ACL reconstruction surgery alternatives and treatment options | Prolotherapy, PRP and stem cells
Is ACL reconstruction surgical repair the right option for every athlete? In this article Ross Hauser, MD reviews the latest medical research that can help the patient / athlete understand their ACL pre and post surgery challenges and how treatments that include Prolotherapy, PRP and stem cells may offer surgical options and accelerated recovery. See our main page, Prolotherapy for knee pain for more information.
If you have questions about ACL reconstruction options, you can get help and information from our Caring Medival Staff
This is a multi-part article on ACL surgical options. Other segments include:
Do you need an ACL to play recreational sports? “Whether surgical or conservative treatment is more effective in allowing patients to return to physical activity after anterior cruciate ligament (ACL) injury is controversial.”
A paper published in December 2017 by Turkish physicians in the journal Acta orthopaedica et traumatologica turcica weighed in on the ACL surgery or not debate.
“Whether surgical or conservative treatment is more effective in allowing patients to return to physical activity after anterior cruciate ligament (ACL) injury is controversial. We sought to compare mid-term outcome measures between isolated ACL tear patients who underwent reconstruction followed by closed kinetic chain exercises and those who underwent neuromuscular training only.”
Okay so in this study, what was the outcome?
“No statistical difference was observed between the groups for any of the parameters evaluated, including assessment of subjective knee function, one-leg hop test, assessment of joint position sense, muscle strength, and the health profile.”
“Our data suggest that early surgical reconstruction may not be a prerequisite to returning to recreational physical activities after injury in patients with ACL tears.”(1)
You do not need ACL reconstruction surgery to return to play. I do realize that this is a hot-button suggestion and that many people will point to professional athletes as proof of the need of an ACL reconstruction surgery. Please keep reading, there is so much more to discuss.
Is ACL reconstruction surgery a guarantee to return to play? Hardly
New research from Brown University presents the return to play reality: “Accelerated rehabilitation has made recovery from surgery more predictable and shortened the timeline for return to play (from ACL reconstruction surgery). (However) Despite success with advancements in anterior cruciate ligament reconstructions, some athletes still fail to return to play.”(2)
ACL reconstruction does provide remarkable short-term knee stability. Unfortunately, the stability doesn’t last because no matter how hard the surgeons try, they can not simulate exactly the same biology pre-injury. If a patient has grade 3 ligament tear, and the patient deems the ACL necessary, surgery is indicated. The cadaver or tendon graft that is replacing the torn ligament, however, will not function long-term like the original ACL.
The long-term results from many studies demonstrate that untreated joint instability remains.
The long-term results from many studies demonstrate that untreated joint instability remains. Doctors from the Hospital for Special Surgery and Cornell Medical Center Program in New York reported in the Orthopaedic journal of sports medicine of the over 23,000 pediatric patients who underwent ACL reconstruction:
- 8.2% had a subsequent ACL reconstruction and
- 14% had subsequent non-ACL knee surgery.
The median time lapse between the first and second surgeries were 1.4 and 1.6 years, respectively.(3)
- It was noted that this may be a conservative number of patients who had repeat tears, as the data only included those who underwent a second surgery, and not those who decided not to have the additional surgery.
Failure of primary ACL reconstruction can be attributed to:
This is pointed out by Italian researchers who in part blame the ACL failure on compromised ligaments and the meniscus of one or both knees. Published in the Sports medicine and arthroscopy review, here are the highlights of this research:
- The number of patients undergoing ACL revision surgery following failure of anterior cruciate ligament reconstruction has increased.
- Failure of primary ACL reconstruction can be attributed to:
- technical errors,
- tunnel malposition (see below), untreated associated ligaments insufficiencies (see below), uncorrected lower limb malalignment, and graft fixation failures (the graph re-ruptured).
- new traumatic injuries
- biological failures, the new ACL failed, sometimes this is due to secondary deterioration in the other knee ligaments and meniscus.(4)
- The relationship between meniscus damage and the ACL failure is well understood. In new research from March 2017, doctors at the University of Toronto and the Cleveland Clinic showed clinically significant knee pain is more common following injuries to the medial meniscus and increased in patients who undergo early re-operation (revision surgery) after initial ACL reconstruction. These researchers suggest focus on repairing the medial meniscal tears sustained during ACL injury and a re-evaluation of the ACL surgery decision and timeline.(5)
- technical errors,
Where is the role of knee instability in ACL repair? April 2018, 20 year follow up. Patients who had ACL reconstructive surgery more likely to have knee osteoarthritis than those who did not.
