MS Wk 5 Study Guide.pdf

5.1 Introduction to Head, Neck & Trunk baby wants to keep eyes horizontal • ex: righting rxn • adults also do this but differently • head position influences position of spine & vic eversa what is propriception? • transmit position sense, interpret info & respond consciously/unconsciously to...

5.1 Introduction to Head, Neck & Trunk baby wants to keep eyes horizontal • ex: righting rxn • adults also do this but differently • head position influences position of spine & vic eversa what is propriception? • transmit position sense, interpret info & respond consciously/unconsciously to stim through appropriate execution of posture & movement axial skeleton development baby head up right - c curve in neck & lumbar 10 y/o - more adult like adult - C spine curvature, kyphosis & thoracic, lumbar lordosis V • transfer forces • absorb forces • weight bearing UE & LE thoracic spine cervical & lumbar spine • designed for mobility & • less mob some stability • more protection of vital organs shock absorb & load • bearing lumbar: transfer weight • from thoracic/rib cage to pelvis & LE for weight bearing in gait spinal curvatures - occur for axial loading/compression • normal lumbar lordosis • anything out of norm = strain/stress on soft tissue/bones = pain/pathology spine stability • vertebral bodies = most of weight • facets help w/ weight bearing • ALL & PLL stabilize • ligaments become taut w/ movement flexion - PLL stretched, ALL slack ext - ALL stretched, PLL slack loading 80-20 standing - 80% load supported through 2 adjacent vertebra other - 20% supported by posterior elements, facets, lamina curvature deviation can affect ratio* IV Discs • respond to weight or forces on spine • protect facets for loading • restric motion @ IV segments flexion: ant compress/post stretch ext: ant stretch/post compress rest = more than 100% stand = 100% clinically: sitting with load/bent over is way more compression! most research done @ L3 flex/ext: sagittal plane (med/ lat axis) L/R sidebend: frontal plane (ant/post axis) L/R rotation: transverse plane (vertical axis) stability compromised = asymmetry/poor alignment mechanisms to correct/compensate to maintain • upright posture ex: A - post pelvic tilt (strains posterior restraints), neck trying to find horizontal (head projected forward creating strain post) overall center of pressure changed B- hands pressing against thighs Summary: • axial skeleton accepts loads to help w/ locomotion of limbs • IV discs, passive restrains, musculature = stability of spine • adaptions bc of environmental aspect, mechanical adjustments, aging • identify what are and consider mechanisms, corrective alignments/interventions always talk about the inferior facet of the top vertebrae on the sup facet of bottom vertebrae 5.2 Cervical Spine 3 components of the cervical vertebrae 1. AO: Atlanta-occipital joint 2. AA: Atlanto-axial joint 3. C2-3 and C6-7 Craniovertebral Area (0-C1) -AO joint formed by the shallow concave atlas joined by convex occipital condyles -assists in flexion and extension (nodding) -motion occurs in sagittal plane around a medial lateral axis Craniovertebral Area: C1-2 -Atlanto-axial joint (C1-2) is formed by 2 facet joints -atlas fits on the dens (C2) -primary motion is rotation Cervical Articulations (C2-3 - C6&7) -articulating surfaces at 45 degree angle -flex/ex occur in sag plane -coupling occurs in sidebending convex condyles/atlas concave AO Motion 2 degrees of freedom -flex/ex -side bending -NO rotation AO Jnt Mechanics Flex ant roll and post slide Ex post roll and ant slide AO Motion: Flex&EX Convex on concave -flex: occipital condyles roll FORWARD and glide BACK (~5 degrees) -ex: occipital condyles roll BACK and glide FORWARD AO side end & lat flex Side bending right occipital condyles roll R and glide L Left bending left occipital condyles roll L and glide R -atlas “pressed” R bw occiput and axis -very little