Assistant
Definition
By Gregory R. Waryasz, MD
The knee joint capsule of the musculoskeletal system is characterized by covering the knee joint.
It is part of the knee joint. It consists of a fibrous layer with an internal synovial membrane.
Its unique structural feature is that it encloses the knee joint incompletely. It has some thickened parts but overall it is a thin structure. It attaches to the femur proximal to the articular portions of the condyles. On the posterior knee, the capsule covers the condyles and the intercondylar fossa. There is an opening in the capsule to allow for passage of the popliteal tendon. The inferior part of the capsule attaches to the tibial plateau except where the popliteus courses along the bone. The quadriceps tendon and patellar ligament are continuous with the capsule.
The knee joint capsule as well as all other bones, muscles, and ligaments of the body are derived of mesodermal origin in the embryo.
The function of the knee joint capsule is to help with maintaining structure of the knee joint.
Common diseases include fracture and dislocation which can tear the capsule.
Commonly used diagnostic procedures include clinical history, physical exam, and MRI.
It is usually treated with physical therapy and NSAIDs. Surgery can be performed either with a large open incision or performed with arthroscopy.
References
Elstrom J, Virkus W, Pankovich (eds), Handbook of Fractures (3rd edition), McGraw Hill, New York, NY, 2006.
Koval K, Zuckerman J (eds), Handbook of Fractures (3rd edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.
Lieberman J (ed), AAOS Comprehensive Orthopaedic Review, American Academy of Orthopaedic Surgeons, 2008.
Moore K, Dalley A (eds), Clinically Oriented Anatomy (5th edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.