Lower Limb Anatomy Flashcards
What level is the Iliac crest found at and what is this spinal level an important landmark for?
L4-L5
Site for lumber punctures
What is the origin of the Sartorius muscle?
Anterior superior Iliac Spine (ASIS)
What is the origin of the Rectus femoris muscle?
Anterior Inferior Iliac Spine (AIIS)
What is the origin of the semimembranosus muscle?
Ischial tuberosity (on ischium)
Where do the Glute muscles originate and insert?
Gluteus minimus and medius: Inserts to the anterior aspect of the greater trochanter of the femur
Gluteus maximus: inserts into the Gluteal tuberosity, found inferior to the greater trochanter, and into the Iliotibial tract
The Gluteus muscles originate from the 3 gluteal lines of the Ilium bone (Posterior, Anterior, Inferior lines)
The lesser trochanter of the femur is the insertion point for which muscle?
Iliopsoas muscle (iliacus + psoas major)
What is the function of Quadratus femoris muscle and what are its attachments?
External hip rotator - Adductor of the thigh - Stabilises femoral head in acetabulum
Origin: Ischial tuberosity
Insertion: Quadratus tuberosity (post. side of head of femur)
Where is the Greater sciatic notch located?
Between PIIS and Ischial spine
Where does the Adductor Magnus muscle insert?
Adductor tubercle
Found on distal femur on the medial aspect
What is the Linea aspera and what muscles attach to it?
Raised part of the femur found on its posterior border
Medial thigh: Adductor Magnus - Adductor brevis - Adductor longus
Anterior thigh: Vastus medialis - Vastus lateralis
Posterior thigh: Short head of biceps femoris
Where do the short and long heads of the biceps femoris originate and where do they insert?
Long head: Ischial tuberosity
Short head: Linea aspera
Insert into Lateral head of FIBULA
What is the Pes anserinus?
It is the conjoined tendons of Sartorius / Gracilis / Semitendinosus which inserts at the Proximomedial TIBIA
What does the Superior gluteal nerve supply and what is its nerve roots?
L4- S1
Supplies:
- Gluteus medius
- Gluteus minimis
- Tensor fascia lata
What are the deep lateral hip rotator muscles?
P-GO-GO-Q
Piriformis - Gemellus superior - Obturator internus - Gemellus inferior - Obturator externus - Quadratus femoris
Which nerve supplies the Gluteus Maximus?
Inferior gluteal nerve (L5-S2)
Damage to which nerve would result in a Trendelenburg gait and which muscles is involved in this?
Damage to Superior gluteal nerve
Gluteus medius is responsible for the gait when damaged or paralysed
What is a Trendelenburg gait?
Inability to abduct thigh at the hip which causes the pelvis to tilt on the contralateral side
Where does the psoas muscle originate and attach and what is it innervated by?
Originates from the Transverse processes of L1-L5
Attaches with Iliacus muscle into the Lesser Trochanter
Supplied by Femoral Nerve
Where does the Sartorius muscle originate and insert and what main action of movement is it responsible for?
Longest muscle in the body which originates from ASIS and inserts at Proximal Medial Tibia
Supplied by Femoral nerve. Responsible for crossing legs
What are the 4 main hip adductors of the thigh and what are they innervated by?
- Adductor Magnus: inferior pubic ramus to Linea aspera + adductor tubercle (distal medial femur)
- Adductor brevis: inferior pubic ramus to Linea aspera
- Adductor longus: Anterior pubic ramus to Linea aspera
- Gracillis: inferior pubic synthesis to proximal medial tibia
Supplied by Obturator nerve
Which muscles attach to the Greater Trochanter (POGGGO)?
Piriformis - Obturator internus - Gemelli - Gluteus medius - Gluteus minimus - Obturator externus
What are the Quadricep muscles and where do they insert?
Rectus femoris // Vastus lateralis // Vastus medialis // Vastus intermedialis
Combine prior to the patella at Quadriceps femoris tendon and insert into the patella continuing to insert into the Tibial tuberosity
What are the 3 muscles of the posterior thigh and what are they innervated by?
