Minimally Invasive Knee Replacement: What to Know

Executive Summary

• The approach is designed to access and replace the damaged parts of the knee while limiting disruption to surrounding muscles and soft tissues when appropriate.
• Minimally invasive knee replacement surgery still involves preparing the joint and placing replacement components, but the surgical approach and handling of surrounding tissues may differ.
• Robotic technology can support planning, bone preparation, and implant positioning, but it does not automatically make a procedure minimally invasive.
• Anatomy, joint damage, overall health, surgical goals, and the surgeon’s assessment all help determine whether a minimally invasive approach is appropriate.

What Makes Knee Replacement Minimally Invasive?

Minimally invasive knee replacement surgery uses an approach that limits disruption to the muscles and other soft tissues surrounding the knee while allowing the surgeon to perform the fundamental steps of joint replacement. The goal is to access the damaged joint, prepare the bone, and place the replacement components while preserving as much healthy surrounding tissue as appropriate.

The implants and basic objectives of knee replacement do not fundamentally change because a minimally invasive technique is used—the surgeon still removes damaged portions of the joint and prepares the remaining bone to accommodate replacement components. What can differ is how the surgeon accesses the joint and how surrounding tissues are handled during the procedure.

The guide below gives more insight into minimally invasive knee replacement surgery and how an experienced surgeon like Dr. Shane Martin may use specialized instruments or techniques to limit tissue disruption. Nevertheless, the specific approach depends on the patient’s anatomy, the extent of joint damage, and the surgeon’s assessment.

Less Tissue Disruption Can Change the Recovery Experience

One reason surgeons may consider a minimally invasive approach is the potential to limit disruption to tissues surrounding the knee. Muscles, tendons, ligaments, and other soft tissues all contribute to the knee’s movement and stability, so preserving appropriate structures can be an important consideration during joint replacement.

When less tissue is disrupted during surgery, the early recovery experience may be different for some patients. Some examples of factors that can be influenced by how tissues are handled during the procedure are:

• How easy it is to manage pain after surgery
• How quickly swelling reduces after knee replacement surgery
• The rate at which joint mobility is restored
• The patient’s ability to begin rehabilitation

This does not mean that minimally invasive knee surgery guarantees less pain or a faster recovery. Every knee replacement involves surgical trauma, and recovery depends on factors such as the patient’s overall health, the condition of the knee, the surgical technique, pain management, activity level, and participation in rehabilitation.

Preserving appropriate soft-tissue structures can also matter as the patient works to regain strength and function. The quadriceps and other muscles surrounding the knee play important roles in standing, walking, climbing stairs, and other everyday movements. Rehabilitation therefore remains an important part of recovery regardless of whether the procedure uses a minimally invasive approach.

Precision Still Matters With a Minimally Invasive Approach

A minimally invasive approach does not eliminate the need for accurate surgical planning and execution. In some cases, limiting the surgical opening or reducing tissue disruption can make visualization and access to the joint more technically demanding—the surgeon must still have adequate access to prepare the bone and position the replacement components appropriately.

Accurate bone preparation, alignment, and implant positioning remain important parts of knee replacement. The surgeon must determine how much bone should be removed, where the replacement components should be positioned, and how those components should relate to the patient’s anatomy.

This is where technologies such as patient-specific planning and robotic assistance may provide additional information or guidance. Depending on the system being used, the surgeon may be able to create a CT-based three-dimensional model before surgery and use that information to plan bone preparation and implant positioning.

During the procedure, robotic technology can be used to improve surgical outcomes by providing guidance and measurements based on the patient’s anatomy. The surgeon remains responsible for interpreting that information and determining how to proceed.

The purpose of using technology is therefore not simply to make the surgical approach smaller. It can provide another set of tools to help the surgeon plan and execute the procedure while maintaining appropriate access to the joint.

Minimally Invasive vs. Traditional Knee Replacement

Minimally invasive and traditional knee replacement share the same fundamental goal, which is replacing damaged portions of the knee with artificial components to improve pain and function. The primary differences between minimally invasive and traditional knee replacement are how the surgeon accesses the joint and handles the surrounding tissues, as seen in the table below.

The distinction between the two approaches is not simply the size of the skin incision. A smaller incision does not automatically mean that the underlying tissues have experienced less disruption. The surgeon must balance access to the joint with appropriate preservation of surrounding structures.

Who May Be a Candidate?

