Prepatellar bursitis is also called Prepatellar bursitis or carpenter's knee. A bursa is a fluid-filled sac which ensures there is less friction between body parts. The prepatellar bursa is located superficially between the skin and the patella. The inflammation of a bursa is called bursitis. This inflammation can take form by either an infectious nature (30%) or a non-infectious nature (70%). A direct fall on the patella, an acute trauma, repeated blows or friction on the knee may cause prepatellar bursitis. Other causes include infections or low-grade inflammatory conditions, such as gout, syphilis, tuberculosis or rheumatoid arthritis. Prepatellar bursitis often occurs in specific jobs which involves a position where they work on their knees for a prolonged period of time such as miners, gardeners, carpet layers and mechanics.


The patella is a triangular-shaped bone in front of the knee. It moves up and down in the groove of the femur when you bend and straighten your knee. The patellar tendon is a thick structure that connects the bottom of the patella with the tibia. The upper part of the patella is connected to the quadriceps, which allows the knee extension and moves the patella upwards. Bursae around the knee can be divided into two groups- those around the patella (suprapatellar bursa, the superficial and deep infrapatellar bursae & prepatellar bursa) and those that occur elsewhere (pes anserinus bursa and the iliotibial bursa).


Prepatellar bursitis:- affects men more often than women and it can emerge at all ages. 80% of the people with prepatellar bursitis are men aged between 40 – 60 years. 1/3 of the prepatellar bursitis are septic and 2/3 are non-septic. An infectious prepatellar bursitis emerges more often with children than grown-ups. Prepatellar bursitis occurs often, with at least an annual incidence of 10/100 000. The incidence of prepatellar bursa is probably underestimated because most of the case are non-septic and only patients with the most severe cases of prepatellar bursitis requires admission in the hospital.


Direct trauma/blow to the anterior knee

Frequent falls on the knee

Constant friction between the skin and the patella can be a cause of this condition. By the impact, the damaged blood vessels in the knee result in inflammation and swelling of the bursa. Actually, a bacterial seeding of the bursal sac caused by a hematoma is rare, because of the limited vascular supply of the bursal tissue.

Infection: Typically for a septic prepatellar bursitis is a break in the skin near the bursa, which leads to swelling and pain around this area. This happens when a bacterium (for example S. Aureus, 80% of the cases) have passed across the soft tissues from a break in the skin and begins to multiply within the bursa. When a bursa is infected it can probably cause pain, fever, tenderness and an elevated amount of white blood cells.

Co-existing inflammatory disease- rheumatoid arthritis, gout etc.


  • Pain
  • Swelling
  • Differential warmth around the knee
  • Painful and limited ROM at the knee
  • If bursitis is caused by an infection, pain is associated with fever and chills.


Prepatellar bursitis is often confused with other causes of knee pain including:

  • Medial Collateral Ligament Injury
  • Lateral Collateral Ligament Injury
  • Osteoarthritis
  • Pes Anserinus bursitis
  • Posterior Cruciate Ligament Injury
  • Rheumatoid Arthritis
  • Patellar tendon rupture
  • Chondromalacia patellae
  • Patellofemoral pain.


The medicines that can be thought of use are: -

  • Apis Mel
  • Bryonia
  • Arnica
  • Kali iodatum
  • Ruta graveolens
  • Rhustoxicodendron