Lecture 9: Intro to lower limb Flashcards
Name all major bones of lower limb from proximal to distal
Hip
Femur (longest in body, hip to knee)
Patella (sesamoid)
Tibia = bigger and medial, paired with fibula
Bones of foot
Hip aka
Pelvis
Innominate
Os coxa
Describe hip joint
Ball and socket
Between pelvic girdle and femur
Describe bones of foot
Tarsals —> metatarsals (5) connected to phalanges
(Proximal —>distal)
Describe knee joint
Femur, patella and tibia contribute (NOT FIBULA)
DESCRIBE joints of foot
Ankle joint = clasp = talocrural joint
Intertarsal joints
Tarsometatarsal joints
Metatarso-phalangeal joints
Interphalangeal joints = hinge joints
Describe normal lower limb posture = trunk weight
Trunk weight - centre of gravity passes close to lower limb joints over area a of support (feet) = minimize torques at major joints
Describe normal lower limb posture = valgus angle
Of the knee
Places knees under hip joints and closer to centre of gravity
= improves walking efficiency (angle of femur as runs down knee = torque created by trunk less on knee when stand on one foot)
Centre of gravity passes through hip joint = produces les torques bc perpendicular, trunk sits on column = aligned with gravity in coronal plane
Anterior to knee and ankle joints
Describe neutral pelvic positioning
Asis lines up with public tubercle in coronal plane
Describe clinical correlate of pelvic tilt
Postural abnormalities of pelvis = can impact spinal curvatures (like lumbar lordosis) and contribute to lower back pain
Anterior pelvic tile = asis anteriot to pubic tubercle, accentuates lumbar lordosis = more extension torque
Posterior pelvic tilt = pubic tubercle anterior to asis = increase flexion torque
How is lower limb musculature organized
Both regionally (tend to cross same joints) and functionally into groups of muscles with similar functions
Describe gluteal region region
Hip abduction, extension and hip lateral rotation (axial rot)
Some muscles do medially rotate tho
Describe medial thigh region
Hip adduction and extension
Describe anterior thigh region
Hip flexion, knee extension (anterior to knee and hip)
Describe posterior thigh region
Hip extension
Knee flexion (hamstrings)
Describe anterior and lateral leg region
Small group muscles
Foot dorsiflexion = pull ankle up
Foot eversion = towards outside
Foot inversion = towards isndie
Foot joints extension - extend toes
Describe posterior leg region
Knee flexion
Ankle plantarflexion (straighten foot = make parallel with bones)
Foot joints flexion
What surrounds thigh and leg
Enveloped in deep fascia (epimysium) that surrounds functional groups
Septa (walls) extend deeper to further divide the groups into separate compartments
Describe fascia lata
Broad sleeve
Encircle all thigh muscles
Helps with bio mechanics of muscles
What is facia lata continuous with
Crural fascia = big sleeve
Helps with bio mechanics of muscles
Describe purpose of septa in legs
Anchor to bone direction
Isolate muscles from each other
Describe main blood supply to free lower limb
External iliac artery and its distal branches
Hip, gluteal and medial thigh region
What also receives blood from branches of internal iliac
Hip, gluteal and medial thigh region
Describe names for external iliac - as it moves down through leg
Changes names as travels dismally past anatomical landmarks
External iliac —inguinal lig—> femoral artery —adductor hiatus—> popliteal a
(Adductor hiatus = hole through medial muscle)
Describr deep veins
Deep veins generally parallel to pairs and may be paired (2 veins for one artery)= running with (venae comitantes)
Where do deep veins drain
Ultimately into ivc
Describe dorsal venous arch
Right under foot skin
Run up leg medially or laterally
Connects to deep vein eventually
Describe small saphenous vein
Runs up laterally —> goes through hole in crural fascia then drains into popliteal
= runs along posterior leg and drains into popliteal vein posterior to knee (only to back of knee)
Describe great saphenous vein
From drosal venous arch —> runs up leg medially, to fascia latta then drains through into femoral vein
