Lower Limb Reading Questions Flashcards
Lower limb has 6 major regions
- Gluteal region
- Femoral region
- Knee region
- Leg region
- Ankle or talocrural region
- Foot region
Lower limbs are connected to the trunk by
the pelvic girdle - a bony ring composed of the sacrum and right and left hip bones joined anteriorly at the pubic symphysis
Gluteal region
- transitional zone between the trunk and free lower limbs
- includes the buttocks and hip region, which overlies the hip joint and greater trochanter of the femur
Femoral region
- also referred to as the thigh
- contains most of the femur, which connects hip and knee joints
Knee region
- contains distal femur, proximal tibia and fibula, patella, and joints between them
(fat-filled hollow posterior to the knee is called the popliteal fossa)
Leg region
- connects knee and ankle joints and contains tibia and fibula
- calf of leg is posterior prominence
Ankle or talocrural region
- includes narrow distal part of leg and ankle (talocrural) joint
Foot region
- distal part of lower limb, contains tarsus, metatarsus, and phalanges
- superior surface = dorsum of foot
- inferior surface = sole or plantar region
- toes = digits of foot (great toe only 2 phalanges, others have 3)
triradiate cartilage
- separates ilium, ischium, and pubis until about 15-17 years of age
- bones begin to fuse 15-17 and complete between 20 and 25
linea aspera
prominent double-edged ridge on posterior aspect of femur
femoral condyles (medial and lateral) of femur articulate with
tibial condyles to form the knee join
angle of inclination
- adult = 115 to 140 degrees (avg. 126 degrees)
- angle is less in females because of increased width between the acetabula and the greater obliquity of the shaft
torsion angle or angle of declination
- axis of head and neck of femur and transverse axis of femoral condyles intersect at axis of shaft of femur
- 7 degrees in males
- 12 degrees in females
tibia articulates with
- femoral condyles superiorly
- talus inferiorly
- fibula laterally at proximal and distal ends
medial malleolus
inferiorly directed projection from medial side of distal end of tibia
nutrient foramen
located on posterior aspect of proximal third of tibia - nutrient canal runs inferiorly from it and opens into medullary (marrow) cavity
fibula
- lies posterolateral to tibia and serves mainly as muscle attachment
- distal end forms lateral malleolus, which is more prominent and more posteriorly placed than the medial malleolus
lateral malleolus
helps hold talus in socket
interosseous membrane
connects tibia and fibula
greater sciatic foramen
- formed by sacrospinous ligament
- passageway for structures entering or leaving the pelvis
“door through which arteries and nerves leave the pelvis and enter the gluteal region”
lesser sciatic foramen
- formed by sacrotuberous ligament
- passageway for structures entering or leaving perineum
superficial layer of muscles of gluteal region
- glutei maximus, medius, and minimus
- tensor fascia latae
deep layer of muscles of gluteal region
piriformis
obturatur internus
superior and inferior gemelli
quadratus femoris
gluteal bursae
membranous sacs containing a capillary layer of synovial fluid, separate the gluteus maximus from adjacent structures
- trochanteric bursa
- ischial bursa
- gluteofemoral bursa
trochanteric bursa
separates superior part of gluteus maximus from greater trochanter of femur
ischial bursa
separates inferior part of gluteus maximus from ischial tuberosity
gluteofemoral bursa
separates the iliotibial tract from superior part proximal attachment of the vastus lateralis
posterior thigh muscles
hamstrings: semitendinosus, semimembranosus, biceps femoris long head
short head of biceps femoris - not part of hamstrings bc it crosses only the knee joint
external fibrous layer of joint capsule
- attaches proximally on hip bone to bony rim of acetabulum and transverse acetabular ligament
- distally, it attaches to femoral neck anteriorly at the intertrochanteric line and at root of greater trochanter
iliofemoral ligament
- reinforces hip joint anteriorly and superiorly
- attaches to the AIIS and acetabular rim proximally and intertrochanteric line distally
- prevents hyperextension of the hip joint during standing
pubofemoral ligament
- reinforces hip joint inferiorly and anteriorly
- arises from the obturator crest of the pubic bone and passes laterally and inferiorly to merge with the fibrous layer of joint capsule
- tightens during extension and abduction of the hip
- prevents overabduction of hip
ischiofemoral ligament
- reinforces hip joint posteriorly
- arises from the ischial part of acetabular rim and spirals superolaterally to neck of femur, medial to base of greater trochanter
arteries supplying the hip joint
- medial and lateral circumflex femoral arteries - branch of the profunda femoris artery
- main blood supply is from retinacular arteries arising as branches from the circumflex femoral arteries
- artery to the head of femur - branch of obturator artery
nerve supply of hip joint
- femoral nerve, anteriorly
- obturator nerve, inferiorly,
- superior gluteal nerve, superiorly
- nerve to quadratus femoris, posteriorly
medial circumflex femoral artery
supplied most of the blood to the head and neck of the femur
Highest point of iliac crest is at level of
IV disc between L4 and L5 vertebrae
