Knee bursitis is the inflammation of a bursa on the knee. It’s common in jobs where you have to kneel a lot. But, how do you know if you have bursitis? How many knee bursitis types are there?
The short answer is that we classify bursitis according to:
- The location of the bursa. Prepatellar bursitis is the inflammation of the prepatellar bursa.
- The cause of inflammation. Septic bursitis is the only type of bursitis that requires antibiotics.
- The most common occupation affected by bursitis. “Housemaid’s knee” is another name for the inflammation of the prepatellar bursa.
That said, let’s take a closer look at the most common types of knee bursitis and how to treat them. To top it off, I’ll even show you a few other conditions with similar symptoms
7 common types of knee bursitis
First of all, a bursa is a type of soft tissue that looks like a fluid-filled sac. You can find these bursae between skin, tendons, ligaments, and bone.
They produce a fluid that lubricates and helps reduce friction between these tissues.
That said, bursitis happens when these bursae become inflamed or irritated.
We have +150 bursae, distributed in different parts of our bodies. (1, 2)
Our knees, in particular, have 14. And, since there are so many of them, they’re named after their locations or their causes. Each type of knee bursitis somewhat feels and looks different, too.
Let’s take a look at the most common types of bursitis of the knee:
1) Septic bursitis
Septic bursitis happens when an infection is what’s causing the bursa irritation.
It’s common in people with occupations with constant kneeling. Like plumbers, carpet layers, or the clergy. (2)
Athletes and males between 40-60 years of age are also prone to septic bursitis. (1, 2)
It has symptoms similar to those of non-infected bursitis, including (1):
- Pain and swelling on the affected area.
- Decreased range of motion on the knee joint.
- Redness of the skin, usually warm to the touch.
But, in septic bursitis, you may also have a wound on the area. Some people may have a fever as well.
How does it happen?
Septic bursitis can happen after: (2)
- An injury punctures the bursa.
- An injection to relieve the symptoms of non-septic bursitis.
- A previous infection spreads from the blood to the bursa.
Your doctor may also ask for blood tests or fluid analysis to make sure that you have an infected bursa. The tests also let them know what bacteria has invaded the sacs so they can give you the proper antibiotics. (2)
How is it treated?
The treatment for an infected bursa always includes antibiotics. They’re usually taken orally unless your doctor thinks you need intravenous medication.
The treatment usually lasts at least 10 days in mild cases, or until the fluid is clear of infection. (2)
Severe or recurrent cases may need surgery to drain the infection. Another option is removing the infected bursa altogether.
This can help: 5 treatments for knee bursitis.
2) Prepatellar bursitis
This happens when there’s an inflammation of the bursa on top of the kneecap (i.e. prepatellar bursa).
Its location makes it prone to inflammation after frequent kneeling. Hence, why prepatellar bursitis is also called:
- Carpenter’s knee.
- Kneecap bursitis.
- Housemaid’s knee.
The prepatellar bursa is also the most commonly affected bursae of the knee. It’s also the second most affected overall. with bursa of the elbow coming in first. (3)
Prepatellar bursitis symptoms include:
- Knee pain.
- Mild to severe swelling on top of the knee.
- Movement limitation in the knee joint.
How does it happen?
The inflammation of a bursa often happens after repetitive kneeling. This is usually due to your occupation or hobbies.
Also, people with these conditions are prone to develop prepatellar bursitis:
- Diabetics.
- Chronic steroid users.
- People with rheumatoid arthritis or gout.
How is it treated?
After your doctor rules out infection, the treatment for prepatellar bursitis includes (3):
- Physical therapy to restore your strength, flexibility, and range of motion.
- Anti-inflammatory medication to reduce swelling and pain.
- Fluid aspiration if necessary.
Going to physical therapy is the quickest way to manage non-infected knee bursitis.
Also, if your occupation requires you to kneel most of the time, a PT can help you prevent another episode.
Attention! Here at Knee Force, we can help connect you with a qualified physical therapist in your area. Let us help you manage that bursitis!
3) Pes anserine bursitis
The “pes anserine” area is on the inside of the knee. It’s the insertion point of three muscles:
- The semitendinosus – one of the hamstring muscles.
- The gracilis.
- The sartorius.
