Bones and Joints of the Lower Limb Flashcards
What is the function of the lower limb?
Minimizing energy expenditure when standing and walking
Locomotion - walking, running, propulsion
Weight bearing - standing, control advance of the body over the foot
What are the bones of the lower limb (major)?
Pelvic/hip/innominate bone (gluteal) Femur Tibia Fibula Bones of the foot
What is another name for the pelvic bone?
Hip/innominate bone, gluteal
What are the different regions of the pelvic bone called?
Ilium, pubis, ischium
Which leg bone is medial?
Tibia
Which leg bone is lateral?
Fibula
What are the bones of the foot called?
Tarsals, metatarsals, phalanges
How many tarsals are there in the foot?
7
How many metatarsals are there in the foot?
5
How many phalanges are there in the foot?
14
What is a sesamoid bone?
Bone embedded within a tendon or muscle
What is an example of a sesamoid bone?
Knee
What forms the pelvic girdle?
Formed by two hip bones and sacrum
What does the pelvic girdle connect?
Connects lower limb to vertebral column
What forms the acetabulum?
Ischium and pubis
When does the acetabulum complete ossification?
20 yrs
What are the types of joints?
Fibrous
Cartilaginous
Synovial
What is the most stable joint?
Fibrous joints
Describe the movement of a cartilaginous joint.
Small movement
Describe the movement of synovial joints and the various classes classified according to shape.
Very mobile.
Plane, pivot, hinge, ball and socket, condylar, ellipsoid, saddle
What are the joints of the pelvis?
Sacroiliac joint and pubic symphysis
What type/s of joint is the sacroiliac joints?
Synovial anteriorly
Fibrous posteriorly
What type of joint is the pubic symphysis?
Fibrocartilaginous
What happens to the joints around the pelvis during pregnancy?
They soften due to the hormone relaxin.
What are the ligaments of the pelvis?
Sacrospinous ligament
Sacrotuberous ligament
Obturator membrane
What are the general features of the hip joint?
Ball and socket synovial joint (multiaxial)
Stable: good bony congruence/fit
Wide range of movement - circumduction and rotation
What passes through the obturator canal?
Blood vessels
What forms the hip joint?
Acetabulum and head of the femur
What are ligaments?
Thickenings of various capsules
Where is the pubofemoral ligament located?
Pubis to femur
Where is the iliofemoral ligament?
Ilium to femur
Where is the ischiofemoral ligament?
Ischium to femur
Name three main ligaments of hip/femur
Iliofemoral
Ischiofemoral
Pubofemoral
What are the arteries in the hip joint?
Obturator artery
Reniarticular artery
Medial circumflex femoral artery
Lateral circumflex femoral artery
What type of hip fractures occur?
Trochanteric (pins, plates)
Intracapsular (avascular necrosis)
What are the features of the knee joint?
Bicondylar synovial joint (condylar type)
Poor bony fit
Stability depends on ligaments and muscles
What bones make up the knee joint?
Femoral condyles
Tibial condyles and patella
What are the menisci and associated functions?
Fibrocartilaginous peripheral discs
Improve fit & reduce wear/tear
What are the joint surfaces of the knee joint?
Femoral condyles
Tibial condyles
Patella surface
Menisci (medial and lateral meniscus)
What two layers make up the joint capsule of the knee?
Synovial layer and fibrous layer
What makes up the synovial layer of the joint capsule of the knee?
Bursae
Fat pads
What are bursae?
Synovial fluid pockets
What makes up the fibrous layer of the joint capsule of the knee?
Ligaments
How does the medial meniscus differ from the lateral meniscus?
The medial meniscus is more c-shaped.
What is the name of the inflammation of bursae?
Bursitis
What does bursitis consist of?
Swelling involving fluid, blood, pus
What causes bursitis?
Injury - meniscus, bone, ligaments
Gradual - arthritis
Other - infection, gout, tumors, DVT
Name the different bursae.
Suprapatellar bursa
Prepatellar bursa
Infrapatellar bursa (superficial and deep)
What does the stability of the knee rely on?
Ligaments, muscles, tendons and menisci
What are the different types of ligaments found in the knee?
Intracapsular
Extracapsular
Capsular
What are the intracapsular ligaments?
Anterior cruciate ligament (ACL)
Posterior cruciate ligament (PCL)
What is the extracapsular ligament of the knee?
Fibular (lateral) collateral ligament (LCL)
What is the capsular ligament of the knee?
Medial collateral ligament
What does the medial collateral ligament attach to?
Medial meniscus and anterior cruciate
What tendons are found in the knee?
Patellar ligament
Popliteus tendon
Where does the ACL run from?
Anterior of tibial intercondylar eminence to lateral condyle of femur
Where does the PCL run from?
Posterior of the tibial intercondylar eminence to medial condyle of femur
What are valgus forces?
Lateral forces
What are varus forces?
Medial forces
What does the MCL prevent?
Prevents valgus forces/abduction
What does the LCL prevent?
