Anatomy II Exam 1 PDF

Lumbar Skeleton Functions: sustaining rod, anchor for muscles and ligaments, spinal cord protection, shock absorber, etc. The curves widen BOS, increase ROM, and absorb shock and other forces Lumbar curve is lordotic Ligaments are sparse between L4 and L5 Facet/apophyseal/zygoapophyseal orientation...

Lumbar Skeleton Functions: sustaining rod, anchor for muscles and ligaments, spinal cord protection, shock absorber, etc. The curves widen BOS, increase ROM, and absorb shock and other forces Lumbar curve is lordotic Ligaments are sparse between L4 and L5 Facet/apophyseal/zygoapophyseal orientation C spine: 45 degrees transverse plane T spine: 60 degrees frontal plane L spine: 90 degrees (looks most like a cup, handle goes straight out) sagittal plane (flexion extension) -​ Mamillary process: serve as attachment sites for multifidi muscles -​ Sagittal plane orientation of lumbar spine favors sagittal plane motion at the expense of rotation in the horizontal plane. concave superior articular facet: closest with sagittal plane in upper lumbar, mid to lower lumbar they are halfway between sagittal and frontal plane convex inferior articular facet: reciprocally matches to the shape and orientation of the superior articular facets, face lateral to anterior lateral. The inferior articular facet of L5 articulates with superior articiular facet of the sacrum. L5-S1 apophyseal joints are oriented much closer to the frontal plane than other lumbar articulations. This provides and important source of anterior-posterior stability to the lumbosacral junction. SPECIAL FOCUS 9.2 Development Abnormalities of Lumbar Apophyseal Joints: At birth, the articular surfaces of the apophyseal joints in lumbar spine are oriented more to frontal plane, similar to thoracic spine. Between birth and 12 y/o, the orientation within all but the lower lumbar apophyseal joints transform to be biased towards sagittal plane. This change is governed by different rates of ossification within the articular processes. The transformation may be influenced by the developing upright posture of the child and the demands places on certain muscles such as the lumbar multifidi. Natural variations in development of lumbar apophyseal joints in childhood can create structural variations that persist into adulthood, most are minor but they can be extreme. Bilateral asymmetry exists in about 20-30% of all adult lumbar vertebrae. Extreme bilateral asymmetry can predispose a person to have premature degeneration in apophyseal joint. SPECIAL FOCUS 9.3 Cauda Equina: At birth, the spinal cord and vertebral column are the same length. After birth, the vertebral column grows at a faster rate than the spinal cord. Because of this, in the adult, the caudal end of the spinal cord terminates adjacent to the L1 vertebra. The lumbosacral spinal nerve roots must travel a great distance caudally before reaching their corresponding foraminas. As a group, the elongated nerves resemble a horse’s tail and are called cauda equina. It is a set of peripheral nerves bathed in CS fluid. Severe fracture or trauma to the lumbosacral region might damage cauda equina but spare spinal cord. Damage to the cauda equina can cause muscle paralysis, atrophy, altered sensation, and reduced reflexes, (NOT spastic or exaggerated reflexes, this would indicate spinal cord damage). Since the CE is peripheral nervous system, if severed the nerves possess the physiologic potential for regeneration. SPECIAL FOCUS 9.4 Intra-articular Structures Located Within Apophyseal Joints: Lumbar spine has two primary accessory structures: subcapsular fat pads and fibroadipose meniscoids. Subcapsular Fat pads: fill small crevices formed between capsule and underlying synovial membrane, typically at superior and inferior margins of the joint. They may extend outside the joint through very small crevices in the capsule. When fully formed, larger extracapsular fat pads within the lumbar region fill part of the space between the lamina and overlying multifidi muscles Fibro-adipose meniscoids: connective tissue found at the periphery of apophyseal joist. Range from thickenings or “pleats” of connective tissue placed along the internal surface of the joint capsule, to folds of synovium that encapsulate small fat pads, collagen fibers, and blood vessels. SPECIAL FOCUS 9.6 Some Clinical Implications Regarding the Thoracolumbar Junction: The abrupt change from thoracic spine frontal plane orientation to lumbar spine sagittal orientation can create a sagittal plane hypermobility and mechanical instability in this region. This can be seen in peopole with cerebral palsy who have weak trunk muscles. They go into marked thoracolumbar hyperextension. This collapse creates a severe hyperlordosis in the region. Another clincial example is a high incidence of traumatic paraplegia at the thoracolumbar junction. In certain high-impact accidents involving trunk flexion, the thorax experiences a high flexion torque which may concentrate an excessive hyperflexion stress at the point of transition from t spine to L. If severe enough, the stress can fracture or dislocate the bony elements and possible injure the caudal end of the spinal cord or cauda equina. Surgical fixation devices implanted to immobilize an unstable thoracolumbar junction are particularly susceptible to stress failure, compared to in other regions. SPECIAL FOCUS 9.7 Anterior Spondylolisthesis at L5-S1: Anterior spondylolisthesis describes the anterior slipping or displacement of one vertebrae relative to another. Mostly occurs at L5-S1 or L4-L5. This can be acquired after excessive stress or pathology or it can be congenital. Usually anterior spondylolisthesis is associated with a bilateral fracture or deficit through the pars articularis, a section of a lumbar vertebra midway between the superior and inferior articular processes. Caused by excessive/forceful extension of the region. Severe