Partial Knee Replacement (Uni-compartmental Knee Replacement — UKR)

Not every patient with knee arthritis requires a Total Knee Replacement. If arthritis is confined to only one part of the knee, a Partial Knee Replacement (Uni-compartmental Knee Replacement or UKR) may be an excellent alternative.

This advanced procedure replaces only the damaged compartment of the knee while preserving healthy cartilage, ligaments and bone. By retaining much of your natural knee, UKR often provides a more natural-feeling joint, quicker recovery and excellent long-term outcomes in appropriately selected patients.

At the Knee Centre, Dr Anand Jadhav specialises in patient-specific assessment to determine whether Partial Knee Replacement or Total Knee Replacement is the most appropriate treatment for each individual.

What is a Partial Knee Replacement?

The knee is divided into three compartments:

• Medial (Inner) Compartment
• Lateral (Outer) Compartment
• Patellofemoral (Kneecap) Compartment

In many patients, arthritis affects only one of these compartments. Instead of replacing the entire knee, a Partial Knee Replacement resurfaces only the damaged area using specially designed metal and highly durable polyethylene implants while preserving the healthy parts of the joint.

Who is a Candidate for Partial Knee Replacement?

Partial Knee Replacement is recommended for carefully selected patients with:

• Advanced arthritis confined to a single compartment of the knee
• Intact ACL, PCL and collateral ligaments
• Good knee stability
• Good range of knee movement
• Healthy cartilage in the remaining compartments
• Persistent pain despite comprehensive non-surgical treatment

Appropriate patient selection is one of the most important factors influencing long-term success.

When is a Total Knee Replacement a Better Option?

Total Knee Replacement is better than Partial Knee Replacement for patients with:

• Arthritis affecting all compartments of the knee
• Rheumatoid or inflammatory arthritis
• Significant knee deformity
• Severe knee stiffness
• Ligament instability
• Advanced patellofemoral arthritis
• Active infection
• Certain neuromuscular disorders

A thorough clinical assessment and imaging help determine the most appropriate treatment for each patient.

Advantages of Partial Knee Replacement

Compared with Total Knee Replacement, Partial Knee Replacement offers several important benefits in the right patient.

Preservation of Healthy Knee Structures

Only the damaged compartment is replaced, preserving healthy bone, cartilage and ligaments.

More Natural Knee Movement

Because the knee's own ligaments are retained, many patients report that the knee feels more natural during everyday activities.

Smaller Incision

The procedure is performed through a smaller surgical incision with less disruption of surrounding tissues.

Faster Recovery

Patients generally experience:

• Less postoperative pain
• Reduced blood loss
• Earlier mobilisation
• Shorter hospital stay
• Faster return to daily activities

Better Range of Motion

Many patients achieve excellent knee bending and overall function after rehabilitation.

Easier Future Revision

If arthritis progresses in other compartments many years later, conversion to a Total Knee Replacement is generally straightforward.

Mobile Bearing vs Fixed Bearing UKR

Modern Partial Knee Replacements are available in two principal designs.

Mobile Bearing UKR

The polyethylene insert is free to move slightly between the metal components, allowing:

• More natural knee mechanics
• Excellent conformity between the joint surfaces
• Lower wear rates
• Potentially longer implant longevity in selected patients

Fixed Bearing UKR

The polyethylene insert is securely fixed to the tibial component, providing:

• Excellent stability
• Technical simplicity
• Reliable long-term results
• Excellent function in appropriately selected patients

The choice of implant depends on the patient's anatomy, activity level, ligament stability and the surgeon's experience.

Robotic Partial Knee Replacement

At the Knee Centre, Partial Knee Replacement can also be performed using robotic-assisted technology in suitable patients. Robotic surgery enables:

• Highly accurate implant positioning
• Precise bone preparation
• Better soft tissue balancing
• Personalised alignment
• Improved implant longevity
• Consistent surgical precision

This technology helps deliver highly individualised treatment while preserving as much natural knee tissue as possible.

Recovery After Partial Knee Replacement

Early mobilisation is one of the major advantages of UKR. Most patients can:

• Stand and begin walking with assistance on the day of surgery or the following morning
• Return home within 1–2 days
• Walk comfortably with support during the early recovery period
• Resume office-based work within 2–3 weeks
• Drive after approximately 4–6 weeks, depending on individual progress
• Return to recreational activities such as walking, cycling and swimming after rehabilitation

A structured physiotherapy programme plays a vital role in restoring strength, movement and confidence.

Long-Term Results of UKR

When performed in the right patient by an experienced surgeon, Partial Knee Replacement has excellent long-term outcomes. Most patients experience:

• Significant pain relief
• Improved walking ability
• Better knee movement
• Faster recovery than Total Knee Replacement
• A more natural-feeling knee
• High patient satisfaction

Modern implants demonstrate excellent durability, with reported survival rates of 95–98% at 10–12 years in appropriately selected patients.

Why Choose Dr Anand Jadhav?

With over 30 years of orthopaedic experience and 12 years of specialist practice in the NHS, United Kingdom, Dr Anand Jadhav has extensive expertise in Joint Preservation, Partial Knee Replacement and Robotic Knee Surgery.

His approach focuses on selecting the least invasive procedure capable of providing the best long-term outcome. Whenever appropriate, he aims to preserve healthy bone, cartilage and ligaments while restoring pain-free movement and helping patients return to an active lifestyle. His areas of expertise include:

• Robotic Partial Knee Replacement
• Robotic Total Knee Replacement
• Knee Arthroscopy
• Joint Preservation Surgery
• High Tibial Osteotomy
• Revision Knee Replacement
• Sports Knee Injuries

Frequently Asked Questions (FAQs)

Is Partial Knee Replacement better than Total Knee Replacement?

Not necessarily. It is better only for the right patient. If arthritis is confined to one compartment, UKR offers excellent results with faster recovery and a more natural-feeling knee. If arthritis affects multiple compartments, Total Knee Replacement is usually the more appropriate option.

How do I know if I am suitable for UKR?

A detailed consultation, clinical examination and weight-bearing X-rays are required to determine whether your arthritis is confined to one compartment and whether your ligaments and remaining cartilage are healthy.

How long does a partial knee implant last?

Modern implant designs and precise surgical techniques give unicondylar implants excellent long-term survival rates — with over 90% of partial knee replacements continuing to function well beyond 15 to 20 years.

Can a Partial Knee Replacement be converted to a Total Knee Replacement later?

Yes. If arthritis progresses in the remaining compartments over time, a Partial Knee Replacement can usually be revised to a Total Knee Replacement when necessary.