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ACL Tears

Causes, Symptoms, Treatment Options, & Other Resources

What are ACL Tears?

The Anterior Cruciate Ligament (ACL) is one of four major ligaments in the knee. It is an important stabilizer of the knee and prevents the shin bone (tibia) from sliding in front of the thigh bone (femur).

The ACL is susceptible to injury. It is most likely to be injured during activity or by impact.

A torn ACL is a common injury for athletes at all levels, but it is most common for people who are active or who experience impact injuries to the knee. 

Causes of ACL Tears

ACL injuries can happen to anyone of any age, condition, or ability, and they can be injured in many ways. Examples include abruptly changing direction, slowing down while running, landing incorrectly, or getting struck by someone or some object.

Several studies have shown that female athletes can get ACL injuries at a higher rate than male athletes. It has been proposed that this is because of differences in physical conditioning, muscular strength, and neuromuscular control. Other causes include differences in how the pelvis fits with the leg and ligaments’ integrity. Estrogen also is considered to play a part in why this may be the case. 

About half of all injuries to the anterior cruciate ligament happen along with other damage in the knee. Examples include damage to the articular cartilage, meniscus, or other ligaments such as the medial collateral ligament.

Orthopedists categorize ACL tears into 3 grades:

Grade 1 Tears

A partial-thickness ACL tear is a type of ACL tear where only a portion of the ACL is torn. This can be treated by Perc-ACLR.

Grade 2 Tears

A full-thickness, non-retracted ACL tear is when the ligament has been torn completely. The ligament still has not pulled apart or snapped back. This can be treated with the Perc-ACLR.

Grade 3 Tears

A grade 3 tear is a full-thickness tear that extends across the ACL and unlike a Grade 2 the ligament has pulled apart. This means that the two pieces of the ligament have pulled apart or maybe even snapped back like a rubber band. This cannot be treated with Perc-ACLR.

Symptoms of ACL Tears

Back of Knee Swollen

Back of knee swollen? Swelling in the back of the knee is not something that is talked about too often. It can be uncomfortable or sometimes painful with the movement of the knee or, even with rest. It often stems from an orthopedic-related issue or, perhaps some other medical condition. Let’s dive in…What’s Causes Swelling in the Back of Your Knee? The back of the knee contains a variety of anatomical structures that can be affected and result in pain, swelling, numbness, tingling, etc. Muscles and tendons behind the knee that could be the source of pain or pathology could be one or more of the following: Gastrocnemius, Soleus…

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Can’t Straighten Knee

Your knee is capable of moving in a number of directions. The most common are flexion and extension. Flexion is when you bend your knee and the shin bone moves towards the buttock. Knee extension is when you straighten out your knee. The extension is the opposite of flexion. PT, trainers, and physicians alike measure the degree of knee flexion and extension. When lying flat on an examination table or hard surface your knee should be able to extend so that there is no angle between the thigh and shin bone. The inability to straighten the knee is also known as an extension lag and is a reason for concern.

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Knee Buckling

Knees can buckle, causing a sensation of one or both knees giving out that affects nearly 17% of adults. The knees are regarded to be one of the most essential (and biggest) joints in the human body because they play significant roles in basic activities such as walking and sitting. When our knees begin to feel unstable, weak, or begin giving out, it is easy to become stressed since we rely so heavily on them for movement. The knee can become stable from numerous types of injuries. The knee is kept stable by the following structures: Tendons attach the leg muscles…

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Knee Hurts When I Bend It and Straighten It

Your knees bend countless times throughout the day. Running up the stairs, down the hall after kids, and getting into the car. You straighten the knee as you walk, descend stairs or get into and out of the car. Bending and straightening the knee are necessary for daily activities. Knee pain with bending or straightening may be a mild, transient irritation or may indicate a more significant problem. Learn more below and avoid further injury and dysfunction. Knee pain can vary significantly depending upon many factors including the actual source of the pain, the severity of the injury, general health, and level of activity…