cases of AS may damage the cauda equina. Increased lumbar lordosis increases the normal sacrohorizontal angle, thereby increasing the anterior shear force between L5 and S1. The force vector of the erector spinae muscle that crosses L5-S1 creates an anterior shear force parallel to the superior body of the sacrum. The direction of this shear is a function of the orientation of the adjacent erector spinae fibers and the 40 degree sacrohorizontal angle. In theory, a greater muscular force increases the anterior shear at the L5-S1 junction, especially if the muscle activation exaggerates the lordosis. -​ A typical scarohorizontal angle of 40 degrees produces an anterior shear force at the L5-S1 junction equal to 64% of the superimposed body weight. Increasing lordosis increases this angle and increases the anterior shear. This is done by anteriorly tilting the pelvis -​ Several structures resist the natural anterior shearing force production at L5-S1 like intervertebral disc, capsule of apophyseal joints, anterior longitudinal ligament, iliolumbar ligament -​ Iliolumbar ligament arises from the inferior aspect of the transverse processes of L4-L5 and adjacent fibers of the quadratus lumborum muscle. This ligament provides a firm anchor between the naturally stout transverse processes of L5 and the underlying ilium and sacrum SPECIAL FOCUS 9.8: More about the Herniated Nucleus Pulposus -​ Herniations involve a posterior-lateral or posterior migration of the nucleus pulposus towards sensitive neural tissues like spinal cord or cauda equina. Herniation can also include fragments of dislodged vertebral endplates. -​ Sequestration of the herniated disc refers to the material of herniated disc being lodged in the epidural space -​ Extruded or sequestered herniatios may have better prognosis than a protruded or bulging disc -​ Macrphages help reduce pressure on neural tissues which is why sometimes surgery is not needed for a herniated disc -​ Pain associated with a degenerated disc may be from damage to the innervated periphery of the posterior annulus fibrosis, PLL, or vertebral endplates. Most of the pain is usually from the herniated disc compressing on the spinal canal: causes sciatica -​ Repetetive or chronic flexion increases likelihood of posterior disc herniation, rotation also makes it worse when combined with flexion -​ The chance of experiencing a herniated disc is greater in the morning when the nucleus contains its greatest daily water content Mechanical or Structural Factors that Favor A Herniated Nusclus Pulosus in the Lumbar Spine -​ preexisting disc degeneration with radial fissures, cracks, or tears in the posterior annulus that allow a path for the flow of nuclear material -​ Sufficiently hydrated nucleus capable of exerting high intradiscal pressure -​ Inability of the posterior annulus to resist pressure from the migrating nucleus -​ Sustained or repetitive loading applied over a flexed and rotated spine SPECIAL FOCUS 9.9: Using Knowledge of Kinesiology to Help Guide Treatment of Chronic Low Back Pain: A Selected Example Used to know if you need to do flexion exercises, extension exercises, surgery, dry needling, heat or electrical stimulation, soft tissue mobilization, manipulation, traction, joint mobilization Mobility of Lumbar Spine -​ Flexion mostly at L4-L5 and L5-S1 (most motion, also most problems in these segments) -​ For someone with stenosis you would want to give them flexion exercises, not extension - intervertebral foramen diameter - facets and nucleus pulposus migration -​ Extension of 15-20 degrees - intervertebral foramen diameter - facets close down and limit movement - nucleus pulposus migration -​ Rotation of 5-10 degrees uni- -​ LSB of 20-25 degrees uni- Facet Joint Review -​ SYNOVIAL, plane joints with fibrous capsule, articular cartilage, synovial membrane, synovial fluid -​ Meniscoid: doesn’t interfere with movement unless it gets out of place -​ Guide and restrict motion -​ NOT WEIGHTBEARING, weight goes through the body -​ Lumbar facets do end up taking more weight than facets higher in the spine which makes them more prone to degeneration or injury Lumbar Spine Facets -​ 16-20% weightbearing -​ Oriented parallel to the sagittal plane (so in sagittal plane) L2 is closest to sagittal -​ Mostly extension and flexion movement, VERY little rotation, some lateral flexion -​ Limits motion in ?????? -​ L5-S1 are in oblique orientation which is important for transitioning to the pelvis because the pelvis is very stable and the lumbar spine moves a lot so L5-S1 provides that in-between point to stabilize that area. -​ Coupled motions: LSB+Rotation, CONTRALATERAL: caused by orientation of the facets -​ Noncoupled pattern is called a locked position, do not manip using the noncoupled pattern Transverse processes of L spine project laterally, L1 and L4 are thin and tapered. L5 transverse processes are short, thick and strong. Intrinsic Back Muscles: -​ Erector Spinae Muscles group (Iliocostalis, Longissimus Spinalis): gross movers -​ Common origin: broad tendon arising from iliac crest, posterior sacrum, sacroiliac ligaments, inferior lumbar and sacral spinous processes -​ Deep Layer: Transversospinalis Muscle Group (important for stability, not so much gross movement) - Spemispinalis: cross ~6 levels (assists with movement the most out of the 3)  -Rotatores: cross 1-2 levels (assists with movement the least) - Multifidus: cross 2-4 levels (in between for gross movement) Prime stabilizer for low back and quickest to atrophy after a back injury. If it is chronic the multifidus is replaced with fat (not good) Ligaments: -​ Interspinous Ligament -​ Supraspinous Ligament -​ Posterior Longitudinal Ligament -​ Anterior Longitudinal Ligament: restricts excessive extension -​ Ligamentum Flavum: elastic because of elastin and has attachments segment to segment, helps maintain pressure and position of the discs. As you age