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Arthritis in Knee? Here’s What to Know

| | Knee, Knee Osteoarthritis
knee arthritis

Every day we evaluate patients who have been seen by an orthopedic surgeon and have been told they need a total joint replacement. These surgeries require long recoveries and risk major complications so naturally, patients are looking for an alternative to allow them to return to their active lives without the need for such invasive procedures! By 2030, total knee replacement surgeries are projected to grow 673% to 3.5 million procedures per year, with the number one indication for total knee replacements being arthritis in the knee.

So let’s jump into the topic of knee arthritis…..what is it.…and what can be done to treat it without replacing the knee?

What Is Knee Arthritis?

In the human body, a joint is simply where 2 ends of bone come together. At the ends of these bones, there is a thick substance called “Hyaline Cartilage” that lines the ends.  Hyaline cartilage is extremely slippery which allows the two ends of the bone to slide on top of each other.  Then there is a capsule that connects the two ends filled with “synovial fluid” that acts as a further lubricant to make it more slippery!

Arthritis in the knee is defined by loss of the hyaline cartilage plus other changes that happen to the bone such as additional bone being laid down (bone spurs/osteophytes). The cartilage layer is worn down to the point of exposing the underlying bone they cover, with the severity of wear to the cartilage = the stage of arthritis.

Historically the classification is based on an X-ray, which categorizes the cartilage loss by the joint space loss. X-rays cannot see cartilage but the space between the bones can give us an idea of the health of your cartilage.

Symptoms Related to Knee Arthritis

Did you know that MRI or X-ray findings consistent with arthritis in knee are common in anyone over the age of 40 EVEN in individuals with zero knee pain or asymptomatic knees (1-3)? This means there are other causes of knee pain other than just arthritis. This highlights the importance of a detailed examination and getting a thorough history of the issues to help determine if the pain is from the knee arthritis OR the knee arthritis is asymptomatic, and the pain is coming from something other than the cartilage loss!

Common complaints about most knee conditions (including arthritis in knee) are:

Pain Increasing Gradually During Activities

If you have a loss of cartilage and underlying bone is exposed, additional stress on the knee leads to bone bruising, which can be seen on an MRI as “bone marrow edema.” Research has shown a high association with arthritis pain when paired with a bone bruise.


Increased fluid in the knee is not a universal sign of arthritis as many things can cause fluid to build up in the knee and it’s important to investigate further to determine the source! Some examples are:

  • Meniscus tears – Diagnostic ultrasound can identify meniscal tears as can MRIs. In the absence of other conditions these may be a cause of fuid buildup.
  • Ligament injuries such as ACL or PCL tears – Fluid in the joint is not synovial fluid with ligament tears but bleeding in the joint which can also be seen in fractures.
  • Arthritis – There are many different autoimmune diseases that increase joint fluid, as well as osteoarthritis in which cartilage loss causes thinning of the synovial fluid and it expands creating excessive fluid in the joint.
  • Joint infections can cause excessive swelling.

For an accurate diagnosis of what kind of fluid is building up, aspirating the fluid and sending it to the lab for more detailed analysis is needed!

Crackling Sound

With knee arthritis, additional bone exists in the form of bone spurs. These can rub on other bones or

Crackling can happen in a 100% normal knee where some air or fluid release occurs or a ligament or tendon is snapping over a bony prominence.

One potential issue that can cause the crackling sound is lax ligaments surrounding the knee such as the medial (inside) or lateral (outside) ligaments.

Check out what a live diagnostic ultrasound of laxity in the MCL (Medial collateral ligament) looks like below. This laxity allows additional movement in the joint which can lead to “crackling or popping” sounds in the joint

Buckling And Locking

With knee arthritis, bone bruises or bone spurs can cause immediate and intense shots of pain which can inhibit all the muscles around the joint. This can manifest itself in the knee giving out or locking in place.

BUT ligament injuries such as an ACL tear can also cause incidences of buckling as the ligament is not functioning enough to support the knee.

Meniscus tears or loose bodies in the joints can get stuck between the bones and create locking issues as well!

Limited Range Of Motion

Bone spurs grow all around the joint with arthritis which can impede the joint from a full range of motion.

So, as you can see, there are a lot of overlap symptoms between knee arthritis and other conditions in the knee, which highlights the importance of a highly trained medical provider investing the time to discuss your issues, examine your knee, and ordering an appropriate test to best determine the cause of your unique knee pain.  All too often a patient goes to a doctor and in 5 mins the doctor tells the patient what is wrong without ever talking to the patient or examining them – just going off an MRI or x-ray.

