Meniscus Tear Treatment | Stem cell tissue engineering
Ross Hauser, MD explains the various non-surgical treatments for Meniscus tear injury, this article highlights:
- Stem Cell Therapy regrows meniscus tissue. A single stem cell therapy injection following meniscus knee surgery can provide knee pain relief
- mesenchymal stem cells have the potential to improve the overall condition of the knee joint
- meniscal repair offers the potential to avoid the long-term articular cartilage deterioration that has been shown to result after meniscectomy
- Doctors say stem cell therapy will become the new clinical strategy for the treatment for meniscus tears
- Meniscus tears are particularly interesting because they are drastically on the rise. It’s estimated that one sixth of knee surgeries are performed for lesions on the meniscus, and many more go untreated every year. However, not all meniscus tears look exactly the same.
New Research on Stem Cell Therapy for Meniscus Tears
New research appearing in September 2015 acknowledges what we know: Arthroscopic meniscal repair and debridement are some of the most common procedures performed in the field of orthopedic surgeryand research suggests poor long-term outcomes for patients with meniscectomies with increased incidence of osteoarthritis.
This is why doctors need to develop technology to regenerate meniscal tissue following meniscectomy.
Mesenchymal stem cells, are cells that can be harvested from multiple organs and retain the ability to differentiate into a variety of tissues, including osteoblasts, adipocytes, and chondroblasts. They have been shown to stimulate the regeneration of meniscal tissue in several animal models and recently in humans, as well.1
Here is what doctors wrote in Stem Cell Therapy and Research April 2015:
- Meniscus injury is common and can lead to degenerative joint changes, given the current state of medical care, unless significant advancements are made in meniscus repair and regeneration technologies.
- Tissue engineering or in this case stem cell therapy aims to restore the structural and functional characteristics of meniscus by reconstructing the meniscus.
- A comprehensive review of the literature suggests that stem cell therapy possess an intrinsic therapeutic potential that can directly and indirectly contribute to meniscus healing.
- The future of meniscus tissue engineering lies in developing ways to maximally exploit the healing capacity of Stem Cells. 2
For many years, the primary treatment for a meniscal tear was a complete meniscectomy, a surgery that removed the entire meniscus from the knee. A typical patient profile for this procedure was a younger, active, athletic patient who through their lifestyle accelerated knee overuse, and, the older patient who suffered from degenerative osteoarthritis.
The goal of complete meniscectomy was to reduce pain, restore knee function, and prevent the development of osteoarthritis. As surgeons had long believed that the meniscus was a “remnant” tissue and that it was not needed, it could be removed if damaged without a negative effect.
However, as medical research studied the long-term effects of this procedure, it became apparent in the medical community that complete meniscectomy was a primary cause of the sudden onset of knee osteoarthritis. The meniscus was in fact an important component of the knee.
The meniscus (menisci plural) provides several vital functions including mechanical support, localized pressure distribution, and lubrication to the knee joint. They are made of thick fibrous cartilage that allows it to function as a shock absorber between the upper and the lower leg bones.
As an obvious important component of the knee It is now widely accepted in the medical community that the meniscus needs to be preserved through repair.
Even the American Academy of Orthopedic Surgeons was unable to come up with evidence to support the use of partial meniscectomy.3
They looked at a study by Herrlin et al. comparing arthroscopic partial meniscectomy to a conservative exercise program.
- The authors reported no significant treatment benefits of meniscectomy and at the 6 month follow up there was no difference noted between the two groups, “in terms of reduced knee pain, improved knee function and improved quality of life.” Not only was there no benefit, but it is important to note that surgical treatment for meniscal injuries can result in an acceleration of cartilage degeneration and an increased rate of osteoarthritis.
In new research from May 2015, doctors are trying to prove the best of both worlds by incorporating stem cell therapy into the meniscal surgery. The researchers say that there appears to be significant potential for biological augmentation and tissue engineering strategies in meniscus surgery to enhance options for repair and replacement.4 However they are not completely sold on using stem cells during surgery. Neither are we.
Menisci have two zones. The red zone is outside and the white zone is inside. Meniscus tears are characterized by their placement in these two zones.
- The longitudinal, or meniscus bucket handle, tear is a tear that tears vertically in either zone. It does not cut across the meniscus, but rather tears so that the curve looks like a bucket handle.
- A radial tear, on the other hand, is a tear that extends across both zones, starting at the red zone and then extending downward into the white zone. Radial tears are also called parrot beak tears because they make an open, angular shape that looks like a bird’s beak.
- A horizontal tear (or flap tear) is the exact opposite of a longitudinal tear; it cuts across the meniscus, as opposed to running alongside it.
- An oblique tear is a tear that is diagonal across the meniscus. When any of these patterns combine it is called a complex tear.