you lose the elastin and becomes for fibrotic and can cause disc issues -​ Intertransverse ligament Intervertebral Discs+Vertebra= Interbody Joints=Intervertebral symphysis -​ Synchondrosis (attached by cartilage) -​ Vertebral endplate where it attaches -​ 20-30% of the height of spine -​ Functions: bear and distribute loads, hydrostatic pressure distributor, allow motion, multi axial, multiple DoF, restrain excessive motion/stabilize Disc Structure -​ Nucleus pulposus - Gelatinous mass, 70-90% water - directly in center of disc EXCEPT in lumbar it is more posterior, disc herniations are mostly posterior in lumbar spine - allows uniform distribution of pressure within disc - Annulus Fibrosis - rings of fibrocartilage arranged in criss-cross arrangement to resist compression, bending, shear, and torsion in nearly every direction - allows bulging, radial expansion - attached to cartilaginous endplates - only OUTER rings contain blood vessels for nutrition - More than 90% of herniated discs occur at L4-L5 or the L5-S1 disc space - imbibing: nutrition from fluid, get more when laying down Kinematics of Lumbar Spine -​ 40-50 degrees of lordosis -​ 3 DoF -​ Sagittal plane movement: flexion and extension -​ When flexing the lumbar spine the compression forces between vertebrae shift AWAY from the apophyseal joints and TOWARD the disc and vertebral bodies  -​ Relative to anatomical position, flexion increases the diameter of the intervertebral foramen by 19% so lumbar flexion can be used therapeutically as a way to temporarily reduce the pressure on a lumbar spinal nerve root that is impinged on by an obstructed foramen -​ Extension increases natural lordosis -​ Extension between L3 and L4 example: inferior articular facet of L3 slides inferiorly and slightly posteriorly relative to the superior facets of L4 -​ Mckenzie exercises use lumbar extension to reduce centralization of pain radiating to the lower back, helps with posterior herniated nucleus pulposus pain but this is not good for someone with a fully herniated disc at L5/S1 level because you don’t want to compress the S1 nerve further by reducing vertebral canal with extension -​ There is an anterior pelvis tilt with lumbar extension along with anterior shift of the nucleus pulposus (uses lumbar extensors and hip flexors) and a posterior pelvic tilt with lumbar flexion along with posterior shift of the nucleus pulposus (uses hip extensors and abdominal muscles) The Trunk The abdominal muscles support viscera/thoracic cage, aid in ventilation, coughing, etc., aid in posture, protect internal organs, produce gross trunk and pelvic motions, aid in voiding and other activities that require valsalva Abdominals: -​ Rectus Sheaths: blending of external obliques, internal obliques, transverse abdominus, and rectus abdominus into anterior and posterior connective tissue sheets -​ Linea Alba: the blending og these sheaths at midline from xiphoid to pubis, divides rectus abdominus into Right and Left halves, aids in force transfer from R to L, strengthens abdonimal wall, diastasis recti (a condition where the muscles of the front belly separate) common after pregnancy and is measured by fingers, how fat apart the halves are. Only fix is surgical repair -​ Tendinous Insertion: three fibrous bands of rectus abdominus to make the six pack look to prevent bowstringing of the muscle Thorax/Trunk Posterior Wall -​ Psoas Major: originates off lumbar spine, produces lordosis and stabillizes, attaches to femur and flexes the hip -​ Psoas Minor: comes off lumbar vertebrae (some people do not have a psoas minor) -​ Quadratus Lumborum: best exercise is sideplanking -​ Iliacus: originates off the pelvis, attaches to femur and flexes hip -​ Transverseus Abdominis -​ E/I Obliques -​ Functional Associations -​ Core stability: stable trunk and pelvis despite destabilizing forces, correct posture and support, force production and transfer (TL Fasciae), injury and pathology reduction up and down the chain The Core: runs through the length of the trunk and pelvis to stabilize the spine, pelvis, and shoulder girdle to create a solid PROXIMAL base of support via coactivation and timing, balance, endurance. Proximal stability for frontolled distal mobility. Powerful movements are generated at the trunk to transfer momentum proximal to distal. -​ Rectus abdominus: Not a rotator the primary motion is flexion and regulating pressure (coughing, breathing) -​ Int obliques: rotate ipsilaterally with contraction (also help with flexion and sidebending) -​ Exterior obliques: rotate contralaterally with contraction (also help with flexion and sidebending) -​ Transverse abdominus: deep, main function is to stabilize and regulate pressure, origin of TLF -​ Erector spinae -​ Deep paraspinals -​ Quadratus lumborum: sidebending and attaches to lower rib for rib stabilization, helps with spinal stabilization, hip/pelvic hiker in open chain and a trunk sidebender in close chain -​ Glutes -​ Hamstrings -​ Psoas minor and major -​ Iliacus -​ Rectus femoris -​ Hip adductors -​ Diaphragm -​ Pelvic floor muscles -​ Lats and shoulder girdle -​ TL fasciae A weak and unbalanced core is highly correlated to back injuries. -​ Imbalance, timing, control, endurance -​ The client may be very strong if you MMT or functionally test but they are often unbalanced and have poor endurance of these muscles -​ Transverse abdominis is the first muscle to activate prior to ALL movement UE and LE. -​ Pts with low back pain are shown to have 3x decreased transverse abdominis activation -​ TrA arises from which structure????? -​ Internal oblique and multifidus also very important early activators, pts with LBP also have multifidus atrophy -​ READ NEUMANN 427-430 TrA: -​ Limited ability to generate trunk motion -​ Major action: increase fascial tension, compress SI/SymPub; Modulation of IAP for lumbopelvic stability (drawing in) -​ Major factor in L5-S1 stabilization -​ How will you instruct pts to engage the TrA: bring belly button towards the spine or nuts to guts  -​ Unless accompanied by activation/coordination of diaphragm and pelvic floor muscles, contraction will just displace abdominal contents Partnership -​ TrA is closely linked to the diaphragm and the pelvic floor muscles -​ In combination with the multifidus, these muscles create a lumbopelvic corset that stabilize pelvic joints and the lumbar spine during dynamic and static tasks Diaphragm -​ Origin from L1-L3 (some say to L5) -​ Forms a central tendon -​ Innervated by phrenic nerve C3, 4, 5 -​ Separates thoracic and abdominal cavities -​ Pericardium rests centrally, L and R domes; R a little higher -​ With exhalation, domes will rise to approx. 