Stiffness After Knee Replacement: Dr. Mayur Rabhadiya Explains Treatment

Is Stiffness Normal After Knee Replacement?

Some stiffness is expected during the early recovery period after knee replacement.

The knee may feel:

Tight
Heavy
Difficult to bend
Difficult to straighten
Stiff after sitting
More restricted when swollen
Less flexible in the morning or after activity

Early stiffness may result from:

Postoperative swelling
Pain
Muscle weakness
Guarding during movement
Bruising
Reduced confidence
Limited movement before surgery

The important issue is whether movement is gradually improving.

Persistent or worsening stiffness should be assessed rather than managed only by repeatedly increasing exercise intensity.

Dr. Mayur Rabhadiya is an Orthopedic & Joint Replacement Surgeon in Mumbai with a focused practice in total, partial, robotic-assisted and revision knee replacement.

For the general recovery pathway, read Knee Replacement Recovery Timeline.

What Does a Stiff Knee Replacement Mean?

A stiff knee replacement may involve difficulty:

Fully straightening the knee
Bending the knee sufficiently
Getting up from a chair
Using stairs
Entering a vehicle
Walking normally
Sleeping comfortably
Performing routine daily activities

Stiffness may affect:

Knee Extension

The knee cannot fully straighten.

This may contribute to:

Limping
Increased walking effort
Quadriceps fatigue
Poor standing balance
Hip or back discomfort

Knee Flexion

The knee cannot bend sufficiently.

This may make it difficult to:

Sit comfortably
Rise from a chair
Use stairs
Enter a car
Dress
Perform household activities

Both straightening and bending are important for useful function.

How Much Knee Movement Is Required?

There is no single movement target that applies to every patient.

The amount of movement needed depends on:

Daily activities
Chair and toilet height
Stair requirements
Vehicle use
Body proportions
Hip mobility
Movement before surgery

A patient may perform many routine activities without achieving extremely deep bending.

Knee replacement cannot guarantee:

Deep squatting
Cross-legged sitting
Comfortable kneeling
A particular bending angle
Movement identical to a natural knee

Functional improvement is more important than comparing one numerical measurement with another patient.

Common Causes of Stiffness

Pain and Swelling

Pain and swelling may prevent the patient from moving the knee adequately.

Swelling can:

Restrict bending
Inhibit the quadriceps
Increase tightness
Make exercise difficult
Alter walking

Read Swelling After Knee Replacement Surgery.

Limited Movement Before Surgery

A knee that was severely stiff before replacement may remain more difficult to mobilise afterward.

Long-standing arthritis may cause:

Contracted ligaments
Shortened soft tissues
Muscle weakness
Fixed bending deformity
Reduced kneecap movement

Surgery may improve movement, but it cannot always restore completely normal flexibility.

Inadequate Pain Control

When pain is poorly controlled, the patient may avoid:

Bending
Straightening
Walking
Strengthening

The pain plan should permit rehabilitation while remaining medically safe.

Arthrofibrosis

Arthrofibrosis refers to excessive scar-tissue formation inside and around the knee.

The scar tissue may bind structures that normally move separately and cause:

Painful stiffness
Progressive loss of movement
A firm endpoint during bending
Difficulty maintaining movement gained during physiotherapy

Arthrofibrosis is diagnosed after other causes of stiffness are considered.

Infection

Infection may cause:

Pain
Swelling
Increasing stiffness
Warmth
Redness
Wound drainage
Fever or chills

Some low-grade infections may present mainly as persistent pain and stiffness without obvious fever.

Implant Position or Size

In uncommon cases, implant position, rotation, size or joint balance may mechanically restrict movement.

Manipulation alone will not correct a significant implant-position problem.

Instability

A knee that feels loose may become painful and guarded, causing the patient to restrict movement.

Previous Surgery

Previous arthroscopy, fracture surgery, ligament reconstruction or earlier replacement may increase:

Scar tissue
Surgical complexity
Soft-tissue tightness
Risk of delayed movement

Early Management of Knee Stiffness

Early treatment usually focuses on:

Swelling control
Appropriate pain management
Knee-straightening exercises
Progressive bending
Quadriceps activation
Walking
Correct exercise technique
Regular physiotherapy review

A patient should not remain completely inactive because the knee is painful.

