The popliteal fossa (also referred to as hough, /sup> or kneepit in analogy to the cubital fossa) is a shallow depression located at the back of the

knee In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the ...

joint A joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw- ...

. The bones of the popliteal fossa are the

femur The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates ...

and the

tibia The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it conn ...

. Like other flexion surfaces of large joints (

groin In human anatomy, the groin (the adjective is ''inguinal'', as in inguinal canal) is the junctional area (also known as the inguinal region) between the abdomen and the thigh on either side of the pubic bone. This is also known as the medial comp ...

armpit The axilla (also, armpit, underarm or oxter) is the area on the human body directly under the shoulder joint. It includes the axillary space, an anatomical space within the shoulder girdle between the arm and the thoracic cage, bounded superior ...

cubital fossa The cubital fossa, chelidon, or elbow pit, is the triangular area on the anterior side of the upper limb between the arm and forearm of a human or other hominid animals. It lies anteriorly to the elbow (Latin ) when in standard anatomical position ...

and essentially the anterior part of the

neck The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In ...

), it is an area where blood vessels and nerves pass relatively superficially, and with an increased number of

lymph node A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that includ ...

Structure

Boundaries

The boundaries of the fossa are:

Roof

Moving from superficial to deep structures, the roof is formed by: # the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different ...

. # the

superficial fascia A fascia (; plural fasciae or fascias; adjective fascial; from Latin: "band") is a band or sheet of connective tissue, primarily collagen, beneath the skin that attaches to, stabilizes, encloses, and separates muscles and other internal organ ...

. This contains the small saphenous vein, the terminal branch of the posterior cutaneous nerve of the thigh, posterior division of the

medial cutaneous nerve The anterior cutaneous branches of the femoral nerve consist of the following nerves: ''intermediate cutaneous nerve'' and ''medial cutaneous nerve''. Intermediate cutaneous nerve of thigh The intermediate cutaneous nerve (middle cutaneous nerve) ...

lateral sural cutaneous nerve The lateral sural cutaneous nerve of the lumbosacral plexus supplies the skin on the posterior and lateral surfaces of the leg. The lateral sural cutaneous nerve originates from the common fibular nerve''(L4-S2)'' and is the terminal branch o ...

, and

medial sural cutaneous nerve The medial sural cutaneous nerve ''(L4-S3)'' is a sensory nerve of the leg. It supplies cutaneous innervation the posteromedial leg. Structure The medial sural cutaneous nerve originates from the posterior aspect of the tibial nerve of the ...

. # the popliteal fascia.

Floor

The floor is formed by: # the popliteal surface of the femur. # the capsule of the knee joint and the

oblique popliteal ligament The oblique popliteal ligament (posterior ligament) is a broad, flat, fibrous band on the posterior knee representing an expansion of the tendon of the semimembranosus muscle. It attaches onto the intercondylar fossa and lateral condyle of the fe ...

. # strong fascia covering the

popliteus muscle The popliteus muscle in the leg is used for unlocking the knees when walking, by laterally rotating the femur on the tibia during the closed chain portion of the gait cycle (one with the foot in contact with the ground). In open chain movements ...

Structures within the popliteal fossa include, (from superficial to deep): *

tibial nerve The tibial nerve is a branch of the sciatic nerve. The tibial nerve passes through the popliteal fossa to pass below the arch of soleus. Structure Popliteal fossa The tibial nerve is the larger terminal branch of the sciatic nerve with root val ...

* common fibular nerve (also known as the common peroneal nerve) *

popliteal vein The popliteal vein is a vein of the lower limb. It is formed from the anterior tibial vein and the posterior tibial vein. It travels medial to the popliteal artery, and becomes the femoral vein. It drains blood from the leg. It can be assessed ...

popliteal artery The popliteal artery is a deeply placed continuation of the femoral artery opening in the distal portion of the adductor magnus muscle. It courses through the popliteal fossa and ends at the lower border of the popliteus muscle, where it branche ...

, a continuation of the

femoral artery The femoral artery is a large artery in the thigh and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery or profunda femoris artery and descends along the anteromedial part of the thigh in the f ...

* small saphenous vein (termination)Clinically Oriented Anatomy by Moore, 6th edition * Popliteal lymph nodes and vessels It is of note that the common fibular nerve also begins at the superior angle of the popliteal fossa.

Additional images

File:Gray434.png, Muscles of the gluteal and posterior femoral regions. File:Gray582.png, Small saphenous vein and its tributaries. File:Gray551.png, The popliteal, posterior tibial, and peroneal arteries. File:Gray832.png, Nerves of the right lower extremity Posterior view. File:Slide2DADE.JPG, Muscles of thigh. Lateral view.

References

External links

* (, , ) * {{Authority control Lower limb anatomy Knee