THIGH REGION BY GM MUWANGA The lower limb • lower limb consists of the following components: thigh leg foot • lower limb is connected to the trunk by pelvic girdle bones (i.e., hip bones) The thigh Fascial compartments of the thigh • superficial fascia is deep to the skin • superficial fascia contains: fat superficial vessels, cutaneous nerves, & superficial lymphatics Deep fascia of thigh • is also called fascia lata & surrounds all thigh muscles like an elastic sleeve • is a dense CT layer between the superficial layer & the muscles • separates groups of muscles from each other Thigh muscle compartments An anterosuperior view of a transverse section through the thigh. Note superficial & deep fascia. Superficial fascia (subcutaneous tissue) has been invaded by fat & appears as a fatty layer. The deep fascia is the whitish membrane which has sent septa up to the bone, thus dividing muscles into various compartments (A, P & M). Also note some veins & nerves that run outside the deep fascia, and some that run within the deep fascia. Thigh muscle compartments Fascia lata (contn.) • fascia lata sends 3 intermuscular septa: lateral intermuscular septum medial intermuscular septum posterior intermuscular septum • septa attach to the linea aspera of the femur Thigh muscle compartments An anterosuperior view of a transverse section through the thigh. Note superficial & deep fascia. Superficial fascia (subcutaneous tissue) has been invaded by fat & appears as a fatty layer. The deep fascia is the whitish membrane which has sent septa up to the bone, thus dividing muscles into various compartments (A, P & M). Also note some veins & nerves that run outside the deep fascia, and some that run within the deep fascia. Fascia lata (contn.) • septa thus divides the thigh into 3 muscle compartments: anterior compartment medial compartment posterior compartment Muscle compartments • muscles of anterior compartment: are all innervated by the femoral nerve act to extend knee joint & flex the hip Fascia lata (contn.) • medial or adductor compartment includes muscles that adduct the thigh • muscles are innervated by the obturator, femoral, & deep femoral nerves Fascia lata (contn.) • posterior compartment contains muscles: which extend the hip that are involved in flexing the knee • muscles innervated by the sciatic nerve Iliotibial tract • fascia lata condenses & thickens laterally to form a broad band of fibers • band called the iliotibial tract Iliotibial tract (contn.) • tract extends from the iliac tubercle to the lateral condyle of the tibia • tract receives insertions of the tensor fasciae latae & part of the gluteus maximus muscles Iliotibial tract Iliotibial tract Saphenous hiatus • also known as fossa ovalis or saphenous opening • is an opening in the fascia lata • opening filled with loose connective tissue called the cribriform fascia Saphenous hiatus (contn.) • great saphenous vein pierces the cribriform fascia to drain into the femoral vein • superficial branches of femoral artery & lymphatics also transmitted through saphenous opening Saphenous opening Femoral triangle • is a fascia space in the superior-anterior one-third of the thigh Femoral triangle (contn.) • is bounded: medially by the medial margin of the adductor longus muscle laterally by the medial margin of the sartorius muscle superiorly by the inguinal ligament Boundaries of femoral triangle Boundaries & floor of femoral triangle Femoral triangle (contn.) • floor consists of the adductor longus, pectineus, psoas tendon & iliacus • roof of the triangle is formed by the fascia lata Floor of femoral triangle Femoral triangle (contn.) • when the hip joint is actively flexed, the femoral triangle appears as a depression inferior to the inguinal ligament Femora triangle (contn.) • from lateral to medial, contents of the femoral triangle are: femoral nerve femoral artery & its branches femoral vein & tributaries • other contents = fat & lymphatics Femoral triangle (contn.) • saphenous opening is located in the upper part of the triangle • transversalis fascia & psoas fascia fuse & evaginate to form the femoral sheath below the inguinal ligament Note origin & composition of femoral sheath Femoral sheath (contn.) • sheath encloses: femoral artery femoral vein femoral canal • femoral nerve lies outside sheath on its lateral aspect Compartments within the femoral sheath. Proximal end (abdominal opening) of the femoral canal is the femoral ring. Femoral sheath (contn.) • sheath divided into 3 compartments: lateral compartment contains the femoral artery intermediate compartment contains the femoral vein medial compartment contains deep lymph nodes Compartments of retro-inguinal space & structures traversing them to enter femoral triangle