2. Posterior intramuscular septum
Femur
Iliotibial
tract
Medial intramuscular
septum
Lateral
intramuscular
septum
Thigh has posterior, anterior, and medial compartments.
Thigh is divided by Lateral, medial, and posterior intramuscular septa.
Posterior intramuscular
septum
Sciatic n.
Plate 493

3. Medial intramuscular septum Femur Femoral artery Lateral intramuscular
Fascia lata encircles all of the muscles of the thigh
Medial compartment is the adductor compartment
Anterior compartment is the extensor compartment of the thigh (kicking muscles)
Great
saphenous
vein
Sciatic nerve
Posterior
intramuscular
septum
Fascia lata

4. L1 L3 L4 L5 S1
Plate 470

5. Saphenous opening Femoral v. Lateral cutaneous n. of thigh
Great saphenous v.
Great saphenous vein – Vein that runs down length of medial aspect of thigh. It crosses knee on posterior aspect.
Saphenous opening – opening in the fascia lata where the great saphenous vein dives deep to join the femoral vein
Great saphenous v.
Saphenous n.
Superficial fibular n.
Plate 471

6. Great saphenous v. Plate 473
Superficial inguinal nodes – lymph nodes that lie along great saphenous vein and inguinal ligament superficial to the fascia lata that drain:
The external genetalia (except for the testicle which goes to aortic nodes)
Inferior portion of anal canal below pectinate line
Anterior abdominal wall inferior to the umbilicus (superior to umbilicus drains into the axillary nodes
All of the superficial part of lower limb
A fissure in the anal canal or a lesion on dorsum of foot, for example, could cause these nodes to enlarge
Plate 473

7. Inguinal ligament Pectineus m. Femoral n. Adductor longus m.
Deep inguinal nodes – lymph nodes that lie medial to the femoral vein and receive lymph from:
Deep structures and muscles of the lower limb
Superficial inguinal nodes
Sartorius m.
Femoral a.
Great saphenous v.
Plate 473

8. Iliopsoas m. Tensor fascia lata m. Pectineus m. Adductor longus m.
Gracilis m.
Rectus femoris m.
Sartorius m.
Muscles of the anterior extensor compartment are sartorius and quadricepts (may incldue psoas and articularis genu):
Sartorius muscle – means “tailor”
Origin: laterally (at ASIS – not mentioned in lecture)
Insertion: tibia
Action: “helps tailors sit indian style:”
Lateral rotation of the hip
Flexion of the knee
Flexion of the hip
Four quadriceps muscles that insert into a common quadriceps tendon:
Vastus medialis – medial most muscle; origin from femur; only flexes knee joint
Vastus lateralis – lateral most muscle; origin on femur; only flexes knee joint
Rectus femoris – in the middle between the two vasti muscles; origin at anterior inferior iliac spine, so also a week flexor of hip joint (Iliopsoas is the powerful hip flexor)
Vastus intermedius – deep to rectus femoris; orgin on femur (viewable on next slide); only flexes knee joint
Patella – a sesamoid bone embedded in the common quadriceps tendon that forms the knee cap, which serves as a fulcrum of the knee joint
Ligamentum patella – the continuation of the common quadriceps tendon after the patella that inserts into the tibial tuberosity
Patella creates a fulcrum at the knee joint
Tensor fascia lata may be considered with anterior group but it gets its nerve supply from the superior gluteal nerve
Vastus lateralis m.
Vastus medialis m.
Plate 480

9. Pectineus m. Adductor longus m. Iliopsoas m. (cut) Gracilis m.
Vastus intermedius m.
Rectus femoris is cut to reveal vastus intermedius right under rectus femoris
Vastus lateralis m.
Vastus
medialis m.
Plate 480

10. Iliopsoas m.
Tensor fascia lata m.
Pectineus m.
Adductor longus m.
Gracilis m.
Rectus femoris m.
Sartorius m.
Vastus lateralis m.
Vastus medialis m.
Plate 480

11. Psoas major m. Iliacus m. Iliopsoas m. Plate 484
Illustrates how iliopsoas is formed and attaches to lesser trochanter
Iliacus m.
Iliopsoas m.
Plate 484