However, severe force should not be used merely to reach a numerical target.

Physiotherapy for a Stiff Knee Replacement

Physiotherapy may include:

Heel slides
Sitting knee bends
Knee-extension exercises
Quadriceps sets
Straight-leg raises when appropriate
Patellar-mobility exercises when advised
Walking retraining
Chair-rise practice
Stationary cycling when sufficient movement is present
Progressive strengthening

The programme should address:

Pain and swelling
Knee straightening
Knee bending
Quadriceps strength
Walking pattern
Functional activity

Read Physiotherapy After Knee Replacement Surgery.

Should a Stiff Knee Be Forced?

Forceful treatment can sometimes worsen:

Pain
Swelling
Muscle guarding
Fear of movement
Sleep disturbance
Exercise tolerance

Some discomfort during stretching is expected.

The programme should be reviewed when exercise causes:

Severe pain
Marked swelling lasting into the next day
Loss of previously gained movement
Inability to walk afterward
Wound stress
Significant bruising
Progressive deterioration

Consistent, controlled rehabilitation is generally preferable to occasional extremely aggressive sessions.

Why Knee Straightening Deserves Attention

Patients often concentrate only on knee bending.

However, failure to restore extension can significantly affect:

Heel contact
Walking efficiency
Standing
Quadriceps function
Balance

The patient may be advised to support the heel and allow the knee to straighten.

A pillow should not be kept permanently under the bent knee unless specifically instructed.

Exercise technique should be checked because supporting the wrong area may reinforce a flexed position.

When Should Slow Progress Be Reviewed?

Orthopedic review is appropriate when:

Knee movement is not gradually improving
Previously gained movement is being lost
The knee remains severely painful
Swelling is increasing
The wound is red or draining
The knee repeatedly gives way
The patient cannot progress walking
Physiotherapy repeatedly causes major setbacks
There is a hard or mechanical block to movement
Recovery is substantially different from the expected course

Review should not be delayed solely because the patient has been told to exercise harder.

How Is Persistent Stiffness Evaluated?

Assessment may include:

Movement before the original operation
Timing of stiffness
Pain severity
Swelling
Wound-healing history
Physiotherapy progress
Previous operations
Walking pattern
Knee bending and straightening
Ligament stability
Kneecap movement
Weight-bearing X-rays

Additional investigations may include:

Blood tests when infection is possible
Joint aspiration where indicated
CT scan to assess implant position or rotation
Other imaging for a defined clinical question

The cause should be identified before selecting treatment.

What Is Manipulation Under Anaesthesia?

Manipulation under anaesthesia, commonly called MUA, is a procedure used in selected patients whose knee remains significantly stiff after replacement.

The patient receives anaesthesia so the muscles relax and pain is not felt during the procedure.

The surgeon then carefully bends and straightens the knee to disrupt restrictive adhesions.

MUA:

Does not require a new knee incision in most cases
Commonly takes only a short time
Is often performed as a day-care procedure
Must be followed by continued movement and physiotherapy

The purpose is to improve movement when scar tissue is the principal problem.

Who May Be Considered for MUA?

MUA may be considered when:

Movement remains substantially restricted
Progress has stopped despite appropriate rehabilitation
Scar tissue or adhesions are suspected
Pain and swelling have been addressed
Infection has been excluded
No major implant-position problem is present
The expected functional benefit justifies the procedure

It should not be selected merely because one numerical bending target has not been achieved.

The patient’s functional limitation and overall progress are important.

Timing of Manipulation

When MUA is appropriate, earlier intervention—commonly within approximately three months of the replacement—may provide more predictable improvement than much later manipulation.

However, timing should not be determined by the calendar alone.

The surgeon should consider:

Current range of motion
Rate of progress
Swelling
Pain
Wound healing
Cause of stiffness
Bone quality
Medical fitness
Previous surgery

Later manipulation may still be considered, but additional investigation may be needed and the result can be less predictable.

