Alternatives to knee microfracture surgery and cartilage implant surgery
Ross A. Hauser, MD. Danielle R. Steilen-Matias, MMS, PA-C.
In this article, we will present the non-surgical alternative to various surgical techniques that are designed to repair or regrow the articular cartilage of the knee.
As we will see in the research below, many people do very well with microfracture knee surgery or arthroscopic abrasion arthroplasty procedures. If you have been recommended to one of these procedures you probably do not need a detailed explanation as to what these procedures do. In these procedures there is drilling or scrapping into the bone beneath or behind the cartilage with the hope that healing elements from the blood released from the bone drilling will help stimulate the repair of cartilage.
The people who do well with these procedures are usually not the people we see in our clinics. We see the people who have had the procedure fail on them, sometimes not once, but two or three times. Some of these people’s stories go something like this:
I’ve had multiple microfracture failures.
I’ve had multiple microfracture failures. I was then recommended to an ACI (autologous chondrocyte implant. In this procedure a small sample of good cartilage is taken from one part of the knee and used to patch a hole in another part of the knee), this surgery also failed. I am now being told to consider total knee replacement as soon as I get a little older. For now, I have been told to stop my favorite activities, do as little weight-bearing activity as possible, and live on pain pills.
If you are reading this article it is likely that you too have had multiple procedures that have either failed or “worn out.” ACI or autologous chondrocyte implants are designed to delay the need for knee replacement, not substitute for it.
Knee articular cartilage surgery: “the limited repairing capacity and the potential pitfalls of these techniques cannot be ignored.”
A September 2019 study in the journal Therapeutic Advances in Musculoskeletal Disease (1) comes from researchers who gave this assessment of some of the surgical procedures they employ:
“Surgical intervention to repair cartilage may prevent progressive joint degeneration. A series of surgical techniques, including biological augmentation, microfracture and bone marrow stimulation, autologous chondrocyte implantation (ACI), and allogenic and autogenic chondral/osteochondral transplantation, have been used for various indications. However, the limited repairing capacity and the potential pitfalls of these techniques cannot be ignored.”
In researching such surgical options as:
- Microfracture knee surgery or Arthroscopic microfracture drilling:
- If you have cartilage breakdown behind the kneecap or in the knee joint itself, this procedure may be recommended to stimulate healing by drilling into the bones of the knee underneath the cartilage. The hope is that the drilling will cause bleeding, the blood will clot and the clotted blood with serve as a scaffold for new cartilage cells to develop and patch the holes in your existing cartilage.
- Arthroscopic abrasion arthroplasty
- This surgery is best recommended to a younger athlete who has a simple cartilage tear or hole. It will usually not be successful for a patient who is older or a patient who has a significantly damaged knee. In this procedure as opposed to drilling holes in the bone, burrs are used to scrape away damaged cartilage and “scrape” the bone. As with the microfracture procedure, the hope is to cause the blood to clot and turn into a scaffold from which cartilage cells can develop.
- Autologous Chondrocyte Implantation (ACI)
- This is a newer procedure. It requires two surgical procedures. The first is an arthroscopic procedure which takes a small piece of articular cartilage from the patient’s knee to separate out chondrocytes (cartilage building cells). These cells are then multiplied or expanded in numbers in the lab. In most cases, six to eight weeks later, in the second procedure, the more numerous cells are replanted into the cartilage defect.
- Osteochondral Autograft Transplantation (Donor cartilage from you)
- Osteochondral Allograft Transplantation (Donor cartilage from a cadaver)
We often find one of the successes of the surgery outcome in these procedures is that the patient did not need multiple surgeries and that these procedures put off the eventual need for knee replacement.
In December 2022 doctors at the University of Missouri-Kansas City, Galway University Hospitals, Galway, Ireland and the National University of Ireland Galway addressed this problem in the journal Bone (19) “Issues with current treatments for osteochondral defects such as mosaicplasty and autologous chondrocyte implantation (ACI) are lack of donor material, problems associated with donor sites, necessity of second surgical intervention and cell expansion, difficult site preparation and implant fitting to match the surrounding tissue.” To help solve these problems, the researchers put forth the development of a patient specific implant system for focal osteochondral defects that addresses these issues that is now being studied.
Mosaicplasty surgery transplants bone and cartilage from non-weight bearing areas of the knee to damaged areas of the knee.