5th rib Lifting -​ Lifting is a leading cause of back and shoulder injuries and account for more than 35% of all missed time from work -​ Four stages to consider: preparation, lifting, carrying, setting down -​ Discuss the importance of the BOS during lifting (size, shape, direction) -​ How does the LOG affect lifting -​ Discuss concept of IMA vs EMA for stability you want them to be equal -​ To make IMA and EMA as equal as possible you want to SHORTEN EXTERNAL MOMENT ARM (bring arms in if carrying something) -​ How does position of the item affect lifting -​ What about valsalva: increases pressure and increases spinal stability, really only bad for older people with blood pressure or heart problems. -​ What is the role of the TL fasciae: stabilizes spine through contraction of glut max, TA, latissimus dorsi SPECIAL FIGURE 10.7 AND TABLE 10.7 and PAGES 419-426 SPECIAL FIGURE 10.7: Two contrasting Lifting Techniques: The Stoop versus the Squat Lift Stoop lift: extending the hips and lumbar region while the knees remain slightly flexed. This is associated with greater flexion of the low back. The greater external torque requires greater extension forces from the low back and trunk extensor muscles. In combination with a markedly flexed lumbar spine, the stoop lift can create large and possible damading shear forces on discs. The squat lift is better for lower back but harder on the knees. Sqaut lift also requires greater work done by the body Dr Ryan’s Lecture: Abdominal Wall and Inguinal Region -​ Quadrants are divided by line through umbilicus at L3-L4 -​ Other planes are transpyloric plane (L1), Subcostal plane (L3), Transtubercular plane (L5), Midclavicular plane (through midpoint of clavicles) These split the abdomen into 9 divisions  -​ -​ Central tendon of diaphragm is where diaphragm inserts (it inserts on itself) -​ The diaphragm forms 3 tendinous arches (aorta is under the middle median arcuate ligament) -​ Diaphragmatic Openings: caval hiatus: inferior vena cava, Esophageal hiatus: esophagus and right/left gastric nn. Aortis hiatus: abdominal aorta, azygos v., thoracic duct, greater splanchnic n. Beneath median arcuate ligament Anterior Abdominal Wall -​ Layers aer skin, superficial fascia (campers and scarpas: unique to abdominal area), deep fascia, muscle, transversalis fascia, extraperitoneal fat, parietal peritoneum (this is a serous membrane like pleura of lungs) -​ Scarpa’s Fascia is continuous with superficial penile/slitoral fascia then Dartos fascia (only in men on ballsack), Colles fascia (perineum) -​ Linea alba: line in the middle, a lof of muscles insert here -​ Linea semilunares: white band on side of rectus -​ 3 intertendinous connections -​ Arcuate line: where rectus sheath becomes very thin posteriorly (about an inch below the belly button) The Inguinal Ligament  -​ Lower free edge of the external oblique aponeurosis forms the inguinal ligament -​ This ligament spans from the ASIS to the pubic tubercle -​ Acts as a transition zone at which the external iliac av. transitions into the femoral av. The Conjoint Tendon -​ The distal and medial aponeuroses of transversus abdominis and internal oblique fuse together to form conjoint tendon -​ Attaches to pubic crest and blends with anterior rectus sheath -​ Supports the integrity of the anterior abdominal wall and inguinal canal Median umbilical fold/ligament: remnant of urachus from when in the womb Inferior epigastric vessels are the same things as the lateral umbilical folds Arteries: Superior epigastric and inferior epigastric Nerves: Iliohypogastric and ilioinguinal The Pelvic Girdle -important for BOS and posture - transmits forces between upper body and lower extremities through CONTRALATERAL Lower extremities -Throw with right arm, force passes through sacrum to left leg Gross Movements: -​ Anterior pelvic tilt: sagittal plane -​ Posterior pelvic tilt: sagittal -​ Lateral pelvic tilt (obliquity): frontal plane (raise right leg, that is a left pelvic tilt. Right QL is working) -​ Pelvic Rotation: anterior, posterior “retraction”, occurs simultaneously: transverse plane Pelvic Force Couple -​ Anterior tilt: erector spine goes up, iliacus and psoas major goes down, rectus femoris goes down, sartorius goes down and pelvis tilts anteriorly -​ Posterior tilt: rectus abdominis goes up, external oblique goes up and into the body (toward the back), gluteus maximus goes down and into the body (toward the front), hamstring (semitendinosus, semimembranosus, biceps femoris) goes down, pelvis tilts posteriorly, also a taut iliofemoral ligament Effects in Different Planes of Pelvis on Femoral Hip Rotation with stable trunk 1.​ Sagittal Plane -​ Anterior tilt causes slack iliofemoral ligament and flexed biceps femoris -​ Posterior tilt causes tight iliofemoral ligament and flexed rectus femoris 2.​ Frontal Plane -​ Whatever side is drooping has an intertransverse ligament stretched, adductor brevis and abductor longus, pubofemoral ligament (abduction picture) ABDUCTION of hip is leg you’re standing on. You can also stand on one leg and let the hanging leg drop and you get adduction on standing leg and abduction on dropped leg -​ Whatever side is hiked has piriformis, tensor fasciae latae and iliotibial band, (adduction picture) ADDUCTION of hip is leg you’re hiking -​ Named by what side is down (left pelvic tilt has left side down and right leg hiked) 3.