Doctors at Erasmus University Medical Center, Rotterdam, the Netherlands looked at fifty patients who had an ACL rupture from the 1990’s. Twenty-five patients were treated nonoperatively in 1992, consisting of structured rehabilitation and lifestyle adjustments. Twenty-five were surgical treated between 1994 and 1996 with ACL reconstruction featuring a patella tendon.
- The patients in the nonoperative group were drawn from those who responded well to 3 months of nonoperative treatment, whereas the patients in the operative group were drawn from those who had persistent instability after 3 months of nonoperative treatment and then sent to surgery.
- After 20 years, we found knee osteoarthritis in 80% of the operative group compared with 68% of the nonoperative group
- Although knee stability was better in the operative group, it did not result in better subjective and objective functional outcomes.(6)
What this research suggests is that ACL reconstruction therapy may not provide the overall knee stability needed to prevent degenerative knee disease.
Joint instability is the missing diagnosis for athletes with ACL tears
It makes no sense that a person is subjected to multiple surgeries when it is obvious that joint instability is the cause of the problem. Joint instability is the missing diagnosis for athletes with ACL tears, and additional surgeries, no matter how sophisticated, are not the answer to the problem of joint instability. Pain, swelling, weakness, popping, grinding, and other symptoms associated with ACL tears can be addressed not with surgery, but with Prolotherapy.
We see many patients following ACL reconstruction surgery for Prolotherapy. They come in once their knee feels unstable and weak. As extensive independent research points out, the long-term results of initial ACL reconstruction demonstrate that untreated joint instability remains. After an examination, we recommend patients consider comprehensive Prolotherapy to treat the whole knee complex to help prevent need for secondary surgery and to accelerate ACL reconstruction surgery recovery time. We discuss these points further below.
Patients expectations of excellent results in ACL reconstruction surgery not met
What are excellent results in ACL reconstruction surgery? That is hard to say. The problem is that orthopedic surgeons’ perspectives of excellent results are different than athletes’ perspectives.
As mentioned above, one of the main reasons for having the ACL surgery was the ability to return to sports. For many this was not achieved.
Doctors from the Karolinska Institutet in Sweden found that patients saw no real choice between operative and non-operative treatment. Athletes perceived surgery as the only way to fully return to the pre-injury level of sports, and surgery was understood as the only way to become a completely restored “functional human being”.
A major source of frustration to the patients was that the progress during the ACL rehabilitation process did not match their expectations, fear of re-injury became common.
- Complications and knee problems after the surgery were common.
- Patients reported pain including behind the knee, knee swelling and knee popping
- Fear of re-injury was common.
- Other challenges were the commitment to staying with the ACL recovery timeline and demands of physical therapy.
Some participants because expectation of surgical success was not met decided not to return to their sports.(7)
So there is a question as to whether or not ACL reconstruction surgery is the best option. Here is a study on high school and college football players.
This question, whether or not ACL reconstruction is the best option, was further raised by researchers at Vanderbilt University Medical Center. Doctors there noted the lack of data regarding the effect of anterior cruciate ligament reconstruction on the ability of American high school and collegiate football players to return to play at the same level of competition as before their injury or to progress to play at the next level of competition.
- 43% of the players were able to return to play at the same self-described performance level.
- Approximately 27% felt they did not perform at a level attained before their ACL tear, and
- 30% were unable to return to play at all.
Although two thirds of players reported some “other interest” contributing to their decision not to return, at both levels of competition, fear of reinjury or further damage was cited by approximately 50% of the players who did not return to play.”(8) Results that mimic those cited above.
Recently researchers in the United Kingdom put together a paper on best practices of when and type of ACL surgery to consider.
Here is a summary: The aim of ACL surgery is to restore functional stability to the ACL deficient knee. ACL reconstruction can be performed using a variety of different surgical techniques as well as different graft materials.
