Anterior Compartment of the Thigh

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Anterior Compartment of the Thigh

After removing the skin from the anterior thigh, you can identify the cutaneous nerves and veins of the thigh and the fascia lata. The fascia lata is a dense layer of deep fascia surrounding the large muscles of the thigh. The great saphenous vein reaches the femoral vein by passing through a weakened part of this fascia called the fossa ovalis which has a sharp margin called the falciform margin. Located high in the thigh, just below the inguinal ligament, are the superficial inguinal lymph nodes, usually arranged in a T-shape. These nodes receive lymph drainage from the entire lower limb and the superficial structures of the perineum. The cutaneous nerves found piercing the deep fascia are the: lateral femoral cutaneous intermediate cutaneous, branches of the femoral nerve medial cutaneous, branches of the femoral nerve

The anterior compartment of the thigh contains a large muscle, consisting of four heads, the quadriceps femoris muscle. This is a strong extensor of the knee. The four heads of the quadriceps femoris muscle are the: rectus femoris vastus lateralis vastus medialis vastus intermedius One other muscle of the anterior compartment is the sartorius. The thigh is completely surrounded by a dense layer of deep fascia called the fascia lata. This fascia is particularly thickened on the lateral aspect of the thigh and is named the iliotibial tract. This tract extends from the iliac crest to the lateral condyle of the tibia.

Femoral Triangle

The femoral triangle is an anatomical region of the upper thigh that has the following boundaries: inguinal ligament sartorius adductor longus The floor of the triangle is made up of the: iliopsoas muscle pectineus muscle The contents of the femoral triangle from lateral to medial are: femoral nerve femoral artery femoral vein femoral ring (usually contains a lymph node)
The last three structures are found in a sheath of deep fascia that has extended down from the abdominal wall, the femoral sheath. The sheath contains the following items, from lateral to medial: femoral artery femoral vein femoral canal (usually containing a lymph node). The femoral canal is also the site of a femoral hernia. The femoral nerve is not considered to be in the sheath.

Nerve of the Anterior Compartment of the Thigh

The femoral nerve (L2,L3,L4) supplies the muscles of the anterior compartment of the thigh, including the pectineus muscle. The psoas muscles receives its nerve supply from the lumbar plexus.

Artery of the Anterior Compartment of the Thigh

The femoral artery (1) is the principal supply to the anterior compartment of the thigh, as well as the rest of the lower limb. Its branches are: superficial iliac circumflex (3). This branch travels along the lower border of the inguinal ligament and supplies lower abdomen and upper thigh. external pudendal (2). This branch supplies superficial perineal structures. lateral femoral circumflex (5). The lateral circumflex travels around the anterior surface of the surgical neck of the femur and anastomoses with the medial circumflex. medial femoral circumflex (4). The medial circumflex travels around the posterior surface of the surgical neck of the femur. profunda femoris (6) . The deep (profunda) femoris artery descends along the attached margin of the adductor magnus muscle, giving rise to 3 perforating branches (6a-6c) superior (highest) genicular (7) The femoral artery changes its name to become the popliteal artery after it passes through the adductor hiatus.

Table of Muscles

Muscle	Origin	Insertion	Action	Nerve Supply
sartorius	anterior superior iliac spine	upper medial surface of tibial shaft	flexes, abducts, laterally rotates thigh; flexes and medially rotates leg at knee	femoral nerve
iliacus	iliac fossa	with psoas into lesser trochanter	flexes thigh; if thigh is fixed, it flexes the trunk on the thigh as in sitting up	femoral nerve
psoas major	12th thoracic vertebral body transverse process, bodies and intervertebral disks of lumbar vertebrae	lesser trochanter	same as iliacus	segmental branches from lumbar plexus
pectineus	superior ramus of pubis	upper end shaft of femur	flexes and adducts thigh	femoral nerve
rectus femoris	straight head: anterior inferior iliac spine reflected head: ilium just above the acetabulum	patella	extension of leg	femoral nerve
vastus lateralis	upper end shaft of femur	quadriceps tendon into patella	extension of leg	femoral nerve
vastus medialis	upper end shaft of femur	quadriceps tendon to patella	extension of leg	femoral nerve
vastus intermedius	shaft of femur	quadriceps tendon to patella	extension of leg	femoral nerve

Cross Section Through the Thigh

It helps sometimes to be able to examine a section of the body, in order to gain a third dimension to the region. Again, when examining a cross section through the body, you are looking up into the the section. This is the left leg so medial should be to your left as you examine it.