All innervated by Tibial nerve except short head of biceps femoris (peroneal nerve)
- Semitendinosus
- Long head of biceps femoris (from ischial tuberosity)
- Short head of biceps femoris (linea aspera)
- Semimembranosus (prox. ischial tuberosity)
What are the 4 compartments of the lower leg?
Anterior // Lateral // Superficial posterior // Deep posterior
What 4 muscles make up the anterior compartment of the lower leg and what movements are they responsible for?
All muscles cause dorsiflexion of the foot
- Tibialis anterior: inversion of the foot
- Extensor hallucis longus: extension of big toe
- Extensor digitorum longus: extends all toes
- Peroneus Tertius: eversion of foot
What innervates all muscles of the anterior compartment of the lower leg?
Deep peroneal nerve (L4-S1)
What are the 2 muscles of the lateral compartment of the lower leg and what are they innervated by?
- Peroneus longus (prox fibula to medial cuneiform)
- Peroneus brevis (distal fibula to tuberosity of 5th metatarsal)
Innervated by Superficial peroneal nerve (S1)
What actions is the lateral compartment of the lower leg responsible for?
Eversion of the foot
What are the muscles of the superficial posterior compartment of the lower leg (GPS) and their nerve supply?
GPS
Gastrocnemius // Plantaris (from Lat epicondyle) // Soleus
Innervated by Tibial nerve (S1)
Where do the muscles of the superficial posterior compartment of lower leg insert and what action are they responsible for?
All muscles insert into the Calcaneus
Cause Plantar flexion of the foot
What muscles make up the Deep posterior compartment of the lower leg (PFFT) and what are they innervated by?
PFFT
-Popliteus (lateral femoral epicondyle to prox tibia - internal rotation of knee and flexing)
- Flexor hallucis longus
- Flexor digitorum longus
- Tibialis posterior (inserts into navicular and medial cuneiform to invert and plantar flex)
Innervated by Posterior tibial nerve (S1-S2)
What are the articulations of the bones of the foot starting with the calcaneum?
Calcaneum articulates with the talus (medially) and cuboid (laterally).
Cuboid articulates with metatarsals 4 + 5
Talus articulates with Navicular bone which then articulates with the Cuneiform bones
Cuneiform bones articulate with metatarsals 1 + 2 + 3
The greater sciatic foramen allows passage for 6 vessels and 7 nerves. What are they?
Vessels:
Superior gluteal artery and vein // Inferior gluteal artery and vein // Internal pudendal artery and vein
Nerves:
Superior and Inferior gluteal nerves // Sciatic nerve // Pudendal nerve // Posterior femoral cutaneous nerve // Nerve to quadratus femoris // Nerve to Obturator internus
What structures emerge above and below the Piriformis muscle?
Above: Superior gluteal vessels and nerve
Below: Sciatic nerve and inferior gluteal nerve and vessels
What structures pass through the lesser sciatic foramen?
Tendon of Obturator internus // Pudendal nerve // Internal pudendal artery and vein // Nerve to obturator internus
Which structures pass through both greater and lesser sciatic foramen (PIN)?
PIN
Pudendal nerve
Internal pudendal artery
nerve to obturator internus
How many compartments are there in the thigh?
3
Anterior (4 muscles) // Medial // Posterior
What are the muscles of the anterior thigh and its innervation and blood supply?
Iliacus // Tensor fascia latae // Sartorius // quadriceps femoris
Femoral nerve
Femoral artery
What is the innervation and blood supply of the medial compartment of the thigh?
Obturator nerve
Supplied by Profunda femoris and Obturator artery
What 5 muscles make up the medial compartment of the thigh?
Adductor longus // Adductor Magnus and brevis // Gracillis / Obturator externus
What 3 muscles make up the posterior compartment of the thigh?
Semimembranosus // Semitendinosus // Biceps femoris
innervated by Sciatic nerve. Supplied by Profunda femoris artery
What is the course of arterial blood supply in the leg starting from the abdominal aorta?
