Knee Replacement: Understanding, Recovering, and ImprovingMobility

Knee replacement surgery is a common procedure used to reduce pain, improve
mobility, and restore physical function in individuals experiencing significant damage to
the knee joint. While knee replacement can provide substantial improvements in pain
and movement, rehabilitation and ongoing exercise play an important role in helping
individuals regain strength, mobility, confidence, and independence.
Accredited Exercise Physiologists can play an important role in supporting individuals
before and after knee replacement surgery by developing safe, progressive, and
individualised exercise programs. Exercise can assist with rebuilding muscle strength,
improving physical capacity, restoring functional movement, and supporting a return to
everyday activities.

What Is a Knee Replacement?
A knee replacement, also known as knee arthroplasty, is a surgical procedure in which
damaged surfaces of the knee joint are replaced with artificial components.
The knee is a complex joint that allows the leg to bend, straighten, and support the body
during activities such as walking, standing, climbing stairs, and sitting.
During knee replacement surgery, damaged areas of the knee may be replaced with
artificial components designed to restore the function of the joint.
The goals of knee replacement surgery generally include:

• Reducing knee pain
• Improving knee movement
• Improving walking ability
• Improving physical function
• Supporting greater independence
• Improving quality of life

Why Do People Need a Knee Replacement?
Knee replacement is generally considered when significant knee damage causes
persistent pain and functional limitations that have not been adequately managed with
non-surgical treatment.

Common reasons for knee replacement include:

• Osteoarthritis
• Rheumatoid arthritis
• Other inflammatory forms of arthritis
• Significant previous knee injury
• Joint damage associated with trauma
• Other conditions causing substantial damage to the knee joint
  Individuals may experience increasing difficulty with walking, stairs, standing, getting
  up from a chair, exercise, work, and other everyday activities.

Common Symptoms Before Knee Replacement
Knee joint damage can result in a range of symptoms, including:

• Knee pain
• Joint stiffness
• Reduced knee range of motion
• Swelling
• Muscle weakness
• Difficulty walking
• Difficulty climbing stairs
• Difficulty getting up from a chair
• Difficulty standing for prolonged periods
• Reduced participation in exercise and physical activity
• Reduced confidence with movement
• Reduced independence and quality of life
  Persistent pain can lead individuals to reduce their physical activity. Over time, this may
  contribute to muscle weakness, reduced cardiovascular fitness, and physical
  deconditioning.

What Happens After Knee Replacement?
Recovery following knee replacement varies between individuals and depends on
factors such as age, overall health, pre-operative fitness, surgical factors, previous
activity levels, and the presence of other health conditions.
Following surgery, individuals may initially experience:

• Pain and swelling around the knee
• Reduced knee range of motion
• Reduced leg strength
• Difficulty walking
• Changes in walking pattern
• Reduced balance and confidence
• Difficulty with stairs
• Difficulty getting up and down from chairs
• Reduced cardiovascular fitness
• Muscle weakness and deconditioning
  Rehabilitation focuses on gradually restoring movement and function while allowing the
  knee and surrounding tissues to recover.
  The aim is not simply to recover from the surgery, but to progressively rebuild the
  physical capacity required for everyday life.

The Importance of Exercise After Knee Replacement
Exercise is an important component of recovery following knee replacement.
A progressive exercise program can help individuals:

• Rebuild lower-limb strength
• Improve knee range of motion
• Improve walking ability
• Improve balance
• Increase cardiovascular fitness
• Improve functional mobility
• Reduce physical deconditioning
• Improve confidence with movement
• Return to everyday activities
• Increase independence
• Support participation in recreational activities
  Exercise should be introduced progressively and adjusted according to the individual’s
  stage of recovery, symptoms, physical capacity, surgical recommendations, and goals.

