Partial Knee Replacement Treatment

It is not suitable for widespread arthritis affecting multiple compartments. In such cases, a total knee replacement may be considered more appropriate. Speak to your orthopaedic surgeon or a qualified partial knee replacement surgeon about which option suits your condition.

Who Can Have a Partial Knee Replacement?

Orthopaedic evaluation

To determine whether this procedure is appropriate, your orthopaedic surgeon will carry out a comprehensive evaluation. This typically includes:

• X-rays or MRI scans
• Physical examination of knee movement, alignment, and stability
• Discussion of your pain levels and impact on daily life

Imaging helps confirm that arthritis is isolated to one compartment and that other parts of the knee, including cartilage and ligaments, are healthy enough to leave intact.

Suitable candidates

You may be considered for partial knee replacement if:

• Only one compartment of your knee is affected
• You have stable ligaments, particularly the anterior cruciate ligament (ACL)
• Your knee is not significantly misaligned (knock-kneed or bow-legged)
• You are moderately active with reasonable expectations

Suitable candidates often include individuals who enjoy walking, gardening, or recreational cycling but do not participate in high-impact or contact sports. Its main aim is to ease pain and support everyday movement, rather than meet the physical demands of intense athletic performance.

Patients with normal weight or mild obesity may still be suitable if their joints are otherwise healthy. Longevity of the implant may be influenced by physical demand and loading patterns.

Patients who are willing to limit high-impact activities after surgery may also be considered if their joint structure and symptoms meet criteria.

Who is not a candidate?

Partial knee replacement may not be suitable if:

• You have inflammatory arthritis (e.g. rheumatoid arthritis)
• You experience significant pain across the entire knee
• Your knee is unstable or has a major deformity
• You are highly active in impact sports

In many cases, your surgeon will assess this through imaging, physical exam, and sometimes diagnostic arthroscopy, a minimally invasive method used to inspect the joint before surgery is planned.

Benefits and Limitations of Partial Knee Replacement

Advantages

• Quicker recovery: Smaller incisions and less tissue disruption mean a shorter hospital stay and faster rehabilitation.
• More natural movement: By retaining most of your original knee structures, many people find the joint feels more “normal” after recovery.
• Lower risk of complications: Studies suggest reduced blood loss and lower risk of deep vein thrombosis compared to total knee replacement.
• Preservation of bone and ligaments: This allows for potential future procedures if needed.
• Less postoperative stiffness: Patients often experience greater range of motion after a partial replacement than after a full knee replacement.
• Natural knee movement: Because more of your knee is preserved, patients often describe the joint as feeling closer to their original knee than after total replacement.

Disadvantages

• This procedure isn’t suitable for every patient: The decision depends heavily on knee anatomy and arthritis pattern. It may also carry a slightly higher risk of needing revision surgery if arthritis progresses in untreated areas of the joint.
• Potential for future surgery: If arthritis spreads to other compartments, a total knee replacement may be needed later.
• More technically demanding: It requires precise surgical technique and careful patient selection for the best outcome.
• Risk of persistent symptoms: Some patients may experience pain unrelated to the replaced compartment, especially if joint degeneration progresses over time.

How Common Is Partial Knee Replacement in Australia?

Partial knee replacement has become increasingly common in Australia, particularly as surgical imaging and robotic assistance improve precision. According to the 2024 AOANJRR, partial knee replacements made up only 7.1% of all knee replacement procedures in 2023, reflecting a continued decline in use nationwide.

This trend reflects improvements in surgical technique and patient selection. Outcomes are best when the procedure is performed by surgeons with high-volume experience in partial knee replacement.

The decision to offer partial versus total knee replacement varies between surgeons and hospitals. Some orthopaedic specialists, including experienced knee surgeons in Sydney, may offer minimally invasive or robotic-assisted procedures to further improve outcomes.

Preparing for Your Partial Knee Replacement

Pre-operative assessment

Your surgeon may organise:

• Blood tests and ECG
• Imaging to confirm the joint damage location
• Medical clearance from your GP or specialist

Optimising your health before surgery, such as managing blood sugar, quitting smoking, or adjusting medications can reduce the risk of complications and support recovery.

Other pre-surgery steps may include strengthening exercises and improving general fitness to assist with rehabilitation after surgery.

Home preparation

Plan ahead for:

• Help with transport and daily tasks during early recovery
• A walker or crutches for initial mobility
• Adjusting home layouts to reduce fall risks

Installing grab rails, elevating seating, and decluttering walkways can make your return home safer and smoother. These simple adjustments are particularly helpful during the first 2–4 weeks post-surgery when mobility is still limited.

What Happens During the Procedure?

Surgical steps

• The operation is typically performed under spinal or general anaesthesia.
• A small incision is made over the affected part of the knee.
• Damaged cartilage and bone are removed.
• A metal and plastic implant is inserted to restore smooth joint function.

Robotic-assisted techniques may be used in some cases to enhance accuracy. Understanding how robotic knee surgery works can provide insight into how these systems map the joint in real time and guide alignment during the procedure. This level of accuracy is particularly valuable in partial knee surgery, where small deviations can affect how weight is distributed, potentially shortening the lifespan of the implant.

Robotic systems can also allow the surgeon to preserve more natural anatomy by reducing variability during bone preparation and component placement.

Procedure length

A partial knee replacement usually takes 1 to 2 hours, and many patients go home the same day or within 24 hours, depending on their health and hospital policies.

