How Long Does a Cortisone Injection Last? A Comprehensive Guide to Joint and Tendon Relief
Medically Reviewed By: Dr Mehrdad Bordbar BMBS MMedSc MRCGP AFMCP Clinic: Olivine Clinic, 5 Hamslade Green, Poundbury, Dorchester, DT1 3DP
If you are struggling with persistent joint pain, tendonitis, or severe inflammation, you have likely been offered or considered a cortisone injection. Whether it is a stiff shoulder that keeps you awake at night or an arthritic knee that limits your daily walks around West Dorset, these injections are a cornerstone of modern musculoskeletal medicine.
But the most pressing question patients ask when they visit our private GP practice is: "How long does a cortisone injection last?"
The Short Answer: On average, the pain-relieving effects of a cortisone injection last for about three months. However, this duration varies significantly from patient to patient. Some individuals may experience relief for only a few weeks, whilst others may enjoy improved function and reduced pain for up to six months or longer. Cortisone injections are not a permanent cure; rather, they provide a crucial "window of opportunity" to engage in physiotherapy or allow you to attend important life events pain-free.
In this comprehensive guide, we will explore exactly what a steroid injection is, how it works in the body, the specific conditions it treats, and its potential side effects. We will also discuss longer-lasting alternatives, such as hyaluronic acid injections, offered by Dr Mehrdad Bordbar at the Olivine Clinic in Dorchester.
1. What is a Cortisone (Steroid) Injection?
When medical professionals refer to a "cortisone injection" or "steroid injection," they are talking about corticosteroids. It is vital to distinguish these from anabolic steroids, which are sometimes misused in bodybuilding. Corticosteroids are synthetic versions of cortisol, a naturally occurring hormone produced by your adrenal glands.
The Mechanism of Action
How exactly does a cortisone injection work? When you sustain an injury or develop a condition like osteoarthritis, your body’s immune system triggers an inflammatory response. This involves a rush of white blood cells and inflammatory chemicals (such as prostaglandins and cytokines) to the affected area. While inflammation is a natural healing process, chronic inflammation leads to swelling, heat, redness, and persistent pain.
Corticosteroids are powerful anti-inflammatory medications. When injected directly into a joint space (intra-articular) or around a tendon (peri-articular), the steroid acts at a cellular level. It enters the cells and alters the expression of genes, effectively switching off the production of inflammatory proteins.
Pain Reduction and Improved Function
Because the injection is delivered directly to the site of the pathology, it provides a highly concentrated dose exactly where it is needed, minimising systemic (whole-body) exposure. By suppressing the local inflammation, the injection rapidly reduces swelling and nerve irritation.
The primary goal of a steroid injection is twofold:
Reduce Pain: By calming the inflammatory cascade.
Improve Function: By reducing pain and swelling, the joint or tendon regains its mobility, allowing you to move more freely.
2. What Conditions Require a Cortisone Injection?
Cortisone injections are incredibly versatile and are utilised across a wide spectrum of orthopaedic and rheumatological conditions. According to the National Institute for Health and Care Excellence (NICE) guidelines, corticosteroid injections are a recognised adjunct therapy for moderate to severe joint pain when standard oral analgesics have failed.
Here are the primary conditions we treat at the Olivine Clinic:
Arthritis in the Joints
Osteoarthritis is the "wear and tear" arthritis that degrades the smooth cartilage capping the ends of our bones. When this cartilage thins, the joint becomes inflamed and painful.
The Knees: Weight-bearing joints are highly susceptible to osteoarthritis. An injection can rapidly decrease the swelling (effusion) that makes the knee feel tight and painful to bend.
The Shoulder: Conditions such as glenohumeral osteoarthritis or acromioclavicular (AC) joint arthritis respond well to localised cortisone.
The Ankle: Often affected by post-traumatic arthritis (following an old fracture or severe sprain), cortisone can help restore walking tolerance.
Small Digits (Thumb and Wrists): Base of thumb arthritis (carpometacarpal joint osteoarthritis) is notoriously debilitating for simple tasks like opening jars or turning keys. An ultrasound-guided injection into these tiny joints can restore profound hand function.
Tendinosis and Tendonitis
While the terms are often used interchangeably, tendonitis refers to acute inflammation of a tendon, whereas tendinosis refers to chronic degeneration of the tendon fibres. Steroids are primarily used to calm the inflammatory component surrounding the tendon (the paratenon or bursa).
Shoulder Tendinosis/Tendonitis: Rotator cuff tendinopathy is a leading cause of shoulder pain. An injection into the subacromial space can alleviate the severe catching pain associated with overhead movements.