In May 2022 doctors at the orthopaedics surgery and sports medicine department, FIFA Medical Centre of Excellence, Croix-Rousse hospital, Lyon university hospital offered a comparison between open mosaicplasty and arthroscopic mosaicplasty. They published their findings in the journal Orthopaedics & traumatology, surgery & research. (21) Clinical outcomes were good with both techniques. The proportion of patients with excellent (pain and functional) scores was significantly higher in the arthroscopy group than in the arthrotomy (open exploration surgery) group. This result may be ascribable to decreased donor-site morbidity (infection or other side-effects) . . . (typical of) arthroscopy.”
A March 2022 study in the journal Arthroscopy techniques (22) addressed the concern regarding osteochondral autograft transfer of donor-site morbidity of the knee, the most common source of the autograft. The concern is infection or other problems created by removing cartilage and bone from one side of the knee to the other. In this paper researchers explored taking the cartilage and bone from the iliac crest (the upper pelvis where bone marrow is usually taken from for stem cell treatments). The researchers suggest taking a “plug” covered by a same-sized cylinder of hyaluronic acid-based polymer scaffold pretreated with bone marrow aspirate concentrate.
What are we seeing in this image?
In this image, we can see the hole created by the missing cartilage. In this particular image, the impact of cortisone or steroid injections can be illustrated. A patient like this may be recommended to knee microfracture surgery and cartilage implant surgery.
Microfracture surgery for articular cartilage repair
“Currently, there is no effective non-surgical treatment for articular cartilage injury. . . functional recovery is not satisfactory”
In November 2017 doctors from the Institute of Orthopaedics in China wrote in the medical journal Trials, (2) “Spontaneous recovery from articular cartilage injury is difficult, and the ongoing progression of the disease can eventually lead to osteoarthritis. Currently, there is no effective non-surgical treatment for articular cartilage injury. Arthroscopic debridement and microfracture surgery are performed for fibrocartilage repair. But fibrocartilage is different from normal articular cartilage, and functional recovery is not satisfactory.”
This research was not as enthusiastic as earlier 2017 studies where surgical researchers were happy to announce that cartilage repair or regeneration procedures (e.g., microfracture, Autologous Chondrocyte Implantation – ACI) typically result in a satisfactory outcome in selected patients.
This was also detailed in a 2016 (3) paper by doctors at the University of New Mexico who published research in which they suggest success in selective patients undergoing knee procedures including chondroplasty, debridement, drilling, microfracture autologous chondrocyte implantation, osteochondral autograft, and osteochondral allograft, and that while these techniques may improve patient outcomes, NONE can reproduce normal hyaline cartilage.
Below I will discuss with you the application of Mesenchymal stem cells or sometimes referred to a Mesenchymal stromal cells in treating patients with cartilage defects. Briefly I want to point out this research in response to the problems mentioned above and how stem cells may help.
In response, researchers in 2022 wrote in the International journal of molecular sciences (20) about adding Mesenchymal stromal cells (stem cells) to these procedures. “Healing of articular cartilage defects presents a challenging issue, due to its regenerative shortcomings. Lacking vascularity (blood supply) and innervation of cartilage and low proliferative potential of chondrocytes are the main reasons for the limited healing potential of articular cartilage. Traditional reparative approaches are limited in their efficiency. . . Mesenchymal stromal cells, preferred for clinical uses, can be readily derived from various sources and have been proven to have a therapeutic effect on cartilage and subchondral bone.”
At our center, we use a person’s own Mesenchymal stromal cells (stem cells) from bone marrow or adipose (fat). These cells are concentrated or directly injected into the knee. We also add dextrose (Prolotherapy injections) or platelet injections (from the patient’s own blood) to all of the supportive joint structures for a more thorough treatment. Our non-surgical goals are the same goals as the surgical procedures: stimulate the repair of cartilage defects. Stem cells aid in fibroblastic proliferation (connective tissue that creates collagen, a cartilage building block). Again, these treatments are discussed below and in greater detail.
When microfracture is most successful for rebuilding cartilage and when it is not
In February 2020, surgeons at the University Hospital, LMU Munich published these findings in the journal Knee Surgery, Sports Traumatology, Arthroscopy: (4)
“Third-generation autologous chondrocyte implantation (ACI) is an established and frequently used method and successful method for the treatment of full-thickness cartilage defects in the knee. There is also an increasing number of patients with autologous chondrocyte implantation as a second-line therapy that is used after failed bone marrow stimulation in the patient’s history. . . In this study, the clinical results after the matrix-based autologous chondrocyte implantation in the knee in a follow-up over 3 years postoperatively were analyzed. This study showed that third-generation autologous chondrocyte implantation is a suitable method for the treatment of full-thickness cartilage defects. However . . .autologous chondrocyte implantation after failed bone marrow stimulation leads to worse clinical results.”