Common Causes of Knee Arthritis

Developing arthritis in knee or any other joint in your body is, unfortunately, inevitable.  If you live long enough, one of your joints will likely break down and develop arthritis.  Some individuals develop arthritis sooner than others. There are many risk factors that determine whether this happens to you!  Some you can control while others are predetermined. Let’s dig in….


You cannot control what genes you are born with and some genes place you at risk for developing arthritis prematurely.


Risk for multiple types of arthritis increase with age. Those include:

  • Osteoarthritis
  • Rheumatoid Arthritis
  • Gout


The relationship between excess weight and OA is well established. In fact, obesity appears to be the top modifiable factor that influences OA risk, with one study reporting that individuals whose body mass index (BMI) was higher than 30 kg/m2 had a nearly 7-fold increased risk of developing knee OA. (5)

Repetitive Stress Injuries

Small repetitive traumas over time increase the cumulative damage in the knee and eventually accumulate irreversible damage. Have you ever seen the knees of NFL players, especially a lineman after years of weighing >300lbs and repetitive stress (6)?

Past Surgeries

Especially ACL reconstruction and meniscectomy, develop post-traumatic knee arthritis as a complication of both the trauma that resulted in the injury as well as trauma from the surgery.

New research shows ACL reconstruction surgery itself leads to a greater risk of developing knee arthritis! To read more go here:

Common Treatments for Knee Arthritis

Knee arthritis treatment, like most other orthopedic treatment, ranges from the least invasive to the most invasive treatments. They begin with something as simple such as medications and physical therapy to the most invasive such as total knee replacements….and many treatments in between.


Therapies / Modalities

Physical Therapy

One of the main treatments to prevent arthritis with the goal to correct the underlying bio-mechanics by strengthening the knee and the muscles up and down the kinetic chain. Physical therapy has been proven a useful toll with the right therapist to help both pain and function!

Simple Injections

If physical therapy is not helping, most physicians or orthopedic physicians resort to knee injections.

Cortico-Steroid Injections

Steroids have been a mainstay in the treatment of arthritic conditions. But there are downsides and risks to these injections:

  • Systemic effects such as increasing cortisol and elevating blood sugars
  • Risk of creating avascular necrosis
  • Risk of degenerating the joint more and advancing arthritis (which is the wrong direction if already have arthritis!)

Hyaluronic Acid (HA) Injection

This substance is naturally found in the synovium and synovial fluid so injection provide nutrition to the joint and lubrication and can give lasting improvement 6 to 12 months.

Other Alternative Therapies

Alternative therapies include acupuncture, dry needling, cupping, Graston, and blood flow restriction therapy.

Surgical Procedures

There are multiple surgical procedures that are performed for arthritis in the knee.

Knee arthroscopic procedure “clean out”

Surgeons take you to the surgical suite, place a camera inside the knee and shave down loose bits of cartilage floating around as well as trim meniscus. BUT long term evidence and research have proven that this method does more harm than good (7).

Supported by landmark articles by Mousley et al. and Kirkley et al., it may seem that the role of arthroscopic surgery in the degenerative knee is no longer justified. They found no difference in outcomes in Mousley ‘s single-blinded randomized controlled trial in 2002 comparing arthroscopic surgery versus sham surgery and again no difference in outcomes in Kirkley’s randomized controlled trial in 2008 comparing arthroscopic surgery versus optimized medical and physical therapy. This makes total sense given the fact they are shaving away the cartilage you have left that we know won’t grow back…….who thought that was a good idea, to begin with?!

Total Joint Replacement

To learn more about TKR (Total Knee Replacement) go here:

Using Support / Brace

Bracing can help support the joint when ligaments around and in the joint aren’t up to the task and offload the arthritis region of the joint assuming only one of the 3 compartments showing arthritic changes.

Alternative Treatments To Surgery For Knee Arthritis

All of the physicians at Centeno Schultz Clinic have been researching and continue to search for better alternatives to total joint replacement to give our patients a less invasive alternative that accomplishes the goal of getting patients back doing what they want to do with little downtime, less risk of complications and that last as long a replacement!

Research has shown that using your own Bone Marrow Concentrate (which contains stem cells) can be just as effective with less risk when directly compared to total joint replacement.


