Patellar resurfacing: Definition, Uses, and Clinical Overview

Posted on February 28, 2026 | by drknee

Patellar resurfacing Introduction (What it is)

Patellar resurfacing is a surgical step in knee replacement where the joint surface on the back of the kneecap (patella) is replaced with an implant.
In plain terms, it “re-caps” the underside of the kneecap so it can glide more smoothly against the new knee joint.
It is most commonly discussed in the setting of total knee arthroplasty (total knee replacement).
Whether it is done routinely or selectively varies by clinician and case.

Why Patellar resurfacing used (Purpose / benefits)

The patella is part of the patellofemoral joint, where the kneecap tracks in a groove on the femur (thigh bone). In arthritis and some other knee conditions, the cartilage on the back of the patella can become worn, rough, and painful. During total knee replacement, the femur and tibia (shin bone) joint surfaces are replaced, but the patella surface may be either left alone or resurfaced.

Patellar resurfacing is used to address symptoms and mechanics related to the patellofemoral joint. In general terms, clinicians consider it to:

Reduce pain that is thought to come from the kneecap surface (often described as “anterior knee pain,” meaning pain in the front of the knee).
Improve the smoothness of kneecap motion against the femoral component after knee replacement.
Provide a more uniform artificial bearing surface when the native patellar cartilage is severely damaged.
Potentially reduce the chance of needing a later surgery to resurface the patella (secondary resurfacing), although the likelihood varies by clinician and case.

It is important to understand that outcomes depend on multiple factors—not only the patellar surface itself, but also limb alignment, soft-tissue balance, component positioning, and rehabilitation participation.

Indications (When orthopedic clinicians use it)

Typical scenarios where clinicians may consider Patellar resurfacing include:

Advanced cartilage wear or bone-on-bone changes on the back of the patella seen during surgery or on imaging
Significant patellofemoral arthritis contributing to symptoms
Inflammatory arthritis (such as rheumatoid arthritis) with widespread joint surface damage
Prior symptoms strongly localized to the front of the knee, when the clinical picture suggests patellofemoral involvement
Revision knee arthroplasty settings where the patella surface is a suspected pain generator
Situations where the surgeon’s implant system and alignment plan are designed with resurfacing as a standard approach (varies by clinician and case)

Contraindications / when it’s NOT ideal

Patellar resurfacing is not always appropriate. Situations where it may be less suitable, or where another approach may be considered, include:

A patella that is too thin or has poor bone quality, increasing risk of fracture or fixation problems
Severe patellar bone loss, cysts, or prior surgery that compromises structural support
Active or suspected infection around the joint (implanting additional components is generally avoided)
Major extensor mechanism problems (quadriceps tendon, patella, or patellar tendon dysfunction) where resurfacing does not address the primary issue
Marked maltracking or instability that is not correctable with balancing and alignment during the primary procedure (resurfacing alone does not “fix” tracking)
Hypersensitivity or intolerance concerns related to implant materials (management varies by material and manufacturer)
Cases where the patellar cartilage is relatively preserved and the clinician judges resurfacing to add risk without clear benefit (varies by clinician and case)

How it works (Mechanism / physiology)

The basic biomechanical idea

The patella acts like a pulley for the quadriceps muscle, improving leverage for knee extension. When the knee bends and straightens, the back of the patella glides against the femur’s trochlear groove. A smooth, congruent interface helps distribute forces and reduces focal stress.

Patellar resurfacing changes the bearing surface on the underside of the kneecap. The goal is to create a smoother articulation between:

The resurfaced patella component (often a polyethylene “button,” design varies), and
The femoral component’s trochlear region in a total knee replacement.

Key anatomy involved

Patella (kneecap): A sesamoid bone embedded in the quadriceps tendon; its underside is covered with articular cartilage in a native knee.
Femur: The thigh bone; the front has a groove (trochlea) where the patella tracks.
Tibia: The shin bone; forms the main hinge portion of the knee with the femur.
Articular cartilage: Smooth tissue coating joint surfaces; when worn, it can contribute to pain and mechanical symptoms.
Extensor mechanism: Quadriceps tendon, patella, and patellar tendon working together to straighten the knee.
Soft tissues affecting tracking: Retinaculum, capsule, and muscle balance influence patellar alignment and motion.

The menisci and major ligaments (ACL, PCL, collateral ligaments) are central to overall knee stability, but Patellar resurfacing primarily targets the patellofemoral surface rather than replacing ligaments or meniscus tissue.

Onset, duration, and reversibility

Patellar resurfacing is not a medication or temporary therapy; it is an implant-based surgical modification. Its effects are intended to be long-lasting, but longevity depends on implant design, fixation method, positioning, patient factors, and wear over time (varies by material and manufacturer). Reversibility is limited; while components can be revised, revision surgery is a separate procedure with its own considerations.

