Uncovering Steroid Injections

July 4, 2024

Explore how a steroid injection in the knee can help manage pain, understand its effectiveness, risks, and more.

Understanding Cortisone Shots

Cortisone shots, also referred to as steroid injections, are a common medical treatment used to address various forms of inflammation and pain, particularly in the joints. These injections can be highly effective in managing symptoms of conditions like arthritis, tendinitis, bursitis, and more.

Purpose and Application

A steroid injection in the knee or other areas serves the purpose of delivering a dose of medication directly to a problem spot in the body. This targeted approach aims to reduce inflammation and alleviate pain, making it beneficial in treating various conditions such as arthritis, tendinitis, or bursitis [1].

Healthcare providers administer these shots to treat inflammation in joints, tendons, or bursae. Bursae are fluid-filled sacs that cushion spaces around and between joints, tendons, and bones. They play a crucial role in reducing friction and facilitating movement, but they can become inflamed and painful in certain conditions [1].

These injections are not limited to large joints. Cortisone shots are often injected into joints such as the ankle, elbow, hip, knee, shoulder, spine, or wrist. They can also be beneficial for smaller joints in the hands or feet. The injection contains a corticosteroid medicine for long-term pain relief and a local anesthetic for immediate pain relief.

Mechanism of Action

Cortisone is a type of corticosteroid, which is a class of drugs that mimic the effects of hormones produced by the adrenal glands. When injected into an inflamed area, the cortisone acts as a powerful anti-inflammatory agent, reducing swelling and pain.

The mechanism by which cortisone shots work is by suppressing the immune system's response to injuries. This helps reduce inflammation and swelling, which in turn reduces pain and improves function. Cortisone shots might be most effective in treating inflammatory arthritis like rheumatoid arthritis and can be part of the treatment for other conditions such as osteoarthritis, bursitis, gout, tendonitis, and more [2].

In summary, cortisone shots play a crucial role in managing pain and inflammation caused by various conditions. By understanding their purpose and mechanism of action, patients can make informed decisions about their use as part of their treatment plan.

Effectiveness and Duration

When it comes to evaluating the performance of a steroid injection in the knee, factors such as individual response and duration of pain relief are crucial.

Individual Responses

The effects of a cortisone shot are usually minimal on the whole body as the injection delivers the corticosteroid directly to the area experiencing inflammation. This localized approach ensures that the majority of the medication targets the inflammation site, thereby reducing the potential for systemic side effects [1].

In terms of effectiveness, high-quality studies have shown promising results. The relative risk for improvement in symptoms of osteoarthritis of the knee at 16-24 weeks after intra-articular corticosteroid injections was 2.09, with a 95% confidence interval of 1.2 to 3.7. This indicates that about 4.4 patients would need to receive treatment to observe an improvement in one patient [3].

Duration of Pain Relief

The duration of effectiveness of a cortisone shot varies among individuals, typically lasting between a few weeks and a few months, depending on the body's response [1].

Research also supports short-term (up to two weeks) improvement in symptoms of osteoarthritis of the knee after intra-articular corticosteroid injection. Significant improvement was also shown in methodologically sound studies addressing longer-term response (16-24 weeks).

However, it's important to note that the duration of pain relief can vary greatly among individuals. Factors such as the severity of the inflammation, the precise location of the injection, and the individual's overall health can all influence how long the effects of the injection last.

In summary, steroid injections in the knee can provide significant relief from pain and inflammation associated with osteoarthritis. However, the duration and extent of this relief can vary, and it's important to discuss these factors with a healthcare professional to ensure that this treatment is the best option for your individual needs.

Risks and Side Effects

While a steroid injection in the knee can provide significant relief from pain and inflammation, it's essential to understand the potential risks and side effects associated with the procedure. These may include a cortisone flare, skin reactions, and metabolic effects.

Cortisone Flare

A cortisone flare is a reaction that can occur when the injected cortisone medication crystallizes inside the body. This can lead to pain and inflammation, which typically lasts for one or two days. A cortisone flare can be treated with rest and cold packs applied to the affected area. This is a relatively common side effect, and patients should be aware of this possibility before receiving a cortisone injection [4].

Skin Reactions

Some patients may experience skin discoloration around the injection site. This reaction may occur a few weeks or months after the injection, affecting 1.3% to 4% of patients, especially those with darker skin tones. Additionally, fat atrophy at the injection site can happen, resulting in a divot or depression in the skin. This is estimated to occur in 0.6% of injections, with skin appearance usually returning to normal within 6 months to 2-3 years.

Metabolic Effects

Cortisone injections can cause metabolic changes in the body, particularly in relation to blood sugar levels. This is an important consideration for diabetic patients, as cortisone injections may raise blood sugar levels, even though the injection doesn't deliver cortisone directly to the bloodstream. This can necessitate adjustments in diabetes management for some patients. Additionally, cortisone injections can weaken nearby tendons, making them more prone to tearing. As a result, physicians typically avoid placing injections directly into or next to a tendon.

