Platelet rich plasma injections for meniscus tears
Ross Hauser, MD, Danielle R. Steilen-Matias, MMS, PA-C
Platelet rich plasma injections for meniscus tears
In this article, we will explore research on Platelet Rich Plasma therapy for meniscus injury. This article is for people exploring the possibility of:
- Meniscus arthroscopic surgery.
- Meniscus arthroscopic surgery with PRP augmentation.
- PRP injection treatment for meniscus tears as a non-surgical option.
- Post-surgical treatment help.
Patients will contact our office with questions about their meniscus injury and ask what our recommendations are for treatment. Of course, the best recommendations are made after we perform a physical examination and check for range of motion, popping and clicking sounds, and catching and other issues of knee instability where the meniscus may be considered a culprit.
The patient may already have an MRI showing a meniscus tear, a recommendation for arthroscopic meniscus surgery, or a history of physical therapy and other conservative care treatments including anti-inflammatories and/or a recommendation from a surgeon that they really need to wait until their knee is worse before an operation can be performed.
One of the treatment options the patient may have researched is platelet rich plasma therapy or commonly referred to as PRP. PRP is an injection treatment that re-introduces your own concentrated blood platelets into areas of chronic joint deterioration.
Many questions about the “White Zone Tear”
Many people will email our office and will make a clear distinction about the type of tear they have by using the designation “red zone tear,” or “white zone tear.” More people will say they have a “white zone tear.” Why? Because they have been given the explanation that white zone tears are very difficult to treat and that these tears usually require surgery to cut out the damaged area of the meniscus.
Emails of this nature go something like this:
- I have a ruptured medial meniscus. It is all in the white zone. MRI says horizontal-diagonal complex tear. Currently getting physical therapy and doing the recommended exercising every day. I still have a lot of knee pain. My orthopedist said, that it is not possible to repair or regenerate (with PRP injections see below) the white part of the meniscus.) We will answer this below.
- I have a lot of problems with my knee, I have a Baker’s Cyst that comes and goes that causes a lot of problems. I also have a torn meniscus that I did not know I had. My doctor says my meniscus problem is not good because it is in the white zone and I should have surgery. At this point, the surgery is knee replacement and I can get cortisone injections until I can get a knee replacement.
- I have a white zone meniscus tear. I have to use a knee brace to get around. I have difficulty with stairs. Cortisone and hyaluronic acid treatments are no longer effective. I have been researching PRP injections online. I noticed you talk about a more comprehensive strategy. The doctors I have reached out to seem to suggest a single visit or single treatment method and if that does not work, then I should just move onto surgery.
We discuss below why PRP is not a “one-shot wonder treatment,” and should not be thought of in this way. This helps prevent an over-expectation of what one treatment can do and presents a more realistic treatment path to the patient.
Menisci have two zones. The red zone is outside and the white zone is inside. Meniscus tears are characterized by their placement within these two zones.
A red zone tear lies within the blood-rich portion of the meniscus. Where there is a blood supply there is healing as blood brings the healing and growth factors needed for wound repair.
- The white zone meniscal tear is thought to be non-healing because there is no direct blood supply.
- Many doctors do not believe the white zone meniscus tear can be repaired because of this.
- This is typically the part of the meniscus removed in meniscus surgery.
In the research below we will show that when you address the problems of the whole knee, Baker’s cysts, ligament laxity and damage, cartilage deterioration, patella problems, nephropathy, you can address problems of the white zone meniscus tear without surgery.
A brief explanation of PRP treatment by Danielle R. Steilen-Matias, MMS, PA-C
- One of the most common medical conditions we see at Caring Medical is Meniscal tears.
- We treat patients with Prolotherapy and PRP injections.
- We inject the PRP into the meniscus tears with ultrasound guidance and then use the dextrose Prolotherapy to treat and strengthen the supportive ligaments of the knee to provide the knee with improved stability. We find that our meniscus tear treatment success rate is greatly helped by focusing on and treating the MCL ligament. Using ultrasound we will examine the integrity of the MCL.