Hip Tendinosis: Also known as greater trochanteric pain syndrome or gluteal tendinopathy, this causes severe pain on the outside of the hip, making it impossible for patients to sleep on their side.
Bursitis
A bursa is a small, fluid-filled sac that acts as a cushion between bones and overlying soft tissues. When these become inflamed, it is called bursitis.
Triceps Brachii Bursitis: Located at the back of the elbow (often associated with the olecranon bursa), inflammation here can cause a painful, golf-ball-sized swelling. Cortisone can rapidly shrink the inflamed bursa and relieve the tension.
3. How Long Do the Effects Actually Last?
As noted in our introduction, the clinical effects of a cortisone injection generally last for about three months. However, this is a statistical average, and real-world outcomes operate on a bell curve.
The Variability of Duration
Short Responders: Some patients may only experience 3 to 4 weeks of relief. This can happen if the underlying structural damage (such as bone-on-bone arthritis) is extremely severe, meaning the mechanical friction quickly triggers new inflammation.
Long Responders: Conversely, for relatively minor inflammatory flare-ups, a single injection might provide 6 to 12 months of relief, or even resolve an acute problem entirely.
The "Window of Opportunity" Strategy
It is crucial to understand that cortisone is an anti-inflammatory, not a regenerative medicine. It does not rebuild torn tendons or regrow worn cartilage. Therefore, we use cortisone injections strategically to "buy time."
Engaging in Rehabilitation and Physiotherapy: When you are in severe pain, undertaking a physiotherapy programme is nearly impossible. Attempting strengthening exercises when a joint is acutely inflamed often makes the pain worse. A cortisone injection breaks the pain cycle. The 3-month pain-free window allows you to engage fully with a physiotherapist to strengthen the surrounding muscles, improve joint mechanics, and address the root cause of the problem.
Attending Important Functions: Sometimes, timing is everything. If you have a severe osteoarthritis flare-up but are due to walk down the aisle at a family wedding, attend a university graduation, or embark on an important family holiday, an injection can provide the rapid, reliable relief needed to enjoy these life milestones without the burden of severe pain.
4. The Longer-Lasting Alternative: Hyaluronic Acid Injections
While cortisone is excellent for rapid anti-inflammatory relief, it is not the only injectable option. For patients suffering from osteoarthritis of the knee who want a longer-lasting, non-steroidal solution, Dr Mehrdad Bordbar offers Hyaluronic Acid (HA) injections at the Olivine Clinic.
What is Hyaluronic Acid?
Hyaluronic acid is a naturally occurring substance found in the synovial fluid of healthy joints. It acts as a thick, viscous lubricant and shock absorber, allowing the bones to glide smoothly over one another. In an arthritic knee, the natural hyaluronic acid breaks down, becoming thin and watery, which increases friction and pain.
How Does it Differ from Cortisone?
Mechanism: Rather than acting purely as a chemical anti-inflammatory, HA acts mechanically. This process, known as viscosupplementation, restores the lubricating properties of the joint fluid.
Duration: While cortisone acts quickly but fades in a few months, hyaluronic acid takes a few weeks to reach its full effect but can last significantly longer—often providing relief for 6 to 12 months.
Safety Profile: Because HA is a natural substance, it does not carry the same risks of tissue thinning or blood sugar spikes associated with steroids, making it an excellent option for repeated use or for diabetic patients.
5. The Cons and Side Effects of Cortisone Injections
Patient safety is our primary concern at the Olivine Clinic. While cortisone injections are generally safe when administered by a trained medical professional like a Private GP, they are not without potential side effects and drawbacks. According to NHS guidelines on corticosteroid injections, patients must be fully informed of the following risks:
Short-Term Side Effects
The "Steroid Flare": In about 5% to 10% of cases, the injected corticosteroid crystals can cause a temporary irritation in the joint. This can lead to increased pain and stiffness for the first 24 to 48 hours before the therapeutic effects begin.
Facial Flushing: Some patients experience a temporary red, warm flush in their face and chest for a day or two post-injection.
Blood Sugar Spikes: If you have diabetes, the systemic absorption of the steroid (even in small amounts) can cause your blood glucose levels to spike for up to a week. Careful monitoring is required.
Localised Tissue Effects
Skin Depigmentation: The skin around the injection site (particularly for superficial injections like the wrist or elbow) may lose its pigment and become pale.
Fat Atrophy (Lipoatrophy): The subcutaneous fat at the injection site may thin out, leaving a small dimple in the skin.
The Risks of Repeated Injections
This is arguably the most significant "con" of cortisone therapy. Repeated steroid injections into the same joint or tendon can have detrimental long-term effects.
Cartilage Degeneration: Frequent intra-articular steroid injections (e.g., more than three times a year) can accelerate the breakdown of articular cartilage, potentially worsening osteoarthritis in the long run.
