to the concern.

Signs of Possible Blood Clots

New calf pain, tightness or tenderness, or swelling that affects the operated leg more than it did the day before, may indicate a DVT. Sudden breathlessness, sharp chest pain, a racing heart or coughing up blood may indicate a PE. That second group is a medical emergency.

Signs of Mechanical Problems

Sudden severe hip pain with an inability to stand, a leg that looks shorter or rotated, or a loud clunk followed by instability all suggest dislocation or a fracture. This usually follows a twist, a fall or a deep bend. Avoid trying to walk it off.

Steps for Getting Help Quickly

Having a simple plan removes hesitation when something feels wrong:

• Phone your surgeon’s rooms first for wound, pain or movement concerns during business hours.
• Contact your general practitioner (GP) for after-hours advice on wounds, medicines and general recovery questions.
• Attend an emergency department for sudden severe pain, an inability to stand, or a suspected dislocation.
• Call triple zero (000) for breathlessness, chest pain or coughing up blood.
• Keep your operation details, implant information and medicine list somewhere easy to reach.

The steps above are a general guide only. Your surgical team may give you different instructions based on your operation, your health and where your surgery was performed.

What Raises or Lowers Your Personal Risk

Risk is not fixed. Several factors sit within your influence in the weeks before surgery, and small improvements across a few of them tend to add up:

Existing Health Conditions

Diabetes with higher blood glucose levels, heart and lung disease, kidney disease, inflammatory arthritis and immune-suppressing medicines all raise the chance of infection and slower healing. Bringing these conditions under better control before surgery is usually worth the short delay it sometimes creates.

Body Weight and Nutrition

A higher body weight can increase surgical complexity, wound complications and load through the implant. Protein intake, iron levels and vitamin D also influence wound healing and strength. Sustainable changes made over months tend to be more useful than dramatic ones attempted close to the surgery date.

Smoking and Alcohol

Smoking narrows small blood vessels and slows both wound and bone healing, and it is associated with higher infection and revision rates. Stopping several weeks beforehand can measurably improve outcomes. Heavy alcohol use affects healing, bone quality and anaesthetic safety.

Previous Hip Surgery

Scar tissue, altered anatomy and retained metalwork from earlier procedures make surgery more complex and raise the risk of nerve injury, fracture and dislocation. Your surgeon may plan additional imaging and choose different implants in these situations.

Strength Going Into Surgery

People who enter surgery stronger tend to move earlier, need less assistance and reach their milestones sooner. Hip abductor and quadriceps strength are particularly relevant. A structured prehabilitation program can build both without aggravating an arthritic joint.

Lowering Your Risk Before and After Surgery

Much of what protects a new hip happens outside the operating theatre. Preparation and rehabilitation do a lot of the work:

Preparing Your Body in the Weeks Beforehand

Strength work, walking within comfort, dental checks, blood glucose control and stopping smoking all belong in this window. Skin over the hip and leg should be intact and free of cuts, rashes or infections on the day of surgery, since broken skin is a direct route for bacteria.

Organising Your Home and Support

Loose rugs, trailing cords and low chairs cause falls at exactly the wrong moment. Preparing your home with a higher chair, a handrail where one is needed, and someone to help for the first week or two removes a lot of avoidable risk before you are tired and unsteady.

Following Movement Guidance Early

Precautions differ between anterior and posterior approaches, so the instructions you are given matter more than general advice found online. Early walking protects against clots and stiffness, though pushing distance in the first week often backfires.

Rebuilding Strength With Structured Rehabilitation

Walking alone does not restore hip abductor strength. Progressive loading, guided by a physiotherapist or exercise physiologist, is what closes the gap between a hip that works and a hip that feels like yours again.

Attending Every Follow-Up Review

Scheduled reviews and X-rays can pick up loosening and wear long before symptoms appear. Skipping them removes the chance to act while a problem is still small and straightforward to manage.

Recognising What Is Normal and What Is Not

The worry underneath most of these questions is not really about numbers. It is about handing over control of your own body for a while and not knowing whether what you feel afterwards is normal.

That worry loses most of its grip once the unknowns have names. Alert without being anxious is a good place to walk into theatre from, and that is where most people end up once they can tell healing and trouble apart.

Many people who have a hip replacement report easier walking, better sleep and a return to the things that had quietly dropped off their week. To talk through your hip, your risk profile and what preparation could look like for you, book a consultation with the MTP Health team, or speak with your GP about a referral to a specialist.

Frequently Asked Questions (FAQs)

1. What is the most common complication after a hip replacement?

Ongoing pain, stiffness and a sense of leg length difference are reported most frequently overall, and these often improve with rehabilitation across the first several months. Infection, dislocation and blood clots are discussed more prominently before surgery because they need prompt treatment, even though they occur less often.

2. How long does the risk of dislocation last?

The risk is highest in the first three months, while the soft tissues around the joint heal and tighten. It reduces substantially after that, though it never disappears entirely. Certain movements carry more risk depending on the surgical approach used, so your surgeon will tell you which positions apply to your hip.

3. Can a hip replacement fail without causing pain?

Yes, in some cases. Early loosening and wear may produce no symptoms at all, which is why follow-up X-rays continue for years after surgery. Picking up a problem before it becomes painful often means a simpler operation if a revision is eventually needed.

4. Is one leg always longer after hip replacement surgery?

No. Many people notice a difference in the first weeks, and much of that comes from swelling, muscle tightness and a pelvis that has been tilted for years. Genuine differences are usually small, and where they persist they are often managed with a shoe raise.

5. Does being younger increase my hip replacement risks?

Younger patients generally recover well from the operation itself, though they are more likely to need revision surgery during their lifetime because the implant is loaded harder and for longer. This is one reason joint-preserving options are considered carefully in younger adults before a replacement is chosen.

6. Can physiotherapy reduce my risk of complications?

It can help with several of them. Guided exercise supports circulation, which matters for clot prevention, and it rebuilds the hip and thigh strength that reduces falls, limping and prolonged weakness. At MTP Health, physiotherapy and exercise physiology sit alongside orthopaedic care, so preparation and recovery can be planned together.

7. When should I go to an emergency department instead of calling my surgeon?

Go straight to an emergency department for sudden severe hip pain with an inability to stand, a suspected dislocation, or signs of serious infection such as a high fever alongside a leaking wound. Call triple zero (000) if you develop breathlessness, chest pain or cough up blood, since these may indicate a clot in the lung.

Disclaimer: This article offers general information only and does not take your personal circumstances, medical history or diagnosis into account. It is not a substitute for individual medical advice. Speak with a qualified health professional, such as your GP, orthopaedic surgeon or physiotherapist, before making decisions about hip surgery or your recovery.