Early Rehabilitation
Early rehabilitation generally focuses on restoring basic movement and functional
independence.
Depending on the individual’s circumstances and healthcare team’s recommendations,
early exercises may include:

• Gentle knee range-of-motion exercises
• Ankle movements
• Quadriceps activation exercises
• Straight-leg raises where appropriate
• Gluteal muscle activation
• Supported standing exercises
• Sit-to-stand practice
• Heel raises
• Short periods of walking
  The focus during this stage is on gradually restoring movement and function while
  allowing appropriate recovery following surgery.
  Walking is generally progressed gradually, beginning with shorter distances and
  increasing activity as tolerated.

Improving Knee Range of Motion
Restoring knee movement is an important part of rehabilitation following knee
replacement.
Individuals may experience stiffness and difficulty fully bending or straightening the
knee during the early stages of recovery.
Appropriately prescribed mobility exercises can help individuals work towards restoring
functional knee movement.
Improving range of motion can support activities such as:

• Walking
• Sitting and standing
• Getting in and out of a car
• Climbing stairs
• Getting dressed
• Household activities
• Exercise and recreation
  Mobility exercises should be performed according to the individual’s surgical and
  rehabilitation recommendations and progressed gradually.

Strength Training
Muscle weakness is common following knee replacement and may also have been
present before surgery due to pain and reduced activity.

Strength training can help rebuild the muscles required for walking, stairs, balance,
transfers, and everyday activities.
Exercises may include:

• Sit-to-stands
• Supported squats
• Step-ups
• Leg strengthening exercises
• Knee extension exercises
• Hamstring strengthening
• Calf raises
• Hip strengthening exercises
• Resistance band exercises
• Machine-based resistance exercises where appropriate
  Resistance should be progressively increased as strength, movement, and exercise
  tolerance improve.
  Progressive resistance training can help individuals move beyond basic rehabilitation
  exercises and develop the physical capacity required for everyday life and recreational
  activities.

Improving Walking and Functional Mobility
Walking is an important part of recovery following knee replacement.
Individuals may initially experience changes in their walking pattern due to pain,
swelling, weakness, reduced knee movement, or reduced confidence.
Exercise can help address these factors by improving:

• Leg strength
• Knee mobility
• Balance
• Coordination
• Cardiovascular fitness
• Walking endurance
• Confidence with movement
  Functional exercises such as sit-to-stands, step-ups, controlled squats, and walking
  can help prepare individuals for everyday activities.
  As physical capacity improves, exercise can be progressed to reflect the individual’s
  lifestyle and goals.

Balance and Falls Prevention
Balance can be affected following knee replacement, particularly when an individual
has experienced prolonged pain, muscle weakness, reduced activity, or changes in
walking pattern.
Balance exercises can form an important part of rehabilitation and may include:

• Weight-shifting exercises
• Supported single-leg activities
• Stepping exercises
• Controlled changes of direction
• Functional balance activities
• Lower-limb strengthening
• Walking and obstacle-based activities where appropriate
  Improving strength and balance can help individuals feel more confident when walking
  and performing everyday activities.

Cardiovascular Exercise
Cardiovascular fitness may decrease following knee replacement because physical
activity is often reduced during the recovery period.
Low-impact cardiovascular activities can help gradually rebuild endurance.
Depending on the individual’s recovery and medical recommendations, suitable
activities may include:

• Walking
• Stationary cycling
• Cycling
• Swimming once the surgical wound has appropriately healed
• Other low-impact aerobic activities
  The intensity and duration should be gradually progressed according to the individual’s
  physical capacity and recovery.
  Improving cardiovascular fitness can make everyday activities feel easier and support a
  return to work, recreation, and community participation.

Exercise and Pain Management
Pain and discomfort can occur during the recovery period following knee replacement.
However, persistent, worsening, or unexpected symptoms should be discussed with the
individual’s treating healthcare team.
Fear of movement can sometimes cause individuals to reduce their activity following
surgery. Prolonged inactivity can contribute to muscle weakness, reduced
cardiovascular fitness, stiffness, and loss of confidence.
A carefully structured exercise program can help individuals gradually increase their
tolerance to movement and physical activity.
Exercise should be adjusted according to:

• Pain and discomfort
• Swelling
• Knee range of motion
• Muscle strength
• Fatigue
• Walking ability
• Balance
• Stage of surgical recovery
• Medical and surgical recommendations
• Individual goals and preferences
  The aim is to progressively increase activity while allowing appropriate recovery.