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Knee Hyperextension

The knee is a hinge joint between the femur and the tibia along with an accessory bone, the fibula. These bones are held together via ligaments that keep the bones aligned while the joint goes through its natural range of motion. These ligaments are: Medial Collateral Ligament (MCL), Lateral Collateral Ligament (LCL), Anterior Cruciate Ligament (ACL), Posterior Cruciate Ligament (PCL). from zero degrees fully extended to 140 degrees fully flexed. BUT when a force from the front to the back overcomes the strength of the ligaments the knee is forced into an unnatural position called “Hyperextension” which, in turn, can…

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Knee Pain

Knee pain can be caused by many factors. Overuse injuries, direct trauma to the knee and arthritis are the most common causes of knee pain. Damage to the knee structures may cause swelling, scar tissue formation (fibrosis), and loss of function of the joint. Pain is often accompanied by difficulty walking, weakness, and instability. When the knee is overused, the thigh and shin bones (femur and tibia), cartilage, or tendons may experience stress. This leads to pain and discomfort as well as stiffness in the knee. Overuse injuries are common among athletes who participate in sports that involve running, jumping…

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Knee Popping

Knee popping can be a sensation that something is moving around in the knee. There may also be an audible sound associated with the popping, which in medical terms is called crepitus. This can also cause what we call mechanical catching or locking, which may make the knee feel like it is stuck in an extended or flexed position, and you have to move it in certain ways to get out of that. This knee popping sensation or sound or could be a very simple issue or it could be a sign that more serious damage is going on in the knee, so determining what is causing it is very important. So, the knees may pop and get in a certain position….

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Knee Swelling

Swelling of the knee, also known as water on the knee, is a condition in which fluid collects around the knee joint. Swelling can occur for a variety of reasons and affect patients of any age. Some swelling can be treated with over-the-counter medicines, but persistent and continuous swelling might result in tissue damage, bone softening, and cartilage deterioration. Over-the-counter medicines will assist relieve pain for individuals with a history of osteoarthritis and swelling following physical activity, such as exercise or running. During and after activity, the patient may apply compression sleeves to reduce the inflammation. Ice is another method…

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Loud Pop in Knee followed by Pain

If you hear a loud pop in your knee and then experience pain, it is possible that you have torn a ligament. Ligaments are the bands of tissue that connect bones to other bones and help stabilize the joint. There are four main ligaments in the knee: the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), and lateral collateral ligament (LCL). The ACL is the most commonly injured ligament in the knee. It runs diagonally across the front of the knee and is responsible for rotational stability. A tear in the ACL can cause severe pain, swelling, and instability in the knee….

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Reduced Range of Motion in Knees

A knee can feel stiff if there is some swelling in or around the joint or muscle tightness can caused restricted motion This can occur from a problem in the knee joint, such as inflammation, arthritis, or infection, or an injury. The distance and direction that a joint may move are referred to as its range of motion. Various joints in the human body have specific normal ranges set by doctors and therpists. One study, for example, found that a normal knee should be able to bend to between 133 and 153 degrees. A typical knee should also be able to extend fully straight. Limitation of motion occurs when a person range of motion in any limb is reduced below the normal range….

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Tightness in Knee

What could tightness in your knee mean? When fluid builds up inside the knee as a result of an injury, overuse, or medical problem, the knees become swollen and tight. Swelling might be mild, so you may not always notice it unless it is serious damage. You may feel this as stiffness in the knee since swelling may not be visible. Swelling restricts movement since there is less room in the knee. Fluid buildup can be caused by irritation, internal bleeding, and injuries to the knee. Arthritis, gout, tumors, and baker cysts are all causes of swelling. Pain and swelling are the responses of your body to damage. Together they can lead to stiffness in your knee…