motion for sidebend AA Motion: Rotation -50% of total rotation AA Motion ex: in R rotation the L facet 2 degrees of freedom rotation translates forward and the R facet flex/ex translates backward Median jnt= pivot jnt 2 apophyseal jnts -inf articulate facets of atlas w sup facets of axis -surfaces are generally flat=maximizes rotation AA Motion: Flex/Ex 15 degree of flex/ex total Flex atlas tilts forward (limited by transverse lig/dens) Ex atlas tilts backward (limited by ant arch) C2-C7: Cervical Flex/Ex Superior facets slide sup and ant in flex Superior facets slide inf and post in ex C2-7: Lat flex/Sidebending -ipsilat moves inf and post -contralat moves sup and ant Ex: R side bend, the left superior facet moves sup and ant while the R superior facet moves inf and post (-coupling- Producing a rotation of vertebral body to the R) C2-7: Rotation Ipsilateral facet moves inf and medial -contralateral facet moves sup and lat ex: R rotation, the L moves sup and lat while the R facet moves inf and med Summary: -Cervical spine is very mobile & stabilized by the jnt structure, ligamentous support and musculature -Head will react to various postures or variations of the spine trying to find horizontal -There is coupling motion that occurs w sidebending and rotation 5.3 Thoracic & Lumbar Spine Fxn • thoracic & lumbar help w/ weight bearing & loading • thoracic spine incorporated w/ ribcage protecting vital organs thoracic spine • rigid compared to cervical or lumbar spine bc rib attachments • attachment for muscles that act on • head • neck • UE • pelvis rib cage allows for breathing • thoracic spine fxn • protection over mobility • significant source of referred pain curvature • normal curvature is in kyphosis (40-45 degrees) • excessive kyphosis = pain/pathology thoracic spine curvature • wedge shaped vertebral bodies • 2mm higher post Thoracic spine: Anatomy & Aging • height • end plate cross sectional area • bone mass all vertebral bodies increase cranial to caudal (mainly lower levels) as we age, wedging continues & disc space narrow at multiple levels from the third decade of life thoracic spine motion • reduced extension compared to cervical/lumbar spine • ribs help w/ respiration articulations • 12 vertebrae art w/ ribs • body - larger than cerv • vertebral canal - more narrow than cerv • SP inferiorly facet articulations sup/inf art processes • - vertical/slightly forward in frontal plane - articular facets • limits flexion/ant shear motion • allows sidebend • inferior working on superior thoracic and rib art costal articulations • ex: costovertebral (ribs 2-9) costotransverse (ribs 1-10) • ligaments provide stability • assist w/ breathing (even quiet) Respiration Pump handle movement of the ribs • diameter of the chest increasing • ant aspect increases lung volume Bucket handle movement of the ribs breathe out ribs swing out • caliper movement of the ribs • widening for lung volume inspiration: ribs 1-6 elevate & increase anteroposterior diamete • ant/sup motion of handle ribs 7-10 elevate & move laterally to increase lateral dimension Rib Movement Summary 1. upper ribs: ant elevation (pump handle) = increase ant/post diameter of thoracic cavity 2. middle/lower ribs (exclude free ribs) = lat elevation (bucket handle) = increase transverse diameter of thoracic cavity 3. caliper movements = increase lateral excursion of rib cage & allow for lung volume muscles & respiration quiet inspiration • ex: diaphragm, scalenes, intercostales • diaphragm - speparates thoracic cavity & abdominal cavity • scalene ex: increase intrathoracic volume by elevating upper ribs • intercostales: in intercostal space ex: inspiration/exhalation muscles - abdominals rectus abdominal: assist w/ forced expiration through thorax flexion, depress ribs & sternum • ex: coughing, sneezing lumbar spine • 5 vertebrae • normal lordosis characteristics: • stability • mobility • support weight of