Prevents varus forces/adduction
What is the function of the cruciate ligaments?
Prevent anterior and posterior displacement of tibia
Where is the proximal tibiofibular joint?
Outside the knee
What type of joint is the tibiofibular joint?
Synovial joint
What is the tibiofibular joint supported by?
LCL
Does the fibula have articulation with the femur?
No
What is the distal end of the fibula?
Lateral malleolus
Does the fibula have a weight bearing function?
No
What does the fibular articulate with?
Talus and tibia
In how many places is the fibula attached to the tibia?
3 places - superior and inferior via tibiofibular joints
In middle by interosseous membrane
What is the membrane called that connects the tibia and fibula?
Interosseous membrane
What is the function of the tibia?
Transfers weight from knee to ankle
What does the tibia articulate with?
Talus, femur and fibula
What are the main functions of the interosseous membrane?
Holds tibia and fibula together
Provides muscle attachments
Provides force transmission
Separates compartments
What is the ankle joint called?
Talocrural joint
What type of joint is the ankle joint?
Hinge joint
What bones are involved in the talocrural joint?
Distal ends of the tibia (medial) & fibula (lateral) with the trochlear surface of talus.
What movements occur at the talocrural joint?
Dorsiflexion and plantarflexion
Where is the capsule of the ankle joint looser and why?
Looser anteriorly, can perform more plantarflexion
Which movement is the ankle more stable in and why?
Dorsiflexion because the trochlear surface is broader anteriorly (better bony congruence)
What are the names of the lateral ligaments in the foot?
Anterior talofibular ligament
Posterior talofibular ligament
Calcaneofibular ligament
What are the seven tarsal bones?
Calcaneus, talus, cuboid, navicular, 3 cuneiforms (medial, intermediate, lateral)
How many metatarsals are there?
5
How many phalanges does the helux have?
2
What are the different regions of the phalanges called?
Distal, middle, proximal
Where does eversion and inversion occur?
Subtalar joint
What are the weight bearing points of the foot?
Tuberosity of the calcaneus
Metatarsal heads
What are the different arches of the foot?
Transverse, medial and lateral longitudinal
What is the function of the arches?
Act as shock absorbers
What maintains the arches of the foot?
Maintained by the shape of interlocking bones and ligaments
What makes up the pelvic girdle?
Hip bones and sacrum
Name what the apertures in the interosseous membrane are used for.
Aperture for anterior tibial artery/vein
Aperture for branch of fibular artery
Name the movements associated with the different surfaces of the hip, knee and ankle.
Hip: anterior flexion, posterior extension, lateral abduction, medial adduction
Knee: anterior extension, posterior flexion
Ankle: anterior dorsiflexion, posterior plantarflexion
Name the tissue layers of the lower limb.
Skin Superficial fascia (hypodermis) Deep fascia Muscle Bone
What is the morphology and function of superficial fascia?
Innermost layer of skin, mainly made from adipose tissue, contains sensory receptors.
Attaches the dermis to the underlying tissue, shock absorption, nerve and vessel passage.
Describe the morphology and function of deep fascia.
Encloses muscles of the limbs, trunk , composed of dense CT
Decreases friction, nerve and blood vessel passage, muscle attachment site, aids venous return, forms intramuscular septa
Name the different types of fascia found in the lower limb.
Fascia lata (thigh), crural fasica (leg), plantar fascia and retinaculum (foot)
What is the iliotibial band?
A lateral thickening of deep fascia that extends from the iliac crest to the lateral tibial condyle
What does the iliotibial band serve as a site of attachment for?
Tensor fascia lata (abductor) Gluteus maximus (fibres insert into band and bones)
What is iliotibial band friction syndrome?
Occurs near the knee, where the band attaches to the knee. Common in cyclists.
An irritation of the tissue due to friction causing knee pain.
What is the retinacula?
Thickening of the deep fascia that holds all the components coming into the ankle.
Where does the retinacula occur?
Regions where tendons change direction - binds tendons down to the bone (malleolus) so that they don’t bowstring & can allow tension.
Named according to compartment.
What is compartment syndrome?
Intracompartmental pressure > venous capillary pressure
What causes compartment syndrome? What are the symptoms?
Trauma (a fracture), or by overuse (excess long distance exercise)
Pain, pulselessness, paraesthesia, pallor (pale skin), paralysis
What is the lower limb nerve supply and what are its levels?
Lumbosacral plexus (L1-S4)
Name the three main nerves supplying the lower limb.
Sciatic/Posterior (tibial and common fibular, pass into leg)
Femoral (anterior)
Obturator (medial)
Which nerve supplies the anterior, medial and posterior thigh?
Anterior thigh - femoral nerve
Medial thigh - obturator nerve
Posterior thigh - tibial nerve (with one exception)
Which nerve supplies the anterior, posterior and lateral leg?
Anterior: deep fibular (peroneal) nerve
Posterior: tibial nerve
Lateral: superficial fibular (peroneal) nerve
What is cutaneous innervation?