Returning to Everyday Activities
One of the major goals following knee replacement is returning to normal daily
activities.
Exercise can help individuals regain the physical capacity required for:

• Getting in and out of chairs
• Getting in and out of bed
• Walking around the home
• Climbing stairs
• Shopping
• Household activities
• Returning to work
• Driving when medically cleared
• Participating in community activities
• Returning to recreational activities

Functional exercise should reflect the individual’s actual lifestyle and goals.
For example, someone who wants to return to gardening may require different strength,
mobility, balance, and endurance goals compared with someone who wants to return to
golf, swimming, cycling, work, or longer-distance walking.

Returning to Exercise and Sport
Knee replacement does not necessarily mean an individual needs to give up physical
activity.
Many individuals can return to a range of recreational activities following appropriate
rehabilitation. However, the timing and type of activity should be individualised and
discussed with the individual’s healthcare team where appropriate.
Lower-impact activities may be particularly useful for developing long-term physical
activity habits, while higher-impact or more physically demanding activities may require
additional consideration.
Exercise progression may involve:

• Increasing walking distance
• Increasing resistance
• Improving knee mobility
• Improving balance and coordination
• Increasing cardiovascular endurance
• Introducing more complex functional movements
• Gradually returning to preferred recreational activities
  The goal is to develop the strength, mobility, endurance, and confidence required for the
  activities that are meaningful to the individual.

The Role of an Accredited Exercise Physiologist
An Accredited Exercise Physiologist can help individuals safely transition from surgery
and early rehabilitation toward long-term physical activity.
An individualised exercise program may include:

• Strength training
• Cardiovascular exercise
• Knee mobility exercises
• Balance training
• Functional exercises
• Walking programs
• Exercise progression
• Education around physical activity
• Strategies to manage fatigue and recovery
• Support for returning to recreational activities
  Exercise Physiologists can also consider other health conditions, previous injuries,
  current fitness levels, work demands, lifestyle, and individual goals when developing an
  exercise program.
  The goal is not simply to complete rehabilitation exercises, but to help the individual
  develop the physical capacity and confidence required for long-term independence and
  participation.

The Importance of a Holistic Approach
Successful recovery following knee replacement involves more than the surgical
procedure itself.
A holistic approach considers:

• Strength
• Knee mobility
• Balance
• Cardiovascular fitness
• Walking ability
• Pain and symptoms
• Confidence with movement
• Sleep and recovery
• Body weight where appropriate
• Lifestyle
• Work requirements
• Recreational goals
• Long-term physical activity
  Combining these areas can help individuals move from post-operative rehabilitation
  toward maintaining an active and independent lifestyle.

Long-Term Exercise After Knee Replacement
Once the initial recovery period has passed, maintaining regular physical activity
remains important.

Long-term exercise can help individuals maintain:

• Muscle strength
• Cardiovascular fitness
• Knee and lower-limb function
• Balance
• Functional capacity
• Healthy body weight
• Confidence with movement
• Independence
  Exercise should ideally become part of the individual’s regular lifestyle rather than
  something that stops once formal rehabilitation finishes.
  Regular walking, resistance training, cardiovascular exercise, mobility work, and
  recreational activities can all contribute to maintaining physical function.

From Surgery to Independence
Knee replacement can provide an important opportunity to reduce pain and improve
physical function. However, the surgical procedure is only one part of the recovery
process.
Progressive exercise and rehabilitation can help individuals rebuild strength, improve
knee mobility, restore balance, increase physical capacity, and return to the activities
that are important to them.
With appropriate guidance, individualised exercise, and a gradual approach to
progression, individuals can work towards regaining mobility, independence,
confidence, and quality of life following knee replacement.
An Accredited Exercise Physiologist can play an important role in supporting this
process by developing a safe and progressive exercise program that considers the
individual’s recovery, capabilities, lifestyle, and goals.