​ Transverse Plane -​ Internal rotation: one foot is stationary and pelvis moves FORWARD with other foot, spine rotates backward (hands out, whatever foot is IN the hand when you rotate is the foot that is internally rotated) -​ External rotation: foot stationary and pelvis moves BACKWARD and spine rotates forward Effect of Pelvic Tilt and Hip/Knee Angle on Lower Body Posture -​ Lordotic Back: anterior pelvic tilt, slightly flexed hips, hyperextended knees, forward tilt of pelvis pulls lumbar spine into hyper-lordosis ONLY ONE THAT HAS HIP FLEXION -​ Flat Back: posterior pelvic tilt, slightly hyperextended hip and knee joints, pelvic tilt posteriorly pulls lumbar spine flat -​ Swayback: forward shifted pelvis, posterior tilt, hyperextended hip and knee joints, upper trunk shifts backward to compensate (caused by weak glute muscles) -​ Balanced Posture: neutral pelvic tilt, neutral angle of hip and knee joints Normal lumbar and hip flexion?: can touch toes like normal Limited hip flexion with excessive lumbar flexion: look like a humpback and cannot reach toes at all, body is shaped like a candy cane Limited lumbar flexion and excessive hip flexion: look like a table with back completely flat and hips are at 90 degree angle (body is shaped like an upside-down L Lumbopelvic Rhythm During TRunk Extension Early Phase: -​ Lumbar extensors are pulling down, gluteus maximus pulls down and in, hamstrings pull down Body weight is through center of mass Sacroiliac Joints -​ Could be linked to SC joints -​ S1-S3 -​ “Keystone” -​ Attaches to pelvis at auricular surface  -​ Stabillized by gluteus maximus -​ Sacroiliac joint allows rotation of the pelvis over the femoral head to change the configuration of the lumbar spine, this is known as LUMBOPELVIC RHYTHYM -​ Functions are for stress relief along with stability within the pelvic girdle -​ Transfer of forces between axial skeleton and lower extremities, force taken through one leg and dispersed on the contralateral tunk -​ SI joints move but not a lot and you can’t really see/measure CANNOT measure -​ Lat dorsi and glut max make an X formation to provide ascending and descending forces -​ Starts out as synovial in youth and then changes to amphiarthrodal between puberty and young adulthood -​ WB joint but we only worry about it in single leg stance or when we create force above -​ May eventually ossify -​ Sacral side is hyaline, iliac side is fibrous (so part synovial and part fibrous) -​ Auricular surfaces are synovial, and tuberosities are fibrous -​ Bottom ⅓ of joint is synovial -​ Very variable from person to person and even within a person -​ Large diarthrodial joint -​ Only the anterior third of the interface between the sacrum and ilium is a true synovial joint, the rest of the junction is comprised of an intricate set of ligamentous connections -​ Very thick and strong capsule with thickened INFERIOR portion -​ POSTERIOR region is THINNEST and weakest, might even be absent -​ Can be injured by falling on it directly, or by stepping into a hole unexpectedly -​ Trauma to this region can also be from childbirth, which is called PELVIC GIRDLE PAIN SYNDROME -​ Repetitive torsion can cause injury suhca s in figure skaing or sports with frequent kicking or high velocity throwing. -​ Can be injured with bad posture -​ Leg length asymmetry of only 1 cm would cause a 5 fold increase in compression load across the SI joint on the longer limb side -​ Pelvic Ring: SI joints, sacrum, ilium, pubis, ischium, pubic symphysis joint. The pelvic ring transfers body weight bidirectionally between trunk and femurs. Sacrum is keystone of pelvic ring -​ POSTERIOR layer of TLF attaches to spinous processes of all lumbar vertebrae and the sacrum and the iliam near posterior superior iliac spines. These attachments provide mechanical stability to the SI joint Clinical Connection 12.2 Restirctions in the extensibility of the piriformis muscle may limit hip internal rotation, compress the sciatic nerve or produce abnormal stress on the sacroiliac joint. Can also create a trigger point in butt that radiates down the leg. This is piriformis syndrome. A way to treat this is to STRETCH the piriformis by doing FULL FLEXION and EXTERNAL ROTATION of the hip, with knee FLEXED. Seems weird to stretch piriformis with external rotation because that is its action but with hip flexed, the muscle switches from external rotsator to internal rotator.  Overall: ATYPICAL DIARTHROSIS​ - synovial membrane and fluid - joint capsule - articular cartilage - ligaments - fibrocartilage (not normal in typical joint) - discontinuity of capsule (not normal in typical joint) - rough and ridged atricular surfaces (not normal in typical joint) Lumbrosacral Ligaments Iliolumbar ligaments -​ Two bands (A and P) from tips of L5 TP to B posterior iliac crests -​ Some also have a weaker band at L4 -​ Not present at birth, begins as metaplasia of fibers from QL -​ Fully developed by 3rd or 4th decade -​ Degenerates after 4th-5th decade -​ Extrememly strong to stabilize L4-L5 on S1, resists all motions -​ Protects disc from excessive torque Ligaments of the SIJ Anterior Sacral: thinnest ligament, can be injured or stressed with DISTRACTION/COMPRESSION testing Your pt has chronic low back pain and atrophy of multifidi, what ligament is most likely also weakened? POSTERIOR SACROILIAC because it blends in with multifidi Iliolumbar Ligament: stabilizer for lumbosacral joint blends with parts of anterior sacroiliac ligament. Reinforces ANTERIOR SIDE OF JOINT Anterior Sacroiliac Ligament: thickening of the anterior and inferior regions of the capsule REINFORCES ANTERIOR SIDE OF JOINT, thinnest ligament, can be injured and stressed with DISTRACTION/COMPRESSION