deep fascia of thigh is called
fascia lata
iliotibial tract
- continuation of fascia lata
- aponeurosis of tensor fascia lata and gluteus maximus muscles
- extends from iliac tubercle to anterolateral tibial tubercle on lateral condyle of tibia
Saphenous opening
- gap or hiatus in fascia lata inferior to medial part of inguinal ligament
- medial margin is smooth, but superior, lateral, and inferior margins form sharp edge - falciform margin
Cribriform fascia
localized membranous layer of subcutaneous tissue that spreads over saphenous opening, enclosing it
What passes through saphenous opening and cribriform fascia
- great saphenous vein and some efferent lymphatics
- and enter femoral vein and deep inguinal lymph nodes, respectively
Crural fascia
- continuous with fascia lata and attaches to anterior and medial borders of tibia, where it is continuous with periosteum
- forms extensor retinacula
Two major superficial veins of lower limb
great and small saphenous veins
Great saphenous vein is formed by
union of dorsal digital vein of great toe and dorsal venous arch of foot
Small saphenous vein is formed by
union of dorsal digital vein of fifth digit with dorsal venous arch
Deep veins of leg flow into
Popliteal vein, which becomes the femoral vein
Lymphatic vessels accompanying the great saphenous vein end in
superficial inguinal lymph nodes
Lymphatic vessels accompanying the small saphenous vein enter
popliteal lymph nodes
Deep lymphatic vessels of leg
accompany deep veins and enter popliteal lymph nodes
Axial Line
- the line of junction of dermatomes supplied from discontinuous spinal levels
- dermatomes do not overlap at this point
Varicose veins occur in
Great saphenous vein and its tributaries
Adductor Hiatus
opening between the distal aponeurotic attachment of the adductor part of the adductor magnus and the tendon of the hamstring part
Adductor Hiatus transmits
the femoral artery and vein from the anterior compartment of the thigh to the popliteal fossa posterior to the knee
Femoral Triangle Boundaries
- Superiorly by inguinal ligament, which forms base of femoral triangle
- Medially by adductor longus
- Laterally by sartorius; the apex is where the medial border of the sartorius crosses the lateral border of the adductor longus
- Floor: iliopsoas laterally and pectineus medially
- Roof: fascia lata, cribriform fascia, subcutaneous tissue, and skin (fascia - fascia of thigh = fascia lata)
Femoral Triangle Contents
- Femoral Nerve and its terminal branches
- Femoral Artery and several of its branches (bisects tri. with vein)
- Femoral Vein and its proximal tributaries
- Femoral canal
- Deep inguinal lymph nodes and associated lymphatic vessels
Adductor Canal extends from
apex of femoral triangle, where sartorius crosses over adductor longus, to adductor hiatus in the tendon of adductor magnus
- passage for femoral artery and vein, saphenous nerve, and nerve to vastus medialis
Adductor Canal Boundaries
anteriorly and laterally: vastus medialis
posteriorly: adductor longus and adductor magnus
medially: sartorius
Femoral Nerve
Largest branch of lumbar plexus
Saphenous Nerve
- terminal cutaneous branch of femoral nerve
- descends through femoral triangle
- accompanies femoral vein and artery through adductor canal
Compartments of femoral sheath
lateral: femoral artery
intermediate: femoral vein
medial: femoral canal - smallest of the 3 compartments
Femoral Artery
- chief artery to lower limb - continuation of external iliac artery
Profunda femoris artery
- largest branch of femoral artery and chief artery to thigh
- arises from femoral artery in femoral triangle
- 3 or 4 perforating arteries
- circumflex femoral arteries are usually branches
Lateral Circumflex Femoral Artery
supplies muscles on lateral side of thigh
Femoral Vein
continuation of popliteal vein
Obturator Artery and Nerve
artery: arises from the internal iliac artery
supplies: obturator externus, pectineus, adductors of thigh, and gracilis
nerve (L2-L4): supplies adductor longs, adductor brevis, gracilis, and pectineus
Popliteal Fossa
- fat filled diamond shaped space posterior to the knee
- all important vessels and nerves from thigh to leg pass through this fossa
Popliteal Fossa Boundaries
superolaterally: biceps femoris
superomedially: semimembranosus, medial to which is semitendinosus tendon
inferolaterally: lateral head of gastrocnemius
inferomedially: medial head of gastrocnemius
posteriorly (roof): skin and popliteal fascia
floor: popliteal surface of femur, posterior capsule of knee joint, popliteus fascia covering popliteus muscle
Popliteal Fossa Contents
- termination of small saphenous vein
- popliteal artery and vein and their branches and tributaries
- tibial and common fibular nerves
- posterior cutaneous nerve of thigh
- popliteal lymph nodes and lymphatic vessels
- fat
Popliteal Fossa Fascia
- strong sheet of fascia that forms a protective covering for neurovascular structures passing from the thigh through the fossa to the leg
- continuous with fascia lata superiorly and deep fascia of leg inferiorly
- when leg extended, stretches and semimembranosus moves laterally for further protection to contents of fossa
popliteal artery
- continuation of femoral artery
- begins where femoral artery passes through adductor hiatus
- passes through popliteal fossa and ends at inferior border of popliteus by dividing into anterior and posterior tibial arteries