- The choice of whether to operate or not relies on many factors and is highly dependent on patient’s degree of symptoms and requirements in terms of activity level and participation in pivoting sports.
- Many patients can become symptom-free following a course of physical therapy and rehabilitation.
Timing of any ACL reconstruction is also crucial, it is commonplace to allow the acutely injured knee to settle, giving time for resolution of swelling, restoration of range of motion and recovery from of concomitant ligament injuries. (I discussed this above in regard to meniscus injury).
Furthermore a delayed reconstruction allows patients to try conservative therapy to see if surgery is indicated. (This is discussed at length below)
The three categories of commonly used grafts are:
- autograft, usually consist of either hamstrings tendons or Bone-patella tendon-bone (BPTB).
- allograft, Allografts are varied but can consist of tibialis posterior tendon, Achilles tendon, tibialis anterior tendon, BPTB and peroneus longus tendon.
- and Synthetic graft. Synthetic grafts have been developed over the years and are currently on their “third generation” but have encountered considerable problems in the past
The surgical technique used during ACL reconstruction varies widely. Different techniques include arthroscopic vs open surgery, intra vs extra-articular reconstruction, femoral tunnel placement, number of graft strands, single vs double bundle and fixation method.(9)
Complete or a partial ACL tear, is ACL surgery is necessary? Some patients exhibit little or no symptoms when they play low-demanding sports or activities.
Generally with a documented complete rupture, the patient has a choice of reconstruction surgery or non-surgical options. The non-surgical options would include first: A realistic assessment of future activities on an ACL-deficient knee. Some patients exhibit little or no symptoms when they play low-demanding sports or activities.
Here are the arguments for operating on a partial ACL tear:
Research from a combined team at Rush University Medical Center, Columbia University Medical Center, and the Hospital for Special Surgery:
- The optimal treatment for a partial anterior cruciate ligament (ACL) tear continues to be a subject of considerable debate.
- A question remains whether it is advantageous to preserve the ACL remnant and augment it with a graft, or get rid out it and start all over. Clinical outcomes of ACL preserving surgery are promising. An increasingly large body of scientific evidence suggests that augmenting the intact bundle is beneficial in terms of vascularity, proprioception and kinematics.(10)
This is what doctors at Oxford University asked: They suggest that patients should always take caution when any type of joint surgery is recommended, and reconstruction of the anterior cruciate ligament (ACL) is no different. It is widely known that many patients who undergo ACL reconstruction experience a chronic “giving way” feeling after the surgery and some encounter a re-rupture of the tendon.(11)
Biomaterials Prolotherapy, PRP and stem cells in partial ACL tears
We have already touched on treatment with Prolotherapy. In January 2017, doctors writing in the Orthopedic journal of sports medicine, wrote of the controversies surrounding repair of partial ACL tears. One of the controversies was reconstructive surgery. In this study the researchers found that biologically augmented ACL-repair techniques (PRP and stem cells) improve healing and outcomes of both the native ACL (non-surgery) and the reconstructed graft tissue (surgery).(12)
In 2003, K. Dean Reeves, MD published in the journal Alternative therapies in health and medicine (13) these findings:
- 16 knees with machine measured ACL laxity were injected bimonthly with 10-25% dextrose solution (Prolotherapy) for 1 year and then an average of 4 times yearly thereafter until 3 year follow-up.
- Summary: Using simple dextrose injection into 16 knees with a loose ACL ligament,
- 10/16 knees were no longer loose by machine measurement at time of follow-up, and symptoms were improved.
- Symptom of osteoarthritis improved even in those who still tested loose.
- At the 3 year follow-up pain with walking had improved by 43% , subjective swelling improved 63%, flexion range of motion improved by 10.5 degrees, and machine measure of ACL ligament looseness improved by 71%.
The realities of non-surgical ACL regeneration
Stem Cell Therapy and Prolotherapy – Non-surgical ACL reconstruction?
