Cortisone Injections for Joints:  How Effective are They?

December 8, 2023

Most people know someone who has received a cortisone injection for joint or back pain from injury or inflammation.  Cortisone is a synthetic steroid drug commonly used to decrease inflammation in various conditions from arthritic pain to asthma.  Athletes are often given cortisone injections for musculoskeletal injuries and pain. In fact, studies have shown an absolute risk of having a knee replacement after cortisone injection increases 9.4%.

In 1948, cortisone was discovered to have anti-rheumatic properties and was first used to decrease pain of rheumatoid arthritis.  Soon after this discovery, cortisone injections were commonly administered into inflamed joints, tendons and other areas of pain throughout the body.  By 1960, toxic effects of chronic corticosteroid administration had been described.

Are cortisone injections as beneficial as people are led to believe?  How effective are they?  Are there risks?

Cortisone and Healing: Pain Relief at A Cost?

Cortisone injections come with a big promise of pain relief; one quick shot and you could be all fixed.  Just because your pain is relieved, does it mean you are healed?  Does it have a downside?

Similar to receiving a pharmaceutical drug to treat a symptom rather than treat the underlying cause of that symptom, cortisone injections work like a band-aid, only to mask the pain.

Cortisone not only does not repair the underlying problem; it interferes with the natural healing process of the body.  

For example, you twist your ankle.  The ligaments are overstretched or torn within the ankle and the body’s natural healing process begins.  Cells are released from the tissues to recruit stem cells, healing factors and blood flow resulting in swelling of the ankle.  The injured area begins to heal and remodel.

When cortisone is injected into the area, the healing process is disrupted by cortisone as it shuts down the release of healing factors.  Cortisone reduces swelling and pain, but this swelling is the migration of healing factors to repair the injury.  When you decrease the swelling, you inhibit the natural healing process.  Your pain may be gone, but at a price.

An example using the healing inhibition process from cortisone injections for a good use is cortisone injected for keloid scars.  Cortisone was found to cause scars to regress through the following mechanisms:

  • Suppressing the immune system by inhibiting certain immune cells to migrate
  • Reducing oxygen and nutrients due to constriction of blood vessels
  • Inhibiting skin cells (keratinocytes) and cells that form connective tissue (fibroblasts), slowing collagen formation

These mechanisms do not promote healing for joints! These mechanisms shut down natural healing!

If cortisone shuts down the natural process of healing, injured weakened tissue stays in that state for a longer period of time even though pain may be reduced.  This can predispose you to an increase in repeat injury as not only the length of time of healing has increased, but also your pain is reduced leading you to believe your injury is better as you continue to use the damaged or injured site.

The short-term pain relief of cortisone may come with a long-term price tag.  For example, in the case of cortisone injection for tennis elbow, a study in 2018 was published showing cortisone injection for tennis elbow may produce pain relief up to 6 weeks but leave patients with even worse pain and “actually demonstrate net harm” after 3-6 months.

Cortisone, Collagen, Cartilage and Repeated Injection   

As discussed in Are There Benefits to Collagen Supplements?, collagen makes up about 25-40% of protein in the body, supporting many processes, especially wound healing, joint, ligament and tendon function.  Cortisone injections can disrupt these collagen fibers weakening the ligaments, tendons, and joint mechanics.

Many patients often have repeated cortisone injections for recurrent pain after several months.  A Medline database reviewing 50 articles including 12 human studies and 36 animal studies showed:

  • repeated cortisone injections not only delay the healing process but may weaken collagen, cartilage and
  • can lead to deterioration of the joint with “significant decrease in mechanical properties of the joint.”

This is the very reason doctors limit the amount of cortisone injections to 3 a year.

A 2022 meta-analysis compared patients who received 2-8 recurrent intra-articular corticosteroid injections (AICI) to other injectables (hyaluronic acid, platelet-rich plasma), placebo or no treatment.

