Therapeutic knee injections are a treatment that directly delivers medicine to the knee joint. They are often used to alleviate painful symptoms caused by knee arthritis. Several injection options are available to relieve knee pain, including corticosteroids, hyaluronic acid (viscosupplementation), platelet-rich plasma (PRP), dextrose prolotherapy, and saline prolotherapy. The type of knee pain, its cause, and other factors, such as age and medications being taken, are all considered to determine which injection best suits the patient.
Although knee injections are generally safe, there is a possibility of experiencing some side effects after the infusion. However, the risk of complications is low. It is essential to discuss the different knee injection options with your healthcare provider—including the possible side effects—as you consider the most appropriate treatment plan for you.
What are knee gel injections?
Knee gel injections, also known as viscosupplementation, involve injecting a gel-like substance, typically made from hyaluronic acid, into the knee joint. This procedure aims to provide lubrication and cushioning to the joint, reducing pain and improving mobility for individuals suffering from osteoarthritis or knee joint issues. The gel mimics the natural synovial fluid in the knee, helping to alleviate discomfort and improve joint function.
Types of Injections for Knee Pain
Cortisone Injections
Cortisone injections are often recommended for individuals who suffer from pain and swelling due to knee arthritis. These injections can be highly effective in treating knee pain and osteoarthritis symptoms. The injection provides quick relief from the symptoms, often within 1-3 days. The improvement in symptom relief and pain reduction, measured using VAS (visual analog scores) on a scale of 1-10, typically improves significantly within the first six weeks after the injection. However, the effectiveness of the injection may begin to decline around the 12-week mark after the injection.
If your symptoms return, these injections can be repeated as often as every 3 to 4 months. However, we usually suggest waiting until the pain or swelling symptoms return before getting another injection. Giving the injections too frequently or as a preventive measure can reduce their effectiveness over time, making them less effective in the long run.
Gel Injections
You may have also heard of “Gel” injections. These viscoelastic supplement injections are a hyaluronic acid derivative, a naturally occurring chemical in the normal synovial (joint) fluid.
As we age, the level of hyaluronic acid in our bodies decreases naturally. This substance is responsible for binding to the cartilage surface of our joints and acts as a cushion.
When there is less hyaluronic acid and less cartilage in our knees, it can lead to increased pain. Gel injections are designed to reintroduce this substance into the knee joint to improve cushioning and reduce pain.
These injections are usually suggested as an alternative to cortisone injections and can be administered every six months. Medicare covers them every six months; different insurance companies protect them at varying intervals. These injections are generally not issued on the same day as cortisone injections but can be spaced out a few weeks later to help extend their effects.
Common Use
A corticosteroid injection may quickly decrease inflammation, delivering knee pain relief that lasts two to three months and is periodically prolonged. The temporary pain relief may provide an opportunity to engage in physical therapy, attend a significant life event, or postpone knee replacement surgery.
Before receiving a cortisone injection, the skin around the injection site will be thoroughly cleaned to ensure hygiene and minimize the risk of infection.
Your healthcare provider may use a local anesthetic to numb the injection site. In some cases, an ultrasound may guide the needle placement accurately. The medication is then injected directly into the knee at the site where the needle is inserted.
Knee Gel Injections Side Effects
Pain and Swelling
After the injection, some individuals may experience increased pain and swelling around the knee joint. This could be due to the injection itself or a reaction to the gel substance. It usually subsides within a few days but can sometimes persist for more extended periods.
Infection Risk
Any interfering method carries a chance of infection. Although knee gel injections are generally safe, there is a slight possibility of infection at the injection site. Signs of infection include increased redness, warmth, severe pain, and fever. Quick medical attention is required if these symptoms arise.
Allergic Reactions
Some people might be allergic to the components of the gel. Allergic reactions can range from mild itching and rash to more severe symptoms like difficulty breathing chest tightness, or anaphylaxis. While rare, these reactions require immediate medical intervention.
Joint Stiffness or Limited Mobility
Following the injection, some individuals might experience temporary stiffness or limited range of motion in the knee joint. This usually resolves on its own within a few days, but in rare cases, it may persist or worsen.
Other Complications
Though uncommon, other potential complications might include bleeding, nerve damage, or increased pressure within the joint. These rare complications could cause prolonged discomfort or require additional medical attention.
Always consult with a healthcare professional before undergoing any medical procedure to understand the potential risks and benefits specific to your situation.
Most side effects are temporary and will disappear over time. However, if they persist or worsen, seek medical attention.
Which Type of Knee Injection is Right for Me?
The cortisone injections are more effective for patients experiencing severe pain and acute swelling as they take effect quickly.
The gel injections take effect slowly and can take 4-6 weeks to have their full effect. Therefore, it’s recommended to provide them when the patient suffers more from dull, achy pain and not acute swelling. We often give a cortisone injection to decrease pain and swelling in those settings.
If the symptoms persist for 2 to 4 weeks and you experience dull, achy pain, a gel injection can be administered to prolong the effects. In some studies, these injections have shown a trend of improvement in decreased VAS scores, which can begin 4 to 6 weeks after injection and last for 3 to 6 months.
Conclusion
While knee gel injections offer effective relief for joint pain, they may present potential side effects, including swelling, pain at the injection site, allergic reactions, or infection. While these occurrences are relatively rare, individuals considering this treatment should discuss potential risks with their healthcare provider to make an informed decision about their knee health management.