Acute meniscal tears
Acute meniscal tears can be enough of a problem on their own but are often coupled with acute ACL injuries. If you place enough force on your knee to tear meniscal tissue, you have likely placed enough force to injure other surrounding tissues as well. Meniscal tears will right away cause hemarthrosis, or bleeding in the joint. This is a classic presentation of intra-articular knee pathology, such as an acute meniscal tear (with or without acute ACL injury) and explains why the knee swells right away and becomes warm after injury. Because of this, it may be hard for practitioners to perform a proper physical exam on patients that come in with acute meniscal tears. In many cases, the bloody fluid may be drained and the patient is sent for an MRI. If an MRI shows a meniscal tear, arthroscopic surgery is likely recommended to fix the tear by most traditional medicine doctors and/or orthopedists.
Partial or Full Thickness Meniscus Tears
The other classification of meniscus tears is related to the depth of the tear. Tears are considered to either be partial thickness tears or full thickness tears. This is exactly what it sounds like. Partial thickness tears are tears that only extend part way across the meniscus, while full thickness tears extend fully across. So, if you have a full thickness flap tear, then it is a tear that cuts across the meniscus completely.
Meniscal surgery failure in 1 in 4 knees after 5 years
- “Meniscal repair” refers to the surgical repair of the meniscal cartilage.
- Meniscectomy refers to partial or complete removal of the meniscus of the knee.
In one recent study from the surgical journal The Journal of Arthroscopic and Related Surgery, the number of meniscectomies performed alarmed researchers. In fact it is concerning: “This study found that meniscectomy was performed in 65% of meniscus tears. This is concerning because studies have shown that, regardless of knee stability obtained after ACL reconstruction, meniscectomy accelerates degenerative joint changes.”5
Researchers now are convinced that it is better to repair the meniscus than remove it.
- “Meniscal repair offers the potential to avoid the long-term articular cartilage deterioration that has been shown to result after meniscectomy. Failure of the meniscal repair can occur several years postoperatively. Limited evidence on the long-term outcomes of meniscal repair exists.”6
These researchers sought to find out how patients did in the long term with a surgical repair of the meniscus as opposed to a removal of part or whole of the tissue.
- “A systematic review of the outcomes of meniscal repair at greater than five years postoperatively demonstrated very similar rates of meniscal failure (22.3% to 24.3%) for all techniques investigated.”7
The surgical repair and the surgical removal score about the same. A lot of failures.
the outcomes after arthroscopic partial meniscectomy were no better than those after a sham surgical procedure
On December 24, 2013, the New England Journal of Medicine published an article entitled :”Arthroscopic Partial Meniscectomy versus Sham Surgery for a Degenerative Meniscal Tear.”
This was the work of Finnish researchers who recognized that arthroscopic partial meniscectomy is one of the most common orthopedic procedures, yet rigorous evidence of its efficacy is lacking.
So what they did was to conducted a multicenter, randomized, double-blind, sham-controlled trial in 146 patients 35 to 65 years of age who had knee symptoms consistent with a degenerative medial meniscus tear and no knee osteoarthritis.
Patients were randomly assigned to arthroscopic partial meniscectomy or sham surgery. Then a scoring system was designed to measure pain, symptom severity and knee pain after exercise at 12 months after the procedure.
What they found was “In this trial involving patients without knee osteoarthritis but with symptoms of a degenerative medial meniscus tear, the outcomes after arthroscopic partial meniscectomy were no better than those after a sham surgical procedure.”
This is not the first study this year to question the value of meniscal surgery. Earlier in 2013 research published in the American Journal of Sports Medicine showed what little value meniscectomy has. Researchers compared meniscectomy to nonoperative treatment for meniscus tears.8 They specifically studied degenerative horizontal tears of the medial meniscus and hypothesized that surgical treatment would produce better outcomes that nonoperative strengthening exercises.
This study was a randomized controlled trial with the highest level of evidence (level 1). The study had 102 patients with medial meniscus tears – 81 women and 21 men with the average age of 53.8.
Fifty patients underwent arthroscopic menisicectomy while 52 participated in nonoperative strengthening exercises. The results did not match up the to researchers hypothesis. At the two year follow-up there was no difference in pain relief, improved knee function or patient satisfaction. Results also showed that meniscectomy did not provide better functional improvement than the nonoperative group.
But what was the difference between these two groups? One group of patients underwent invasive surgery, had tissue remove, and will likely experience long-term meniscus degeneration.
In fact, most surgical meniscus treatments have, “all have a high long-term failure rate with the recurrence of symptoms including pain, instability, locking, and re-injury. The most serious of the long-term consequences is an acceleration of joint degeneration.”