Tendon Weakening and Rupture: Corticosteroids inhibit collagen synthesis. Injecting directly into a tendon, or repeatedly injecting around it, can weaken the tendon structure, making it highly susceptible to spontaneous rupture (a particular risk in the Achilles and patellar tendons).
Because of these risks, medical best practice dictates spacing injections at least 3 to 4 months apart, and limiting the total number of injections into a single anatomical site.
6. Contraindications: Who Should NOT Have a Steroid Injection?
While cortisone is a valuable tool, there are specific circumstances where it is medically contraindicated. Dr Bordbar will conduct a thorough medical history before proceeding with any treatment, ensuring you do not fall into the following categories:
Impending Live Vaccines: Corticosteroids suppress the immune system. If you are due to have a live vaccine (such as Yellow Fever for travel, or certain Shingles/MMR vaccines), you must wait. Standard guidelines suggest avoiding steroid injections for at least a few weeks before and after receiving a live vaccine to ensure your body mounts a proper immune response.
Upcoming Joint Surgery: If you are scheduled to have a joint replacement (e.g., a total knee or hip replacement) within the next 3 to 6 months, an injection is generally contraindicated. Steroids can suppress local immune function and significantly increase the risk of a post-operative joint infection.
Active Infections: If you have an active systemic infection, or a local infection (cellulitis) overlying the joint, injecting a steroid can cause the infection to spread rapidly.
Known Allergies: If you have a documented allergy to the specific corticosteroid medication (e.g., Depo-Medrone, Kenalog) or the local anaesthetic mixed with it (e.g., Lidocaine, Bupivacaine), the procedure cannot be performed.
Bleeding Disorders: Patients on strong blood thinners (anticoagulants like Warfarin or Apixaban) or those with bleeding disorders (haemophilia) require careful risk assessment, as the injection needle can cause internal bleeding into the joint (haemarthrosis).
7. Frequently Asked Questions (FAQs)
To help our Dorchester and West Dorset patients make an informed decision, we have compiled the most common questions we receive in the clinic.
Does a cortisone injection hurt?
The injection is usually well-tolerated. We often mix the corticosteroid with a local anaesthetic (such as lidocaine). You will feel a sharp scratch from the needle and a brief sensation of pressure or stinging as the fluid is injected, but the local anaesthetic quickly numbs the area.
How long does it take for a cortisone injection to work?
While the local anaesthetic provides immediate relief for a few hours, the actual steroid takes time to alter the inflammatory cascade. Most patients notice an improvement within 3 to 7 days, though it can take up to two weeks to see the maximum benefit.
Can I drive home after a steroid injection?
Generally, yes, but it depends on the injection site. If you have an injection in your right knee or ankle, the local anaesthetic might temporarily affect your pedal control or make the limb feel heavy. In such cases, it is safer to bring a driver or take a taxi home from our Poundbury clinic.
What should I do for the first 24 hours after the injection?
Rest the joint. We strongly advise relative rest for the first 48 hours to prevent the injected fluid from being pumped out of the joint space and into the systemic circulation. Avoid heavy lifting, long walks, or repetitive movements. You can apply an ice pack (wrapped in a cloth) if you experience a steroid flare.
How many cortisone injections can I have in a lifetime?
There is no strict lifetime limit, but guidelines recommend limiting injections into a single weight-bearing joint to a maximum of three to four times per year. For tendons, the limit is often even stricter to avoid the risk of tendon rupture. Your Private GP will formulate a long-term plan that doesn't rely solely on repeated steroids.
8. Next Steps: Reclaim Your Mobility in Dorchester
Living with chronic joint or tendon pain can severely impact your quality of life, making everything from a round of golf to a simple trip to the shops feel like a monumental task. You do not have to wait months in pain for a solution.
At the Olivine Clinic in Dorchester, Dr Mehrdad Bordbar provides rapid-access, comprehensive musculoskeletal assessments. Whether you require a fast-acting cortisone injection to break the pain cycle and engage in physiotherapy, or a longer-lasting hyaluronic acid injection to manage knee osteoarthritis, we offer bespoke, evidence-based treatment plans.
Ready to live pain-free? Take the first step towards recovery.
Location: Olivine Clinic, 5 Hamslade Green, Poundbury, Dorchester, DT1 3DP.
Action: Read our service page on Ultrasound-Guided Joint injections to book your appointment.
Medical Disclaimer
The information provided in this article is for educational and informational purposes only and does not constitute formal medical advice. Every patient's medical history is unique. Always consult with a qualified healthcare professional or Private GP before undergoing any medical procedures or injections. This content has been formatted in alignment with current (2026) medical consensus and guidelines.
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