- five genicular branches
Genicular Arteries
- superior lateral, superior medial, middle, inferior lateral, inferior medial genicular arteries
- genicular anastomosis
muscular branches of popliteal artery supply
hamstring, gastrocnemius, soleus, and plantaris muscles
Popliteal vein formed
- at distal border of popliteus as continuation of posterior tibial veins
- becomes femoral artery superiorly
- small saphenous vein also enters popliteal vein
Sciatic nerve usually ends
at superior angle of popliteal fossa by dividing into tibial and common fibular nerves
Tibial Nerve
- medial, larger terminal branch of sciatic nerve
- most superficial of the three main central components of the popliteal fossa (van)
- while in fossa, gives branches to soleus, gastrocnemius, plantaris, and popliteus
Medial sural cutaneous nerve derived from
- tibial nerve in popliteal fossa
- joined by sural communicating branch of common fibular nerve to form sural nerve
Sural Nerve supplies
skin on posterior and lateral aspects of leg and lateral side of foot
Lateral sural cutaneous nerve is branch of
common fibular nerve that supplies skin on lateral aspect of leg
Common Fibular Nerve
- lateral, smaller terminal branch of sciatic nerve
- begins at superior angle of popliteal fossa and follows border of biceps femoris and its tendon along superolateral boundary of popliteal fossa
Most important muscle in stabilizing knee joint
quadriceps femoris, particularly the inferior fibers of vastus medialis and lateralis
Joint capsule consists of
- external fibrous layer
- internal synovial membrane that lines all internal surfaces of articular cavity not covered with articular cartilage
Knee joint capsule is stengthened by
- 5 extracapsular or capsular ligaments
- patellar ligament
- fibular collateral ligament
- tibial collateral ligament
- oblique popliteal ligament
- arcuate popliteal ligament
Intra-articular structures within the knee joint consist of
cruciate ligaments and menisci
Anterior Cruciate Ligament
- Weaker of the two ligaments
- arises from anterior intercondylar area of the tibia,
- attach to the posterior part of the medial side of lateral condyle of femur
- poor blood supply
- limits posterior rolling of femoral condyles on tibial plateau during flexion
- prevents posterior displacement of femur on tibia and hyperextension
- when joint is flexed at right angle, tibia cannot be pulled anterior because it is held by ACL
Posterior Cruciate Ligament
- stronger of the two ligaments
- arises from posterior intercondylar area of tibia
- attach to anterior part of lateral surface of medial condyle of femur
- limits anterior rolling of femoral condyles on tibial plateau during extension
- prevents anterior displacement of femur on tibia and hyperflexion
- in weight bearing,PCL main stabilizing factor for femur
Menisci of knee joint are
crescentic plates of fibrocartilage on the articular surface of tibia that deepen the surface and play a role in shock absorption
- attached to intercondylar area of tibia
Coronary ligaments are
- capsular fibers that attach the margins of the menisci to the tibial condyles
Transverse ligament of the knee joins
anterior edges of the menisci, allowing them to move together during knee movements
Medial meniscus is
- C-shaped and broader posteriorly than anteriorly
Lateral meniscus is
- nearly circular and is smaller and more freely movable than the medial meniscus
Posterior Meniscofemoral Ligament joins
lateral meniscus to the PCL and the medial femoral condyle
Subcutaneous prepatellar and Infrapatellar bursae
- located at convex surface of joint, allowing the skin to be able to move freely during knee movements
Four bursae communicate with articular cavity of knee joint
Suprapatellar bursa
Popliteus bursa
Anserine bursa
Gastrocnemius bursa
Superior tibiofibular joint is a
- plane synovial joint
- strengthened by anterior and posterior ligaments of head of fibula
Tibiofibular syndemosis (distal tibiofibular joint) is a
- compound fibrous joint
- interosseous tibiofibular ligament
- strengthened by anterior and posterior tibiofibular ligaments
Inferior Transverse Ligament
- forms a strong connection between medial and lateral melleoli and posterior wall of malleolar mortise, for the trochlea of the talus
Anterior compartment of leg (dorsiflexor compartment)
- tibilias anterior
- extensor digitorum longus
- extensor hallucis longus
- fibularis tertius
Deep fibular peroneal nerve
- one of two terminal branches of common fibular nerve
- arises between the fibularis longus and neck of fibula
- accompanies anterior tibial artery
Anterior Tibial Artery
- supplies structures in anterior compartment
- smaller, terminal branch of popliteal artery
- begins at inferior border of popliteus muscle
- ends at ankle joint, where it becomes dorsalis pedis artery
Lateral Compartment of Leg (everter compartment)
- fibularis longus
- fibularis brevis
Superficial Fibular Nerve
- terminal branch of common fibular nerve
- after supplying muscles, continues as cutaneous nerve, supplying skin on distal part of anterior surface of leg and nearly all the dorsum of the foot
Muscles of lateral compartment supplied by
- proximally: perforating branches of anterior tibial artery
- distaly: perforating branches of fibular artery
- these have accompanying veins
