Find study materials for any course. Check these out:
Browse by school
Make your own
To login with Google, please enable popups
To login with Google, please enable popups
Don’t have an account?
To signup with Google, please enable popups
To signup with Google, please enable popups
Sign up withor
-union of three bones: ilium, pubis, and ischium
-R and L connect: pubic symphysis anteriorly
longest and strongest bone, femoral had medially
neck connects head to shaft (displaces proximal shaft femur laterally)
-distalto neck femoral shaft courses slightly medial. knees and feet closer to midline of body
slight anterior convexity
--stress along bone dissipated compression along posterior shaft and tension along anterior so this alows for greater load bearing than if straight
birth: 140-150 degrees.
adult: 125 degrees due to loading across femoral neck with walking
provides optimal alignment of joint surfaces
acquired or conenital factors
-malalignment may lead to abnormal wear ad hip dislocation
normally, femoral neck projects 10-15 degrees nterior to ML axis through the femoral condyles.
-degree of torsion=normal anteversion
--affords optimal alignment and jont congruence (see red dots)
greater than 15 degrees
-infant typically born with 30 degrees femoral anteversion (usually decreases to 15 degrees by age 6)
may be associated with: congenital dislocation, marked joint incongruence, increased wear articular cartilage, abnormal gait pattern (in-toeing)
walking pattern with excssive hip internal rotation
-apparent compensatory mechanism used to guide excessively anteverted head more directly into acetabulum
-over time, may develop contracture of hip IR muscles so reducing hip ER ROM
-structual compensation tibia
very dense and unyielding, withstand large external loads
-thick outer shell of lower femoral neck and entire shaft
-tends to resist stress
3-dimensional lattice of trabeculae.
--tends to absorb stress
--forms along lines of stress
--spongy trabecular networks (medial nd arcuate)
between medial trabecular system and media accessory system
0in areach of lower neck of femur
forms 2/3 of perefect sphere.
-prominent pit or fovea
entire surface of femoral head covered with articular cartilage except for region of fovea
--thickest in broad region above and anterior to fovea.
runs between transverse acetabular ligament and fovea of femoral head
-tubular sheath of synovial lined connective tissue
-carries small branch obturator artery (minima, major: arteries course through capsule)
blends with transverse acetabular ligament
-deepens concavity of socket and adds stability
forces are also transferred to SI and pubic symphysis - hypomobility at these joints may cause increase wear at hip
(not a lot of movement at SI joint and pubic symphysis may cause more wear at hip)
projects laterally from pelvis with varying amount of inferior and anterior tilt.
-malaligned acetabulum does not adequately cover femoral head (chronic dislocation and OA)
angle of wiberg
-extent to which acetabulum covers femoral head in frontal plane (35-40 degree)
-provides protective shelf over the femoral head
-vertical alignment (smaller angle) associated with less containment of femoral head and increased risk of dislocation
describe the extent to which the acetabulum surrounds the femoral head within the horizontalplane.
-a normal acetabular aneversion angle (about 20 degrees) exposes part of the anterior side of the femoral head
-persons with excessive anteversion of both femur and acetabulum susceptible to anterior joint dislocation (especially extremes of ER)
iliofemoral, pubofemoral, ischiofemoral
--passive tension in these ligaments and in surrounding muscles limit extremes of motion
attachment ASIS and adjacent margin of acetabulum to intertrochantric line of femur
=one of the thickest and strongest ligaments of the body
-standing with hip fully extended, anterior surface of femoral head rest against ligament
passive tension in ligament important stabilizing force
-persons with paraplegia often use tension in ligament to assist with standing
attaches along anterior and inferior rim of acetabulum, superior pubic ramus and obturator membrane
-blend with fibers of medial iliofemoral
posterior and inferior acetabulum-superficial fibers spiral superiorly and laterally across posterior neck of femur to greater trochanter.
position of extension, IR, and abduction=elongates ligaments.
unique: because not associated with its position of maximal joint congruency
-->full extension of hip (about 20 degrees beyond neutral position) twists or "spirals" much of the capsular ligaments to their most taut position
-adding slight IR and abduction to full extension elongates some component of all the capsular ligaments
90 degrees flexion with moderate abduction and external rotation
=much of capsule an dligaments "unraveled" to a more slackened state
intracapsular pressure healthy hip normally less than amospheric pressure
-relativiely low pressure creates partial suction that resists distraction of hip
-extra element of stability
excpet at extremes of motion, pressures relatively low flexion and extension. even with injected to stimulate capsular swelling, pressures increase throughout greater ROM while remaining lowest mid range flexion in extension.
-ppl with capsulitis find partial flexion most comfortable
-tend to feel comfortable holding the hip in partial flexion.
