Knee Steroid Injections
Ultrasound-Guided Cortisone Injections

A steroid injection in the knee, also called a cortisone injection, delivers a powerful anti-inflammatory medication (a corticosteroid) directly into the knee to reduce inflammation, ease pain and improve movement. It is usually combined with a small amount of local anaesthetic for immediate comfort.

It is one of the most common non-surgical treatments for painful knee conditions, including:

• Knee osteoarthritis: the most frequent reason for a knee cortisone injection.
• Bursitis: inflammation of a fluid-filled sac around the knee.
• Inflammatory arthritis flares affecting the knee joint
• Soft-tissue inflammation, such as patellar tendon or pes anserine problems

The aim is to calm inflammation so that you can move more comfortably and stay active, often helping people delay or avoid more invasive treatment such as knee surgery.

A knee steroid injection is most helpful for people whose knee pain is driven by inflammation and who have not had enough relief from rest, painkillers or physiotherapy. It can ease a wide range of symptoms, including:

• Deep, aching knee pain that worsens with activity or at the end of the day.
• Swelling, warmth or stiffness in the joint.
• Difficulty walking, climbing stairs, kneeling or straightening the knee.
• Disturbed sleep from a painful, inflamed knee.

It is particularly useful for knee osteoarthritis and bursitis, and for settling a painful flare so that you can resume rehabilitation exercises. Your consultant will confirm on ultrasound if inflammation is the main problem, and if a steroid injection is the best course of action.

At the Harley Street Ultrasound Group, your appointment begins with a diagnostic ultrasound assessment, performed by your specialist consultant doctor. Ultrasound shows the joint, the lining, the bursae and the surrounding soft tissues in real time, and is used to confirm where the inflammation is and to rule out other causes of knee pain, such as a meniscal problem, a cyst or significant joint damage, which may need a different approach.

Diagnosing the problem accurately first is what makes the treatment precise. Because the same ultrasound is then used to guide the injection, your consultant can place the needle exactly into the target structure, rather than by external approximations.

If the assessment shows that a different treatment would serve you better, your consultant will tell you on the day. See “What if I don’t need an injection?” below.

A steroid injection in the knee delivers anti-inflammatory cortisone directly into the joint under ultrasound guidance. The corticosteroid calms the inflamed lining of the joint, reducing the swelling and chemical irritation that cause pain, which in turn allows the knee to move more freely.

Because the procedure is performed under real-time ultrasound, your consultant can ensure the injection reaches the exact location and confirm the medication is going precisely to where it is needed.

For many people, a single well-placed cortisone injection is enough to break a painful cycle and allow rehabilitation to progress, offering a route to relief for knee osteoarthritis and inflammation without surgery.

Most patients find the injection far more comfortable than expected. Local anaesthetic is used, so you typically feel a small sting as it goes in, followed by a brief sensation of pressure as the medication is delivered. This is normal and settles quickly.

The appointment usually takes around 20–30 minutes from assessment to completion:

• Your consultant scans the knee to confirm the diagnosis.
• The skin is cleaned and local anaesthetic is applied.
• The injection is delivered under live ultrasound guidance.
• You rest briefly and are given aftercare guidance before you leave.

There is no general anaesthetic and no overnight stay. You can usually drive yourself home, though arranging a lift is sensible if your knee feels sore afterwards.

Your injection is performed by a consultant specialist doctor, not a physiotherapist, nurse or GP. This matters, as the majority of MSK injections in the UK are delivered by non-consultant practitioners, often without ultrasound image guidance.

At the Harley Street Ultrasound Group, you receive both the clinical judgement of a senior specialist and the precision of real-time ultrasound examination in a single appointment. Your consultant assesses the knee, confirms the source of pain, performs the procedure and explains your aftercare personally.

We will never give you an injection you do not need. If, after your ultrasound assessment, your consultant decides an injection is not the right treatment for you, the procedure simply won’t go ahead. You will be charged at our standard diagnostic ultrasound rate, not the full treatment price.

This is a deliberate commitment to clinical integrity. Some providers treat every appointment as a guaranteed procedure; we don’t. You can book knowing that you will receive a genuine specialist assessment first, and that treatment only proceeds when a senior clinician believes it is genuinely warranted.

If an injection isn’t appropriate, your consultant will explain why and set out the alternatives. This may include physiotherapy, a different injection, such as PRP, or onward referral, meaning you still leave with a clear plan.

The local anaesthetic often eases pain almost immediately, though this wears off after a few hours. The steroid itself usually starts to work within a few days, with the fuller anti-inflammatory benefit building over the following one to two weeks.

How long relief lasts varies from person to person and depends on the underlying condition. Many people enjoy several weeks to several months of reduced pain; for some it lasts considerably longer. A cortisone injection treats the inflammation rather than reversing arthritis, so it is best used to control symptoms and create a window to progress with exercise and rehabilitation.

For safety, steroid injections into the same knee are generally limited to a few times a year. Your consultant will advise on sensible frequency and discuss other options if the effect becomes shorter-lived over time.

There is no significant downtime. You can return to everyday activities the same day, though it is sensible to rest the knee and avoid strenuous exercise, heavy lifting or high-impact activity for 24–48 hours to give the medication the best chance to settle.

Some mild soreness or a feeling of fullness in the knee for a day or two is normal, a cold pack and simple painkillers usually help. Keep the area clean and dry for the first day.

Once any initial soreness has settled, gentle movement and a guided exercise or physiotherapy programme help you make the most of the pain relief and protect the knee longer term. You will receive clear written aftercare guidance, and our team remains available if you have any questions as you recover.

A steroid (cortisone) injection is usually the fastest way to calm an inflamed, painful knee, which makes it a strong first choice for a flare of osteoarthritis or for bursitis. Its effect is anti-inflammatory rather than regenerative, and tends to last weeks to months.

Other knee injections work differently:

• PRP (platelet-rich plasma) uses your own concentrated platelets to support tissue healing, often considered where longer-term benefit is the goal.
• Gel / hyaluronic acid (e.g. Ostenil) aims to lubricate and cushion an arthritic knee, and can suit people who prefer to avoid steroids.

There is no single right answer for everyone. The best option depends on your diagnosis, your goals and close examination of your knee under ultrasound. Your consultant will talk you through the choices, and you can read more on our dedicated PRP knee injection and Ostenil knee injection pages.

An ultrasound-guided steroid (cortisone) injection in the knee at the Harley Street Ultrasound Group is £525, all fees inclusive. There are no extra charges for the consultant assessment, the diagnostic ultrasound, the procedure itself, or your written report.

What’s included in the price:

• Consultant specialist assessment and diagnostic ultrasound
• Ultrasound-guided steroid (cortisone) injection
• Local anaesthetic and all consumables
• Written report and tailored aftercare guidance
• No referral required and no waiting list

Importantly, if your consultant assesses you and decides an injection is not clinically appropriate, you are charged only at our standard diagnostic ultrasound rate, not the procedure price. We accept self-pay and most major UK private health insurers; please confirm cover with your insurer before booking.

Coming to us privately does not affect your NHS care. Our goal is to get you answers and treatment quickly, without the long waits often involved in accessing injection therapy on the NHS.

You are seen by a consultant specialist who can assess, diagnose and, where appropriate, treat your knee in a single visit. Your report and images can be shared securely with your NHS GP or any specialist, and if your situation needs onward NHS care your consultant will write to your GP accordingly.

We don’t want you waiting months in pain when effective treatment is available now.