The pes anserine bursa is between the bone and the insertion point of the tendons When it becomes inflamed, it can cause pain on the inner side of the knee joint while doing these movements (4):
- Rising from a seated position.
- Sitting with your legs crossed.
- Crossing one leg over the other.
How does it happen?
This type of injury is usually caused by a direct hit in the area. It can also happen due to overuse of the muscles. (4)
Certain health issues can make you prone to develop this type of tendon bursitis as well (4):
- Obesity.
- Diabetes.
- Knee arthritis.
- History of a tear on the medial meniscus or the medial collateral ligament.
How is it treated?
The treatment is similar to other non-infected bursitis of the knee (4):
- Rest.
- Physical therapy.
- Anti-inflammatory drugs.
If you’re an athlete, you may also need to work on your hamstring muscles. There could be some kind of movement imbalance that’s overworking your hammies. Fixing the imbalance should help prevent future episodes.
If you’re obese, it’s important to get down to your normal BMI. Again, this helps prevent future episodes of this type of knee bursitis. (4)
If you have arthritis, your treatment also has to include ways to manage this issue. (4)
4) Infrapatellar bursitis
There are two infrapatellar bursae:
- The superficial. It’s between the bony prominence at the top of the shinbone and the overlying skin.
- The deep infrapatellar bursa is between the patellar tendon and the shinbone.
How does it happen?
This type of knee bursitis can happen after prolonged kneeling. So, it’s similar to prepatellar bursitis but it’s not as common.
The main difference is that superficial infrapatellar bursitis can be painless. The prepatellar tends to be painful. (5)
The bursa can become inflamed and painful due to an infection or an inflammatory disease.
Some health problems can make you prone to develop this type of knee bursitis:
How is it treated?
As usual, treatment includes rest, rehabilitation, and medication. But, this type of bursitis may also need its fluids aspirated in severe cases.
That said, you might not even need any treatment at all if you don’t have symptoms. Or, if they’re mild enough not to disturb your daily activities. (5)
5) Suprapatellar bursitis
The suprapatellar bursa is between the tendon of the quadriceps and the thigh bone.
It reduces friction on the tendon which, in turn, smoothens out knee joint movements. (6)
It’s treated like other cases of non-infected bursitis.
6) Medial collateral ligament bursitis
The medial collateral ligament (MCL) is a band of soft tissue located on the inner side of the knee. It helps keep the joint stable.
When the MCL bursa becomes inflamed, it can mimic the symptoms of a meniscus tear or an MCL tear.
Your doctor will likely ask for an MRI to see which structure is causing the pain and swelling. (6, 7)
Related: The best knee braces for MCL sprains (with reviews)
7) Iliotibial bursitis
The iliotibial band is a thick band of soft tissue. It goes from the outer side of your hip down to the outer side of your knee. It has a bursa under it, right before it attaches to the knee.
The friction between the band and the bursa can irritate it and cause bursitis. This is also why this type of tendon bursitis is common in runners. (6)
What can be mistaken for bursitis?
Several health issues can share the symptoms of bursitis.
Of course, they’re treated differently. So, it’s important to make sure it’s bursitis and not something else.
Here are a few examples:
Here are common issues that can be mistaken for knee bursitis:
Rheumatoid arthritis
Rheumatoid arthritis (RA) is an autoimmune and inflammatory disease. Among other things, it causes painful swelling on the joints.
It usually affects the hands and knees. It’s mostly treated with medication and lifestyle changes.
People with this condition have more risk to develop bursitis. Although, not every person with RA will have bursitis. (8)
Gout
This condition also affects the joints, mostly the big toe. It’s caused by the build-up of uric acid crystals in the joints. As with RA, the treatment for gout includes medication and lifestyle changes.
It looks and feels like bursitis, especially at the elbow, prepatellar, and infrapatellar bursa. (8)
These patients are also prone to develop a bursitis infection. (8)
Knee osteoarthritis
This is the wear and tear of the knee cartilage. Severe cases feel constant knee pain and have some swelling around the knee.
It’s treated with exercise and medication if needed. People with advanced osteoarthritis may need total knee replacement.
Learn more: Knee osteoarthritis – causes, symptoms, treatments, and more!
Baker’s cyst
This is a fluid-filled cyst behind the knee. Severe cysts look like a big lump on the back of the knee. People with osteoarthritis can be prone to develop a baker’s cyst.
