There are many causes of knee pain, many of which can be successfully treated with an injection. Please click on the below links to find out more:
When should a knee injection be considered?
The first and most important factor in deciding whether an injection would be of benefit for you is to get an accurate diagnosis. At Complete out team of highly qualified clinicians combine a physiotherapy assessment with a formal diagnostic ultrasound scan. Once a diagnosis has been reached then an injection can be considered.
The vast majority of people respond very well to a combination of physiotherapy treatment and a progressive rehabilitation program however, if you have been suffering from persistent knee pain which has not responded to conservative treatment options then an injection may be indicated.
Injection therapy can be an effective way to reduce pain, allowing you to undertake a rehabilitation program to address the underlying cause of your symptoms.
Key factors used to assess whether an injection would be of benefit include:
- Considerable pain that has been persistent, or been getting worse, for over 6 weeks.
- Pain that is affecting your ability to sleep at night.
- Pain that is affecting your ability to walk and negotiate stairs and slopes.
- Pain that is affecting your ability to work completely, activities of daily living, or partake in sport and hobbies.
If you feel you relate to one or more of the above factors then an injection may be indicated. If you would like to talk to one of our clinical experts or would like to book an appointment then please contact Complete 020 7482 3875 or email injections@complete-physio.co.uk.
What injection options are there for knee pain?
There are three evidence based injections options available to treat the aforementioned knee conditions. To understand which injection is most appropriate for you depends on your diagnosis and situation. At Complete injections our team of highly experienced physiotherapists will undertake a thorough clinical examination of your knee. This includes an in-depth diagnostic ultrasound scan. Once a formal diagnosis has been made treatment options will be discussed with you prior to the completion of an ultrasound guided injection.
An in-depth description of each injection type can be viewed by clicking on one of the below links.
Steroid injections
Hyaluronic acid injections
Platelet rich plasma injections
What type of knee conditions can be successfully treated with an injection?
Osteoarthritis of the knee
The knee consists of two joints, The tibiofemoral joint (the knee joint proper) and the patellofemoral joint (between the kneecap and the femur). Either joint can be affected by osteoarthritis. Osteoarthritis is a progressive degenerative condition that affects joints, mostly affecting people in their 50s and over. Weight bearing joints are mostly affected with the knee joint being the most commonly affected. Osteoarthritis occurs when a joint is placed under high levels of pressure over a prolonged period of time. The stress associated with this increased joint pressure causes the joint surfaces to rub together causing the cartilage to wear. Over time the bone surfaces underlying the cartilage layer become exposed. This process causes the inner lining of the joint capsule (called the synovial membrane) to become irritated and inflamed When the synovial membrane becomes inflamed (known as synovitis) the knee becomes painful, swollen and stiff. It is this that causes the symptoms associated with osteoarthritis.
General signs and symptoms associated with osteoarthritis of the knee include:
- Pain surrounding the knee joint which can be hard to locate.
- A feeling of knee joint stiffness (especially first thing in the morning).
- Frequent episodes of knee joint swelling (common places for the knee to swell are above the knee cap, on either the inside or outside of the knee and at the back of the knee).
- Limited range of motion. Some people find that the knee can no longer fully straighten or bend.
- Change in shape. An osteoarthritic knee can become larger and thickened as the disease process progresses.
Research supporting injection therapy for osteoarthritis of the knee suggests corticosteroid injections, hyaluronic acid injections and platelet rich plasma injections are all effective methods for relieving pain. Follow the links for more information regarding Knee joint osteoarthritis, Patellofemoral joint osteoarthritis
Meniscal (cartilage) tears
The meniscus (commonly known as cartilage) provides congruency to the knee joint which is inherently irregular in shape; however, its main job role is to create a shock absorbing layer, protecting the knee joint from injury. The meniscus is susceptible to injury and can easily suffer a tear if subjected to either a sudden sharp twist or after repetitive small twists and strains. Meniscal tears are very common and can affect young sports people and older people alike. The meniscus is divided into two. The lateral meniscus (on the outer aspect of the knee joint) and the medial meniscus (On the inner aspect of the knee joint). The medial meniscus bares the largest pressure during weight bearing and twisting and turning motions and is therefore, the most commonly torn.
General signs and symptoms associated with meniscal tear include:
- Immediate, sudden, sharp pain which started after an unexpected twisting or turning motion. This can be during sport or after a more innocuous motion such as turning in the street.
- Pain can be felt more on the inner aspect of the knee in the presence of a medial meniscal tear and more lateral in the presence of a lateral meniscal tear. However, if there is a significant tear or if both medial and lateral menisci are implicated pain can be more widespread.
- A feeling that the knee might collapse under you.
- A locking or in more serious cases locking of the knee joint.
- Localised knee joint swelling
Research supports the use of corticosteroid injections and hyaluronic acid injections for treating the pain associated with meniscal tears. Follow the link for more information regarding Meniscal tears.