head, trunk, & arms • transmit loads from upper body & through pelvis • protect spinal cord • posture daily lumbar fxn amt of lumbar flexion a day: 121x per hour average >30 degrees • ex: 5-25% work time (office, nurses, pt etc) • lumbar flexion 8-33x per hour average for >60 degree Lumbar spine: facet jts 1. superior articulating process 2. inferior articulating process 3. facet orientation changes from sagittal plane to frontal plane 4. frontal plane orientation =. restriction from anterior shear & rotation Biomechanics: thoracic & lumbar flexion Flexion inferior articular process moves ant/ • superior superior tilt & glide of vertebral body • Extension • inferior art process moves post/infer • infer tilt & glide of vertebral body Thoracic & lumbar lateral flexion lateral flexion • ipsilat inferior articular process moves inf & post • contra inferior process moves sup/ant * coupled motion of ipsi rotation toward side of lat flexion Thoracic & Lumbar rotation • ipsi inf articular process moves med • control inferior process moves lat * small movement in lumbar to assist w/ lat flexion as coupled motion Summary: thoracic is for protection weight bearing & transfer load ribs help w/ respiration facets determine motion coupling during lat flexion & rotation 5.4 Sacrum and Pelvis anatomy review • lumbar lordosis is normal • facets of L5-S1 oriented in frontal plan can impact extend of angle of L5-S1 prevents shear or ant translation of L5 Sacrum: Position Sacral ring ' forms a closed unit of pelvis -mvmnts are very small but will impact entire pelvis Sacrum: Keystone -sacrum is linked to bw axial skeleton & lower extremeties -connects to pelvic bones via SIJ *keystone of pelvis making a very stable jnt Keystone “Locks” SIJ : Pelvic RIng Consists of sacrum, two SIJ, ilium, pubis and ischium -strength of ring depends on the tight fit of sacrum wedged bw 2 halves of pelvis Pubic symphysis -is a synathrosis jnt -end of each pubic bone covered w hyaline cartilage -jnt is connected by fibrocartilagious disc and ligaments -disc strengthen by collagen fibers & attachments of rectus abdominis muscles could “give” during pregnancy or injury Sacrum: Overvier Sacrum sacral promontory also called a base -consists of 5 fused bones -sacral crest-remnant of SP’s Coccyx -series of 3-5 fused vertebra SIJ: articulate surface -source of pain in 14-25% of ppl w chronic low back pain -pain may be secondary to surrounding SIJ Trauma stuctures -pain may be from direct trauma or postural abnormalities -pain can be from instability, hypomobility and/or inflammation -can become hypermobile if it locks -lagments can be laces SIJ: Type of jnt and aging changes Childhood: synovial jnt Adult: synarthrodial jnt Surfaces change from smooth to rough & eventually fibrotic (less mobile) -articulating surfaces are bw S1-3 -tuberosity is the location of interosseous ligament Ages 60+ not able to move or manipulate Sacral Motion 3 degrees of motion 1. Anterior-posterior around a medial-lateral axis in sagittal plane 2. Abduction-adduction around an anterior-posterior axis in frontal plane 3. Medial rotation-lateral rotation around a vertical axis in a transverse plane Overall motion is small -4 degrees Sacrum: Nutation and Counternutation -occurs in the sagittal plane -nutation: promontory moves inferiorly and anteriorly while the coccyx moves posteriorly -relative ant rotation of base of sacrum relative to ilium -counternutation: promontory moves upward and posteriorly while coccyx moves anteriorly -relative post rotation of base of sacrum relative to ilium Arthrokinematics: Nutation Anterior sacrum on ilium OR Posterior ilium on sacrum Both are occurring simultaneously! Arthrokinematics: Counternutation Posterior rotation of sacrum on ilium OR Anterior rotation of ilium on sacrum Both are occurring simultaneously! Athrokinematics: Torsion -happens w walking or any rotatory motion has an oblique axis 5 Ligaments: Passive