The cyst itself may or may not be painful. Most are asymptomatic.
Other common sites of bursitis in the body
Research suggests that bursitis accounts for 0.4% of all visits to primary care clinics. The most common locations of bursitis are (1):
Hip bursitis
It’s also known as “trochanteric bursitis.”
The pain from hip bursitis tends to be on the side of the hip. Females and obese people are prone to have it. (8)
The main cause is a direct impact on the side of the hip, like a fall.
Elbow bursitis
Also called “student’s elbow,” this affects the bursa of the olecranon – on the tip of your elbow. It has a high risk of infection. (1)
The main cause is prolonged or repetitive pressure on the elbow. People prone to develop it include (1):
- Students – hence the name.
- People who perform manual labor for a living – plumbers, gardeners, mechanics, construction workers…
Shoulder bursitis
This one usually affects the bursa under the supraspinatus tendon, near the tip of your shoulder.
This bursa can become irritated with repetitive movements with an elevated shoulder. Like pitching in baseball or lifting luggage overhead. (1)
If untreated, people may develop further shoulder complications. For example, frozen shoulder or muscle atrophy. (8)
Ischial bursitis
This type of bursitis affects the bursa near your sit bones. That’s why it’s also known as “weaver’s bottom.” Its main cause is prolonged sitting on a hard surface. (1)
The pain is worse while sitting and can radiate down the back of the leg. It can be easily confused with sciatica pain.
FAQs:
Is walking good for knee bursitis?
If your knee doesn’t hurt when you walk, then, it’s okay.
If walking worsens your pain, it’s best to avoid walking for a few days unless you have to. This will let your body heal the bursitis.
What causes bursitis?
A bursa can become inflamed because of:
– Prolonged pressure on the bursa.
– Repetitive movements – the friction can irritate the bursa as well.
– A direct impact on the bursa.
– A previous inflammatory condition, like arthritis or gout.
What are the symptoms of bursitis?
The symptoms of any bursitis can include:
– Pain and swelling on the affected area.
– Movement limitation of the related joints.
– Skin redness and fever if it’s infected.
Conclusion: 7 types of bursitis on the knee
Bursitis is inflammation of the bursa. A bursa is a fluid-filled sac that eases the movement between tissues.
Bursae get irritated, usually after a direct impact or repetitive movements. In the knee, the most common cause is prolonged kneeling.
Prepatellar bursitis is the most common type of bursitis on the knee. It’s also called “housemaid’s knee,” or “carpenter’s knee.”
If it’s infected, you’ll need to take some antibiotics. If it’s not, it will probably get better with some rest and rehabilitation.
Some conditions can be mistaken for bursitis or make you prone to it – like arthritis or gout. If you have any inflammatory disease, check with your doctor to see whether you have bursitis or not.
Resources
- Lohr, Kristine. “Bursitis: Practice essentials.” [Updated 2020 Dec 11]. Medscape. Available from: https://emedicine.medscape.com/article/2145588-overview
- Truong J, et al. “Septic Bursitis.” [Updated 2021 Jan 22]. StatPearls. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470331/
- Rishor-Olney CR, Pozun A. “Prepatellar Bursitis.” [Updated 2021 Feb 22]. StatPearls. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557508/
- Mohseni M, Graham C. “Pes Anserine Bursitis.” [Updated 2020 Nov 26]. StatPearls. Available from: https://www.ncbi.nlm.nih.gov/books/NBK532941/
- Jain, Mantu et al. “Infrapatellar bursitis presenting as a lump.” BMJ case reports vol. 14,5 e243581. 25 May. 2021, doi:10.1136/bcr-2021-243581
- Chatra, Priyank S. “Bursae around the knee joints.” The Indian journal of radiology & imaging vol. 22,1 (2012): 27-30. doi:10.4103/0971-3026.95400
- Schein, Aaron et al. “Structure and function, injury, pathology, and treatment of the medial collateral ligament of the knee.” Emergency radiology vol. 19,6 (2012): 489-98. doi:10.1007/s10140-012-1062-z
- Williams CH, Jamal Z, Sternard BT. “Bursitis.” [Updated 2021 Jan 17]. StatPearls. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513340/