testing Posterior Sacroiliac Ligament: palpable inf. To PSIS and connect PSIS to S3-4, fibers multidirectional -​ Blends with sacrotuberous ligament, ES, multifidus, and TLF Interosseous Sacroiliac Ligament: short, deep within posterior sacroiliac and forms major connection, resists ANT/INF motion. Strongest ligament of sacroiliac joint Sacrotuberous Ligament: 3 fibrous bands, resists POST/SUP motion and anterior tilt (NUTATION). Hamstrings are anatomically connected Sacrospinous Ligament: deep to and blends with sacrotuberous ligament, resists anterior tilt (nutation) Form Closure: Stability of the pelvic ring provided by anatomy of the ring itself -​ Bony articulations/capsule -​ friction/grooves of atricular cartilage -​ Ligaments -​ Shape of the joints -​ Ridges -​ keystone  Force Closure: Addition of intrinsic and extrinsic forces to aid in stability (more passive) -​ Muscles -​ Gravity -​ TLF The SI joint is supported by a network of muscles that help to deliver regional muscular forces to the pelvic bones. The gluteus maximus, piriformis, and biceps femoris are functionally connected ot SI joint ligaments, so their actions affect joint mobility Major Muscles of Force CLOSURE -​ G max, biceps femoris, ES, Lats, TA -​ Muscles that play a role in FFwd Activation: TA, Internal Oblique, Multifidus, Piriformis (can spasm/shortened and can pull sacrum one way or another ot have a torsion), and pelvic floor muscles -​ Tension in TLF aids -​ Muscles contract and cause tension in TLF -​ Force of gravity SIJ FORCE CLOSURE: -​ stability/increased stiffness caused through isolated contractic of muscles -​ 35 muscles attach to pelvis and sacrum and help stabilize -​ Major muscles of force closure: Gmax, Biceps femoris, ES, Lats, TrA -​ Muscles that play a role in Feed forward Activation: TA, Internal Oblique, Multifidus, Piriformis, and pelvic floor muscles -​ Tension in TLF aids -​ -TA contracts first SIJ Kinematics -​ Base (wide part at top) vs apex (pointy at the bottom) -​ Movement of SACRUM: -​ Rotation: nutation/counter-nutation, 2-3 degrees actively and up to 7-8 degrees passively -​ Nutation: when the base (top) moves anteriorly -​ Counter-nutation: when you nutated and then go back to neutral -​ Translation: 2-3 mm  -​ Increased motion in young females -​ Kinematically linked with symphysis pubis and lumbar spine (spine extends, sacrum nutates) -​ Functionally linked with hip joint Sacral motion-Closed kinematic chain: lumbar extension increased lordosis, sacral nutation Pelvic Motion secondary to hip motion: lumbar flexion decreased lordosis, sacral extension, pelvic posterior tilt SIJ (1-3) -​ Potential source of LB, buttock, and LE pain -​ Has nociceptors -​ Not a common diagnoses -​ Test clusters: take minimum of SIX special tests that target SI joint with majority of them being positive before you can say SI joint is involved (can’t do an arthrogram) -​ 10-25% of pts with persistent mechanical (unilateral) pain below L5 have SI joint dysfunction -​ Every lumbar dermatome crosses near/over this area -​ Posterior sacrococcygeal plexus/lateral neurovascular branches of the dorsal sacral rami -​ Joint inn. L2-S2? -​ Ligaments inn. by dorsal rami S1-S4 -​ Piriformis, quadratus lumborum can refer to SIJ -​ Common complaints: sharp pain with SLS, pain with forward flexion, rising from sitting, getting in/out of car, clicking, clunking feeling. May report fall onto butt or over one sided loading or trauma (foot on brake, horseback riding, SLL, etc.) -​ Common mechanism involves bending forward and twisting trunk to reach either right or left side SIJ Kinematics -​ Innominate motion on sacrum: slight anterior and posterior motion with normal gait=stress relief (step forward with right, right innominate rotates back posteirorly and left innominate rotates forward slightly) -​ Abnormal: torsions (innominate stuck rotated due to ridges on the joint can be anterior or posterior) only one that is actually legit and studied, rotations, upslips (one innominate higher than the other), inflares (one side either flares out or in on the pelvis), outflares THE HIP: OSTEOLOGY, ARTHTROLOGY, MUSULATURE, AND FUNCTION Functions of the hip: accept WB forces, transfer and balance of forces, provide a fulcrum for lower extremity motion, provide a fulcrum for pelvic and spinal motion, contribute to body progression Motions at the hip: flexion (bringing leg forward)/ extension, abduction/adduction, ER (toes turning out)/IR, Circumduction (combination of all motions) Force Couple: force couples at hip/pelvis actively produce lumbar compensations (hip extension and posterior pelvic tilt, upward pull of rectus=flattening of lordosis) (hip flexion and anterior pelvic tilt, downward pull of ilipsosi=increases lordosis)  Open Kinetic Chain movement: femur on pelvis Closed kinetic chain movement: pelvis on femur or pelvis/trunk on femur Anterior pelvic tilt= hip flexion, trunk flexion Posterior pelvic tilt= hip extension, trunk extension Lateral pelvic tilt= adduction or abduction at hip joint Pelvic rotation= either IR or ER (remember IN the lines, IR) Hip Joint: Structure -​ Ball and socket -​ True synovial joint: diarthrosis, hyaline cartilage, synovial membrane, synovial fluid, joint capsule, associated ligaments -​ Focus is in closed chain -​ Kinematically linked to pelvis, lumbar, spine, and KNEE Femoral head: ⅔ of a sphere covered in hyaline cartilage Fovea, depression in the center of the head: ligament of femoral head called ligamentum teres Femoral Neck: ~5 cm LONG MOMENT ARM The angle of the femoral head and femoral neck relative to femoral shaft is called angle of inclination Normal is 125 degrees, coxa valga is 140, compensation with ABDUCTION of femur and VARA of knee (bowlegged) coxa vara is 105, compensation with ADDUCTION of femur and VALGA knee (to line up the centers of head and acetabulum) predisposed to patella lateral displacement The angle of inclination