Over the past 30 years, there has been much interest in performing all types of surgery via less-invasive techniques. Many orthopaedic surgeries that used to require large, open surgical procedures can now safely be done through smaller incisions or even via arthroscopic techniques. The term "minimally-invasive" surgery or "MIS" surgery has been used and perhaps overused as a selling point for a procedure to be performed with less trauma to the patient. Such terms are often used to motivate a patient to choose one surgeon over another.
In the setting of total knee replacement, research has been done to understand whether the procedure can be done safely with "MIS" techniques. And if newer techniques are proven to be safe, do they improve either the short- or long-term outcomes for patients after surgery? The phrase "Quad-sparing total knee" has also found its way into the conversation about knee replacement surgical techniques.
Most recently, a total knee technique is being promoted that sounds like a popular type of peanut butter (we have been advised that, although it the our goal of our website is to help educate patients, we cannot use the exact name due to copyright infringement concerns- so, for practicality, we will refer to as the peanut butter and jelly or "PB & J" knee). This "new" concept is not an actual knee replacement prosthesis. It is a catchy phrase that is being used to describe a surgical technique that incorporates a "Sub-vastus" or "Southern" approach to the knee. This type of surgical technique was actually first described in 1929 and its application for knee replacement surgery was pioneered in 1991 by Dr Aaron Hofmann. (https://journals.lww.com/clinorthop/Abstract/1991/08000/Subvastus__Southern__Approach_for_Primary_Total.12.aspx)
Unfortunately, 21st-century internet and social media marketing is being used to suggest that this is a "new" surgical technique that will spare them from postoperative pain after knee replacement and shorten their recovery.
To date, the research has been inconclusive as to whether a quad sparing "MIS" TKA technique, which includes the new "PB & J" technique, is in fact better. Several studies have shown quicker recovery of range of motion, earlier ambulation and active straight leg raise ability. Yet, other studies have shown an increased risk in early post-operative complications such as wound healing complications, arthrofibrosis (knee stiffness), ligament injury or even catastrophic patellar tendon rupture.
One study evaluating a "quad-sparing" TKA technique demonstrated that 30% of patients suffered traumatic tears of the quadricep tendon during surgery that required surgical repair. Having a knee replacement via a smaller incision or "less-invasive" technique might, unfortunately, put you at risk for more complications and potentially additional surgery. To focus only on the short term recovery, rather than the long term result is, in other words, probably misguided.
When a patient is considering a potential knee replacement surgery, it is very important to recognize that there are many different variables that will influence both the short-term and long-term results of surgery. These variables include surgeon experience, surgical technique, multi-modality pain management program, use of perioperative nerve blocks and local anesthetic injections, design of the knee prosthesis, materials used to manufacture the knee prosthesis, the use of enabling technologies, specifically robotic-assisted surgery, as well as patient factors, including compliance with post-operative rehab and physical therapy rehabilitation. In other words, the surgical technique used by surgeon (MIS technique or not) is not the primary influencer of the surgical outcome.
That being said, Dr Kaper will routinely utilize the less-invasive knee replacement surgical techniques, including the "PB&J" sub-vastus approach, if it is appropriate for the individual patient and their specific anatomy and pathology. Not every patient is the same and it is only logical that there is not one simple approach that that can be used for all patients.
If you have specific questions or concerns about the techniques used to TKA surgery, please let us know. We will be happy to discuss all of these issues and concerns with you in detail.