- Typically a meniscus tear would require 4 – 6 treatments depending on the tear and activity or work demands of the patient.
“I am just doing my research”
When we talk to patients with a meniscus injury, they have already been well conditioned that surgery is their ultimate fate. Why?
- Lack of improvement after many physical therapy sessions
- Continued pain left the person with “no options.”
Now if you are reading this article, we understand that you are doing your research. You are looking for other options. Why?
- You do not want a surgery
- You are concerned about recovery time
- You are concerned about the rapid advancement of osteoarthritis and ultimately a need for knee replacement if your meniscus is removed. You are not the only one with this concern, please see our article Should I have knee surgery for a meniscus tear? for research shared by surgeons with their concerns.
How we utilize PRP to repair your knee. The difference between INJECTION vs. INJECTIONS
Before we get into the research of PRP for Meniscus injury we want to demonstrate, in the videos below how we offer PRP injections. You will notice that the treatment is injections, not AN injection.
In this video, Ross Hauser, MD explains how one injection of PRP will likely not work
We will often get emails from people who had previous PRP therapy without the desired healing effects. We explain to these people that their treatment probably did not work because the single PRP injection did not resolve knee instability. The PRP may have tried to create a patch in the meniscus but the instability and the wear and tear grinding that tears at the meniscus remained.
When a person has a ligament injury or instability, the knee becomes hypermobile causing degenerative wear and tear on the meniscus and knee cartilage. In other words, the cells of the meniscus and cartilage are being crushed to death. When you inject PRP into the knee, without addressing the knee instability, (treating the ligaments,) the injected PRP cells will also be subjected to the crushing hypermobile action of the knee. The single injection PRP treatment will not work. The knee instability needs to be addressed with comprehensive Prolotherapy around the joint.
Why do we give injections and not a single shot?
In the many emails we get from people looking for information on his/her meniscus tear, we often hear of their meniscus injury, and then we hear about the other structures of the knee that have been damaged. Sometimes we hear about this other damage almost as an afterthought. For instance:
- “I am scheduled to have meniscus surgery . . . and I have a Baker’s Cyst”
- “I am scheduled to have meniscus surgery . . . and yes I had an ACL reconstruction a few years ago”
- “I am scheduled to have meniscus surgery . . . and yes I had a meniscus surgery before, I think for the medial meniscus, this time it is the lateral meniscus.”
A meniscus injury is usually not an isolated injury
- If the injury is from an impact injury, there is typically enough force to damage or stretch the supporting knee ligaments including the ACL, PCL, and MCL even if an MRI shows “no damage.”
- If the meniscus tear is from degenerative wear and tear and overuse, the meniscus needs to be treated as A PART of degenerative knee disease. The meniscus cannot be fixed in isolation, the entire knee environment must be addressed to remove pressure from the meniscus and help the meniscus repair.
This PRP treatment addresses the ligament instability of a loose knee
The reason patients are seeking out alternatives to conservative care or surgical intervention for meniscus injury is that these treatments have come under intense scrutiny in the medical community for failing to help patients achieve long-term knee repair. The most serious of the long-term consequences is an acceleration of joint degeneration.
- In brief, in the research, surgeons warn each other that they face the difficult decision of removing or retaining the meniscus during an arthroscopic procedure. If the decision is made to retain the meniscus, the surgeons must address the difficulties of post-operative meniscal healing.
One option is to introduce Platelet Rich Plasma into the surgery. For some of our patients, this is in fact where they heard about PRP the first time, when a doctor discussed with them surgical possibilities and the use of PRP for accelerated surgical healing.
PRP for meniscus repair, best during surgery or in-office injection?