What Happens After MUA?

After manipulation, the knee may be:

Painful
Swollen
Bruised
Temporarily more difficult to exercise

Continued rehabilitation is important because scar tissue can reform.

The postoperative plan may include:

Pain control
Cold therapy
Swelling management
Frequent range-of-motion exercises
Supervised physiotherapy
Walking
A continuous passive-motion machine in selected protocols

A CPM machine is not required for every patient.

Risks of Manipulation

Potential risks include:

Continued stiffness
Reformation of scar tissue
Persistent pain
Swelling
Bleeding
Fracture
Ligament or tendon injury
Wound-related problems
Anaesthetic complications

Fracture is uncommon but may be more concerning when there is:

Osteoporosis
Poor bone quality
Long-standing stiffness
Complex implants
Previous fracture
Delayed manipulation

The expected benefit and risks should be discussed individually.

What if Manipulation Does Not Work?

MUA may provide inadequate improvement when stiffness is caused by:

Implant malposition
Incorrect implant size
Infection
Major instability
Severe established arthrofibrosis
Reformed scar tissue
Mechanical obstruction
Long-standing contracture

Further treatment may include:

Continued targeted rehabilitation
Additional investigation
Arthroscopic scar-tissue release in selected cases
Open scar-tissue release
Revision knee replacement when a correctable implant problem exists

A repeat procedure should not be performed without reconsidering the cause.

When Is Revision Knee Replacement Needed?

Revision may be considered when stiffness is caused by a defined mechanical problem such as:

Implant malposition
Incorrect component size
Severe instability
Joint-line alteration
Implant loosening
Infection
Major bone or soft-tissue problem

Revision is not appropriate merely because the knee has not achieved a desired bending angle.

It is more complex than primary replacement and should have a clear objective.

Read Revision Knee Replacement in Mumbai.

Can Robotic Surgery Prevent Stiffness?

Robotic assistance may support:

Surgical planning
Bone preparation
Implant positioning
Alignment measurement
Ligament-balance assessment

It cannot eliminate stiffness caused by:

Swelling
Pain
Scar-tissue tendency
Infection
Limited preoperative movement
Inadequate rehabilitation
Individual healing

Robotic knee replacement does not guarantee a particular range of motion.

Read Robotic Knee Replacement in Mumbai.

Stiffness After Partial or Total Replacement

Partial Knee Replacement

Partial replacement may preserve more natural bone and ligament function and may permit a faster early recovery in suitable patients.

Stiffness may still occur because of:

Pain
Swelling
Scar tissue
Progression of arthritis
Implant problems

Read Partial Knee Replacement in Mumbai.

Total Knee Replacement

Total replacement involves more extensive joint resurfacing and rehabilitation.

Read Total Knee Replacement in Mumbai.

Warning Signs With Stiffness

Contact the treating team promptly when stiffness is accompanied by:

Increasing pain
Increasing swelling
Redness
Wound drainage
Persistent fever
Chills
Repeated knee giving way
New weakness or numbness
Sudden loss of movement
A fall followed by inability to bear weight

Sudden chest pain, breathlessness or a cold and pale foot requires emergency care.

Why Patients Consult Dr. Mayur Rabhadiya

Dr. Mayur Rabhadiya follows a cause-based approach to stiffness after knee replacement.

His assessment emphasises:

Measuring both bending and straightening
Reviewing preoperative movement
Assessing pain and swelling
Checking rehabilitation technique
Evaluating implant position and stability
Excluding infection when indicated
Identifying arthrofibrosis
Considering MUA at an appropriate stage
Avoiding repeated forceful treatment without diagnosis
Recommending revision only for a defined correctable problem

Stiff Knee-Replacement Consultation in Ghatkopar, Mumbai

Diabplus Clinic, Ghatkopar East

601, 6th Floor, Skyline Status, Mahatma Gandhi Road, opposite Pooja Hotel, Pant Nagar, Ghatkopar East, Mumbai, Maharashtra 400077.

Visit Dr. Mayur Rabhadiya in Ghatkopar East.