is good for stability, and angles down into base of support Coxa valga or vara causes compensation with hip and knee position (bad) You want the cener of the femur and the center of the acetabulum to line up perfectly (this is normal 125 degree) Coxa Vara: 95 degrees  -​ length/MA: shorter leg structurally -​ Forces: the force is directed into center of acetabulum so not as prone to arthritis -​ Stability: more stable than valga because its more in the socket -​ MA/line of pull for GMed: has larger angle of insertion so is better for rotational forces, abduction -​ Injuries: higher liklihood of patella femoral issues, femoral neck fracture more common because of longer moment arm -​ PF Joint: s Coxa Valga: -​ length/MA: longer leg structurally -​ Forces: the force of valga leg will be directed more superiorly -​ Stability: less stable that vara -​ MA/line of pull for GMed: has a smaller angle of insertion, glut med is not very good at abduction. WEAK glut med, higher likliehood of compression forces -​ Injuries: arthritis in superior acetabulum, higher likelihood of TRENDELENBURG, fracture of femoral head -​ Children: valga likely in children, born with slight valga and should decrease with gravity Angle of Torsion: angle between head/neck of femur and shaft of femur 15 degrees is normal, slightly rotated forward (called anteversion) Excessive anteversion (more than 15): compensate with INTERNAL ROTATION, causes pigeon toed, W sitting causes this Retroversion (less than 15 degrees), head and neck of the femur are rotated posteriorly, compensate with EXTERNAL ROTATION, frog-eyed patellas and duck footed Kids with Cerebral Palsy: have coxa vara, valga at the knee, toes pointed in, anteverstion Acetabulum: socket that the femoral head inserts into -​ Juncture of 3 bones, 80% ilium and inshium, also has pubic bone -​ Doesnt Completely ossify until after age of 15 -​ Central portion non-articular (doesnt meet with femoral head): fat pad and synovium -​ Pincer deformity occurs here -​ Angle of Wiberg (center edge angle): amount of inferior tilt of acetabulum, 35-38 degrees, smaller angle=decreased SUPERIOR stability -​ Labrum: wedge-shaped fibrocartilage “horseshoe”, adds stability, adds concavity, deepens socket, force dispersion, friction reduction -​ Transverse acetabular ligament: spans gap at inferior portion, forms “roof”, allows a tunnel for arteries in leg -​ The Capsule: very thick and strong, thickest ANTERIOSUPERIORLY and thinnest POSTERIOINFERIORLY, surrounds entire joint, entire rim of acetabulum, blends with labrum, covers femoral neck and has 2 layers of fibers: superficial/longitudinal and deeper/curcular The deeper/circular ones form a collar around femoral neck called zona orbicularis  Ligaments of the Hip Iliofemoral (Y) Ligament: -​ Anterior -​ Restricts EXT and ER/IR, ABD/ADD -​ Has fibers running in various directions and twists like a coil ​ Pubofemoral Ligament: -​ Medial -​ Restricts EXT, ABD, ER Ischiofemoral Ligament: -​ Posterior -​ Restricts EXT, IR, and ADD -​ Some fibers blend with zona orbicularis There is not a lot of restriction on flexion at the hip All ligaments are coiled or twisted in somewhat neutral=stable joint Extension increases twists but joint articulation is LESSENED Flexion, ABD, and ER loosed twist but joint articulation is GREATER Flexion and ADD loosens twists and joint articulation is LESSENED So…flexion and adduction is not a stable position for the joint, position that often results in dislocation Adding IR also makes it unstable. This is where hip precautions come from and how surgeons move hip out of socket for hip replacements Open Packed (two articulating surfaces have a nice distance where ligaments are slack) joint mobilization position, : flexed, ER, ABD Closed Packed (articulating surfaces are close together, ligaments are tight): EXT, IR, ADD -​ Extremely important for joint nutrition, going from closed packed to open acts as a pump for nutrition Muscles of the Hip Joint -​ Position and fiber alignment clue you into actions ANTERIOR: -​ Iliacus: primary mover at hip joint -​ Psoas major/minor: -​ Rectus femoris: only quad that crosses hip joint -​ Sartorius: crosses hip and knee, longest muscle, inserts in Pes Anserine on medial tibia POSTERIOR -​ Gluteus maximus: main extensor and external rotator  -​ Piriformis: sciatic nerve exits underneath (most of the time) so if piriformis becomes spastic, short, hypertonic, etc. it can compress onto sciatic nerve called Piriformis Syndrome, very variable though there are 7 different possible positions when we flex the hip joint, the line of pull between the sacrum and the greater trochanter changes so in anatomical position you internally rotate to stretch but when you flex past 90 it stretches with external rottation -​ Gemellae superior: ER -​ Gemellar inferior: ER -​ Obturator internus -​ Obturator externus -​ Quadratus femoris -​ Hamstrong group (SM, ST: inserts into pes anerine, BF (LH)) Short head of hamstring does not work at hip, only knee flexion For hamstrings: may perform slight tibial rotation-take into account for MMT isolated MEDIAL -​ Adductor longus -​ Adductor brevis -​ Adductor magnus -​ Gracilis: crosses hip and knee -​ Pectineus LATERAL -​ Gluteus Medius: DELTOID OF THE HIP, can do every motion at the hip or assist with every motion EXCEPT ADDUCTION, blends into iliotibial band -​ Gluteus Minimus: assists with ABD and stabilizes pelvis -​ Tensor Fascia Latae (ITB), also helps with flexion, and can help at knee joint, inserts on gerdy’s tubercle Hip Joint Bursa: -​ Variable numbers -​ Two main: over greater trochanter, under common tendon of Psoas major and Iliacus (ischail bursa) -​ Function: absorb compression forces, reduce friction, add cushioning Trendelenburg: Right trendelenberg: right weak glut med, left side drops (eccentric), can’t control=think eccentric If the hip drops with trendelenberg is UNCOMPENSATED​ Compensated menas you sway toward the weak side (not dropped side) and you shorten the moment arm ITB/Snapping Hip/COxa saltans External snapping hip syndrome: Internal snapping hip syndrome: iliopsoas tendon catches on femoral head or iliopectineal eminence duing hip flexion Femoroacetabular Impingement: -bony deformity of either head and neck of femur, or acetabulum, or both Cam: abnormalities at femoral head-neck junction causing cartilage/labral wear on acetabulum (due to overgrowth) Pincer: overcovreage of acetabulum on normal head/neck, pinching on rim Mixed: most common Impingement for all is usually on ANTERIOR SUPERIOR portion Acetabular Labral Tears: often traumatic, but also degenerative associated with FAI, excessive anteversion Signs: clicking, instability, weight bearing problems Needs surgery, but cant actually fix labrum tear LUMBAR AND SACRAL PLEXUS Lumbar Plexus: -​ Anterior primary rami of the spinal nerves become arranged in complicated patterns or plexuses -​ Originates from L1-L4 (some combination from T12, subcostal) -​ Afferent and efferent supply to anterior and medial LE as well as pelvis and abdominal wall -​ In lumbar region within Psoas Major  -​ Contributes to formation of peripheral nerves Peripheral Nerves Of Lumbar Plexus -​ Iliohypogastric: T12-L1 - emerges lateral to psoas, passes laterally and divides into the lateral branch (skin proximal to lateral thigh), anterior branch (skin of symphysis pubis) - clinical relevance is athletic pubalgia (sports groin) strain of the insertion of rectus abdominus and insertion of adductors of leg, common in someone who extends the leg backwards like to kick a soccer ball, form of tension injury to the nerve - hernia and pregnancy can also cause stretch of this nerve -​ Ilioinguinal: T12-L1 - runs inferior to iliogypogastric (may join) - pierces Internal Oblique, upper medial thigh and portions of genitals - Clinical Relevance: iliac crest harvesting (can get nicked or compression, etc.), femoral catheter - Symptoms: maybe hypo-, hyper-aesthessi (increased or decreased sensation), pain in groin, genitals, inner thigh. Pain will increase with HIP EXTENSION - Genitofemoral ​ - L1-L2 ​ - runs through psoas, divides anteriorly into genital and femoral branches ​ - Genital: some regions of genitals, cremaster muscle ​ - femoral: skin proximal medial though, femoral artery ​ - Clinical Relevance: hernia, C-section, pregnancy—-> groin pain ​ Pain will increase with ER/IR, walking if this nerve is damaged -​ Lateral Femoral Cutaneous: L2-L3, PURE SENSORY - runs laterally across iliacus and ends up crossing beneath inguinal ligament near ASIS - CR: inguinal ligament entrapments, seatbelts, obesity, pregnancy, uterine fibroids, diabetes, ITB (tight iliotibial band). Often hyperalgeia to touch (Increased sensation, feels prickly). Walking down stairs, prolonged anterior tilt, and extension at hip and knee make pain worse -​ Femoral: L2-L4 - arises from lateral border of psoas above inguinal ligament, runs inferiorly to femoral triangle, lateral to artery - above inguinal ligament, supplies iliacus, psoas major - below, supplies quadriceps femoris, sartorius, pectineus - sensory to anterior medial thigh via anterior femoral cutaneous branch, knee via saphenous branch - Clinical relevance: rare, but diabetic neuropathy is most common, trauma (stretching?). Total hip arthroplasty, pelvic fractures or tumors - Causes inguinal pain, paraesthesia to anterior thigh, “knee buckles”, Hyporeflexia at patellar tendon (L4) -​ Obturator: L2-L4 - runs along medial aspect of psoas major, down side wall of pelvis and leaves through obturator foramen - divides into anterior and posterior divisions - motor to adductors - sensory to small part of proximal medial thigh - Clinical Relevance: isolated injury is rare, ovaries Peripheral Nerve Field is NOT the same as a Dermatome Dermatome: area of skin supplied by ONE nerve root Peripheral nerve field: combined nerve roots to show a certain peripheral nerve field for a nerve (ex: femoral nerve) PNF: (know the ones down to the knee, both anterior and posterior) Dermatome: LUMBROSACRAL TRUNK AND SACRAL PLEXUS:​ - LS Trunk: anterior rami of L4 and L5 that contribute to sacral plexus. Connects lumbar plexus to sacral plexus Peripheral Nerves of Lumbosacral Trunk and Sacral Plexus -​ Superior Gluteal: L4-S1  - Exits via greater sciatic foramen, enters gluteal region above piriformis - motor to glute min, glute med, and tensor fascia lactate - no sensory -​ Inferior Gluteal: L5-S2 - Exits via greater sciatic foramen, enters gluteal region below piriformis - motor to glute max - no sensory -​ Sciatic: L4-S3 - exits via anterior sciatic foramen, inferiorly to piriformis - 2cm - divides tibial and common peroneal (fibular) neat posterior knee usually but ~ 10% divide up near pelvis - runs across deep ER, then runs under LH biceps femoris - motor to: posterior thigh - no direct cutaneous branches off sciatic - Clinical relevance: trauma, hip flexion contracture/anterior tilt, facilitated piriformis, hamstring issues, careful when dry needling because you dont want to hit it when doing dry needling on the piriformis Sacral Plexus Peripheral Nerves -​ Posterior Femoral Cutaneous: S1-S3 - also exits via anterior sciatic foramen, inferiorly to piriformis - Has 3 branches: cutaneous, inferior cluneal, perineal - sensory to skin of posterior thigh and leg, also innervates skin of perineum - Clinical Relevance: near isch, proximal hamstring tears, bicyclists, trauma, horseback riders, pain with sitting -​ Pudendal: S2-S4 - main innervation of perineum - motor to muscles of pelvic floor and perineum - sensory to perineum, genitalia - Clinical relevance: “saddle area”, childbirth, bicyclists, DM, MS - compression between sacrotuberous and sacrospinous ligaments - compression in Alcock’s canal: urinary hesitancy, frequency, urgency, altered perineal/genital sensation, pain, impotence