Often a patient will come in for a consultation asking about PRP treatments during an arthroscopic procedure. Why would surgeons be eager to use PRP during the time of surgery? A team of Polish medical researchers helped answer this question in the journal BioMed Research International. (1) These are the learning points:
- “Meniscus healing has always been a major challenge for orthopedic surgeons. All types of meniscectomies can lead to an increase in the risk of osteoarthritis. “
- “Clinical studies comparing total and partial meniscectomy have documented the beneficial effects of meniscus preservation (not removing the meniscus tissue). However only limited data exist and it so far fails to unequivocally support the benefits of meniscal repair over the partial meniscectomy.”
- Note: The surgical repair procedure to stitch up a torn meniscus does not show more benefit than partial meniscectomy.
- Although the reoperation rate for partial meniscectomy is significantly lower than for the meniscal repair (3% versus 20%), recent studies provided some evidence concerning the benefits of the latter. In the long-term follow-up (10 year) 78% of the patients who underwent the meniscal repair have no radiologic signs of osteoarthritis versus only 63% in the partial meniscectomy group. So, the current practice is to preserve meniscus tissue, with minimal resection.
The most important finding of this study is that PRP augmentation improved the healing rate of complete vertical meniscus tears located in the red-white zone. Additionally, the functional outcomes at 42 months were better in patients treated with PRP-augmented meniscus repair than in those treated with only meniscus repair; however, pain levels were comparable between these patient groups.
What does all this mean to the patient who is exploring treatment for a meniscus tear, especially a tear that extends from the blood-rich meniscus to the blood-deprived meniscus white-zone?
- It is better not to remove meniscus tissue
- Treating with PRP at the time of surgery helped
- BUT – this is the BIG BUT – “the functional outcomes at 42 months were better in patients treated with PRP-augmented meniscus repair (at the time of surgery) than in those treated with only meniscus repair; however, pain levels were comparable between these patient groups.” Why the pain? Because the treatment isolated on the meniscus and not the whole knee capsule as PRP injections do.
Continue reading the evidence for injection treatment is below.
Doctors at the Department of Orthopaedics, Xiangya Hospital, Central South University in China published their research in the journal Medical Science Monitor. (2)
In this research, they discuss the meniscus white-white tears which they describe as “a meniscus lesion completely in the avascular zone (white zone) are without blood supply and theoretically cannot heal.”
They hypothesize that doctors need to get blood to this meniscal zone for healing to occur but face the task that the problem of promoting meniscal healing in the avascular area has not yet been resolved. The possible answer? Platelet-rich plasma (PRP). The Chinese team supports the idea that the application of platelet-rich plasma for white-white meniscal tears will be a simple and novel technique of high utility in knee surgery.
Platelet-rich plasma (PRP) can be the answer for some surgical patients during the surgery to address the healing challenges of the “white-on-white” meniscus tear.
So the idea is to bring PRP in during the surgery, apply it to areas where normal blood supply is limited and this should accelerate healing. In theory, should work great. But it does not.
Meniscus arthroscopic surgery with PRP augmentation
Meniscal Surgery: a poor option that PRP intervention at the time of surgery may or may not help
There is no question that cartilage heals slowly and poorly this includes the meniscus. Recommendations for surgeries involving shaving or removing the torn portion of the tear using arthroscopic surgery, or sewing the tear together is flawed because it does not repair the deteriorated meniscus.
By failing to heal the damaged meniscal cartilage, surgery does not alleviate the chronic pain that people with this condition experience.
Here is research from the University of Virginia Health System. Here doctors focused on the problem of increased contact stresses in the knee after meniscectomy. (3)
They note that since Platelet-rich plasma has received attention as a promising strategy to help induce healing, the doctors then sought to:
- evaluate whether PRP augmentation at the time of (surgical) meniscal repair decreases the likelihood that subsequent meniscectomy will be performed; in other words, could PRP prevent the need for a second meniscus surgery.
- determine if PRP augmentation in arthroscopic meniscus repair influenced functional outcome measures; and
- examine whether PRP augmentation altered clinical and patient-reported outcomes.
In this study, the experiment was to remove meniscus tissue and see if PRP treatment made a significant impact on the surgical outcome. Before we go on, a quick citation is needed to help with the understanding of the dilution of PRP during surgery.