12. Pectineus m. Adductor longus m. Iliopsoas m. (cut) Gracilis m.
Vastus intermedius m.
Medial compartment of the thigh (primarily supplied by the obturator nerve, which divides into an anterior and posterior division):
Gracilis muscle – (L. “slender”) runs down the medial side of thigh
Origin: Pubis
Insertion: proximal end of tibia body
Action: Adduction of the lower limb (weakest member of adductor group)
Frequently harvested for transplants
Pectineus m. -- dif
Insertion: Shaft of femur (mostly linea aspera)
Action: Hip adduction
Innervation: obturrator n. and femoral n.
Adductor longus
Action Hip Adduction
Vastus lateralis m.
Vastus
medialis m.
Plate 480

13. Obturator externus m. Obturator n. Adductor magnus m. Adductor
Adductor brevis – deep to pectineus,
Origin: External aspect of obturrator foramen and obturator membrane
Insertion: Greater trochanter
Action: weak adductor
Sandwiched by the anterior and posterior division of the obturrator nerve
Red circle is the adductor hiatus (see next slide)
Adductor
brevis m.
Adductor longus
m. (cut)
Adductor magnus m.
Plate 527

14. Obturator externus m. Pectineus m. (cut) Adductor magnus m. Adductor
(Everything taken off except adductor Magnus.)
Adductor Magnus – fills in medial side of femur; part of it is a hamstring
Origin: Inferior pubic ramus to ischial tuberosity
Insertion: proximal femur [linea aspera] down to medial condyle
Action: Adduction of thigh; extension of hip
Innervations: adductor portion by obturator nerve; hamstring portion by tibial portion of sciatic nerve
Perforating arteries – Arteries that travel from the medial compartment through a series of small holes in the adductor magnus tendon to supply the posterior compartment of the thigh
Adductor hiatus – A gap between the adductor magnus m. and the femur that allows the passage of the femoral a. and v. to the popliteal fossa where they become the popliteal a. and v.
Thus, there are two muscles in the medial compartment that receive dual innervation:
Pectineus: obturator n. and femoral n.
Adductor magnus: obturator n. and tibial n.
The three adductor muscles from superficial to deep are
Adductor longus
Adductor brevis
Adductor magnus
The only muscle of adductor compartment that can act on knee joint is gracilius, but it’s a relatively weak muscle
Adductor
brevis m. (cut)
Adductor
longus m. (cut)
Plate 481

15. Lasteral cutaneous n. of thigh Femoral n. Femoral a. Femoral v.
Iliopsoas m.
Anterior and medial compartment don’t have a clearly defined boundaries.
Femoral triangle
Borders:
Laterally bordered by sartorious
Medially bordered by adductor longus
Superiorly borded by the inguinal ligament (the bas)
The apex is where sartorious and adductor longus cross
The floor consists of iliopsoas laterally and pectineus/adductor longus medially
The roof is the fascia lata
Contents (medial to lateral):
Empty femoral canal
Femoral vein
Femoral artery
Femoral nerve
Femoral hernia – Bowel protruding through femoral canal; tends to occur in females because shape of pelvis makes opening wider
Branches:
Superficial epigastric artery – (and vein) ascend between the two layers of superficial fascia toward the umbilicus
Superficial circumflex iliac vessels
(external pudendal)
Caput medusae– engorgement of periumbilical [due to portal hypertension; blood flows through superficial eipigastric v. to femoral v. to IVC]
Greater saphenous vein – ascends over the posterior border of the medial epicondyle of the femur bone and then courses anteriorly to penetrate the fascia lata in the saphenous opening to join with the femoral vein in the femoral triangle
Sartorius m.
Adductor
longus m.
Plate 488

16. Sartorius m. (cut) Deep a. of thigh Femoral n. Femoral a. Femoral v.
Sartorious is cut
The femoral nerve gives several branches
Vasti and Sartorius, for example receive braches of femoral nerve
Sartorial canal (adductor canal or hunter’s canal) – the canal deep to the sartorius muscle that is traversed by the femoral artery and vein as they descend the leg anteriomedially from the apex of the femoral triangle contains
Femoral a.
Femoral v.
Saphenous n.
Nerve to vastus medialis
Only femoral artery and vein pass through the adductor hiatus
Saphenous nerve – a branch of the femoral that passes down the sartorial canal emerges from the canal to travel with the saphenous vein along the leg. Mainly supplies cutanous sensation to the medial leg
Saphenous n.
Rectus
femoris m.
Vastus medialis m.
Plate 488

