Muscles, Osteofascial Compartments, Vessels, and Nerves of the Lower Limb

Home , Leg, Medial plantar artery, Perforating arteries, Popliteus muscle

Muscles, osteofascial compartments, vessels, and nerves of the lower limb Institute of Anatomy, First Faculty of Medicine Paul Mozdziak Visiting Professor Muscle is Important Regional Anatomy Surface Anatomy General Structure of Muscle-Review Overview of muscle groups • Muscles of the hip joint (3 groups) • Thigh muscles (3 groups) • Muscles of the leg (3 groups) • Muscles of the foot (2 groups) Muscles of the hip joint (musculi coxae)

• Anterior group (flexors) • Posterior group: - gluteal (superficial) - pelvitrochanteric (deep) Muscles of the hip joint (musculi coxae) • Anterior group muscles: -iliacus -psoas major -(psoas minor) • Function: flexors

• Innervation: lumbar plexus (Th12 - L4)

Muscles of the hip joint (musculi coxae)

• Posterior group muscles – gluteal group - gluteus maximus - gluteus medius-abduction - gluteus minimus-abduction - tensor fasciae latae • Function: abductors, extensors, rotators • Innervation: sacral plexus (L4 - S2), directly or via gluteal nerves

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Muscles of the hip joint (musculi coxae)

• Posterior group muscles - deep (aka. pelvitrochanteric) muscles - piriformis - mm. gemelli (superior and inferior) - obturator internus (tendon - landmark) - quadratus femoris • Function (aka): small lateral rotators • Innervation: sacral plexus (L4 - S2)

Thigh muscles (musculi femoris) • Ventral (anterior) group (quadriceps, sartorius - knee extensors) • Medial group (adductors) • Posterior (dorsal) group (knee flexors)

Thigh muscles (musculi femoris) • Ventral (anterior) group - m. sartorius - tailor’s muscle - quadriceps femoris (4 heads): rectus femoris vastus medialis, intermedius, lateralis • Innervation: femoral nerve (L2 - L4)

Thigh muscles (musculi femoris)

• Medial group muscles (inner thigh): - pectineus - gracilis - adductor longus, brevis, magnus - obturatorius externus • Innervation: obturator nerve (L2 - L4); pectineus and add. magnus bineural

Thigh muscles (musculi femoris)

• Posterior group muscles (hamstring): - biceps femoris - semitendinosus - semimembranosus

• Innervation: sciatic nerve (n. ischiadicus, L4 - S2)

Leg muscles (musculi cruris) • Anterior group (digit and foot extensors and foot supinators) • Lateral group (supplemental foot flexors and pronators) • Dorsal (calf) group (foot and digit flexors)

• Tough fascial compartments - compartment syndrome!

Leg muscles (musculi cruris)

• Anterior group - tibialis anterior - extensor hallucis longus - extensor digitorum longus • Innervation: deep peroneal nerve (n. peronaeus profundus, L4 - S1)

Leg muscles (musculi cruris)

• Lateral group - peronaeus longus - peronaeus brevis • Inervation: n. peronaeus superficialis (L5 - S1)

Leg muscles (musculi cruris)

• Posterior group - superficial layer: - triceps surae, - plantaris – deep layer: - popliteus - tibialis posterior - flexor digitorum longus - flexor hallucis longus • Innervation: n. tibialis (L4 - S2)

Tight heel cord

• Clinically important that gastrocnemius crosses the knee joint • Soleus does not cross the knee joint • Can be used to determine the cause of a tight knee cord • Silfverskiöld test – Ankle Joint – Flex Knee Relaxes Gastrocnemius – If more dorsiflexion of ankle is possible with knee flexed, cause of tightness is gastrocnemius – If no change in dorsiflexion regardless of position of knee, soleus is responsible Silfverskiöld test

Foot muscles (musculi pedis)

• Plantar muscles: - muscles of the big toe (medial compartment) - muscles of the little toe (lateral compartment) - central compartment - mm. interossei Inervation: n. plantaris medialis et lateralis via n. tibialis (S1-S2) • Muscles of the dorsum of the foot (extensors) - ext. digitorum brevis and ext. hallucis brevis Inervation: n. peronaeus profundus (L4-S1)

Foot muscles (musculi pedis) - medial (big toe) compartment - • M. abductor hallucis • M. flexor hallucis brevis • M. adductor hallucis Foot muscles (musculi pedis) - lateral (little toe) compartment -

