Articular Capsule of The Knee Joint - Bursae

Bursae

The numerous bursae surrounding the knee joint can be divided into the communicating and the non-cummunicating bursae:

• Communicating bursae:
  • The suprapatellar bursa, the largest bursa, extends the joint space anteriorly and proximally.
  • The subpopliteal recess and semimembranosus bursa are located posteriorly and are much smaller
  • The lateral and medial subtendinous bursae of gastrocnemius are located at the origin of the two heads of the gastrocnemius muscle.
• Non-communicating bursae:
  • The subcutaneous prepatellar bursa is located in front of the patella.
  • The infrapatellar bursa is located under the patella, between the patellar ligament and the fibrous membrane of the joint capsule. It is communicating with the joint space in particular cases.
  • Other less regularly present bursae include the subfascial prepatellar, the subtendinous prepatellar, and the subcutaneous prepatellar bursae.

Adding to the complex structure of the knee space, there are remnants of three embryonic septal divisions of the knee space called synovial plicae:

• The suprapatellar plica dividing the suprapatellar recess
• The infrapatellar plica, in front of the anterior cruciate ligament, reaches from the intercondylar notch to the infrapateller fat pad
• The medial patellar plica, located adjacent to the patella's medial facet, runs vertically along the medial joint capsule