17. Fascia lata (reflected) Great saphenous v. Plate 255
Femoral canal, artery, and vein bring out fascia from abdomenal canal
Femoral sheath – contains filmy investing fascia that surrounds femoral artery, vein, and canal. NOT the femoral nerve because it’s already outside of external transversalis fascia.
3 compartments—one for artery one for vein, and one for canal
From Book (P553):
Femoral sheath – funnel shaped fascia tube that passes deep to the inguinal ligament, lining the vascular compartment of the retro-inguinal space.
It blends in with the adventitia of the vessels
Formed by an interior prolongation of the transveralis and iliopsoas fascia from the abdomen
It does not enclose the femoral nerve because the nerve passes through the muscular compartment
Allows the femoral artery and vein to glide deep to the inguinal ligament during movements of the hip joint
Subdivided by vertical septa of extraperitoneal connective tissue into three comparments:
Lateral compartment for artery
Intermediate compartment for vein
Medial compartment for femoral canal
Allos femoral vein to expand
Contains loose CT,fat, and a few lymph vessels, and sometimes a ndoe
Femoral ring – entrance to femoral canal which has borders:
Medially: lecunar ligament
Laterally: verticle septum between the femoral canal and femoral vein
Posteriorly: superior pubic ramus covered by pectineus muscle and fascia
Anteriorly: medial part of the inguinal ligament
Great saphenous v.
Plate 255

18. Lat. cut. N. of thigh External iliac a. and v. Pectineus m.
Netter as cut hole in femoral sheath
Thus there are two layers—fasica lata and femoral sheath
Pectineus m.
Fascia lata
(reflected)
Femoral
sheath
Sartorius m.
Adductor longus m.
Plate 255

19. Femoral a. (cut) Adductor brevis m. Obturator n. Perforating aa.
Deep a. of thigh
Adductor longus m.
(cut)
Gracilis m.
Femoral artery and vein are cut
Profunda Femoris (Deep artery of the thigh) – A branch of the femoral artery just inferior to the inguinal ligament, which supplies the medial adductor compartment
Perforating arteries – branches of profunda femoris that perforate the tendon of adductor magnus to supply the posterior compartment (hamstrings)
The last perforating branch terminates the profunda femoris
Perforating arties also supply adductor magnus as they pass through
Obturator comes off internal iliac to supply the posterior compartment of the thigh as well (smaller player)
Femoral a. and v.
Plate 489

20. Perforating aa.
Biceps femoris m.
(long head)
Semitendinosus m.
Biceps femoris m.
(short head)
Semimembranosus m.
Tibial n.
Popliteal a.
Common fibular n.
Popliteal v.
Small saphenous v.
Plate 490

21. Iliopsoas m. Femoral a. (cut) Medial femoral circumflex a.
Pectineus m.
Femoral artery does not supply anything in the thigh; it is the major pipline passing through
Deep artery of the thigh supplies much of the thigh muscles in all 3 compartments
Circumflex femoral arteries – Contribute to the anastomic circulation around the hip joint
Lateral femoral circumflex – branch directly courses laterally
Descending branch of lateral circumflex femoral artery – is the blood supply to the quadriceps.
Medial femoral circumflex – branches courses medially first
Lateral femoral
circumflex a.
Deep a. of thigh
Plate 492

22. Deep a. of thigh Perforating aa. Femoral a. Popliteal a. Plate 500
Femoral artery passes through adductor hiatus to form popliteal artery that enters the leg
Popliteal a.
Plate 500

23. Pectineus m. Saphenous n. Plate 526
Saphenous nerve descends and comes out at the level of the knee and becomes a subcutaneous sensory nerve along medial leg
It does not go through adductor hiatus. It parts company with the vessels and goes superficial
Saphenous nerve goes all of the way down to the foot
Saphenous n.
Plate 526

24. Obturator externus m. Adductor brevis m. Adductor hiatus Plate 527
Obturrator nerve mainly supplies adductor (medial compartment)
Adductor brevis m.
Adductor hiatus
Plate 527

25. Gluteus medius m.(covered by gluteal fascia)
Crest of ilium
Gluteus medius m.(covered by
gluteal fascia)
Tensor fascia lata m.
Gluteus maximus m.
Biceps femoris m.
(long head)
Semitendinosus m.
Posterior view
Popliteal fossa formed by:
Superiomedially: Semimembranousis, semitendonsis,
Superiolaterally: bicepts femors
Inferior borders: gastrocnemous
Semimembranosus m.
Biceps femoris m.
(short head)
Plate 495
Common fibular n.
Gastrocnemius m.
(lateral head)
Plate 483