AA –> L + R common iliac artery –> External iliac artery –> Common femoral artery (occurs after inguinal ligament) –> gives rise to Profunda femoris artery (supplies posterior thigh muscles + NOF + femur) AND Superficial femoral artery –> Popliteal artery –> Anterior tibial artery anteriorly AND Tibio-peroneal trunk posteriorly (gives rise to peroneal artery and posterior tibial artery) –> Anterior tibial artery continues to the ankle where it becomes Dorsalis pedis artery
Where do the superior and inferior gluteal arteries arise from?
Internal Iliac artery
Which vessel is most at risk in a posterior approach to a THR?
Inferior gluteal artery
Where can the femoral pulse be palpated?
At the mid inguinal point (midway between ASIS and pubic symphysis)
What can be found at the mid point of the inguinal ligament?
Deep inguinal ring and femoral nerve
What does the posterior tibial artery branch into at the foot?
Medial and Lateral plantar arteries
What are the 3 deep and 3 superficial branches of the femoral artery?
Superficial:
- Superficial epigastric artery
- Superficial external pudendal artery
- Superficial circumflex iliac artery
Deep:
- Profunda femoris artery
- Deep external pudendal artery
- Descending genicular artery
What is the course of the Long Saphenous vein?
Starts at 1st digit (dorsal veins merge with dorsal venous arch)
Runs anteriorly to medial malleolus and travels up the leg medially
At saphenofemoral junction, long and short saphenous merge to drain into the femoral vein (2-4cm below and lateral to pubic tubercle)
What is the course of the short saphenous vein?
Starts laterally at the 5th digit and travels posteriorly to the lateral malleolus
What is Saphena varix and how is it caused?
Reducible blueish swelling at the point of the saphenofemoral junction (can be confused for a hernia)
Caused by incompetence of the valve at the saphenofemoral junction
Which nerve runs alongside the short saphenous vein and what does it supply?
Sural nerve
Supplies sensation to the lateral aspect of the lower leg
What provides sensation to the medial leg and when can it be damaged?
Saphenous nerve
Any surgery related to the Long Saphenous vein (e.g. harvesting for CABG) can damage the nerve
What are the sciatic nerve roots?
L4-S3
What is the dermatome of the tips of toes and sole of foot?
S1
What are the divisions of the lumbosacral plexus
Anterior and Posterior divisions
Which nerve is responsible for the cremasteric reflex and what are its nerve roots?
Genitofemoral nerve (L1-2)
Also provides sensation to the upper medial thigh
What is the function of the pudendal nerve?
Supplies external genitalia and anal sphincter
(S2, 3, 4 keeps the shit off the floor)
What are the branches of the femoral nerve and its motor innervations (L2-L4)?
MIS VQ Scan for PE
MIS VQ Scan for PE
- Medial cutaneous nerve of the thigh
- Intermediate cutaneous nerve of the thigh
- Saphenous nerve
- Vastus muscles (all 3)
- Quadriceps femoris
- Sartorius
- Pectineus
Which nerve, other than femoral, has also been found to innervate the Pectineus muscle (20%)?
Obturator nerve
What is the contents of the obturator canal and when can its structures be damaged?
Obturator artery, vein and nerve
Obturator nerve can be damaged in any pelvic surgery (e.g. TURP, ovarian cystectomy)
What is the cutaneous sensory distribution of the sciatic nerve?
Entire posterior leg, gluteal region and entire lower leg EXCEPT the medial aspect of thigh
What are the muscles of the posterior thigh and what is their innervation?
Semitendinosus // Semimembranosus // Biceps femoris // Part of adductor Magnus
Innervated by the Sciatic nerve
What are the borders of the femoral triangle?
Superiorly: Inguinal ligament
Laterally: Sartorius
Medially: Adductor longus
Floor: Iliopsoas, adductor longus and Pectineus
Roof: Fascia lata and superficial fascia
What is the lymphatic drainage of the perineum and genitals?