  • There were greater improvements in function, pain and quality of life at 3-24 months for those who received other injectables versus cortisone injection.
  • Those who received recurrent cortisone injection exhibited no benefits in function or pain over placebo at 12-24 months.
  • The authors conclude, at 3 months and beyond, recurrent cortisone injections resulted in inferior symptom relief compared with other injectables, including placebo.

A 2013 randomized controlled trial was conducted to compare outcomes from cortisone injection, placebo injection, cortisone injection plus physical therapy, and placebo injection plus physical therapy.  The results showed:

  • Cortisone injection resulted in lower complete recovery and lower improvement versus placebo injection at 1 year.
  • The cortisone injection group had a greater 1-year recurrence.
  • Physical therapy versus no physical therapy groups did not differ much for complete recovery or much improvement.
  • Cortisone versus placebo injection at 26 weeks, showed the cortisone injection group had lower complete recovery and lower improvement.
  • The conclusion is patients who received cortisone injection resulted in worse clinical outcomes compared to placebo at 1 year.

A 2017 randomized clinical trial evaluated the effect steroid injection versus placebo injection had on pain and cartilage volume in 140 patients with knee osteoarthritis.

  • The cortisone injection group experienced greater cartilage volume loss than placebo, meaning a possible acceleration and progression of osteoarthritis.
  • There was no difference in pain between the two groups.

A 2020 study followed nearly 4,000 patients for 9 years with, or at risk of developing, symptomatic osteoarthritis of the knee to assess whether those who received cortisone injection had a higher risk of requiring knee replacement surgery compared to those who had not received injection.

  • The authors conclude cortisone injections are associated with an increased risk of knee replacement surgery.
  • With each subsequent cortisone injection, the absolute risk of knee replacement increased by 9.4%.

Alternatives to Cortisone Injection   

The best response to healing from injury is to regenerate tissue and promote a healing environment.  Rather than treating symptoms, promoting the healing process and restoring normal function is better long-term.  Giving the healing cells fuel to repair and recruit more healing cells is the foundation of regenerative medicine.

There are various treatment modalities in this realm showing much promise such as acoustic wave therapy, natural biologic injections (PRP, stem cells, amniotic membrane extract, Wharton’s jelly, exosomes), peptides, cold plunges, cryotherapy, red light therapy, and natural hormone therapy.  Clinical trials need to be done on all these therapies.

Biologic injections using Platelet-rich plasma (PRP):

  • A 2021 meta-analysis including 8 studies and 648 patients showed:
    •  there were superior outcomes with PRP injection versus cortisone for knee osteoarthritis at 12 months follow up.
    • Also noted, 3 PRP injections separated by one week was more effective than 1 PRP injection.
  • A 2018 systematic review including 5 randomized controlled trials showed:
    • cortisone injection led to rapid symptomatic improvement at 6-8 weeks before symptom recurrence compared to PRP which led to slower but ongoing symptom improvement up to 104 weeks.
    • Also noted, cortisone injection led to cortical erosion and tendon tear in more patients than PRP.

Acoustic Wave Therapy vs Cortisone Injection in Plantar Fasciitis:

In a 60 patient 2019 study using acoustic wave therapy (EPAT) vs cortisone injection the authors stated the following conclusions:

  • “Extracorporeal pulse-activated therapy is as effective as corticosteroid injection, if not more so, for the treatment of recalcitrant plantar fasciitis and should be considered earlier in the treatment course of plantar fasciitis.”
  • “The VAS score (pain score) was significantly improved with EPAT treatment compared with corticosteroid injection.”

Conclusion

While cortisone injections may offer initial symptomatic pain relief, it does not promote tissue healing and may lead to further damage and prolonged recovery, especially with repeated injections.  This can lead to long term harm of the joint.

Regenerative treatment modalities such as peptides, exosomes, prp, stem cells, acoustic wave therapy show promising benefits as adjuncts to kickstarting and restoring the natural healing process.

Posted in Cortisone Injections, Injections