26. Gluteus medius m. Gluteus maximus m. Gluteus minimus m.
Superior gluteal a.
Piriformis m.
Inferior gluteal n.
Sciatic n.
Pudendal n.
Biceps femoris m.
(long head)
Sciatic nerve comes down the length of the posterior thigh
The common fibular nerve passes laterally to the popliteal fossa and closely associates with head and neck of fibula
Contained within the popliteal fossa is:
Popliteal artery, a continuation of the femoral artery
Popliteal artery gives off genicular arteriesin the fossa that provide collateral circulation along the knee joint
Popliteal vein, a precursor to the femoral vein
Short (small) Saphenous vein meets up with the popliteal vein
Tibial nerve
Short saphenous vein [originates at the 5th digit] and crosses ankle on lateral side
Great saphenous vein originates on dorsal side of the foot [near the first digit]
Post. cutaneous n.
of thigh
Semiitendinosus m.
Semimembranosus m.
Popliteal a.
Plate 490

27. Intercondylar eminence
Head of fibula
Tuberosity of tibia
Anterior border (shin)
Tibea medially
Fibula laterally
Bony (palpable) landmarks of the leg
Shin – the anterior, SQ border of the tibia
Knee joint = tibea + patella
Maleoli
Tibial tuberosity – where patellar ligament attaches (continuation of quadriceps tendon)
Fibula has head, narrow neck, and a shaft
Fibula is buried deep in muscle
Medial malleolus
Lateral malleolus
Plate 501

28. Head of fibula Soleal line Lateral malleolus Medial malleolus
Posterior view
Soleal line – diagonal ridge of bone on posterior edge of tibia. The soleus muscle takes origin here
Lateral malleolus
Medial malleolus
Plate 501

29. Interosseous membrane
True interoseus membrane connecting the two. There are openings at the proximal and distal end
Plate 502

30. Interosseous membrane
Anterior
intermuscular
septum
Interosseous membrane
Tibia
Transverse intermuscular
septum
Fibula
Crural Fascia – the fascia that surrounds the leg
The crural fasica blends with the periostium of the tibia anteriorly
Anterior and posterior intermuscular septaeattach to fibula to divide the legs into
Anterior, Lateral, and Posterior compartments
There is also a septum that separates the posterior compartment into a superficial and deep part
Posterior compartment
Posterior
intermuscular
septum
Crural fascia
Plate 510

31. Superficial posterior compartment
Anterior compartment
Tibia
Fibula
Lateral
compartment
The lateral compartment has no artery, but it does have a nerve
One compartment without an artery is the lateral (but there is a nerve)
Short saphenous vein found in the SQ tissue above posterior compartment
Deep posterior
compartment
Superficial posterior compartment
Plate 522

32. Common fibular n. Small saphenous v. Gastrocnemius Gastrocnemius m.
m. (lateral head)
Gastrocnemius m.
(medial head)
Gastrocnemious
Origin: femur
Insertion: calcaneal tendon (about midcalf)
Action: Plantar flexion, flexon of knee joint
Calcaneal tendon
Plate 504

33. Plantaris m. Soleus m. Gastrocnemius m. (cut) Tendon of plantaris m.
Soleus – found just deep to gastroc
Origin: soleal line (tibia)
Insertion: calcaneus tendon
Action: plantar flexion
Achilles (calcaneal tendon) –the combined tendon of soleus and achilles tendon
Plantaris – muscle belly crosses medially and becomes tendonous, which is used for harvest
[Origin: femur]
Insertion: calcaneus bone
Action: Flex the knee joint, plantar flex the ankle joint (neither action is significant)
When achilles ruptures there is a loud pop and there is a knot of that muscle bellies
When plantaris ruptures there is no knotting or need for repair
Plate 505

34. Tibial n. Popliteal a. Posterior tibial a. Popliteus m.
Flexor hallucis
longus m.
Flexor digitorum
longus m.
Gastrocnemius and plantaris and soleus are cut to expose the four muscles of the deep posterior compartment of the thigh (medial is left, lateral is right)
Three of the muscles have tendons that cross the medial aspect of the ankle posterior to the medial maleolus and are weakly involved in plantar flexion:
Flexor Hallucis longus – thick and fleshy powerful muscle
Origin: mainly the fibula
Insertion: plantar surface of distal phalanx of digit 1
Tibialis posterior
Origin: mainly the innerosseus membrane
Insertion:
Action:
Flexor digitorum longus
Origin: mainly the tibia
Insertion: distal phalanges of digits 2-5
At full extension, the knee joint rotates 5 degrees so it can lock and that the extensor muscles can relax because of:
Popliteaus muscle – runs on a transverse plane to cross the knee joint posteriorly
Origin: Lateral condylar portion of the femur
Insertion: Tibia above soleal line
Action: Unlocks the knee by rotating the knee joint 5 deg
The nerve supply to the entire posterior leg (superficial and deep) is tibial
The last thing that leaves the floor when you push off is the big toe
Tibialis posterior m.
Plate 506