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Weak in Knees

Weakness in the knee can be a symptom of many different knee conditions. Some of the most common causes of weakness in the knee include ligament tears, meniscus tears, and arthritis. Another important but often overlooked cause of knee weakness is irritation or injury of the nerves in the low back. If you are experiencing any type of weakness in your knee for long durations of time (3 weeks), it is important to see a doctor to determine the cause. Some of the most common symptoms of knee weakness include difficulty standing up from a seated position, difficulty walking, climbing or descending stairs…

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Treatment Options for ACL Tears

ACL reconstruction has become a standard of care for most ACL tears because the spontaneous healing rate of ACLs is less than 5% (1). But at The Centeno-Schultz Clinic, we have created a novel treatment for ACL tears to prevent the need for a knee ligament surgery!  Utilizing your own body’s bone marrow concentrate (containing stem cells), we can harvest and concentrate the cells, then precisely inject them into the injured ligament. This injection of your own healing cells allows your body to regenerate the ligament and effectively prevents the need for knee ligament surgery!  We have published multiple peer-reviewed research papers demonstrating 7 to 8 out of 10 patients with an ACL tear can avoid the need for knee ligament surgery!

Knee Ligament Surgery

Knee ligament surgeries have become quite common, ACL (anterior cruciate ligament) surgeries average 250,000+ surgeries alone every year! These invasive surgeries have come under investigation in recent years, wondering the necessity, or need to be done. Your knee has 3 points of contact or compartments that house the cartilage of your knee: the patella-femoral compartment, lateral (outside) compartment, medial (inside) compartment. These compartments are held together by a network of ligaments that hold each bone together and allow the knee to move properly. The main knee ligament surgery…

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NSAIDs

The other day I was evaluating a patient and reviewing the treatment options for their spine condition.  After discussing prior treatments, we got to the topic of medications taken for pain relief. She explained that she mainly utilized anti-inflammatory (NSAID) medications and then she told me to hold much she takes and has been for many years…..she takes close to 2 grams (2000 milligrams) on a daily basis which equated to about 9-10 capsules of medication per day.  I was shocked, considering she was pre-diabetic and with high blood pressure plus the kicker of it is that her PCP (primary care physician) is ok with this…

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PRP for ACL Tears & Sprains

The ACL is one of the main ligaments of the knee. Its most important role is to prevent your tibia (shin bone) from moving forward on your femur (thigh bone). ACL injuries commonly occur when you twist or rotate while running, planting, and stopping suddenly or landing hard on your leg after a jump. However, sometimes people without any of these factors involved will also get this injury. Athletes are at high risk for ACL tears because they often play sports that require quick starts, stops, and jumps. If you tear your anterior cruciate ligament (ACL), it usually means surgery…

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PRP Knee Injections

PRP stands for Platelet-Rich Plasma. Platelets are blood cells that prevent bleeding. They contain important growth factors that aid in healing. Plasma is the light yellow liquid portion of our blood. So PRP is simply a concentration of a patient’s own platelets that are suspended in plasma and are used to accelerate healing. PRP is NOT stem cell therapy. Regrettably, blood contains few circulating stem cells. Rich sources of stem cells are bone marrow and fat. PRP is rich in growth factors. There are many different types of growth factors with different properties. VEGF is a very important one as it can increase the blood flow to an area.

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Doctors That Assist with ACL Tears & Sprains

Christopher J. Centeno, MD

Christopher J. Centeno, M.D. is an international expert and specialist in Interventional Orthopedics and the clinical use of bone marrow concentrate in orthopedics. He is board-certified in physical medicine and rehabilitation with a subspecialty of pain medicine through The American Board of Physical Medicine and Rehabilitation. Dr. Centeno is one of the few physicians in the world with extensive experience in the culture expansion of and clinical use of adult bone marrow concentrate to treat orthopedic injuries. His clinic incorporates a variety of revolutionary pain management techniques to bring its broad patient base relief and results. Dr. Centeno treats patients from all over the US who…

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John Schultz, MD

My passion and specialization are in the evaluation and treatment of cervical disc, facet, ligament and nerve pain, including the non-surgical treatment of Craniocervical instability (CCI). I quit a successful career in anesthesia and traditional pain management to pursue and advance the use of PRP and bone marrow concentrate for common orthopedic conditions. I have been a patient with severe pain and know firsthand the limitations of traditional orthopedic surgery. I am a co-founder of the Centeno-Schultz Clinic which was established in 2005. Being active is a central part of my life as I enjoy time skiing, biking, hiking, sailing with my family and 9 grandchildren.