While cortisone injections can offer significant relief from knee pain, it's crucial to discuss these potential risks and side effects with your physician. This will enable you to make an informed decision about your treatment options, taking into account both the potential benefits and drawbacks of this approach.

Considerations and Precautions

As with any medical treatment, there are several considerations and precautions to keep in mind when receiving a steroid injection in the knee. Two important factors are the potential impact on blood sugar levels and the potential weakening of tendons.

Blood Sugar Levels

It's crucial to note that cortisone injections may raise blood sugar levels. This particular side effect is especially relevant for diabetic patients. Even though the injection doesn't deliver cortisone directly to the bloodstream, the increase in glucose can impact diabetic patients. Patients with diabetes are advised to monitor their blood sugar levels closely after receiving a cortisone injection [4].

Tendon Weakening

Another important consideration when receiving a steroid injection in the knee is the potential weakening of nearby tendons. Cortisone injections can make tendons more prone to tearing. As a result, physicians typically avoid placing injections directly into or next to a tendon [4].

The weakening of tendons is a significant risk, especially for individuals involved in activities that put a lot of strain on the knees, such as running or jumping. Patients should discuss potential risks with their healthcare provider before deciding to proceed with the injection.

Both the potential rise in blood sugar levels and the risk of tendon weakening underscore the importance of discussing all possible side effects and risks with your healthcare provider before receiving a cortisone injection. It's essential to have a thorough understanding of the potential impacts on your health and to weigh these against the benefits of reduced knee pain and improved mobility.

Efficacy in Knee Osteoarthritis

The use of steroid injections, particularly corticosteroids, in managing knee osteoarthritis has been extensively studied. The effectiveness of these injections can be evaluated in terms of short-term improvement and long-term response.

Short-Term Improvement

Steroid injections in the knee have demonstrated significant short-term improvements in patients with osteoarthritis. According to a PubMed study, the pooled relative risk for improvement up to two weeks after injections was 1.66 (1.37 to 2.0). This indicates a significant reduction in pain and improvement in mobility for patients in the short term.

For every 1.3 to 3.5 patients treated with a steroid injection, one showed improvement, thus reflecting a promising short-term pain relief option for those suffering from knee osteoarthritis.

Improvement	Relative Risk	Patients Treated per Improvement
Up to 2 weeks	1.66 (1.37 to 2.0)	1.3 to 3.5

Long-Term Response

In terms of long-term response, the same PubMed study reports that the pooled relative risk for improvement in symptoms of osteoarthritis of the knee at 16-24 weeks after intra-articular corticosteroid injections was 2.09 (95% confidence interval 1.2 to 3.7).

This suggests that the beneficial effects of the steroid injection in knee can persist for several weeks, providing ongoing relief for patients with knee osteoarthritis. The number needed to treat to achieve one improvement was 4.4.

It's noteworthy that higher doses of cortisone, equivalent to 50 mg prednisone, may be more effective for longer-term response, particularly after 16 or more weeks.

Improvement	Relative Risk	Patients Treated per Improvement
16-24 weeks	2.09 (1.2 to 3.7)	4.4

In conclusion, evidence supports the use of steroid injections for both short-term and long-term improvement in symptoms of knee osteoarthritis. However, the dosage and individual patient characteristics can influence the effectiveness and durability of the treatment. It's always advisable to discuss these factors with a healthcare provider before proceeding with this treatment option.

Administration and Limitations

Understanding the administration process and potential limitations of cortisone shots can help individuals make informed decisions about this treatment option. This section will focus on the common injection sites for cortisone shots and the frequency at which these injections can be safely administered.

Injection Sites

Cortisone shots are a versatile treatment option that can be administered in various joints across the body. The injection contains a corticosteroid medicine for long-term pain relief and a local anesthetic for immediate pain relief. According to the Mayo Clinic, common injection sites include:

Ankle
Elbow
Hip
Knee
Shoulder
Spine
Wrist

In addition to these larger joints, cortisone shots can also benefit the smaller joints in the hands or feet.

These injections are particularly effective in treating inflammatory arthritis like rheumatoid arthritis. They can also be a part of the treatment for other conditions such as osteoarthritis, bursitis, gout, tendonitis, and more.

Frequency of Injections

While cortisone shots can provide significant relief from joint pain, their usage is typically limited due to potential side effects. One of the key concerns is the risk of cartilage damage within the joint. Therefore, the number of cortisone shots that can be administered within a year is limited.

The specific limitation on the frequency of shots depends on various factors, including the joint involved and the individual's diagnosis. The Mayo Clinic suggests that patients discuss these factors with their healthcare provider to determine the appropriate frequency of steroid injection in the knee or other joints.

As with all medical treatments, it's essential for individuals to fully understand the administration process and potential limitations of cortisone shots. By understanding these aspects, patients can make informed decisions about whether this treatment option is right for them.