35. Popliteal a. Anterior tibial a. Posterior tibial a. Fibular a.
When popliteal artery crosses the popliteaus muscle it divides into it’s terminal branches:
Posterior tibial artery – continues down the deep posterior compartment and crosses medial maleolus of ankle
Fubluar artery – branch of posterior tibial artery that passes laterally in the deep posterior compartment and enters muscle belly of flexor hallucis longus
Anterior tibial artery – originates in deep posterior compartment and moves into anterior compartment through gap in proximal end of interosseus membrane
There is no artery in the lateral compartment of the leg. It is supplied by perforating branches of the fibular artery that pierces the intermuscular septum
Popliteal artery supplies the muscular belly of Gastrocnemus

36. Extensor hallucis longus m.
Tibialis anterior m.
Tibia
Anterior compartment of the leg has three long muscles (medial to lateral) that will all dorsiflex that ankle joint:
Tibialis anterior – runs along lateral aspect of the shaft of the tibia
Origin: mainly the tibia
Insertion:
Action: helps in dorsiflexion, inversion
Extensor hallucis longus – buried, but can see the tendon heading to the great toe
Origin: mainly interosseus membrane
Action:
Extensor digitorum longus – has five tendons going
Origin: mainly fibula
Insertion: toes 2-5 and an the extra tendon of fibularis tertius (the inferior fibers of EDL)
Inversion – turing foot inward so weight is on little toe side (sole of foot is facing medially)
Eversion – turning foot outward so weight is on big toe (sole of foot is facing laterally)
Extensor hallucis longus m.
Extensor digitorus longus m.
Extensor retinaculum
Plate 507

37. Tibialis anterior m. Deep fibular n. Anterior tibial a.
Superficial fibular n.
In the popliteal region, the components of the sciatic nerve part in company
Common fibular nerve
Only innervates the shorthead of biceps femoris
Passes laterally towards neck of the fibula and will divide into
Superficial fibular nerve – supplies lateral compartment
Deep fibular nerve – supplies anterior compartment
Is quite superficial and prone to trauma (automobile bumper, compression from leg cast, etc.)
Compression of common fibular nerve (or damage to deep fibular branch) would give symptoms of foot drop because power plantar flexors are now unopposed
Trauma to the common fibular nerve ( or the superficail fibular nerve) would cause eversion (because inverters are lost)
Anterior tibial artery appears in anterior compartment. It will link up with the deep fibular nerve and will run parallel through anterior compartment
Artery and nerve will come down onto the dorsum of the foot
Plate 508

38. Continuation of superficial fibular nerve (it’s the cutaneus branch)
Common fibular n.
Fibularis longus m.
Gastrocnemius m.
Continuation of superficial fibular nerve
(it’s the cutaneus branch)
Superficial fibular nerve—innervated that lateral compartment and then becomes cutaneus
The two muscles in the lateral compartment originate on the shaft of the fibula and course posterior to the lateral maleuolus and instert onto the plantar surface of the foot:
Fibularis longus – more superficial and performs eversion since it attaches to the 1st metatarsal
Fibularis brevis – attaches to the 5th metatarsal bone
These muscles are plantar flexors because they are posterior to the lateral maleolus (the folcrum)
Blood supply to the of lateral compartment – small branches of the fibular artery from the posterior compartment
In summary:
3 Fibularis muscles:
Fibularis longus – attaches to the 1st metatarsal (plantar side)
Fibularis brevis – attach to the 5th metatarsal (plantar side)
Fibularis tertus – attaches to the 5th metatarsal (plantar side)
The plantar flexors include
All muscles of the deep posterior compartment of the leg except popliteal
Fibularis longus and brevis
Fibularis brevis m.
Soleus m.
Extensor retinaculum
Fibularis tertius m.
Fibular retinaculum
Plate 509

39. Common fibular n. Deep fibular n. Superficial fibular n. Plate 530
Deep fibular nerve innervates the muscles of the anterior compartment and continues to the foot
Superficial fibular nerve two muscles of the lateral compartment and then becomes sensory nerve that takes care of the distal part o f the leg and the dorsum of the foot
Plate 530