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John Pitts, M.D.

Dr. Pitts is originally from Chicago, IL but is a medical graduate of Vanderbilt School of Medicine in Nashville, TN. After Vanderbilt, he completed a residency in Physical Medicine and Rehabilitation (PM&R) at Emory University in Atlanta, GA. The focus of PM&R is the restoration of function and quality of life. In residency, he gained much experience in musculoskeletal medicine, rehabilitation, spine, and sports medicine along with some regenerative medicine. He also gained significant experience in fluoroscopically guided spinal procedures and peripheral injections. However, Dr. Pitts wanted to broaden his skills and treatment options beyond the current typical standards of care.

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Jason Markle, D.O.

Post-residency, Dr. Markle was selected to the Interventional Orthopedic Fellowship program at the Centeno-Schultz Clinic. During his fellowship, he gained significant experience in the new field of Interventional Orthopedics and regenerative medicine, honing his skills in advanced injection techniques into the spine and joints treating patients with autologous, bone marrow concentrate and platelet solutions. Dr. Markle then accepted a full-time attending physician position at the Centeno-Schultz Clinic, where he both treats patients and trains Interventional Orthopedics fellows. Dr. Markle is an active member of the Interventional Orthopedic Foundation and serves as a course instructor, where he trains physicians from around the world.

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Matthew William Hyzy, D.O.

Doctor Hyzy is Board Certified in Physical Medicine and Rehabilitation (Physiatry) and fellowship-trained in Interventional Orthopedics and Spine. Dr. Hyzy is also clinical faculty at the University of Colorado School of Medicine in the Department of Physical Medicine and Rehabilitation; In addition, Dr. Hyzy is an Adjunct Clinical Assistant Professor at The Rocky Vista University College of Osteopathic Medicine. Dr. Hyzy also maintains an active hospital-based practice at Swedish Medical Center and Sky Ridge Medical Center. He is also recognized and qualified as an expert physician witness for medical-legal cases and Life Care Planning. He is published in the use of autologous solutions including…

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Brandon T. Money, D.O., M.S.

Dr. Money is an Indiana native who now proudly calls Colorado home. He attended medical school at Kansas City University and then returned to Indiana to complete a Physical Medicine and Rehabilitation residency program at Indiana University, where he was trained on non-surgical methods to improve health and function as well as rehabilitative care following trauma, stroke, spinal cord injury, brain injury, etc. Dr. Money has been following the ideology behind Centeno-Schultz Clinic and Regenexx since he was in medical school, as he believed there had to be a better way to care for patients than the status quo. The human body has incredible healing capabilities…

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Mairin Jerome, MD

Mairin Jerome, MD

Dr. Mairin Jerome is a physiatrist with subspecialty fellowship training in Interventional Orthopedics and Regenerative Medicine. This subspecialty serves to fill the gap for patients who are interested in therapeutic options that lie between conservative treatment and surgery. Dr. Jerome uses regenerative medicine techniques, including prolotherapy and orthobiologics, via X-ray or ultrasound guidance to precisely deliver injections to areas of musculoskeletal injury or degeneration. Orthobiologics refers to tissue harvested typically from a person’s own body, such as platelets (platelet-rich plasma, PRP) or bone marrow, for use in treating painful musculoskeletal conditions. The goal is to stimulate the body’s healing mechanisms to improve pain, function, and decrease inflammation.