- University of South Alabama College of Medicine published in the Journal of Surgical Orthopaedic advances a troubling study with implications for healing after arthroscopic surgery. These researchers hypothesized that agents injected into the knee during and after knee arthroscopy will be significantly diluted by residual arthroscopic fluid by 27%. (4)
So theoretically, during surgery, a weakened PRP treatment is asked to heal the surgical and meniscal damage
Returning to the University of Virginia Health System research, its conclusion should then not be surprising:
“Patients who sustain meniscus injuries should be counseled at the time of injury about the outcomes after meniscus repair. With our limited study group, outcomes after meniscus repair with and without PRP appear similar in terms of reoperation rate.”
In the two above studies, researchers sought to improve the surgical outcomes in meniscal surgery by applying a PRP solution to the torn meniscus during the procedure. PRP could not be confirmed as effective – the culprit for non-conclusive results was not the PRP but the surgical procedure.
Let’s wrap up this section by reviewing the February 2019 research from the same Polish researchers we cited earlier. This time published in the International Journal of Molecular Sciences. (5)
Here are the learning points:
- In cases of Meniscal tears, no benefit with surgical treatment is observed.
- The purpose of this study was to investigate the effectiveness and safety of platelet rich plasma application to complement the repair of a chronic meniscal lesion.
- The repair was a meniscal trephination with or without concomitant PRP injection.
- In this procedure, a hole is drilled through the meniscus tissue to allow blood to flood the damaged area.
- This double-blind, placebo-controlled study included 72 patients. All subjects underwent meniscal trephination with or without concomitant PRP injection.
- Meniscal non-union (the failure of the meniscus to regenerate and repair) observed in magnetic resonance arthrography or arthroscopy were considered as failures.
- The failure rate was significantly higher in the control group (70% failure) than in the PRP augmented group (48% failure).
- There was a significant reduction in the number of (second) performed arthroscopies in the PRP augmented group.
- A notably higher percentage of patients treated with PRP achieved minimal clinically significant difference in pain scores.
- The conclusion of the study indicates that percutaneous meniscal trephination augmented with PRP results in a significant improvement in the rate of chronic meniscal tear healing and this procedure decreases the necessity for arthroscopy in the future (8% vs. 28%).
There is still a high failure rate.
Medical reviews of PRP meniscus injections without surgery
Research has shown that the damaged meniscus lacks growth factors to heal. Research has found that injections of PRP bring the healing components to the site of the injury.
These components are:
- platelet-derived growth factor (PDGF), (the components of Platelet Rich Plasma.
- transforming growth factor (TGF), proteins crucial for tissue regeneration, and others, augment meniscus cell growth and subsequent collagen formation. Collagen is a building block of soft tissue.
Animal studies with these same growth factors have confirmed that meniscal tears and degeneration can be stimulated to repair with various growth factors or solutions that stimulate growth factor production.
In order to understand how growth factors affect the treatment of meniscus injuries, it is first important to understand the role that they play in the natural process of healing.
- The preliminary steps of healing begin with the attraction of blood cells to the site of injured tissue.
- When a tissue is injured, bleeding will naturally occur in that area.
- A specialized type of blood cells called platelets, rush to the area to cause coagulation, or the clotting of blood cells, to prevent excessive bleeding from an injury.
- In addition, platelets also release growth factors that are an integral part of the healing process.
Each platelet is made up of an alpha granule and a dense granule. For lack of a better term, these are “vessels” that contain a number of proteins and growth factors that are “poured” out onto the wound or injury. The growth factors contained in the alpha-granule are an especially important component of healing. When activated by an injury, the platelets will change shape and develop branches to spread over the injured tissue to help stop the bleeding in a process called aggregation, and then release growth factors, primarily from the alpha granules.
At this point, the healing process then proceeds in three simple stages: inflammatory, fibroblastic (formation of new connective tissue), and maturation (completion of the healing process).
