It’s not uncommon for patients to notice clicking or tapping sounds in their knee after a total knee replacement (TKR). Understandably, it can be unsettling — especially when the new joint feels or sounds different from your natural knee. The good news is that, in most cases, these noises are completely normal and not a sign of implant failure or a problem with your surgery.

As specialists in knee surgery and regenerative orthopaedics, we often reassure patients that a little “click” can simply mean your new joint is working exactly as designed.

Understanding What Causes the Clicking Sound

A total knee replacement involves resurfacing the worn-out joint surfaces of the femur (thigh bone) and tibia (shin bone) with precisely engineered metal and plastic components. These implants glide smoothly on one another, replacing the damaged cartilage that used to cushion the joint.

When you bend or straighten your knee after surgery, the new mechanical surfaces sometimes produce audible or tactile sensations — most commonly described as:

• Clicking

• Tapping

• Clunking

• Snapping

These sensations usually come from the interaction between the implant components, tendons, and surrounding soft tissues as they adapt to your new knee alignment and movement pattern.

The Most Common Benign Causes

1. Normal Implant Mechanics
   Your new knee is a mechanical system. The metal and plastic parts have firm, well-defined edges, and when they come into contact or move through their range of motion, you may hear a clicking sound. This is especially noticeable during activities such as climbing stairs, getting up from a chair, or walking on hard flooring.

2. Reduced Soft Tissue Cushioning
   After joint replacement, the natural cartilage and meniscus (which normally provide soft, silent cushioning) are replaced by synthetic materials. The absence of these tissues means small sounds that were previously absorbed can now be heard.

3. Scar Tissue and Post-Operative Tightness
   In the early months after surgery, scar tissue forms as part of normal healing. When tendons or ligaments glide over these areas, a snapping or clicking can occur. As your knee becomes more flexible and your quadriceps strengthen, this usually diminishes.

4. Patellar (Kneecap) Tracking
   If the kneecap is slightly out of alignment or if the surrounding muscles are imbalanced, the patella can make a clicking sound as it moves within its new groove. Targeted physiotherapy can often improve this by restoring balance and tracking.

When Clicking Might Need Further Evaluation

Although most clicking is harmless, it’s important to recognise when the sound could indicate an underlying issue. Seek a specialist review if you experience:

• Painful clicking or grinding

• Sudden onset of loud mechanical noises after a fall or twist

• Instability or “giving way” of the knee

• Redness, warmth, or swelling around the joint

• Reduced range of motion or stiffness after initial improvement

These symptoms may suggest loose components, infection, or patellar maltracking, which require professional assessment. A simple X-ray or motion analysis can usually confirm whether the implant remains well fixed and aligned.

The Role of Muscle Strength and Motion Control

One of the key factors influencing knee noise after replacement is muscle control. Following surgery, temporary weakness of the quadriceps and hamstrings changes the way forces are distributed through the knee. As your rehabilitation progresses and muscle tone returns, the clicking often fades away.

At the London Cartilage Clinic and MSK Doctors, we use advanced motion capture analysis (MAI Motion®) and force plate technology to assess each patient’s recovery in detail. This allows us to:

• Identify subtle imbalances in gait and strength

• Adjust physiotherapy programmes precisely

• Predict long-term functional outcomes

By improving the way you move, we can often eliminate unnecessary noise and restore natural, confident knee motion.

Modern Implant Design and “Silent” Solutions

Not all knee implants are the same. Modern designs aim to mimic the anatomy and kinematics of the natural knee, with smoother transitions between components. Some implants incorporate low-friction polyethylene liners or rotating platforms that reduce sound and improve fluidity.

At our centre, implant selection is tailored to the patient’s anatomy, activity level, and bone structure — often using robotic planning and patient-specific guides to optimise alignment. The result is a quieter, more natural-feeling knee that moves in harmony with your body.

Can Regenerative Medicine Help?

While regenerative medicine cannot alter the mechanics of a knee prosthesis, it plays a role in supporting soft tissue recovery around the joint. Treatments such as platelet-rich plasma (PRP), shockwave therapy, or infrared rehabilitation can help improve muscle function, tendon health, and circulation — all of which contribute to smoother, more coordinated movement.

This integrative approach is part of our “Regeneration by Design” philosophy: combining surgical precision with biological optimisation for the best long-term outcome.

Practical Tips to Reduce Clicking Sensations

1. Stay Consistent with Physiotherapy
   Focus on quadriceps and hip strengthening, as muscle control is the key to stable and smooth movement.

2. Maintain a Healthy Weight
   Reducing excess load minimises joint stress and can lessen both sound and discomfort.

3. Monitor Footwear and Gait
   Supportive shoes and balanced walking patterns help distribute forces evenly across the joint.

4. Don’t Overthink the Sound
   A light click without pain is usually harmless. In most cases, the brain quickly adapts, and you stop noticing it.

When to Seek Specialist Advice

If your clicking is persistent, painful, or accompanied by swelling or instability, it’s worth a professional review. A simple clinical examination and X-ray can rule out serious causes. In rare cases, an MRI or motion scan may be used to assess soft tissue behaviour around the prosthesis.

At London Cartilage Clinic, our orthopaedic and motion analysis team are experts in both surgical and non-surgical knee care. We offer comprehensive assessments to help patients understand their symptoms and regain confidence in their recovery.

Summary

Knee clicking after total knee replacement is usually a normal mechanical event, not a sign of something wrong. It reflects the interaction between well-engineered implant surfaces, tendons, and soft tissues adjusting to their new environment.

As your strength returns and movement patterns normalise, most clicking settles naturally. However, if the noise is painful or associated with instability, it’s important to have it checked by a specialist.

At London Cartilage Clinic, we combine advanced imaging, motion analysis, and regenerative rehabilitation to ensure your new knee performs — and feels — as naturally as possible.