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, or PRP injections for meniscus tears as an option.
- If you have questions about your meniscus injury, email us for help and information
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.
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 which re-introduces your own concentrated blood platelets into areas of chronic joint and spine deterioration.
The video below will help you understand the treatment process of PRP / PRP Prolotherapy
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?
Doctors at Department of Orthopaedics, Xiangya Hospital, Central South University in China published their research in the journal Medical science monitor.
In this research they discuss the meniscus white-white tears which they describe as “a meniscus lesion completely in the avascular zone (which) 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.(1)
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.
Meniscal Surgery: a poor option that PRP intervention at the time of surgery 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.(2)
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 meniscal 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 in the surgical outcome. Before we go on, a quick citation is needed to help with understanding of 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%. (3)
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.”2
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.
Medical reviews of PRP meniscus injections
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 an 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 which 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” which contain a number of proteins and growth factors which are “poured” out onto the wound or injury. The growth factors contained in the alpha-granule are an especially important component to healing. When activated by an injury, the platelets will change shape and develop branches to spread over 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 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 the 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 decrease of meniscal lesion in follow up MRI after six months.
- Six of ten patients (60%) showed Improvement of NRS-Score at 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 month after treatment.
- Six of ten patients (60%) reported increase of 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 meniscal lesion.(4)
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 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 significant improvement in all scores.
They concluded Intra-articular PRP injection is safe and effective method in the conservative treatment of internal knee derangements.(5)
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 a proliferation and regeneration of the injured tissue. This boosts fibroblastic events involved in tissue healing causing these tears to heal.
Five PRP Prolotherapy cases studies presented in the medical literature
In 2010, our Caring Medical and Rehabilitation Services research team published our clinical observations on Platelet Rich Plasma Prolotherapy as first-line treatment for meniscal pathology in the medical journal Practical Pain Management.(6)
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 cc 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, 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 get arthroscopy because of a poor response to an arthroscopy on his right knee several years before.
- Beside 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 weight lifting, 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 causing 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.
If you have questions about your meniscus injury, email us for help and information
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