Superficial (horizontal) inguinal lymph nodes
What is the lymphatic drainage of the lower limbs?
Deep (vertical) inguinal lymph nodes
What are the contents of the femoral triangle?
From medial to lateral
Lymph nodes - Femoral vein - Femoral artery - Femoral nerve - Lateral cutaneous nerve - Great saphenous vein - Femoral branch of the genitofemoral nerve
What are the borders of the femoral canal?
Laterally: Femoral vein
Medially: Lacunar ligament
Anteriorly: Inguinal ligament
Posteriorly: Pectineal ligament
What is the clinical significance of the femoral canal and what pathology can arise from this location?
Canal allows for the femoral vein to expand and allow for increased venous flow
However, also a site for femoral herniation with high chance of strangulation
What is the most lateral structure of the popliteal fossa?
Common Peroneal nerve
What is the most superficial structure in the popliteal fossa?
Tibial nerve
Which structure is the most medial and deep in the popliteal fossa?
Popliteal artery
Which structure is most at risk of injury in a knee dislocation or fracture?
Popliteal artery (as it is the most deep and medial structure)
Where does the psoas major muscle insert and what action is it responsible for?
Inserts into the Lesser trochanter and contracts to raise the trunk from the supine position
What does the McMurray’s test assess?
Medial meniscus (tears/injury)
How is the sensory innervation of the scrotum split?
Lateral: Genitofemoral nerve (L1-2)
Anterior + root: Ilioinguinal nerve
Posterior: Pudendal nerve (S2-4)
What is the dermatome of the posterior knee?
L3
What bones is the medial longitudinal arch of the foot comprised of?
Calcaneus // Talus // Navicular // 3 cuneiform bones // 2 medial metatarsals
Where does the medial ligament of the foot (deltoid) originate and attach?
Originates from the medial malleolus and attaches to the Navicular bones / Talus / Calcaneus
What are the 2 lateral ligaments of the foot?
Calcaneofibular ligament
Talofibular ligament
What are the lateral hip rotators?
P-GO-GO-Q?
P-GO-GO-Q
Piriformis
Gemellus superior
Obturator internus
Gemellus inferior
Obturator externs
Quadratus femoris
What are the 3 extra capsular ligaments of the hip?
Iliofemoral // Pubofemoral // Ischiofemoral
What is the blood supply of the hip joint?
Anastomosis of the medial and lateral circumflex arteries AND inferior gluteal artery
What is the cause of anterior bursitis?
Repeated flexion of the knee (e.g. builders)
Which ligament provides valgus stability to the knee and where does it attach?
Medial collateral ligament
Attaches from medial femoral epicondyle to medial tibial epicondyle
Which ligament provides varus stability to the knee and where does it attach?
Lateral collateral ligament
Attaches from lateral femoral epicondyle to fibula head
What are the attachments for the ACL and how is it tested for?
Attaches from the anterior intercondylar tibia to the lateral intercondylar femoral notch to prevent the tibia sliding anteriorly
Tested by Lackmann’s test
What is the most commonly injured ligament in a lateral malleolar sprain?
Talofibular ligament
What structures pass posterior to the medial malleolus and deep to the flexor retinaculum?
(Tom Dick and Very Nice Harry)
Tom Dick and Very Nice Harry
Tibialis posterior
Flexor digitorum longus
Posterior tibial vessels (artery +vein)
Tibial nerve
Flexor hallucis longus
What structures run anteriorly to the malleolus and deep to the extensor retinaculum?
(Tom Has Very Nice Dogs and Pigs)
Tom Has Very Nice Dogs and Pigs
Tibialis anterior
extensor Hallucis longus
Anterior tibial vessels
Anterior tibial Nerve
Extensor Digitorum longus
Peroneus Tertius
What are the branches of the femoral artery?
Do Princesses Sew Sweet Superhero Dresses
Descending genicular artery
Profunda femoris artery
Superficial epigastric artery
Superficial circumflex iliac
Superficial external pudendal
Deep external pudendal arteries
What dermatome is the dorsum of the foot?
L4