Peripheral nerves which have branches that supply the skin (cutaneous)
When does the external iliac become the femoral artery?
As it passes under the inguinal ligament
What is the blood supply of the muscles of the thigh?
Deep femoral artery and vein
What does the femoral artery change to when it passes through the adductor hiatus/adductor magnus?
Popliteal artery (branches to the knee joint)
What supplies the knee joint?
Popliteal artery
What branches does the popliteal split into?
Anterior and posterior tibial arteries
What artery supplies the anterior leg?
Anterior tibial
What artery supplies the posterior leg?
Posterior tibial
What artery supplies the lateral compartment of the leg?
Fibular (a branch of the posterior tibial)
What artery/ies supply the foot?
Anterior tibial artery passes into the foot and is then the dorsalis pedis
Describe the movements/divisions of the posterior tibial artery as it nears the foot.
PTA runs behind the ankle joint, through the tarsal tunnel and splits into medial and lateral plantar arteries.
What arteries supply the plantar foot?
Supplied by the plantar arch, medial plantar artery and lateral plantar artery
What does the great saphenous vein drain into?
Femoral vein
What does the small saphenous vein drain into?
Popliteal vein
What causes varicose veins?
Failure of the valves, causing a pooling of blood
What veins do varicose veins usually occur in? And what conditions cause this?
Saphenous veins (superficial) Obesity, pregnancy, menopause and aging
NB: for coronary artery bypass grafts where arterial grafts are not available, they use the great saphenous vein from the leg to bypass the heart blockage
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Which rami form plexuses that innervate the limbs?
Ventral rami (except thoracic)
Describe the movement of spinal nerves.
Spinal nerves exit through the intervertebral foramina and divide into dorsal and ventral rami.
Describe the lumbosacral plexus.
Ventral rami L1-S4 innervates the lower limb
What is the lumbosacral plexus formed of?
Lumbar plexus (L1-L4) Lumbosacral trunk (part of L4 and L5 nerve roots) Sacral plexus (L4-S4)
Where does the lumbosacral plexus lie?
Within the body of the psoas major
What peripheral nerves arise from the lumbar plexus (L1-L4)?
Femoral (anterior)
Obturator (medial)
What are the peripheral nerves of the sacral plexus (L4-S4)?
Sciatic (posterior), tibial and common fibular
What levels does the superior gluteal nerve come from?
L4, L5, S1
Where does the superior gluteal nerve travel?
Exits pelvis through greater sciatic foramen, superior to the piriformis
What muscles does the superior gluteal nerve innervate?
Gluteus medius, gluteus minimus and tensor fascia lata
What is the Trendelenburg gait due to?
Damage to the superior gluteal nerve
Due to weakening of the abductors. Unable to maintain pelvis level during single leg stance.
Compensation occurs through lateral trunk flexion.
What levels does the inferior gluteal nerve come from?
L5, S1, S2
Where does the inferior gluteal nerve exit?
Exits through the greater sciatic foramen, inferior to the piriformis.
What muscle does the inferior gluteal nerve supply?
Gluteus maximus
What levels does the femoral nerve come from?
L2-L4
Describe the movement of the femoral nerve.
Descends within psoas major, posterior to the inguinal ligament.
Passes through the femoral triangle.
Courses through the anterior thigh.
What muscles does the femoral nerve supply?
Psoas major, iliacus, pectineus, muscles of anterior thigh compartment
What does the obturator nerve supply?
Obturator externus (external rotator muscle of the hip), medial compartment of thigh
Where does the obturator nerve travel?
In the psoas major, out through the obturator canal (hole in obturator membrane) and into medial compartment of the thigh
Which division of the sacral plexus is the tibial and common fibular nerve each part of?
Tibial - anterior division
Common fibular - posterior division
What levels does the sciatic nerve arise from?
L4-S3
What divisions does the sciatic nerve give arise to?
Tibial nerve - lateral/medial plantar nerves
Common fibular nerve - deep/superficial fibular nerves
What does the tibial nerve supply?
All of the posterior compartment of the thigh except for the short head of the biceps femoris (part of the hamstrings)
What supplies the short head of the biceps femoris?
Common fibular nerve
Where does the tibial nerve run?
Passes through the popliteal fossa, between the superficial and deep calf muscles.
Carries on and passes through the tarsal tunnel and into the foot where it splits into medial/lateral plantar nerves.
What muscles does the tibial nerve supply?
Posterior thigh muscles (except for short head of the biceps femoris)
Posterior superficial leg (gastrocnemius, soleus, plantaris)
Posterior deep leg (tibialis posterior, FDL, FHL)
Muscles of the foot (plantar nerves)
What does the common fibular nerve innervate?
Short head of biceps femoris
What does the superficial fibular nerve supply?
Fibular longus and fibular brevis
What does the deep fibular nerve supply?
Tibialis anterior, EDL, EHL, peroneus tertius