So, even if the knee is stabilized, removing the meniscus causes osteoarthritis. Consider this conclusion from a medical paper published in late 2014:
In this study from China, doctors said that arthroscopic partial meniscectomy is a good option for medial meniscal tear in late middle-aged adults. For best success you need a proper diagnosis and excellent surgical technique. If you follow these two rules all the patients could get good clinical results, HOWEVER, “there are some patients with motion restrictions in the early stage after operation.” 9
Meniscus Surgery Alternatives
In research in the Journal of Bone and Joint Surgery, doctors have found that a single stem cell injection following meniscus knee surgery may provide knee pain relief and aid in meniscus regrowth. In this study, patients received a single injection of adult stem cells following the surgical removal of all or part of a torn meniscus. These patients reported a significant reduction in pain. Further, some meniscal tissue regrew! Up to 15 percent increase in meniscal volume at one year. There was no additional increase in meniscal volume at year two. (Comment: Maybe they should have given more than one injection.)
That question was answered in the American Academy of Orthopaedic Surgeons‘ press release. “The results of this study suggest that mesenchymal stem cells have the potential to improve the overall condition of the knee joint,” said Dr. Vangsness (a study author). “I am very excited and encouraged” by the results. With the success of a single injection, “It begs the question: What if we give a series of injections?”10
Meniscus repair with Stem Cell Therapy
Again, we have to ask, if it works so well in rebuilding meniscal tissue, why have the surgery in the first place? It does say multiple injections may benefit the patient more. It seems we have written very often that single injections are not Prolotherapy; single PRP (Platelet Rich Plasma) injections are not PRP treatments; and now single Stem Cell Therapy injections are probably more effective if given more often? Sounds like Comprehensive Prolotherapy performed at Caring Medical, ie multiple injections of various and supportive elements to fit the individual case of the the patient. Please read our more extensive article on this subject Stem Cell Therapy regrows meniscus tissue
Meniscus Tear Treatments Stem Cell Therapy, Platelet Rich Plasma Therapy and Prolotherapy
Osteoarthritis of the knee is not merely an articular cartilage disease, but a disease of the whole joint. Comprehensive Prolotherapy treats the whole joint.
For extreme cases of joint degeneration, stem cell injection therapy or Bone Marrow Prolotherapy is used. In this procedure bone marrow (with its stem cells) is used as the proliferant for inside the joint. It has been shown in other studies that bone marrow stem cells can be used to regenerate meniscus tissue. The extent of joint degeneration will determine what solutions are used and how many visits are needed.
A group of researchers at Hiroshima University in Japan studied surgical alternatives to a torn meniscus. They were aware of the poor outcome of meniscectomies and of alternative treatments. They did, however, hear of the promising results of using mesenchymal stem cells in regenerating and repairing tissue. They conducted a study that transplanted mesenchymal stem cell from the tibia of rats to the torn meniscus in each rat. The stem cells were taken from the bone marrow of the tibia, harvested and transplanted into the torn meniscus. The results were promising, showing that mesenchymal stem cells could in fact proliferate and contribute to the healing of menisci. The results were so promising that they concluded “we are confident that the mesenchymal stem cell transplantation will become the new clinical strategy for the treatment for meniscus tears.”11
In 2010 we published our findings on Prolotherapy for meniscal tears. We perfromed a retrospective study involving 24 patients, representing 28 knees, whose primary knee complaints were due to meniscal pathology documented by MRI. The average number of Prolotherapy visits was six and the patients were followed on average 18 months after their last Prolotherapy visit. Prolotherapy caused a statistically significant decline in the patients’ knee pain and stiffness. Starting and ending knee pain declined from 7.2 to 1.6, while stiffness went from 6.0 to 1.8.
Patients stated that the response to Prolotherapy met their expectations in 27 out of the 28 knees (96%). Only one out of the 28 patients ended up getting surgery after Prolotherapy.
Based on the results of this study, Prolotherapy appears to be an effective treatment for meniscal pathology. 12
Platelet Rich Plasma is effective for meniscus repair
Caring Medical has conducted research which shows the effectiveness of PRP Prolotherapy, including case reports of MRI-documented meniscus tears successfully treated with PRPP. 13 Other research demonstrates that PRP promotes significant healing of the meniscus.14
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.
PRP Prolotherapy is effective at healing meniscal injuries without the need for surgery
Caring Medical research has shown that improvement with dextrose Prolotherapy alone met the patients’ expectations in over 96% of the knees to the point where surgery was not needed.15 However, in cases where a stronger proliferating solution is necessary, and PRP is used in conjunction with Dextrose Prolotherapy, the results are outstanding. Prolotherapy with or without PRP is a first-line treatment consideration for meniscal injuries, and an effective alternative to surgery.