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Other Resources for ACL Tears & Sprains

Free Download: The Knee Owner’s Manual

This e-book by Dr. Chris Centeno examines the knee and its role in the human musculoskeletal system and the body as a whole. The Knee Owner’s Manual provides a series of tests and clearly defined exercises that you can perform on your own to assess and monitor your own knee health. It will allow you to look for trouble spots where your own body may be having difficulty with stability, articulation, symmetry, and neuromuscular function. You’ll be able to see how these deficits in other regions of the body relate to the knee.

The Knee Owner’s Manual also discusses how Regenexx is pioneering the development of interventional orthopedics, a new branch of medicine that employs regenerative biologic therapies such as adult bone marrow concentrate and platelet-rich plasma to help repair and strengthen damaged tissues in other areas of the body.

This is contrasted with invasive knee surgeries, which often remove important tissues or replace the entire knee itself when it becomes damaged. With hyperlinks to more detailed information, related studies, and commentary, this book condenses a vast amount of data, images, and resources into an enjoyable and informative read. This is the first edition of The Knee Owner’s Manual, a companion book to Orthopedics 2.0.

  • How Likely Is a Second ACL Tear On the Same Knee?

    Anterior Cruciate Ligament Injuries and Treatments The ACL (anterior cruciate ligament) is an important knee stabilizing ligament. It prevents the tibia from moving too much frontward (anterior translation) and twisting too much (internal rotation).  It is under most stress with landing from a jump, or a planted foot with twisting, and this is how it … Continued


  • Regenexx ACL Repair vs Reconstruction Surgery for Knee ACL

    Regenexx ACL Repair vs Reconstruction Surgery for Knee ACL Today I’d like to highlight a patient named Joe’s story.  Joe is unique in that he has had the non-surgical Regenexx Perc-ACLR procedure which uses your own cells injected via a small needle, and a surgical ACL reconstruction, so he can compare the two. So let’s … Continued


  • ACL Tear Treatment Without Surgery: The Truth You Need to Know!

    The Anterior Cruciate Ligament (ACL) is a key stabilizer in the knee that is frequently injured. Dr. Schultz discusses what an ACL is, the major causes of tears, symptoms associated with a tear, what ACL surgery is, its risk, and effective ACL tear treatment without surgery. He shares a recent clinical success with a 14y/o soccer player who avoided ACL surgery by using her own stem cells at the Centeno-Schultz Clinic.


  • ACL MRI Evidence for the Perc-ACLR

    Dr. Centeno goes through 23 examples of ACL MRI that show the superiority of the Regenexx Perc-ACLR.  Transcript Hi, it’s Dr. Centeno. And today we’re going to go over MRI evidence that the Regenexx Perc-ACLR procedure heals ACL tears. So, we invented ACL stem cell injections at the Centeno-Schultz Clinic, which is the headquarters of … Continued


  • How to Tell if You Tore Your ACL?

    Knee pain can stop you in your tracks, and a common cause of knee pain and instability is an ACL tear.  What is an ACL?  What causes an ACL to tear?  How to tell if you tore your ACL?  What are the signs and symptoms of an ACL tear? Can you still walk if you … Continued


  • ACL Stem Cell Treatment Cost: How to Get What You Pay For

    Knee pain can happen suddenly making simple steps almost impossible.  What is the ACL?  Is ACL surgery a major surgery?   How much does ACL Stem Cell Treatment Cost?  Is there a nonsurgical alternative to treat ACL tears?  Let’s dig in. What is the ACL? Ligaments are thick bands of connective tissue that connect one bone … Continued


References:

  1. Razi M, Soufali AP, Ziabari EZ, Dadgostar H, Askari A, Arasteh P. Treatment of Concomitant ACL and MCL Injuries: Spontaneous Healing of Complete ACL and MCL Tears [published online ahead of print, 2020 Apr 8]. J Knee Surg. 2020;10.1055/s-0040-1708858. doi:10.1055/s-0040-1708858

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