This is the problem, the cartilage repair is not as durable as the native cartilage. It is not a long-term solution.
- A team of international researchers writing in the medical journal Tissue Engineering agreed in their research stating that the vast majority of patients with chronic symptoms and, in general, a more diseased joint, do not benefit from these surgical techniques. (5)
In March 2017, Rush University Medical Center researchers suggested in the journal Sports Medicine and Arthroscopy Review:
- “For the vast majority of patients, marrow stimulation results in reduced pain and improved function, providing overall satisfactory outcomes. In some cases, however, marrow stimulation fails, resulting in symptom recurrence and often, the need for repeat surgery.”(6)
And in January 2017 research from Rush and Duke Universities about youth athletes:
- “Autologous Chondrocyte Implantation is an effective treatment for adolescent patients with symptomatic, large chondral lesions, resulting in significant improvements in knee-specific functional outcome scores and health-related quality of life scores.
- Although patients must be cautioned on the relatively high reoperation rate (37.8%) and limitations in knee function even after ACI“(7)
Good results with autologous chondrocyte transplantation
An October 2022 study from German surgeons published in the Archives of orthopaedic and trauma surgery (23) investigated postoperative complications and associated risk factors for failure following autologous chondrocyte transplantation as well as its long-term survival and clinical function. The researchers found ACT as an effective treatment option for femorotibial- as well as patellofemoral cartilage defects with a high long-term survival and low conversion rate as well as good long-term results regarding knee function and satisfaction.
Postoperative complications needing revision surgery are rare. Prolongated deficits of range of motion appear frequently up to six months especially in patellofemoral defects, but can often be successfully addressed by intensified physiotherapy without requiring an arthrolysis. Postoperatively, 8% of patients had complications (4% bleeding, 2% arthrofibrosis, 2% infection), 7% of patients needed revision surgery. 12% of patients had a prolonged deficit in ROM, that did not require revision surgery.
Good candidates for surgery, bad candidates for surgery
In February 2018 published in the Orthopaedic Journal of Sports Medicine,(8) doctors at Keck School of Medicine, the University of Southern California, and the Department of Orthopedic Surgery, Rush University Medical Center offered these findings on which patients Microfracture would offer the most benefit stating that “Microfracture has become a common treatment option for relatively small, symptomatic cartilage defects in the knee.”
- Patients who underwent microfracture showed clinically meaningful and statistically significant improvements in patient report outcomes after an average of 5.7 years, regardless of whether it was performed at a single site tear, multiple site tear, or with concomitant procedures.
- Overall, male patients demonstrated better final postoperative patient report outcomes as well as a greater magnitude of improvement when compared with their female counterparts.
Patients who did not have a more desired response to surgery and were less than good candidates.
- Older age,
- Higher BMI Body Mass Index (weight/obesity)
- Larger defect size in the cartilage
- If the knee had multiple defect locations
- If you had a larger lesion/tear size and prior surgery predicted the need for additional surgery after microfracture.
The researchers also noted that the surgery worked best when the cartilage tear was small and was the only tear. A wound in isolation. They note that this type of patient while ideal is rarer than the true to life patient who has many concomitant challenges such as meniscus damage, loose bodies in the knee, synovial inflammation of the knee requiring Synovectomy or cleaning out of the inflamed synovial tissue. Additionally, some of the study subjects had the procedure done at the time of Anterior cruciate ligament reconstruction or Medial patellofemoral ligament reconstruction.
At our clinics, we rarely see a patient that has a small cartilage tear in isolation. When we do we find very high success rates with our regenerative medicine injections. Patients who have a more advanced knee injury or advanced levels of degeneration would obviously require a more comprehensive approach to healing.
“osteochondral allograft in the knee remains an inapplicable option in the treatment of post-traumatic end-stage arthritis of the young patient”
Doctors at Italy’s Bologna University looked at osteochondral allografts (cartilage transplantation from a donor) for their treatment of end-stage arthritis in younger post-traumatic arthritis patients. Here are their troubling findings:
- Bipolar fresh osteochondral allografts (Cartilage transplant) recently became a fascinating option for articular cartilage replacement, in particular in those young patients non-suitable for traditional replacement because of age.
- HOWEVER Bipolar fresh osteochondral allograft in the knee remains an inapplicable option in the treatment of post-traumatic end-stage arthritis of the young patient, due to the high rate of failure. (9)
The need for success options is obvious. Doctors at the University of Alberta and the University of Calgary in Canada (10) found that young athletes with post-traumatic knee arthritis had significant and rapid physical declines between the time of injury and the onset of arthritis.
