New Quad Sparing Technique May Provide Faster Recovery for Patients with Arthritis of the Knee
Minimally-invasive quadriceps-sparing total knee replacement is a new surgical technique that allows surgeons to insert the same time-tested reliable knee replacement implants through a shorter incision using surgical approach that avoids trauma to the quadriceps muscle (see figure 1) which is the most important muscle group around the knee. This new technique which is sometimes called quadriceps-sparing knee replacement uses an incision that is typically only 3-4” in length (see figure 2) and the recovery time is much quicker – often permitting patients to walk with a cane within a couple of weeks of surgery or even earlier. The less-traumatic nature of the surgical approach also may decrease post-operative pain and diminish the need for rehab and therapy compared to more traditional approaches.
The main potential benefits of this new technique include:
- More rapid return of knee function. Patients who undergo this procedure seem to get muscle strength and control back more quickly than patients who have had traditional total knee replacement. (See Video) This is because the quadriceps muscle and tendon are not divided in the course of the surgical exposure like in traditional knee replacement and the kneecap is not everted (flipped out of the way) as it is in traditional total knee replacement.
- Smaller incision. While this procedure would not be worth performing for cosmetic benefits many patients do prefer the shorter incision. Traditional knee replacement incisions often measure 8” or longer; minimally-invasive quadriceps-sparing knee replacement incisions are about 4” in length for most patients.
- Decreased post-operative pain. (See Video)This may be a function of the smaller incision and the fact that the incision stays out of the important quadriceps muscle/tendon group.
- Same reliable surgical implants as Traditional Knee Replacement. Much has been learned about implant design in the nearly 40-year history of contemporary knee replacement. Minimally-invasive quadriceps-sparing total knee replacement is an evolution of surgical technique which permits the use of time-tested implant designs (see figures 3 and 4). This gives some reassurance that while the surgical approach is new the implants themselves have a good proven track record.
The major apparent risks of the procedure compared to traditional total knee replacement:
- The procedure is new. Though surgeons have studied the approach the studies are recent and have replicated (repeated and verified) by only a few groups of surgeon-scientists. These studies give some insight into which patients and patterns of arthritis are most suitable for this procedure the relative novelty of the approach it is likely that as time passes we will discover more about the risks and shortcomings of this technique. Also even an experienced knee replacement surgeon will have performed many more surgeries through the traditional approach than through the less-invasive method; we know that the more procedures one does the more reliable the results are.
- The procedure is more challenging. Operating through a smaller surgical window takes some getting used to and this can increase operative time compared to procedures performed using the traditional technique. This may increase the likelihood that an intra-operative injury to tendon or ligament might occur which could compromise the result. This may also increase the likelihood of component malalignments which could affect function and durability. However two preliminary studies on this technique in fact found that these adverse outcomes did not take place.