Doctors at the Department of Trauma Surgery and Sports Injuries, University Hospital of Salzburg wrote in the Archives of orthopaedic and trauma surgery:
“The ACL has the potential to heal upon intensive non-surgical rehabilitation procedures. Several biological factors influence this healing process as local intraligamentous cytokines (messengers that call for more inflammation (healing)) and mainly cell repair mechanisms controlled by stem cells or progenitor (creator) cells. Understanding the mechanisms of this regeneration process and the cells involved may pave the way for novel, less invasive and biology-based strategies for ACL repair.”(14)
In 2015, doctors in China excitedly published research in the Chinese journal of reparative and reconstructive surgery which said: “Enormous progress has been made in tissue engineered ligament for repair and regeneration of ACL. With the development of biochemistry and scaffold materials, tissue engineered ligament will be used in clinic in the near future.”(15)
This research suggests that one day doctors will be able to grow a new ACL in the laboratory and implant it into a knee. That is fantastic news for the people of the future but what about today? Is there a way today to non-surgically repair a damaged ACL? Do you even need to replace the ACL?
Another team of Chinese researchers writing in the medical journal International orthopaedics noted that the ACL has certain self-healing abilities after acute injury. These self-healing abilities have to do with stem cells (for a detailed discussion on how stem cells work please see my article on stem cell therapy). The Chinese team suggested that leaving behind part of the ruptured ACL remnant would release native stem cells into the new graft and augment healing. In addition, taking stem cells from the remnant ACL may be a potential source of seeding cells for ligament regeneration.(16)
This research found agreement in the work of Korean doctors who wrote in the medical journal Current stem cell research and therapy of recent developments in mesenchymal stem cell (MSC)-based approaches for enhancing healing after ACL injuries. They suggest that stem cells are a promising treatment options for enhancing biologic healing of ACL grafts and restoring the functional properties to the levels of the native ACL, and ultimately improving clinical outcomes.(17)
What this research suggests is stem cell augmentation for the ACL graft to prevent ACL complications.
The complexity of an ACL tear – Is it full? Partial? Can it regenerate on its own in the proper circumstance?
In 2009, Prolotherapy doctors led by Walter Grote MD, published a case history of an 18-year old female patient who returned to sports after a high-grade partial (possibly complete) ACL rupture.
This case report, published in the medical journal International musculoskeletal medicine, documented the successful non-surgical repair of an MRI-confirmed high grade or total ACL tear in an 18 year old female with knee laxity and instability using prolotherapy and at-home exercise. After treatment, the patient regained full knee function, resumed normal activity and returned to recreational sport. Post-treatment MRI revealed a healing chronic ACL tear. These findings are notable given that surgical ACL reconstruction is the conventional treatment for ACL tears with such clinical presentation.
As exciting as this sounds, Dr. Grote and colleagues noted that there were too many factors in this ACL healing to confirm it was caused by Prolotherapy treatment alone. Listen carefully to what this case history presented:
Was the MRI of a complete ACL rupture even accurate?
- “While MRI is the diagnostic imaging technique of choice, it is not perfect. The tear may have therefore have been near-complete, or the severed ends of the ligament may have been in close enough approximation to facilitate natural healing.”
- The inaccuracy of MRI is well documented, in this case study it could not be relied on to give an accurate reading. Please see my article on the MRI accuracy for determining the need for surgery. In this study, while MRI suggested a complete rupture, it may not have been a complete rupture.
The conclusion: The limitations above prevent a categorical conclusion that prolotherapy alone contributed to or restored pain-free function and improved the appearance of the MRI. However, the facts of this case and the context provided by prior clinical trials suggest that prolotherapy at least augmented the healing a high grade or total ACL tear. These findings further suggest that prolotherapy may be an alternative treatment to surgery for carefully selected patients and should be assessed as a treatment of ligamentous tears, especially in patients who are unwilling or unable to undergo surgical intervention.” (18)
So what to do with an ACL tear?
I believe the best treatment for grade 1 or grade 2 tear is Prolotherapy. If someone has a complete ACL tear they should get a consultation with a doctor who specializes in regenerative medicine to decide if surgery or non-surgical option is the way to go. If surgery is the route to take, based on the patient’s desire to return to high-level competitive sport, then after surgery, Comprehensive Prolotherapy to help provided strengthened stability to the whole knee.