• M. abductor digiti minimi • M. flexor digiti minimi brevis • M. opponens digiti minimi Foot muscles (musculi pedis) - central compartment -

• M. flexor digitorum brevis • Mm. lumbricales • M. quadratus plantae

Foot muscles (musculi pedis) - musculi interossei -

• Mm. interossei plantares (3 ; 3., 4., 5. toe) • Mm. interossei dorsales (4; axis = 2. toe) • M. quadratus plantae Plantar Dorsal Foot Arch Factors Affecting The Arches Supporting Foot Arch

• Foot arch Medial is supported by ligaments – Staples • Short Plantar • Long Plantar • Spring Ligament Muscles Supporting the Medial Foot Arch • Longitudinal muscles (“tie beam”): - flexor digitorum longus-Medial portion - flexor hallucis longus - abductor and flexor hallucis brevis Muscles Supporting the Medial Foot Arch

• Tibialis Anterior • Tibialis Posterior Lateral Longitudinal • Tie Beams – Abductor Digiti minimmi, Flexor Digitii minimmi – Lateral portion of Flexor Digitorum • Sling – Tendon of Peroneus Brevis – Peroneus longus—long course, underneath foot. Transverse Arch

• Tie Beams – Tendon of Peroneus longus – Tendon of Tibialis posterior • Sling – Tibialis anterior medially – Peroneus brevis and tertius laterally

• Factors that maintain the longitudinal arches also maintain the transverse arch

Coming up next time:

Vessels and nerves of the lower limb Lower limb vessels

• Arteries - femoral artery and its branches • Veins: - deep system (accompanies arteries) • Popliteal and femoral – superficial system - great and small saphenous vv. - varices, by-pass grafts • Lymphatic vessels • Embryology-Time Permitting Femoral Artery • Femoral artery is the continuation of the external iliac artery: – Begins deep to the inguinal ligament. – Enclosed within the femoral sheath • transversalis fascia anteriorly and the iliac fascia posteriorly; Femoral Artery • Superficial epigastric artery: • Passes through or close to the saphenous hiatus. • Crosses inguinal ligament toward the umbilicus. • Anastomoses with inferior epigastric artery. Femoral Artery • Superficial circumflex iliac artery: – Passes through or close to the saphenous hiatus. – Passes along inguinal ligament toward the ASIS. – Anastomoses with deep circumflex iliac artery. Femoral Artery

• External pudendal artery: – Passes through or close to the saphenous hiatus. – Passes medially toward external genitalia. Deep Femoral Artery • Medial femoral circumflex. • Lateral femoral circumflex. • Perforating arteries (3). • Descending genicular. Deep Femoral Artery

– Arises from deep side of femoral artery within femoral triangle. – Largest branch. – Passes posterior to adductor longus muscle. – Medial and lateral – Perforating arteries. Medial femoral circumflex

– Leaves femoral triangle between the iliopsoas and pectineus muscles. – Ascending branch anastomoses with inferior gluteal artery. – Transverse branch anastomoses with lateral femoral circumflex artery. – Supplies hip joint, muscles of upper thigh, gluteal region. Lateral femoral circumflex

– Ascending branch anastomoses with superior gluteal artery. – Transverse branch anastomoses with medial femoral circumflex artery. – Descending branch anastomoses with genicular arteries. – Supplies hip joint, muscles of upper thigh, gluteal region. Descending genicular • Arises in adductor canal. • Musculoarticular branch: – Part of genicular anastomosis. • Saphenous branch: – Runs with saphenous nerve. Femoral angiography

• Profunda femoris + rami perforantes I-III • Circumflexa femoris medialis et lateralis Blood supply to the posterior thigh muscles • Deep Femoral + perforating arteries • A. poplitea and anastomoses around the knee joint • Topography in the popliteal fossa:

AVeN! (from deep to superficial) Popliteal Artery • Continuation of femoral artery. • Begins at adductor hiatus. • Ends at inferior border of popliteus muscle: – Branches into anterior and posterior tibial arteries. • Most anterior structure in popliteal fossa. • A. poplitea and anastomoses around the knee • A. tibialis anterior • A. tibialis posterior et a. fibularis Posterior Tibial Artery • Terminal branch of popliteal artery. • Begins at inferior border of popliteus muscle. • Accompanied by tibial nerve. • Descends on posterior surface of tibialis posterior muscle. • Medial plantar artery. • Lateral plantar artery. Arteries of the foot - plantar view • posterior tibial artery passes behind the medial malleolus • arterial arch analogous to palmar • individual variations • lower limb ischemia in diabetes: gangrene =>amputation Anterior Tibial Artery • Terminal branch of popliteal artery: – Inferior border of popliteus muscle. • Accompanied by deep peroneal (fibular) nerve. • Anterior compartment of leg. • Branches: – Anterior tibial recurrent – Lateral malleolar artery. – Medial malleolar artery. Arteries of the foot - dorsal view

• A. dorsalis pedis • palpable between the tendons • m. extensor hallus longus • extensor digitorum longus Veins of the lower limb

• Deep system (follows the arteries). • Superficial network great and small saphenous vein – varices (in valvar insufficiency) – potentially redundant => material for by-pass (of clogged coronary arteries) – deep venous thrombosis => lung embolism Femoral vein and its tributaries Great saphenous vein Relationship of structures in Femoral Triangle under the inguinal ligament: (Clo)VAN

significance: catheterization of femoral artery and vein

Lymphatic drainage of the lower limb

• Follows the course of veins – Superficial – Medial vessels • Great saphenous vein. – Lateral Vessels • Small saphenous vein • Popliteal nodes – Deep • Fewer than superficial counterparts. • 3 main groups: – Anterior tibial, posterior tibial and peroneal. » Entering the popliteal lymph nodes. Lymphatic vessels of the lower limb • Superficial Inguinal Nodes – Below the inguinal ligament – Receive lymph from the penis, scrotum, perineum, buttock and abdominal wall. • Superficial Sub-Inguinal Nodes – Proximal section of the great saphenous vein. • Deep Sub-Inguinal Nodes – Medial aspect of the femoral vein • Knowledge of the lymphatic system is necessary to understand tumor spreading.

Nerves of the lower limb

• Thigh: - Anterior group – Femoral nerve (L2-L4) - Adductors – Obturator nerve (L2-L4) - Posterior group - sciatic (L4-S2)

Nerves of the thigh Nerves of the lower limb

• Leg: - anterior group – Deep peroneal nerve. - lateral group – Superficial peroneal nerve - posterior group – Tibial nerve.

Nerves of the leg Nerves of the lower limb • foot: - plantar muscles – n. plantaris medialis – lateralis • via n. tibialis – Extensors • Deep peroneal nerve

Embryology of the Lower Limb Embryology Development-Muscles

• Somites – L1-L5, S1-S2 – at the limb bud site

• Sequence of Events (wk5) – migration – mesoderm from somites (myotomes) migrates into the limb bud forming posterior and anterior condensations

– condensation – mesoderm condenses and differentiates into myoblasts; condensations split into recognizable muscles Bone Development • Lateral plate mesoderm (LPM) – primary ossification centers- femur and tibia • Rotation takes place as the limb extends ventrally – medial 90° rotation on the longitudinal axis – Future knee becomes ventral; extensor muscles anterior Vascular Development • Umbilical a. – Axis a. • anterior tibial • mostly regresses – Terminal plexus • (but for deep plantar arch

• External Iliac a. – femoral artery • profunda femoris a. Innervation of the Limbs • Lumbosacral Plexus - Ventral Primary Rami (L2-L5, S1-S3) • Motor Axon from the Spinal cord innervate limb tissues – Local cues guide axons – Sensory axons use motor axons for guidance Muscle groups and their nerves

• Dorsal group - extensors: -dorsal hip joint group (glutei mm. and nn.) -anterior group of the thigh (femoral n.) -anterior and lateral group of the leg (peroneal n.) -dorsum of the foot (deep peroneal n.)

• Ventral group - flexors: -posterior group of the thigh (hamstrings, sciatic n.) -medial group of thigh (adductors, obturator n.) -calf muscles (tibial nerve) -muscles of the sole of the foot (branches of tibial n.) References

• Cihák: Anatomie 1, 3 • Netter: Anatomical atlas (CD version) • Sobotta: Atlas of anatomy • Grim M, Druga R et al.: Základy anatomie 5. Anatomie krajin těla • Snell’s Clinical Anatomy • Grey’s Anatomy

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