In the case of the injured meniscus, it is clear that the damaged tissue can not repair itself. Healing in the meniscus depends on having enough of a blood supply and/or growth factors at the site of the injury. Since less than 20% of the meniscus is vascularized by the time a person reaches the age of 40 years, meniscal healing is generally incomplete.
In a recent study, German and Swiss doctors publishing in the Muscles, Ligaments and Tendons Journal. The doctors sought to demonstrate that Platelet Rich Plasma injections have the ability to regenerate tissue; as already shown in several experimental studies.
In this study:
- Ten recreational athletes with grade II meniscus tears were treated PRP injections into the affected meniscal area.
- Three sequential injections in seven-day intervals were performed in every patient.
- Four of ten patients (40%) showed a decrease of the meniscal lesion in follow-up MRI after six months.
- Six of ten patients (60%) showed Improvement of NRS-Score at the final follow-up.
- Average NRS-Score (A numeric scoring system for pain on a 1-10 scale) improved significantly from 6.9 before injections to 4.5 six months after treatment.
- Six of ten patients (60%) reported an increase in sports activity compared to the situation before injections.
- In four patients (40%) additional surgical treatment was necessary because of persistent knee pain or progression of the meniscal lesion. (6)
Recently, doctors at a military hospital in Pakistan treated patients with PRP and published the results: In their paper, they evaluated the clinical effects, adverse reactions and patient satisfaction after intraarticular injection of platelet rich plasma in a small group of patients with internal derangements of the knee. (Torn cartilage and Meniscus)
- 10 patients received two doses of 3 ml of platelet rich plasma as intraarticular knee injection at two weeks interval.
- All patients were evaluated at 0, 4 and 12 weeks after treatment using standard scoring systems
- There was a significant improvement in all scores.
They concluded intra-articular PRP injection is a safe and effective method in the conservative treatment of internal knee derangements.(7)
In our experience, using dextrose Prolotherapy with PRP together enhances the effectiveness of meniscal repair. When treating a meniscal tear with PRP Prolotherapy, the concentrated platelets (PRP) are placed at the site of the tear. Growth factors are released which will stimulate healing of the tear. The growth factors in the PRP will cause proliferation and regeneration of the injured tissue. This boosts fibroblastic events involved in tissue healing causing these tears to heal.
Five Platelet Rich Plasma Prolotherapy meniscus treatment cases presented in the medical literature
In 2010, our Caring Medical research team published our clinical observations on Platelet Rich Plasma Prolotherapy as a first-line treatment for meniscal pathology in the medical journal Practical Pain Management. (8)
In our paper, our goal was to not only show the effectiveness of PRP for meniscal tears but also provide evidence that treating the whole knee for instability by utilizing Prolotherapy, would lead to better PRP results.
Case Report #1
A 21-year-old runner athlete sustained a medial meniscal tear during wrestling. MRI revealed an oblique tear of the posterior horn of the medial meniscus. Because the patient failed physiotherapy and other conservative care the orthopedic surgeon recommended a partial meniscectomy. The patient’s parents were prolotherapy patients and hoped that prolotherapy would offer a non-surgical option for their son as well.
- The patient was complaining of pain with all activities except walking.
- He had popping in the knee and locking when trying to go from flexion to extension.
- Physical examination revealed medial joint laxity as well as a positive anterior drawer sign (A test for ACL instability and laxity).
The patient received one session of 3.5cc of platelet rich plasma prolotherapy to the inside of the knee. The anterior cruciate ligament and medial collateral ligament were treated with Hackett-Hemwall prolotherapy using a 15% dextrose, 10% Sarapin and 0.2% procaine solution as previously described.
- Prior to prolotherapy, the patient reported pain and stiffness levels of 5 (on a scale of 0 to 10) which decreased to 0 and 1, respectively.
- Prior to prolotherapy, he was completely incapacitated related to sports and after prolotherapy, he was back to running and exercising longer than 60 minutes.
- When he was questioned 15 months after the PRP prolotherapy session, he said prolotherapy had met his expectations.