Hospital pathways often include enhanced recovery protocols, with early mobilisation and discharge planning built into the care process.

After Surgery: What to Expect in the Hospital

Immediate recovery

After surgery, you will:

• Be monitored in the recovery area
• Begin walking (often within the same day) with help from physiotherapists
• Receive medications for pain and blood clot prevention

Nurses and allied health staff will assist you with mobility and teach you how to safely perform daily tasks before discharge.

Mobilisation

Crutches or a walker will be used initially. Many people are able to move independently within a few days, depending on pain and strength. You may be encouraged to walk short distances multiple times a day to support circulation and healing.

To help lower the risk of blood clots in the early stages of recovery, your care team may recommend blood-thinning medication or provide compression garments such as stockings.

Recovery and Rehabilitation After a Partial Knee Replacement

Recovery timeline

• 0–2 weeks: Focus on wound healing, managing pain, and gentle movement
• 2–6 weeks: Regain walking ability, build strength, return to daily activities
• 6–12 weeks: Resume driving, light duties at work
• 3 months+: Low-impact exercise, return to most activities

The partial knee replacement recovery time varies between individuals, but many people recover more quickly than those who undergo total knee surgery.

Physiotherapy and exercise

Supervised rehabilitation is key to recovery. Your physiotherapist will guide:

• Strength-building around the knee
• Safe range-of-motion exercises
• Strategies to return to stairs, walking, and balance tasks

Hydrotherapy (water-based therapy) may also be recommended during the early stages to reduce joint stress while improving mobility.

Pain management

• Pain usually improves steadily after the first few days
• Ice, elevation, and short-term use of pain medication are often recommended
• If pain worsens or persists, follow up with your care team

It’s important to follow your prescribed pain management plan closely, as good pain control supports earlier mobilisation and more effective physiotherapy — both of which are linked to better long-term outcomes.

Returning to daily activities

• Work: Office-based workers may return after 2–4 weeks. Physically demanding roles may require longer.
• Driving: Usually possible after 4–6 weeks, when you can bend your knee comfortably and react quickly. You must also be able to fully control the leg for braking and acceleration. Some insurance providers require clearance from your healthcare provider before driving post-op.
• Sport: Swimming, cycling, and walking are usually allowed after 3 months. High-impact sports are typically discouraged.

Ask your surgeon before returning to activities like hiking, running, or lifting heavy weights.

Risks and Complications

General surgical risks

• Bleeding
• Infection
• Blood clot (deep vein thrombosis or pulmonary embolism)

Procedure-specific complications

• Implant loosening over time
• Ongoing pain due to arthritis in other knee areas
• Stiffness or reduced mobility
• Need for revision surgery in future years

When to contact your doctor

Call your healthcare provider if you experience:

• Redness or discharge around the wound
• Fever or chills
• Sudden pain or swelling in the leg
• Difficulty walking or straightening your knee

Prompt care can prevent serious complications.

How Long Does a Partial Knee Replacement Last?

Many partial knee replacements last 10 to 15 years or more, particularly in lower-impact patients. Longevity depends on:

• Your activity levels
• Body weight
• Implant type and positioning
• How well you follow rehabilitation advice

You may need further imaging or a follow-up procedure if symptoms return over time.

Is Partial Knee Replacement a Good Option for Me?

In carefully selected patients, partial knee replacement offers excellent outcomes. Research shows high satisfaction rates, with many people reporting improved mobility and reduced pain. However, not every knee problem qualifies.

The success of this procedure depends on:

• Accurate diagnosis
• Skilled surgical technique
• Commitment to rehabilitation

Studies from institutions such as the Australian Orthopaedic Association support its effectiveness when used appropriately.

Partial vs Total Knee Replacement: Which One Should I Choose?

Partial knee replacement is not inherently “better” than total knee replacement. Each approach has different indications.

• Partial Knee Replacement - Total Knee Replacement
• Only one compartment was replaced - Entire knee joint was replaced
• Quicker recovery - Longer hospital stay and rehab
• More natural knee movement - More comprehensive solution
• May need revision later if arthritis spreads - Usually lasts 15–20+ years

Note: Neither procedure is universally better. Suitability depends on your joint condition, goals, and lifestyle. Your orthopaedic surgeon will recommend the best option based on your individual case.

Follow-Up and Long-Term Care

After surgery, you’ll attend routine reviews to check:

• Wound healing
• Knee alignment and range of motion
• Implant position (via X-rays)

These reviews are usually scheduled:

• 2 weeks post-op
• 6 weeks
• 3 months
• Annually (or as needed)

Report any changes in your symptoms between appointments.

What to Know Before You Decide

Partial knee replacement is a valuable option for Australians with arthritis limited to one part of the knee. It offers faster recovery, less disruption to the body, and more natural function, provided the knee joint is otherwise healthy and stable.

For some, that decision begins with recognising changes in knee comfort or function—being aware of the early warning signs of knee arthritis may help prompt earlier intervention or referral before symptoms become more advanced.

This partial knee replacement treatment is not suitable for everyone. A personalised evaluation with a knee surgeon located in Sydney or your nearest orthopaedic specialist is essential to determine if it’s the right choice for your condition.

Book a Consultation

If you’re considering partial knee replacement and want to know if it’s suitable for your condition, Dr Jonathan Negus and his team offer evidence-based care focused on preserving your natural joint movement and supporting confident recovery
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