Savla Clinic, Ghatkopar West

2/3, Dharmodaya Building, next to Raj Medical, near NULife Hospital, Jivdaya Lane, Ghatkopar West, Mumbai, Maharashtra 400086.

Visit Dr. Mayur Rabhadiya in Ghatkopar West.

Frequently Asked Questions

Is stiffness normal after knee replacement?

Some early stiffness is expected because of pain and swelling. It should generally improve with recovery and rehabilitation.

How long does stiffness last?

It varies. Mild activity-related stiffness may continue for several months, but persistent severe restriction should be reviewed.

Why is my knee not bending?

Possible causes include swelling, pain, preoperative stiffness, muscle guarding, scar tissue, infection or a mechanical implant problem.

Why can I not straighten my knee?

Swelling, muscle weakness, soft-tissue tightness and a pre-existing flexion deformity may contribute.

What is arthrofibrosis?

Arthrofibrosis is excessive scar-tissue formation that restricts movement and may cause pain.

Can physiotherapy treat stiffness?

Yes, particularly when stiffness is related to swelling, weakness and early scar formation.

Should physiotherapy be painful?

Some discomfort is expected, but severe force causing prolonged pain and swelling should be avoided.

What is manipulation under anaesthesia?

It is a procedure in which the surgeon bends and straightens the knee under anaesthesia to break restrictive adhesions.

When is MUA considered?

It may be considered when movement remains significantly limited despite appropriate rehabilitation and other causes have been excluded.

When is the best time for MUA?

When appropriate, results are generally more predictable when it is performed within approximately three months of surgery.

Can MUA be performed later?

Yes, but results may be less reliable and additional investigation may be required.

Does manipulation require an incision?

Usually no new knee incision is required.

Is physiotherapy necessary after MUA?

Yes. Continued movement and rehabilitation are important to reduce recurrence of stiffness.

Can scar tissue return?

Yes. Adhesions may reform, particularly if movement is not maintained.

What are the risks of MUA?

Risks include persistent stiffness, pain, swelling and, rarely, fracture or soft-tissue injury.

When is revision surgery needed?

Revision may be considered when stiffness results from infection, implant malposition, instability or another defined mechanical problem.

Can robotic surgery prevent stiffness?

No. Robotics cannot eliminate swelling, pain, scar formation, infection or rehabilitation-related causes.

When should I seek a second opinion?

A second opinion is useful when stiffness is not improving, repeated forceful therapy has failed or MUA or revision surgery has been advised.

About the Author

Dr. Mayur Rabhadiya
Orthopedic & Joint Replacement Surgeon

Qualifications

MBBS
D’Ortho
DNB Orthopedics
MNAMS Orthopedics
Fellowship in Robotic & Computer-Navigated Joint Replacement

Clinical focus

Stiffness after knee replacement
Arthrofibrosis assessment
Manipulation under anaesthesia
Painful knee-replacement evaluation
Total and partial knee replacement
Robotic-assisted knee replacement
Revision knee replacement

Written and medically reviewed by: Dr. Mayur Rabhadiya
Last medically reviewed: June 2026

Clinical References

Book a Stiff Knee-Replacement Assessment

Consultation may be useful if:

Knee movement is not improving
The knee cannot straighten adequately
Bending remains severely restricted
Movement gained during physiotherapy is being lost
The knee is increasingly painful or swollen
Manipulation under anaesthesia has been advised
Previous manipulation did not provide sufficient benefit
Revision surgery has been suggested
The cause of stiffness remains unclear
You require a second opinion

Book an orthopedic consultation with Dr. Mayur Rabhadiya in Ghatkopar, Mumbai

Call or WhatsApp

+91 84249 03913
+91 96113 30063

Medical Disclaimer

This page provides general patient education and does not replace examination by the operating surgeon or another qualified orthopedic specialist. The appropriate treatment for stiffness depends on movement, pain, swelling, infection risk, implant position, bone quality and time since surgery. Seek prompt assessment for increasing pain, wound drainage, fever, progressive redness, sudden loss of movement or inability to bear weight. Sudden chest pain, breathlessness or a cold and pale foot requires emergency care.