In this study the Canadian researchers looked at:
- Patients in the age range of 15-26.
- Fifty with a sport-related intra-articular knee injury sustained 3-10 years previously and 50 uninjured age, sex, and sport matched controls.
- Injured participants demonstrated poorer KOOS outcomes. KOOS is The Knee injury and Osteoarthritis Outcome Score based on what the patient reports in their pain, function, quality of life, and sport/recreation participation.
- Many patients became overweight/obese following their knee injury.
The study’s authors reiterated in their conclusion: “This study provides preliminary evidence that youth/young adults following sport-related knee injury report more symptoms and poorer function, and are at greater risk of being overweight/obese 3-10 years post-injury compared to matched uninjured controls.”
Curious and troubling findings in patients who previously had Microfracture surgery and then went on to total knee replacement
Researchers writing in the medical journal Orthopedics found curious and troubling findings in patients who previous Microfracture surgery and then went on to total knee replacement. In comparing total knee replacement patients who had the Microfracture surgery and those who did not prior getting a knee replacement, the doctors found that
- Patients who had Microfracture surgery prior to knee replacement demonstrated significantly less improvement in knee pain and function than the patients who did not have prior microfracture
- The knee replacement failure rate after five years was doubled: 4.8% to 2.4%.
- Older patients had less clinical improvement than hoped for
- Patients with a less preoperative range of motion after Microfracture had less clinical improvement than hoped for
- Women with an increased body mass index also had less improvement. (11)
Surgery creates more bone damage
Doctors at Saarland University Medical Center in Homburg, Germany publishing in the journal Scientific Reports (12) tested the hypothesis that early osteochondral repair following microfracture surgery is enhanced if bone marrow stem cell aspirate is added as an adjunct to the microfracture procedure.
The problem they were trying to solve was that the surgery creates more bone damage.
- Their key finding is that microfracture treatment of chondral defects induced a substantial early loss of the subchondral bone that may be significantly counteracted if bone marrow aspirate is applied.
- Second, such bone marrow aspirate enhanced microfracture also significantly protected the subarticular spongiosa (the spongy) below the defects from osteoclast-mediated peri-hole bone resorption (over reabsorption of bone) compared with microfracture alone.
Interestingly, debridement down to the subchondral bone similarly led to a reduction of the bone volume both in the subchondral bone plate and subarticular spongiosa.
Surgeons adding bone marrow-derived stem cells to surgery and post-surgical care
Surgeons now consider adding bone marrow-derived stem cells to surgery.
Here in our opinion is another example of overcomplicating a simple procedure, the introduction of reparative stem cells into the knee.
- Here is the more complicated surgical process:
- Researchers wanted to know if they could regenerate articular cartilage in patients with severe cartilage deterioration by drilling the bone underneath the cartilage (to jump-start healing) and then after the surgery if intra-articular injections of hyaluronic acid with and without peripheral blood stem cells (PBSC) repaired the tissue.
- The doctors took 50 patients (young patients age 18 to 50) with cartilage loss and began to drill the bones. One week after the drilling, 25 of the patients received a weekly injection of hyaluronic acid (HA) with peripheral blood stem cells, 25 without. Then 6 months later the injections were repeated.
- The researchers found that arthroscopic subchondral drilling (drilling underneath the cartilage) into grade 3 and 4 chondral lesions, postoperative intra-articular injections of (stem cells) in combination with hyaluronic acid resulted in an improvement of the quality of articular cartilage repair over the same treatment without (stem cells). In other words, when the stem cells were added, everything worked better. (13)
So here is the understanding of it all:
1. Arthroscopic drilling
2. hyaluronic acid injections
3, stem cells therapy
and more injections six months later.
The study focused on the surgery and what made the surgery work better, and it wasn’t hyaluronic acid. It was the stem cells.
Why not try the repair with bone marrow aspirate stem cells without the surgery first?
In another study doctors writing in the medical journal Arthroscopy (14) found that in 55 knees that underwent High Tibial Osteotomy (bone resurfacing or reshaping) and microfracture, those who received stem cells with hyaluronic acid had significantly better results than those who just received hyaluronic acid.
- Research in the medical journal Cartilage showed that a “one-step” surgery bone marrow aspirate stem cell treatment showed good results in helping stage IV knee osteoarthritis patients Back to the original question, why not try the repair without the surgery FIRST when research suggests stem cells have the ability to repair and reshape the bone. (15)
Other research including Caring Medical published findings
- Other research, including our own, shows complete relief of symptoms in arthritic joints with bone marrow stem cell treatments. (16) Below we will discuss three case studies from this research.