Patellar resurfacing Procedure overview (How it’s applied)

Patellar resurfacing is typically performed as part of a total knee replacement, though it can also be done later as a “secondary resurfacing” in selected cases. A high-level workflow often looks like this:

Evaluation / exam – History of symptoms (including front-of-knee pain), prior treatments, functional limitations – Physical exam focusing on alignment, range of motion, stability, and patellar tracking
Imaging / diagnostics – Standard knee X-rays to assess arthritis pattern and alignment – Additional imaging when needed to evaluate bone quality or other structures (varies by clinician and case)
Preparation / planning – Preoperative planning for component sizing and alignment in knee arthroplasty – Discussion of whether the patella may be resurfaced, depending on intraoperative findings and surgeon preference
Intervention – During knee replacement, the surgeon assesses the patella’s cartilage and bone – If resurfacing is chosen, the undersurface is prepared and an implant is secured (commonly cemented; techniques vary)
Immediate checks – Verification of patellar tracking and stability through the knee’s motion – Assessment of soft-tissue balance and component positioning in the overall arthroplasty construct
Follow-up / rehab – Postoperative monitoring for wound healing, swelling, range of motion, gait, and function – Rehabilitation focusing on restoring mobility and strengthening the extensor mechanism, guided by the surgical team’s protocol

This overview is intentionally general; exact steps and protocols vary by clinician, implant system, and patient-specific anatomy.

Types / variations

Patellar resurfacing is not one single technique. Common variations include:

Resurfacing vs non-resurfacing (native patella retention)
Some surgeons routinely resurface; others selectively resurface based on patellar cartilage condition and patient factors (varies by clinician and case).
Primary resurfacing vs secondary resurfacing
Primary: done during the initial total knee replacement.
Secondary: performed later if patellofemoral symptoms persist and the patella was not resurfaced initially (careful evaluation is typically needed because pain can have multiple sources).
Implant design variations
All-polyethylene buttons: commonly used; shape and fixation features vary by manufacturer.
Metal-backed designs: used less commonly in many settings; selection depends on implant system and surgeon preference (varies by material and manufacturer).
Medialized or anatomic designs: intended to better match patellar tracking and anatomy; use varies.
Fixation approach
Cemented fixation: frequently used for patellar components.
Other fixation concepts: depend on design; availability and indications vary by manufacturer and case.
Associated patellar procedures (often discussed alongside resurfacing)
Patelloplasty: shaping/smoothing without placing an implant.
Denervation: cauterizing small nerve fibers around the patella to reduce pain signals (use and effectiveness vary by clinician and case).
Lateral release or soft-tissue balancing: performed when needed to improve tracking; not inherently part of resurfacing but can be related.

Pros and cons

Pros:

May reduce pain originating from damaged patellar cartilage in selected patients
Creates an artificial bearing surface intended to glide more smoothly against the femoral component
Can be performed during the primary knee replacement without requiring a separate operation
May reduce the likelihood of needing later secondary resurfacing in some practices (varies by clinician and case)
Allows the surgeon to address patellofemoral arthritis at the same time as tibiofemoral arthritis
Provides a standardized surface when native cartilage condition is poor

Cons:

Adds another implant interface, which can introduce risks such as loosening or wear over time (varies by material and manufacturer)
Risk of patellar fracture, especially with thin bone stock or technical challenges
Potential for maltracking, instability, or clunking symptoms if overall alignment and soft-tissue balance are suboptimal
Not all anterior knee pain after knee replacement is caused by the patellar surface; resurfacing may not address non-patellar pain sources
Can complicate future revision surgery compared with leaving the native patella untouched
Implant-related complications (component failure, wear, fixation issues) are possible, with risk influenced by technique and patient factors

Aftercare & longevity

Aftercare is usually framed within the broader total knee arthroplasty recovery. The patella is part of the extensor mechanism, so rehabilitation often emphasizes restoring knee motion and rebuilding quadriceps strength in a staged way determined by the surgical team.

Factors that commonly influence outcomes and longevity include:

Severity and pattern of arthritis: More extensive patellofemoral damage may affect preoperative pain patterns and postoperative expectations.
Component positioning and limb alignment: Patellar tracking depends on how femoral and tibial components are placed and how soft tissues are balanced.
Patellar thickness and bone quality: Adequate remaining bone helps support fixation and reduce fracture risk.
Rehabilitation participation: Regaining quadriceps strength and coordinated movement can influence function and symptoms.
Weight-bearing status and activity level: These are typically guided by the surgical plan; long-term joint loading patterns can influence wear.
Comorbidities: Conditions affecting bone health, wound healing, or neuromuscular control can affect recovery and implant durability.
Implant design and material characteristics: Wear behavior and fixation performance vary by material and manufacturer.