Restraints 1. Anterior Sacroiliac Ligament -considered a capsular ligament secondary to connection of be SIJ capsule -reinforces ant aspect of SIJ 2. Iliolumbar Ligament -connects 5th lumbar vertebra to ilium; innominate -blends w ant sacroiliac ligament -stablilized the L5-S1 segment in sagittal, frontal and transverse plane -reinforces ant aspect of SIJ 3. Posterior Sacroiliac Ligament -short and long portions -sup attachment to PSIS and ilium; inf attachments to lat crest of 3rd & 4th sacral segments -blend w “long” portion of lig -blends w sacrotuberous lig- (which assists w SIJ stability indirectly and resists nutation) -resists counter nutation of sacrum 4. Sacrotuberous Ligament 5. Sacrospinous Ligament -attach from ischial spines to lat/ant border of sacrum and coccyx -restricts nutation of sacrum -assists w stability of SIJ; indirectly Lumbopelvic Rhythm -When bend forward or backward it impacts pelvis and sacrum -if you want to hinge at hips, you keep straight lumbar spine Fxn: -change pelvis position, it changes lumbar lordosis Takeaway: there can be muscle activation or position of lumbar spine that can change the pelvis which then would change sacral postion Summary: -sacrum is the keystone of the pelvis that locals in the sacroiliac jnt for stability -pelvis is dependent on ligamentous structures for stability -motion of sacrum is relative to ilium 5.5 Intro to the hip Hip • base for LE & pelvis/trunk • locomotion & guidance for lower body kinematics • assist in static/dynamic postures Motions: 3 planes of motion ex: walking, running, climbing stairs sagittal: flex/ext (med-lat axis) frontal: abd/add (ant/post) transverse: IR/ER (vertical axis) Joint info • art b/w head of femur & acetabulum • diarthrodial ball & socket • 3 DOF all pass through center of femoral head (flex/ext, abd/add, ER/IR) Hip on Pelvis OCK: femur on pelvis CCK: pelvis moving on femur Hip History /Shape Norms for Hip • Flexion: 120 degrees • Ext: 20-30 degrees • Abd: 40-45 degrees • Add: 30 degrees • ER: 45-50 degrees • IR: 45 degree Acetabulum (concave) • developed by 8 but gets deeper through puberty • angled lat, inf, ant • labrum deepens the socket for stability Femur (convex) • strongest/longest bone • medial/ant to articulate w/ acetabulum • trabecular bone = high load bearing • weakness: ward triangle (osteoporotic fractures) Greater/lesser trochanter • greater trochanter: goni reference • lesser trochanter: attachment for iliopsoas Angle of Inclination: angle in frontal plane b/w femoral neck & medial side of femoral shaft • normal: 125 degrees • cox vara: < 125 dgrees increases stab shortening of limb risk for bony changes in acetabulum loss of mobility of hip • cox valga: >125 degrees promotes dislocation lengthens limb Angle of inclination can be different in body types!! • approx 125 but can vary • infants: 150 degrees then going to 125 degrees as move upright • tall: angle = valga (larger) • short: vara Femoral Torsion • rotation of bone shaft & neck • femoral neck projects 15 degrees ant to med/lat axis through femoral condyle • can see looking down shaft • optimal congruency! Angle of torsion • anteversion = greater than 10-15 degrees • retroversion = less than 10-15 degrees • normal = 15 degrees • sup view related to head/neck of femur to distal femoral condyle Anteversion • increased ant torsion • IR of femur to compensate • increase stab (shortening of ant ligaments) turn foot in to match Retroversion • decreased ant torsion • ER of femur to compensate • favors dislocation due to increased stress on ant capsul Center Edge angle • angulation of acetabulum = angle of wiberg • reference for containment of femoral head normal: 25 degrees or greater less than 20 degrees = dysplagia Summary: hip joint = convex on concave don’t development over lifespan = stability or instability in acetabulum changes in femoral or acetabular torsion leading to compensation turn foot out 