- reduced intracapsular pressure decreases distention of the inflamed capsule
-over time may develop adaptive shortening of hip flexor muscles.
rotation of the pelvis (and often superimposed trunk) over relatively fixed femurs
they often occur simultaneously
-described from anatomic position
knee fully flexed- 120 degrees (squatting, tying a shoelace)
knee extended- 80 degrees (passive tension hamstrings and gracilis)
=slackens most ligaments bu stretches inferior capsule
20 degrees beyond neutral position
-knee fully flexed put hip in neutral position: passive tension rectur femoris (crosses hip and knee)
-full hip extension increases passive tension in most capsular connective tissues, especially iliofemoral lig and hip flexors
hip adducts 25 degrees beyond neutral position
-limited by interference with contralateral limb
hip IR 35 degrees from neutral position.
-in healthy young adults, IR ROM unchanged with the hip flexed or extended
lower caudal end of axial skeleton firmly attached to pelvis via SI joint
rotation of pelvis over femoral head typically changes configuration of lumbar spine
occurs as pelvis and lumbar spine rotate in the same direction
-movement maximizes angular displacement of entire trunk relative to LEs
occurs as pelvis rotates in one direction and the lumbar spine rotates in opposite direction
-important consequence of this movement is that the supralumbar trunk (portion above lumbar vertebrae) can remain essentially stationary as the pelvis rotates over the femurs
used during activities where the position of supralumbar trunk needs to be held fixed in space independent of rotation of the pelvis (walking/dancing)
-lumbar spine function as mechanical "de-coupler" allowing independent pelvis and supralumbar trunk movement
sitting upright with 90 degrees hip flexion, normal adult can achieve about 30 degrees additional pelvic-on-femoral hip flexion before being restricted by a completely extended lumbar spine.
-full anteiror tilt slackens iliofemoral ligament and elongates inferior capsule
hips can be extended about 10-20 degrees from the 90 degree sitting posture through a posterior tilt of the pelvis
-lumbar spine flexes (or flattens) as the pelvis is tilted.
-iliofemoral and iliopsoas muscle are slighlty elongated
done by hiking the iliac crest on the side of the nonsupport hip.
-if supralumbar trunk remains stationary, L-spine must bend opposite the standing foot.
-restricted to about 30 degrees: due to natural limits of lateral bending lumbar spine
iliac crest on side of non-support hip rotates forward in horizontal plane.
-lumbar spine rotates in opposite direction of rotating pelvis.
iliac crest on side of non-support hip rotates backward in horizontal plane.
-lumbar spine rotates in opposite direction of rotating pelvis
T12-L4. innervates muscles of anterior and medial thigh
-femoral and obturator nerves
L4-S4. innervates muscles of posterior and lateral hip, posterior thigh, and entire lower leg
potent hip flexor both femoral on pelvic and pelvic on femoral
iliacus: anterior tilt the pelvics, accentuate lumbar lordosis
psoas major: excellent vertical stability of lumbar spine
Primary flexor, and abductor of hip, seondary IR
-stretching tight ITB incorporate adduction and extensioni
spasticity of hip flexors, wekness of hip extensors, arthritis, confinement to a wheelchair
-limited hip extension
-disruption of normal biomechangics of standing
in normal standing: force of body weight posteiror to ML axis of hip (hip extensor torque)-prevented from further extension by passive flexor torque by stretched capsular ligaments
hip flexion contracture: line of force anterior to the hip, creating a flexion torque- gravity now is a hip flexor. active extensor torques are required by muslces (glut max)
pectineus, adductor longus, gracilis
origin: supeior and inferior pubic ramus
insertion: pectineus and add long to posterior femur. gracilis proximal tibia
adductor magnus - triangular shaped, proximal entire ischial ramus and part of tuberosity turns into anterior and posteiror heads
-fibers run more vertically and attach as tendon on adductor tubercle on medial distal femur
-often referred to as extensor head of adductor magnus
produce torques in all planes of the hip: primary action in frontal and sagittal planes
-horizontal plane actions described with IR
regardless of hip position, posterior fibers of adductor magnus are powerful hip extensors (similar to hamstrings)
-remaining adductors are flexors or extensors depending on hip position
-dual function may partially explain relatively high susceptibility to strain injury with running
glut max, hamstrings, posterior head adductor magnus
secondary: poserior fibers glut med.
slightly flexed posture: body weight displaced just anterior to ML axis of the hip
-restrained by minimal action of glut max and hamstrings
-greater activation of hamstrings, glut max relatively inactive in great flexion
primary: glut med, glut min, TFL
secondary: piriformis, sartorius
actions simi with abduction
about 20% CSA, anterior fibers flexion potential
patienet asked to stand in single-limb support over weak hip
-positive sign if pelvis drops to the side of the unsupported limb, pelvic-on-femoral adduction, compensation: lean trunk to theside of weakness
short, line of force in horizontal plane, ptimal for producing external torque
-piriformis, obturator internus, gemellus superior, infeiror, quadratus femoris, glut max, sartorius
Sign up for free and study better.
Get started today!