Bakers Cyst
A bakers cyst is a swelling located at the back of the knee. It is caused by fluid originating from the knee being pushed out of the joint into a space between two muscles at the back of the leg (the calf and the hamstring). A bakers cyst is not a diagnosis but a sign of other pathology. A bakers cyst is highly suggestive of an injury to the knee joint itself, commonly either a meniscal tear or arthritis (as described above).
General signs and symptoms associated with a bakers cyst follow those of osteoarthritis or meniscal tear (as previously described) however additional symptoms include the following:
- Swelling at the back of the knee joint.
- Pain at the back of the knee.
- Pain or discomfort with bending the knee (such as kneeling or squatting motions).
Treating a bakers cyst using injection therapy often requires the removal of the fluid collection (aspiration) as well as a knee joint injection using corticosteroid or hyaluronic acid. For more information regarding this condition please follow this link Bakers Cyst.
Iliotibial band friction syndrome (ITBFS)
Iliotibial band (ITB) syndrome also known as runners knee is caused when the ITB (a strong band of connective tissue that runs down the outside of the thigh) rubs over the lateral femoral condyle (the outer aspect of the outside of the knee). This rubbing, typically caused by repetitive movements such as running with poor muscle control, causes the ITB to become irritated and inflamed.
General signs and symptoms associated with ITBFS include the following:
- Symptoms typically start gradually without trauma and often soon after starting a sport or increasing your mileage during running.
- A sharp pain located on the outside of the knee.
- Pain that is made worse with walking, stair climbing and sporting activities such as running.
- Tenderness over the outside aspect of the knee.
A guided corticosteroid injection can be used to effectively bathe the ITB, allowing you to rehabilitate the underlying cause of your symptoms. Follow the link for more information regarding Iliotibial band friction syndrome.
Prepatella bursitis
The pre patella bursa is a small fluid filled sack that sits in front of the patella (knee cap). Its job is to provide shock absorption and to reduce friction between the kneecap and the skin. The prepatellar bursa can become irritated and inflamed if subjected to repetitive periods of impact or pressure. People who spend many hours kneeling, such as carpet layers, are susceptible to suffer from prepatellar bursitis.
Furthermore the pre patella bursa is also commonly inflamed due to infection (known as septic bursitis). A septic bursitis will appear red, hot, swollen and will feel very painful. You may also feel systemically unwell. If you feel you may be suffering from a septic prepatellar bursa then Complete injections strongly suggest that you attend your local A&E department as soon as possible.
General signs and symptoms associated with a aseptic prepatellar bursitis include the following:
- Pain over the knee cap.
- Swelling over the knee cap. Swelling can vary in size from small to very large.
- Pain when bending the knee.
- A feeling of tightness over the front of the knee that increases with knee bending tasks.
If you are suffering from septic bursitis then this needs to be treated medically.
If you have an aseptic bursitis then an ultrasound guided aspiration (removal of the fluid) followed by a steroid injection can be used to successfully treat this condition. Follow the link for more information regarding Prepatella bursitis.
Patella tendinopathy
The patella tendon connects the base of the patella (knee cap) to the tibia (shin bone). It is a powerful tendon which anchors the kneecap and the quadricep muscles to the tibia and is responsible for transmitting the high forces, produced by the quadriceps during walking, running and jumping, to the tibia. A patella tendinopathy (also known as jumper’s knee) is caused by repetitively overloading the patella tendon. An irritated tendon can become inflamed (known as tendinitis) if a tendinitis and if not treated effectively and the underlying causes addressed then the healing process may be compromised. A compromised healing process causes the tendon to become thickened and weakened (this is known as a tendinopathy).
General signs and symptoms associated with a patella tendinopathy include the following:
- Pain just below the knee cap.
- Pain made worse as activity levels increase (from walking to running to jumping).
- Pain when standing after prolonged periods of sitting or sleeping.
- Pain with stairs and inclines especially going down.
- A sensation of morning stiffness.
A patella tendinopathy is best treated with physiotherapy, shockwave and a progressive rehabilitation program however in some severe cases an injection may be indicated. Platelet rich plasma injections can be an effective method of treating the underlying tendon pathology. Follow the link for more information regarding Patella tendinopathy.
Fat pad impingement
The fat pad (also known as Hoffer’s fat pad) is a shock absorbent structure that sits behind the patella tendon. It is inherently linked with the inner lining of the joint capsule and the meniscus of the knee. It is highly sensitive and can become symptomatic due to direct impact or secondary to meniscal injury (discussed above). An irritation of Hoffer’s fat pad is known as fat pad impingement.
General signs and symptoms associated with a patella tendinopathy include the following:
- Pain at the front of the knee.
- Swelling around the patella tendon.
- Pain with prolonged periods of sitting or standing.
- Pain with walking and squatting.
- Pain that is made worse with exercising ( running and kicking in particular).
- Pain with wearing high heels.
- Pain with activity after a period of rest.