  • Anesthesia related to the TKA side was longer than for the cell therapy group. Medical and surgical complications were more frequent after TKA.
    • A higher number of thrombophlebitis was observed on the side with TKA (15%) versus none on the side with cell therapy (0%).
    • At follow-up (average of 12 years, range 8 to 16 years), six (out of 30) TKA knees needed subsequent surgery versus only one with cell therapy.
    • The Knee Score had improved and remained similar in the TKA and cell therapy groups (respectively 80.3 points ± 11 versus 78.3 ± 23);
    • 21 patients preferred the knee with cell therapy and 9 preferred the knee with TKA.
    • Knees with cell therapy had improvement on cartilage and bone marrow lesions observed at the site of bone marrow subchondral injection.

Examining And Diagnosing Knee Arthritis

If you made it this far, congrats! We have been treating knee arthritis with advanced regenerative interventional orthopedic technology since the early 2000s. We were the first physicians in the country to use the patient’s own Bone Marrow Concentrate containing stem cells to treat various orthopedic conditions. With decades of experience to lean on, we know how to get our patients the best outcomes possible: it’s all about the details!  With our examinations, we take 60 mins of physician-patient face-to-face time to get a detailed history of the knee pain, a thorough examination of how your knee uniquely works, and utilize diagnostic ultrasound to evaluate the soft tissue surrounding the joint. We also take a very thorough look at your imaging, not just read the report.

Based on all of the above we come up with a comprehensive evaluation, and along with all our data and current research, we determine a Candidacy Rating of Good, Fair, or Poor. Candidacy is our expert opinion on the likelihood of success, and which therapy will yield the best long-term outcome to accomplish your goal.  Many times after a full examination we do not recommend any of our treatments and recommend a surgical consultation. We will be honest with you in our evaluation once we have all the evidence!

What You Can Do To Prevent Knee Arthritis 

There are always things you can do to be proactive in preventing knee arthritis or stopping or slowing the progression of OA!

Get Yourself Checked To Get A Better Diagnosis

If you are considering an alternative to knee replacement and would like to get a detailed evaluation, contact our office! We do both in-patient examinations and telehealth consultation to help give you an accurate diagnosis and a candidacy rating on how effective, or whether it’s even indicated, a Regenexx Procedure for knees would likely be for you!


  1. Beattie KA, Boulos P, Pui M, O’Neill J, Inglis D, Webber CE, Adachi JD. Abnormalities identified in the knees of asymptomatic volunteers using peripheral magnetic resonance imaging. Osteoarthritis Cartilage. 2005 Mar;13(3):181-6. doi: 10.1016/j.joca.2004.11.001. PMID: 15727883.
  2. Pappas GP, Vogelsong MA, Staroswiecki E, Gold GE, Safran MR. Magnetic Resonance Imaging of Asymptomatic Knees in Collegiate Basketball Players: The Effect of One Season of Play. Clin J Sport Med. 2016;26(6):483-489. doi:10.1097/JSM.0000000000000283
  3. Guymer E, Baranyay F, Wluka AE, Hanna F, Bell RJ, Davis SR, Wang Y, Cicuttini FM. A study of the prevalence and associations of subchondral bone marrow lesions in the knees of healthy, middle-aged women. Osteoarthritis Cartilage. 2007 Dec;15(12):1437-42. doi: 10.1016/j.joca.2007.04.010. Epub 2007 Jun 7. PMID: 17560134.
  4. Culvenor AG, Øiestad BE, Hart HF, Stefanik JJ, Guermazi A, Crossley KM. Prevalence of knee osteoarthritis features on magnetic resonance imaging in asymptomatic uninjured adults: a systematic review and meta-analysis. Br J Sports Med. 2019;53(20):1268-1278. doi:10.1136/bjsports-2018-099257.
  5. King LK, March L, Anandacoomarasamy A. Obesity & osteoarthritis. Indian J Med Res. 2013; 138(2): 185–193.
  6. Davies MAM, Kerr ZY, DeFreese JD, Arden NK, Marshall SW, Guskiewicz KM, Padua DA, Pietrosimone B. Prevalence of and Risk Factors for Total Hip and Knee Replacement in Retired National Football League Athletes. Am J Sports Med. 2019 Oct;47(12):2863-2870. doi: 10.1177/0363546519870804. Epub 2019 Sep 9. PMID: 31498654.
  7. Law GW, Lee JK, Soong J, Lim JWS, Zhang KT, Tan AHC. Arthroscopic debridement of the degenerative knee – Is there still a role?. Asia Pac J Sports Med Arthrosc Rehabil Technol. 2018;15:23-28. Published 2018 Dec 8. doi:10.1016/j.asmart.2018.11.003


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