Here is a recent study that can suggest that trying the stem cell injections first may be a more realistic option for patients especially those concerned with microfracture knee surgery recovery time and rehab.
Abrasion Arthroplasty is a procedure that sounds exactly what it is – abrasions are created on the cartilage to create an injury with the hope that the body will repair not only the new injury but the deterioration of the joint as well. This is a surgical procedure. Studies have pointed out that this procedure may help alleviate symptoms of knee pain but it is not curative. (17)
Not only non-curative – may not work at all.
Doctors at RWTH Aachen University in Germany had a problem with Arthroscopic abrasion arthroplasty. They are not sure it worked at all. To test the theory that the surgery was helpful – they examined the effusion, the swelling fluids in the knee following the surgery.
What they found was the surgery indeed starting a healing process by stimulating STEM CELLS to repair the cartilage.
Now here is the amazing part. The doctors found that during the surgery, the doctors used constant suction to drain the surgical area. The researchers now “recommend not to use suction drainage as by this procedure a considerable amount of the regenerative potential of postoperative joint effusions might be extracted.”(18)
- In other words, the stem cells were stimulated to repair spontaneously and mobiles to the wound site.
- The benefit to the surgery was to get stem cells to the wound
- The surgery’s benefit was being removed as soon as it started.
Treatment for articular cartilage is challenging because knee cartilage shows limited reparative and regeneration abilities following injury. Traditional non-operative (RICE therapy), various injection therapies, and traditional arthroscopic techniques cannot restore the normal anatomy and function of cartilage in osteoarthritis.
Stem cell therapy for cartilage repair need not be a complicated procedure. In many instances, bone marrow stem cells are drawn from a patient and injected into the patient’s knee with the hope of repairing cartilage and bone damage typical of a knee with severe osteoarthritis or damage from injury. The procedure is simple in concept: inject stem cells, heal the knee. Please watch the video below.
Caring Medical Research
Please see our discussions in the medical journal Clinical Medicine Insights. Arthritis and musculoskeletal disorders where our team presented three difficult knee pain case histories treated with Bone Marrow Stem Cell Aspirate. In this article, we will present clinical research and case studies to support the use of Bone Marrow Aspirate for Knee Pain. Bone Marrow Aspirate therapy is often called bone marrow stem cell therapy or simply stem cell therapy.
We do not offer stem cell therapy or bone marrow aspirate therapy to every patient. If the patient is a good candidate, we may suggest simpler dextrose Prolotherapy treatments.
- Prolotherapy is a simple regenerative medicine injection treatment.
- Injections of dextrose, a simple sugar, are given into the knee to stimulate the immune response to repair damaged, loose weakened ligaments bringing stability to the knee which addressing the problems of holes in cartilage.
In this video, Danielle R. Steilen-Matias, MMS, PA-C, of Caring Medical demonstrates how we treat a patient with a primary complaint of knee osteoarthritis.
- The person in this video is being treated for knee osteoarthritis as the primary complaint. The treatment takes a few minutes. The person in this video is not sedated and tolerates the treatment very well. For some patients, we do provide IV or oral medications to lessen treatment anxiety and pain.
- The first injection is given to the knee joint. The Prolotherapy solution is given here to stimulate repair of the knee cartilage, meniscal tissue, and the ACL as well.
- The injections continue over the medial joint line making sure that all the tendons and ligaments such as the medial collateral ligament are treated.
- This patient-reported more pain along the medial joint line. This is why a greater concentration of injections is given here.
- The injections continue on the lateral side of the knee, treating the lateral joint line all the tendon and ligament attachments there such as the LCL or lateral collateral ligament.
PRP and Prolotherapy
- PRP treatment takes your blood, like going for a blood test, and re-introduces the concentrated blood platelets from your blood into areas of chronic joint and spine deterioration.
- Your blood platelets contain growth and healing factors. When concentrated through simple centrifuging, your blood plasma becomes “rich” in healing factors, thus the name Platelet RICH plasma.
- The procedure and preparation of therapeutic doses of growth factors consist of an autologous blood collection (blood from the patient), plasma separation (blood is centrifuged), and application of the plasma rich in growth factors (injecting the plasma into the area.) In our office, patients are generally seen every 4-6 weeks. Typically three to six visits are necessary per area.
Do you have a question about Knee articular cartilage surgery or becoming a patient? Get help and information from our Caring Medical staff
References for this article
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