Femoral sheath (contn.) • medial compartment is called the femoral canal • opens into the abdominal cavity superiorly at the femoral ring • femoral canal contains deep inguinal lymph nodes (glands of Cloquet) Femoral sheath (contn.) • femoral canal is also the site at which a loop of the gut can herniate through (femoral hernia) • femoral hernia can become strangulated & can lead to gangrene of stangulated part Anterior (extensor) compartment • contains the following muscles: sartorius quadriceps femoris psoas major Iliacus Anterior (extensor) compartment (contn.) • each of these muscles is innervated by the femoral nerve Sartorius Origin: anterior superior iliac spine Insertion: medial surface of the tibia Sartorius (contn.) • Action: abducts thigh at hip joint & laterally rotates the thigh also flexes the knee joint • muscle is the longest one in the body Sartorius • Action (contn.) muscle also responsible for our being able to place our leg in a “cross-leg” position • Innervation: femoral nerve Quadriceps femoris • consists of 4 heads, hence the name quadriceps rectus femoris vastus lateralis vastus medialis vastus intermedialis Quadriceps femoris Quadriceps femoris (contn.) (a) Rectus femoris Origin: the anterior inferior iliac spine; upper lip of the acetabulum (b) Vastus medialis Origin: the medial lip of the linea aspera Quadriceps femoris (contn.) (c) Vastus lateralis • Origin: lateral lip of the linea aspera (d) Vastus intermedius • Origin: lateral & anterior surfaces of the femur Quadriceps femoris: rectus femoris Quadriceps femoris: most of rectus femoris has been removed Quadriceps femoris: v. intermedius v. lateralis v. medialis Quadriceps femoris (contn.) • Insertion: all the 4 parts of quadriceps insert into the patella &, from here, to the tubercle of the tibia patella is thus a sesamoid bone in the tendon of quadriceps femoris Quadriceps femoris (contn.) • Action: extension & stabilization of knee joint rectus femoris also a weak flexor of the hip joint • Innervation: femoral nerve Psoas major Origin: transverse processes of lumbar vertebrae Insertion: lesser trochanter of femur along with iliacus muscle via the iliopsoas tendon Psoas major (contn.) • Action: in the lower limb it to flexes the hip joint in trunk, flexes & laterally bends the lumbar vertebral column • Innervation: femoral nerve Iliacus (contn.) Origin: iliac fossa, iliac crest as well as the ala of the sacrum Insertion: lesser trochanter of femur with psoas major muscle via the iliopsoas tendon Iliacus (contn.) • Action: • has the same action as the psoas major muscle • Innervation: femoral nerve Tensor fasciae latae • muscle does not belong to anterior compartment • however, it assists muscles of this compartment in: extending knee joint flexing hip joint Tensor fasciae latae (contn.) • Origin: anterior iliac crest outer lip anterior border of ilium outer surface of anterior superior iliac spine Tensor fasciae latae • Insertion: between the two layers of the iliotibial band, about one-third of the way down Tensor fasciae latae (contn.) Action: tenses fascia lata i.e., the iliotibial tract moves forward in extension & backward in flexion but is tense in both positions flexes hip joint Tensor fasciae latae (contn.) • Action (contn.): abducts & medially rotates thigh stabilizes knee joint in extension • Innervation: superior gluteal nerve Nerves of the anterior compartment • is innervated by femoral nerve which has: muscular branches anterior & lateral femoral cutaneous branches a saphenous nerve branch Note muscular branches of femoral nerve Note anterior & lateral femoral cutaneous nerves Note branches of lateral cutaneous nerve Note course of lateral cutaneous nerve and territory of skin it is responsible for Some clinical aspect • lateral femoral cutaneous nerve enters the thigh just inferior to the inguinal ligament • an underwear which has a tight-fitting waist- band may compress the nerve at this point Some clinical aspect (contn.) • compression of the nerve results in paraesthesia (altered sensation). This includes: feeling of pin pricks having burning sensation feeling sharp pain Saphenous nerve: • travels along with great saphenous vein • continues anterior to medial malleolus at the ankle joint • here it supplies articular branches to ankle joint Territory of skin innervated by saphenous nerve * Note point where saphenous nerve pierces deep fascia to reach superficial fascia & hence skin* Note saphenous nerve & muscular branches of femoral nerve Saphenous nerve (contn.) • nerve innervates skin along medial side of the foot • innervation extends as far anteriorly as the head of the first metatarsal Saphenous nerve Adductor canal • extends: superiorly to the apex of the femoral triangle inferiorly