5.6 Hip Biomechanics Hip Fxn -support wt of head, arms, & trunk during static erect posture -support wt of the head, arms & trunk during dynamic activities like: ambulation, running & stair climbing. -walking: hip supports 1.3 to 5.8 times BW -running: hip supports 4.5 times BW Hip Joint Movements: Planes and Axes -Flex & ext move via spin w a medial-lateral axis ABD & ADD move in frontal plane w an anteriorposterior axis IR & EX occur in transverse plane with a longitudinal axis Arthrokinematics: Hip Flexion and Extension 1. Hip flex is a sup/ant roll with a post spin 2. Hip ext is a post roll with an ant spin Arthrokinematics: Hip Abduction and Adduction ABD is a lat/sup roll & inf slide ADD is a med/inf roll & sup slide Arthrokinematics: Hip Internal and External Rotation IR is a med roll & post slide ER is a lat roll and ant slide Arthrokinematics: Close Chain 1. ABD/ADD of hip will cause pelvic tilt 2. Pelvic tilt occurs normally during gait but will be more noticeable w weakness of gluteus medius First Class Lever -hip abductor is a first-class lever during single leg stance -hip joint is the fulcrum -gravity & body wt on one end while the muscle is the effort - fxn of hip abductors is to maintain a level pelvis Trendelenberg Sign 1. If gluteus medius is weak the opposite side of the pelvis will drop during unilateral stance 2. This is why we provide an assistive device on the contralateral side -there is now a force platform for the pelvis to remain level Summary • hip arthrokinematics follow the convex on concave rule in open chain kinematics • in close chain the pelvis moves on a stable femur and is dependent on surrounding musculature 5.7 Hip Capsule & Ligaments Passive restraints • hip capsule • acetabular labrum • ligaments Extra Articulular Ligaments 1. Iliofemoral ligament • inferior (med) portion, superior (lat) portion making a Y • strongest ligament in the body • superior-laterally & blends w/ iliopsoas • resist hip ext clinical application 1. y ligament used w/ paraplegics bc limits hip extension 2. COG moved posterior to axis b/c shift of UE 2. pubofemoral ligament • blends w/ inf band of iliofemoral lig & pectinueus • inferior/medial • taut w. hip abd & ext & some ER 3. Ishciofemoral • winds post around femur • attaches ant, some near apex of greater trochanter for strengthening capsule • taut in full IR & ext • superior fibers taut in full add Summary strong ligament reinforce hip capsule provide hip stability 5.8 Hip Muscles and Prime Movers Muscles: Hip Flexors Iliopsoas -comprised of iliacus & psoas major -the most powerful of hip flexors Pectineus -an adductor, flexor & internal rotator of the hip Rectus femoris -combines mvmnts of flex at the hip & ext at knee Muscles: Hip Flex TFL -assis in flexing, ABD & IR of hip Sartorius -responsible for flex, ABD & ER of hip -some degree of knee Flex Prime Movers Glute Max -largest & most important hip extensors & ER of hip Glut Med -main ABDuctor of hip - ant portion works to flex, ABD & IR hip -post portion extends and ER hip Glut Min -major IR of femur Muscle Line of Pull and Leverage: Piriformis - external rotator of hip at less than 60° of hip flex -At 90° of hip flexion, piriformis reverses its muscle action becoming an internal rotator & abductor of hip Muscle Line of Pull and Leverage: Adductors Consists of adductor magnus, longus, & brevis, and gracilis -When hip is flexed adductors work as extensors -When hip is extended, the adductors are in a position to flex the hip Muscles: Hamstrings Consists of biceps femoris, semimembranosus & semitendinosus A. biceps femoris, extends hip, flexes knee & externally rotates tibia B. semimembranosus & semitendinosus extend hip, flex knee & internally rotate tibia Summary • The muscles surrounding the hip help to stabilize and can assist in multiple directions of movement • Some muscles change action as a response to positions of the pelvis and lower extremities