Patients with meniscal injuries as well as those with knee osteoarthritis are commonly led to believe that surgery is their only option. Conservative management is often overlooked in the quest to send patients for surgical referral. One researcher states, “Few conservative management options were tried before referral, indicating the need to enhance pre-surgical care for patients with knee osteoarthritis.”16
Interestingly, in a trial “involving patients with symptoms of a degenerative medial meniscus tear, the outcomes after arthroscopic partial meniscectomy were no better than those after a sham surgical procedure.”17 There are quite a few studies showing no benefit from this type of surgery compared to more conservative treatments. This study, however, clearly demonstrates NO benefit from arthroscopic partial meniscectomy compared to fake surgery. These results certainly raise some concern. On our website is a more detailed article on mensicus tears and treatment with PRP Stem Cell Therapy and Prolotherapy.
Meniscus Surgery Alternatives
With the rise of biologic technologies including stem cells, many patients are now turning to Meniscus Tear surgery options including Stem Cell Therapy, Platelet Rich Plasma Therapy, and Stem Cell Therapy. These treatments regenerate meniscus tissue.
References for this article
1. McCrum CL, Vangsness CT. Postmeniscectomy Meniscus Growth With Stem Cells: Where Are We Now? Sports Med Arthrosc. 2015 Sep;23(3):139-42. doi: 10.1097/JSA.0000000000000073.
2. Yu H,Adesida AB, Jomha NM. Meniscus repair using mesenchymal stem cells – a comprehensive review. Stem Cell Res Ther. 2015 Apr 30;6(1):86. doi: 10.1186/s13287-015-0077-2.
3. Herrlin S, et al. Arthroscopic or conservative treatment of degenerative medial meniscal tears: a prospective randomised trial. Knee Surg Sports Traumatol Arthrosc. 2007;15(4):393-401.
4. Moran CJ, Busilacchi A, Lee CA, Athanasiou KA, Verdonk PC. Biological Augmentation and Tissue Engineering Approaches in Meniscus Surgery. Arthroscopy. 2015 May;31(5):944-955. doi: 10.1016/j.arthro.2014.11.044. Epub 2015 Feb 14.
5. Noyes FR, Barber-Westin SD. Treatment of meniscus tears during anterior cruciate ligament reconstruction. Arthroscopy. 2012 Jan;28(1):123-30. doi: 10.1016/j.arthro.2011.08.292. Epub 2011 Nov 9.
6. Nepple JJ, Dunn WR, Wright RW. Meniscal repair outcomes at greater than five years: a systematic literature review and meta-analysis. J Bone Joint Surg Am. 2012 Dec 19;94(24):2222-7. doi: 10.2106/JBJS.K.01584
7. A Comparative Study of Meniscectomy and Nonoperative Treatment for Degenerative Horizontal Tears of the Medial Meniscus Am J Sports Med May 23, 2013 ; published online before print May 23, 2013.
8. Zhongguo Gu Shang Arthroscopic partial meniscectomy for medial meniscal tear in late middle-aged adults. 2014 Aug;27(8):631-4.
9. Stem Cell therapy following Meniscal Surgery http://newsroom.aaos.org/media-resources/Press-releases/stem-cell-therapy-following-meniscus-knee-surgery-may-reduce-pain-restore-meniscus.htm
10. Izuta Y, et al. Meniscal repair using bone marrow-derived mesenchymal stem cells: experimental study using green fluorescent protein transgenic rats. The Knee. 12 (2005) 217 – 223.
11. Hauser R, Phillips H, Maddela HS. Hilary J. The Case for Utilizing Prolotherapy as First-Line Treatment for Meniscal Pathology: A Retrospective Study Shows Prolotherapy is Effective in the Treatment of MRI-Documented Meniscal Tears and Degeneration. Journal of Prolotherapy. 2010;(2)3:416-437.
12. Hauser R, Phillips HJ, Maddela HS. Platelet Rich Plasma Prolotherapy as First-line Treatment for meniscal pathology.Practical Pain Management. 2010;July/August:53-64.
13. Wei LC, et al. A novel hypothesis: The application of platelet-rich plasma can promote the clinical healing of white-white meniscal tears. Med Sci Monit. 2012 Aug;18(8):HY47-50.
14. Hauser R, Phillips HJ, Maddela HS. The case for utilizing Prolotherapy as first-line treatment for meniscal pathology: a retrospective study shows Prolotherapy is effective in the treatment of MRI-documented meniscal tears and degeneration. Journal of Prolotherapy. 2010;2(3):416-437.
15. Klett MJ, Frankovich R, Dervin GF, Stacey D. Impact of a surgical screening clinic for patients with knee osteoarthritis: a descriptive study. Clin J Sport Med. 2012 May;22(3):274-7.
16. Sihvonen R, et al. Arthroscopic partial meniscectomy versus sham surgery for a degenerative meniscal tear. N Engl J Med. 2013; 369:2515-2524.
17. Lowry F. Real knee surgery no better than sham for meniscal tear. Medscape Medical News. December 27, 2013.