The ACL and degenerative meniscus disease
Patients who have ACL reconstructive surgery and those who forgo ACL reconstructive surgery are both at high risk for osteoarthritis of the knee. This was demonstrated in the research above and in new research from a team of Chinese researchers who publishing in the April 2018 edition of the American Journal of Sports Medicine found that the deterioration of meniscus was more extensive than that of articular cartilage and subchondral bone in animal studies. Partly in due to chronic inflammation and osteoarthritic changes to the extracellular matrix (the healing soup of cells). The fascinating subject of how Extracellular Matrix repairs cartilage is explained in our article. The researchers of this study noted that rupture of the ACL induced changes that not only could explain the contribution of the meniscus to the progress of osteoarthritis but also could provide a cue for initiation of preventive treatments in the early stages of osteoarthritis.(19)
In other words, treat knee instability to prevent meniscus damage and degenerative meniscus disease. The box below has supportive information on our treatment methods for meniscal injury.
More research and patient outcomes can be found here:
Prolotherapy for Meniscus Tears One of the most common calls our office receives involves patients who have had part or all of their meniscus removed and are suffering with continued pain or arthritis that was accelerated due to the surgery. Meniscectomies worsen knee joint instability by negatively influencing other supporting knee structures, increasing contact stress, and leading to arthritis.
Platelet rich plasma injections for meniscus tears In this article Ross Hauser, MD explores 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.
Bucket handle meniscus tear repair and treatment options In this article we present information on the bucket handle meniscus tear sometimes overlooked in the doctor-patient consultation. Not all bucket handle meniscus tears need to be operated on. The reasons are presented below.
Knee Surgery for Meniscus Tears | Complications and Outcomes One of the most common calls our office receives involves patients who have had part or all of their meniscus removed and are suffering with continued pain or arthritis that was accelerated due to the surgery. Meniscectomies worsen knee joint instability by negatively influencing other supporting knee structures, increasing contact stress, and leading to arthritis.
Stem Cell Prolotherapy injections for knee meniscus tears and post-meniscectomy With the rise of biologic technologies including stem cell technology and continued research calling arthroscopy surgery for meniscus tear in question, many patients are now exploring non-surgical meniscus regeneration with Stem Cell Prolotherapy.
The many types of meniscus tears In this article we provide background information on the many types of meniscus tears and how they can be treated with a non-surgical Comprehensive Prolotherapy approach.
Meniscus scaffolds When is comes to the science of stem cells and the meniscus, patients are often confused by what types of treatments are available today and what type of treatments will be available in the future.
The ACL and PCL (posterior cruciate ligament). The problems of identifying the source of ligament laxity and knee instability
The anterior cruciate ligament sits in front of the PCL and together the ACL and PCL keep the tibia (shin bone) from sliding too far forward and the tibia in position below the femur (thigh bone). The PCL, is the knee’s basic stabilizer and almost twice as strong as the ACL.
A 2018 study in the Journal of Surgery discusses the problems of identifying the true nature of knee instability causes and this research surrounds the PCL.(20)
The researchers noted that “ACL tear in concomitant chronic ACL and posterior cruciate ligament (PCL) deficient knees may produce knee laxity, which is more difficult to assess on clinical examination, which in turn may affect the management algorithm of the patient.”
In our article Posterior Cruciate Ligament Injury and Treatments, we identify this problem and discuss the treatment of PCL damage. Briefly we suggest: “Posterior cruciate ligament (PCL) injuries make up between 3 and 20 percent of all knee ligament injuries. However, PCL injuries are often left diagnosed. Why it is left undiagnosed and untreated is because the PCL is not well understood.”
Understanding and strengthening the PCL is an important factor in ACL injured knees.
All the ligaments of the knee work to stabilize an ACL injury and ACL deficient knee
The ACL’s job is to prevent the tibia and the femur from moving excessively on each other. When it is injured or not there, it puts stress on the other ligaments to prevent this excessive motion.
If you are debating ACL reconstruction because of long rehabilitation, unsureness that the surgery will be successful, already had one ACL reconstruction. Please consider a consultation. What we will discuss with you is:
- Surgery or non-surgical approaches
- The use of Prolotherapy, PRP, or stem cell treatments
- Realistic expectation of surgery and non-surgical treatment
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