Treatment for fat pad impingement should be directed at the cause of the symptoms. The vast majority respond very well to physiotherapy rehabilitation however there are some cases that need some extra help. In stubborn cases a guided corticosteroid injection can be used to reduce the pain and inflammation associated with fat pad impingement allowing you to rehabilitate effectively. Follow the link for more information regarding Fat pad impingement.
Pes anserine tendinopathy/bursitis
The pes anserine is the collective name given to three tendons which share a common attachment just below the inner aspect of the knee. The tendons which make up the pes anserine include the semitendinosus, gracilis and sartorius tendons. The pes anserine can become irritated due to a repetitive, inappropriate loading. As previously described a tendon can become inflamed due to repetitive overloading. An irritated tendon is known as tendinitis. If a tendinitis and if not treated effectively and the underlying causes addressed then the healing process may be compromised. A compromised healing process causes the tendon to become thickened and weakened (this is known as a tendinopathy). Furthermore, a pes anserine tendinopathy can lead to the irritation of a small fluid filled sack (known as a bursa). The bursa lays adjacent to the pes anserine and is designed to reduce friction between the tendons and the bone. When bursa is irritated it becomes inflamed. This is known as a bursitis.
General signs and symptoms associated with a pes anserine tendinopathy/bursitis include the following:
- Pain located below the knee over the inner aspect of the upper shin bone which is painful to palpate.
- Pain is made worse with repetitive actions such as running, cycling and squatting.
Many patients suffering from a pes anserine tendinopathy/ bursitis respond positively to physiotherapy, shockwave and rehabilitation exercises. If symptoms do not settle conservatively then a guided injection containing a corticosteroid can be administered to reduce your pain. Follow the link for more information regarding Pes anserine tendinopathy/bursitis.
Commonly asked questions
Why should all injections be carried out under ultrasound guidance?
Ultrasound guidance ensures that the needle is placed smoothly and accurately in the target tissue. Many studies have shown that injections carried out under ultrasound guidance are more accurate and effective, with fewer complications and side effects compared to unguided injections.
The ultrasound scan will identify the most effective and least painful route for the injection, allowing sensitive structures such as nerves, blood vessels, ligaments, bones, and tendons to be identified and avoided.
At Complete all injections are carried out using ultrasound guidance.
For more information, read more.
Are knee injections painful?
Generally speaking, knee injections are very well tolerated with many patients reporting little to no pain at all. Pain thresholds do vary between individuals, so local anaesthetic is used to enhance comfort. Furthermore, ultrasound guidance allows the use of much thinner needles and facilitates a high level of accuracy. This results in less tissue trauma, again making the process more comfortable.
How long does a knee injection last?
Outcomes after a knee injection can vary depending on your condition and its severity. Often the objective is to reduce the pain and provide a window of opportunity to rehabilitate the underlying cause. Physiotherapy would normally begin 1-2 weeks after the injection to maximise its effect. Some patients get long-lasting relief from a steroid injection, and the pain does not return.
For more information, read more.
How many knee injections can I have?
The majority of our patients only require one injection as it provides them with sufficient pain relief to return to their desired activities, be it walking, running, or negotiating stairs without pain.
There are some knee conditions where it is likely that you will require more than one injection, for example:
- if you have a degenerative or an osteoarthritic knee
- if you have more than one condition co-existing, for example a meniscal tear and a fat pad impingement
- if an area is very inflamed or severely damaged and you do not obtain sufficient pain relief from a single injection
The Arthritis Research Council (ARC) suggests no more than three injections in one area over a period of one year.
For more information, read more.
Does a knee injection just ‘numb’ or ‘hide’ the pain?
A steroid injection is an anti-inflammatory drug which reduces inflammation in a region. It does not simply mask the pain. It is designed to control your symptoms, allowing you to address the underlying cause under the guidance of a physiotherapist.
For further information, read more.
How long should I rest after a knee injection?
The amount of time you should rest after an injection depends on your specific situation. It may vary from 3-5 days to several months. It will depend on many factors such as:
- the severity of your injury
- the underlying causes of your pain
- your specific activity goals i.e., to run a marathon or walk up the stairs pain-free
Steroid injections into the knee joint and/or surrounding structures often provide significant pain relief allowing you to move and load your joint or tendon much better than before the injection. It is important that you do not overdo it straight away, for example, by going for your first run in 2 years after only a few days! Your clinician will guide you through what you can and cannot do after the injection to ensure you get the most benefit.
For more information, read more.
What is the cost of a knee injection?
A single ultrasound guided injection costs £250, a single hyaluronic acid injection ranges from £290 to £350, and a single PRP injection costs £450.
For a comprehensive list of prices or for more information read more.
At Complete all our clinicians are highly skilled, knowledgeable, and experienced injection therapists. They carry out hundreds of injections every year and are committed to ensuring our patients have a positive experience.
If you would like to speak to one of our expert clinicians or would like to book an appointment, please either call 020 7482 3875 or email injections@complete-physio.co.uk.