Case Report #2
A 39-year-old squash player sustained a right knee injury while playing squash about one year prior to the visit. An MRI revealed a horizontal flap tear in the body of the lateral meniscus and the patient had a trial of physiotherapy without success. The patient did not want to get an arthroscopy which was suggested but instead sought out prolotherapy after an internet search.
- The patient complained of pain when running and was unable to play sports. He had crepitation in the knee but no locking. He complained of a deep ache within the knee. Physical examination revealed slight medial ligament laxity but no heat or swelling.
- He received two sessions of PRP prolotherapy to his knee, each with 3.5 mL of solution. He also received Hackett-Hemwall prolotherapy to his medial collateral ligament. The patient stated his pain and stiffness levels went from a 6 to a 1 after the prolotherapy. He reported that prior to prolotherapy he was completely incapacitated from running or playing squash but now, 17 months after his PRP prolotherapy treatment, he has no limitations.
Case Report #3
A 50-year-old chiropractor sustained medial and lateral meniscal tears after falling in a bicycling accident two years prior. He had tried previous conservative therapy without success in relieving his severe left knee pain. He was completely disabled as far as his previous activities of running and cycling. He did not want to undergo arthroscopy because of a poor response to an arthroscopy on his right knee several years before.
- Besides pain with any type of activity other than walking, he had popping and crepitation in the knee but no locking. He had pain deep within the knee as well as both laterally and medially. He had some generalized laxity of his knee throughout on physical examination.
- He received a total of four sessions of PRP prolotherapy to his knee over a one year period of time. His general laxity was also treated with Hackett-Hemwall prolotherapy. The primary reason for such a long time span is that each treatment gave him so much improvement he thought it was his last as he increased his physical activity, only to have some of the pain return. He was contacted twenty-four months after his last PRP prolotherapy session.
- Before the prolotherapy, he had a pain and stiffness level of 8 and 7 respectively, both of which decreased to a 1 after prolotherapy. He was unable to exercise before prolotherapy but after the PRP prolotherapy, he is able to engage in unlimited cycling and is able to run, but has chosen not to run because of his right knee (the one that had arthroscopy). He also said that PRP prolotherapy met his expectations.
Case Report #4
A 52-year-old athlete presented after sustaining an MRI-documented horizontal tear of the posterior horn of the lateral meniscus and oblique tear involving the postern horn of the medial meniscus after falling during running. He had a past history of partial lateral meniscectomy 20 years prior. His symptoms included diffuse knee pain and a feeling of his knee giving way. He also had occasional locking of the knee.
- On physical examination, he was found to have medial joint laxity as well as significant crepitation especially on the medial aspect of the knee. He received a single PRP prolotherapy treatment to his knee. At that time he also received Hackett-Hemwall prolotherapy for his medial knee instability.
- His pain level before prolotherapy was a 7 and stiffness also a 7 but, fourteen months post-PRP treatment, his pain level is 0 and stiffness is 1.
- He was unable to exercise at all before prolotherapy but after treatment, he can cycle for two hours and has no limitations with most weightlifting, all swimming, and all cycling. He cannot run currently because of an Achilles injury that he is thinking about getting treated with prolotherapy.
Case Report #5
A 46-year-old male with a history of three right knee surgeries and two on the left including partial meniscectomies on both knees presented for a prolotherapy evaluation because of presumed recurrent meniscal tears on both knees. The patient’s main sport is soccer but had a recent skiing injury that caused bilateral knee swelling and pain for one month prior to the first visit. The patient saw an orthopedist who ordered an MRI which showed the medial meniscal tears.
The patient was adamant about not wanting another knee surgery. He was on nonsteroidal anti-inflammatory medication, which was stopped once PRPP was begun. The complaints in both knees (the right was worse than the left) were swelling, popping and snapping and inability to run at all without significant pain. He felt both knees were unstable. The patient was completely disabled in regard to sports because of the injuries.
We have found PRP Prolotherapy to be a dependable and reliable treatment for meniscus tears.
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