=Travels along medial leg, knee and thigh into femoral vein at saphenous opening (near inguinla region)
Describe clinical correlate for superficial venous drainage
Varicose veins = some veins have valves to prevent blood back flow - especially in lower limbs
With time = valves less efficient (incompetent) = allows blood to troll into veins and dilate then
Enlarged walls
Typically not for deep veins = bc muscles help these = avoid backflow
What do the superficial veins drain
Skin areas
Describe motor and sensory innervation to lower limb
Spinal levels l1-s5
Sciatic nerve levels
L4-s3
Where does bulk of innervation of lower limb come from
Lumbosacral plexus = l1-s4
= gives rise to some of largest and longest nerves in body (like sciatic)
Are all dermatomes the same size
Nahhhh
Sacral dermatomes become concentrically smaller around anus (s5 also coccygeal)
Describe how lower limb dermatomes develop - embryonically
L1-s5=- spiral as move down leg because of medial rotation of leg during development (from lateral = medial)
Originally feet look like hands but rotates = causes spiral banding
Describe greater pelvis
False
Superior to pelvic brim
Contains lower abd viscera
Describe lesser pelvis
True
Inferior to pelvic brim
Contains pelvic viscera = sex specific organs, rectum too
Describe sex differences in pelvic girdle shape - AMAB
Narrow and deep
Heart shaped pelvic inlet
Narrow, oblong outlet
Subpubic angle = 70dgereees
Describe sex differences in pelvic girdle shape - AFAB
Overall wide and shallow
Wide oval shaped pelvic inlet
Larger round pelvic outlet
Subpubic angle = 90-100 degrees
What bones make up pelvis
Ilium
Ischium
Pubis
All fuse to form hip bone
Describe important parts of ilium bone
Iliac wing, body
Iliac crest = superior edge iliac wing, superior border of false pelvis
Anterior superior iliac spine = asis
Anterior inferior iliac spine = aiis
Describe important parts of ischium bone
Ischial spine (attachment for ligaments)
Ischial tubersoity = sit bone
Ischial ramus = connects to inf pubic ramus
Describe important parts of pubis bone
Superior pubic ramus
Pubic tubercle =forms pubic symphysis
Inferior pubic ramus
What does ischial spine do
Separates
Greater sciatic notch and lesser sciatic notch - also will divide these into foramen
Describe obturator foramen
Between pubis and ischium kinda
Describe acetabulum
Hip joint socket
Cup part
What does sacrum have - for joint
Auricular surface = articulates with ilium at sacroiliac joint
Describe joints of pelvic girdle
= goal is to provide robust and stable base for trunk and lower limb muscles = so most of bones are fused in adults (sacral vertebrae, hip bones) or articulate via solid joints (symphysis/syndesmosis)
Describe adult acetabulum
Forms from fusion of the 3 bone s
During growth up to 12y/o (afab) or 14 y/o (amab) = spaces between them are occupied by growth plates
Usually very solid joint = cannot even see where fused
Describe lumbosacral joint
Solid = symphysis
Between l5 and s1
Describe sacroiliac joints
Anterior = synovial
Posterior = solid, syndesmosis
Describe hip joints
Synovial = ball and socket
Between femoral head and acetabulum
Describe pubic symphysis joint
Solid = symphysis
Describe sacrococcygeal joint
Solid = symphysis (fibrocartilage)
What are general functions of ligaments of pelvis
Prevent upwards tilting of distal sacrum = pull sacrum down towards hip bones (sacrotuberous and sacrospinous ligaments) and for reinforcing sacroiliac joint (all ligaments of pelvis)
Name ligaments of pelvis
Anterior sacroiliac ligaments
Posterior sacroiliac ligaments
Inguinal ligament
Sacrospinous ligament
Sacrotuberous ligament
Describe sacrospinous ligament
Sacrum to ischial spine
Describe sacrotuberous ligament
Sacrum/posterior ilium to ischial tuberosity
What do sacrotuberous and sacrospinous ligaments do
Turn greater and lesser sciatic notches —> foramina (both ligaments needed)
Also helps prevent coccyx from pushing out towards post aspect due to weight = ligaments hold onto sacrum