Longevity is not a fixed number. It depends on patient-specific biomechanics, implant factors, and postoperative course, and it can differ even among people with similar surgeries.

Alternatives / comparisons

Patellar resurfacing is usually considered within a larger decision: how best to address patellofemoral disease in the context of knee pain and arthritis.

Common alternatives or comparison points include:

Leaving the patella unresurfaced (patellar retention)
Often paired with smoothing of rough cartilage edges and careful balancing.
Avoids implanting a patellar component but may leave damaged cartilage in place.
Some patients do well without resurfacing; others may have persistent anterior knee pain (varies by clinician and case).
Patelloplasty (reshaping without an implant)
May reduce mechanical roughness without adding a component.
Does not replace cartilage; results depend on the underlying cartilage and bone condition.
Non-surgical care for patellofemoral pain (when knee replacement is not indicated)
Physical therapy focused on strength, mobility, and movement patterns
Activity modification, bracing or taping, and symptom-directed medications
Injections are sometimes used for arthritis-related symptoms in certain patients
These approaches may be considered earlier in the care pathway; they do not replace joint surfaces.
Other surgeries depending on diagnosis
Realignment procedures (selected cases of maltracking or instability)
Patellofemoral arthroplasty (partial replacement of the patellofemoral joint) in carefully selected patients
The appropriate comparison depends on whether the main problem is isolated patellofemoral disease or more widespread knee arthritis.

In practice, clinicians weigh symptom patterns, imaging, intraoperative cartilage status, alignment, and patient-specific risks to choose between resurfacing and alternatives.

Patellar resurfacing Common questions (FAQ)

Q: Is Patellar resurfacing the same as a total knee replacement?
Patellar resurfacing is usually one component of a total knee replacement, not the entire operation. Total knee arthroplasty replaces the femur and tibia joint surfaces, and the patella may or may not be resurfaced as part of that procedure. Some patients hear it described as “resurfacing the kneecap.”

Q: Does Patellar resurfacing reduce pain for everyone?
Not necessarily. Front-of-knee pain after knee replacement can come from multiple sources, including soft-tissue irritation, tracking mechanics, muscle weakness, or other joint structures. Whether resurfacing helps depends on the condition of the patellar cartilage, overall alignment, and case-specific factors (varies by clinician and case).

Q: What kind of anesthesia is used?
When done with knee arthroplasty, anesthesia may be general anesthesia, regional anesthesia (such as spinal), or a combination with nerve blocks for pain control. The choice depends on patient factors, surgical plan, and anesthesia team protocols. Specific recommendations are individualized.

Q: How painful is recovery when the patella is resurfaced?
Pain levels vary widely among individuals and depend on the full knee replacement recovery, not only the patella. Early soreness around the front of the knee can occur because the extensor mechanism is involved in movement and rehab. Pain management strategies are part of the overall postoperative plan.

Q: How long do the results last?
Patellar components are intended to be durable, but long-term performance depends on implant design, fixation, alignment, activity level, and wear (varies by material and manufacturer). Some patients may never need additional patellar surgery, while others may develop issues that require evaluation. Longevity is best discussed in general terms rather than guaranteed timelines.

Q: Is it “safer” to resurface or not resurface the patella?
Each approach has potential benefits and risks. Resurfacing can help when patellar cartilage is severely damaged, but it also adds implant-related risks such as loosening, wear, or fracture. Many surgical teams tailor the decision to the patient’s anatomy and the intraoperative findings.

Q: Can Patellar resurfacing be done later if the kneecap wasn’t resurfaced during the first surgery?
In some cases, yes—this is called secondary patellar resurfacing. However, persistent pain after knee replacement is not always due to the patella, so a careful evaluation is typically needed before considering another operation. The decision depends on symptoms, imaging, and overall knee mechanics.

Q: Will I be able to drive or return to work quickly?
Timelines vary based on which leg was operated on, pain control, mobility, reaction time, and the type of work involved. Driving and work return are usually discussed as part of the broader total knee replacement recovery plan. Your surgical team typically provides criteria-based guidance rather than a one-size-fits-all schedule.

Q: Will I be allowed to bear weight right away?
Weight-bearing plans are determined by the overall knee replacement procedure and any additional factors identified during surgery. Many patients progress to weight-bearing relatively early, but protocols vary by clinician, implant system, and individual circumstances. Always interpret general information through the lens of the treating team’s protocol.

Q: Does Patellar resurfacing change knee strength or stability?
Resurfacing mainly changes the joint surface of the patella; it is not a ligament reconstruction and does not directly “tighten” the knee. Stability after knee replacement is primarily influenced by the implant design, ligament balance, and alignment. Strength depends heavily on rehabilitation and restoration of quadriceps function.