Whether someone is a candidate for minimally invasive knee surgery depends on several factors. The orthopedic evaluation may consider various things about the patient, such as:

• The condition and location of arthritis or other joint damage
• Their anatomy
• Their overall health
• Whether they had previous procedures
• Their activity levels
• Their overarching goals for treatment

It is also a misconception that minimally invasive knee replacement is automatically limited to a very narrow group of exceptionally healthy or active patients. Many patients who are candidates for traditional total knee replacement may also be candidates for a minimally invasive approach. However, the appropriate technique must be determined by the surgeon after evaluating the individual patient.

Anatomy can be particularly important. A patient’s bone structure, joint deformity, previous surgery, or other anatomical considerations may affect how much access the surgeon needs during the procedure. In some cases, a different approach may provide better access or allow the surgeon to perform the replacement more appropriately.

The same principle applies to robotic assistance when systems like Mako SmartRobotics™ and the CORI surgical system are introduced. A patient should not assume that requesting a robotic or minimally invasive procedure automatically makes that approach appropriate. Instead, the surgeon can consider the patient’s specific circumstances and determine which combination of surgical technique and technology best fits the procedure.

Recovery Expectations After Minimally Invasive Knee Replacement Surgery

Minimally invasive knee surgery may help support early mobility by limiting disruption to some surrounding tissues, but patients should still expect a structured recovery process. Non-invasive knee surgery does not exist; by nature, knee surgery involves breaking the skin or entering the body, meaning the knee needs time to heal, and patients will have to work through things like:

• Pain management
• Swelling control
• Joint mobility exercises
• Strengthening
• Gradually increasing activity

The Beginning of Recovery

Early mobility is an important part of many modern knee replacement recovery protocols. Depending on the patient’s condition and the surgeon’s recommendations, this may include getting out of bed and walking shortly after surgery, often with an assistive device such as a walker for support and balance.

The first stages of recovery may focus on practical milestones such as:

• Getting up and walking safely
• Using an assistive device correctly
• Gradually improving knee range of motion
• Performing prescribed knee replacement exercises at home
• Building strength in the leg
• Progressing toward everyday activities

Recovery Can Look Different for Everyone

The recommendations given during physical therapy after a knee replacement can vary from one patient to another. Some patients may receive formal physical therapy, while others may initially follow a home exercise program based on their individual needs and the surgical team’s recommendations.

The timeline for returning to normal activities also varies. Some examples of factors that can influence recovery are:

• A patient’s age and overall health
• Strength
• Preoperative mobility
• Surgical findings
• Pain levels
• Participation in rehabilitation

For these reasons, minimally invasive knee replacement surgery should not be presented as a shortcut through recovery. The approach may influence the early recovery experience, but patients still need to follow their surgeon’s instructions and allow the knee to heal and regain strength over time, as muscle weakness is common after knee replacement surgery.

Non-Invasive Knee Surgery Alternatives

If knee pain does not yet require joint replacement, several nonsurgical or less invasive treatment options may be considered depending on the underlying cause. These approaches are generally intended to reduce pain, improve function, or delay the need for more extensive surgery when appropriate.

Non-invasive knee surgery alternative treatments may include things like:

• Physical therapy – Physical therapy can enhance long-term joint health through targeted exercises that are designed to improve strength, flexibility, balance, and the muscles that support the knee.
• Activity modification – Adjusting activities that repeatedly aggravate the knee may reduce symptoms while maintaining appropriate movement.
• Medications – Depending on the patient’s health and the cause of the pain, a healthcare provider may recommend pain medications prior to surgery to help manage symptoms.
• Injections – Certain injections may delay the need for joint replacement surgery by providing temporary symptom relief for some patients, although their effectiveness and suitability vary by condition.
• Weight management – For patients who are overweight, reducing excess body weight can decrease the mechanical load placed on the knee and may improve symptoms.
• Bracing or assistive devices – A brace, cane, or other device may provide additional support in certain circumstances.

These options are not appropriate for every type or severity of knee problem. A patient with mild or moderate symptoms may have several nonsurgical options to consider, while someone with advanced joint damage may eventually need surgical treatment.

The Right Approach Is About More Than Incision Size

When considering minimally invasive knee surgery, it can be tempting to focus on the size of the incision. However, the incision is only one part of the surgical approach—the way surrounding tissues are handled, the accuracy of bone preparation, the positioning of the implants, and the surgeon’s ability to work effectively within the joint are all important considerations.

At the Joint Replacement Center of Scottsdale, our experienced surgical team can evaluate your individual anatomy, joint condition, treatment goals, and other factors when determining an appropriate approach to knee replacement. Robotic-assisted technology and patient-specific planning may be incorporated when appropriate.

If you are considering knee replacement, contact our team to discuss your condition and whether a minimally invasive or robotic-assisted approach may be appropriate for you.