Posture 2024 PDF

POSTURE By: Rene John D. Belarso, PTRP Posture  Position or attitude of the body, relative arrangement of body parts for a specific activity, or a characteristic manner of bearing one’s body; either in sitting, upright or recumbent Posture  Described by t...

POSTURE By: Rene John D. Belarso, PTRP Posture  Position or attitude of the body, relative arrangement of body parts for a specific activity, or a characteristic manner of bearing one’s body; either in sitting, upright or recumbent Posture  Described by the positions of the joints and body segments and also in terms of balance between the muscles crossing the joints. Base of Support (BoS)  Defined by an area bounded posteriorly by the tips of the heels and anteriorly by a line joining the tips of the toes, is considerably smaller than the quadrupedal BoS Center of Gravity (CoG)  The point where the mass of the body is centered and is referred to as the center of mass (CoM) Curves of the Spine  Lordosis  Kyphosis The curves & flexibility of spinal column are important in withstanding the effects of gravity and external forces Static and Dynamic Posture Static Posture  The body & its segments are aligned & maintained in certain positions; standing, lying or sitting Dynamic Posture  Refers to postures in which the body &/or segments are moving; walking, running etc. Postural Control  Can either be static or dynamic  Refers to the person’s ability to maintain stability of the body or body segments in response to forces that threaten the body’s structural equilibrium Major Goals and Basic Elements of Postural Control  Absent or Altered Inputs and Outputs  Muscle Synergies (Sensory & mechanical Perturbations) Postural Control Static Postural Control  Involves maintenance of a particular posture against gravity Dynamic Postural Control  Involves maintenance of stability during movements of the body/segments, &/or changes in the supporting surface. Postural Control  Maintenance/control of posture depends on the integrity of the CNS, visual system, vestibular system, musculoskeletal system and inputs from receptors in & around the joints, tendons & ligaments Internal & External Forces Internal Forces  Muscle activity, passive tension of ligaments, tendons, capsules & other soft tissue structures External Forces  Inertia, gravity and ground reaction forces (GRF) Line of Gravity (LOG)  plumbline  ant; post; lat  Combined action line formed by the GRFV & gravity line Line of Gravity (LOG) Joints LOG Gravitational Passive Active Moment Opposing Opposing Forces Forces A-O Joint Anterior Flexion Lligamentum Posterior Nuchae Neck Muscles Tectorial membrane Cervical Posterior Extension ALL Thoracic Anterior Flexion PLL Extensors Ligamentum Flavum Supraspinous ligaments Line of Gravity (LOG) Joints LOG Gravitational Passive Active Moments Opposing Opposing Forces Forces Lumbar Posterior Extension ALL SI Joint Anterior Flexion type Sacrotuberous motion Lig. (nutation) Sacrospinous Lig. Sacroiliac Lig. Hip Joint Posterior Extension Iliofemoral Iliopsoas Ligament Knee Joint Anterior Extension Posterior Joint Capsules Ankle Joint Anterior DF Soleus POSTURAL ANALYSIS Reduction of energy expenditures & stress on the supporting structures is the goal of any postures Optimal Posture Ideal Posture  The body segments are aligned vertically and the LOG passes through joint axes  LOG falls close to, but not through, most joint axes  Compression forces are distributed optimally over the weight-bearing surfaces of the joints  No excessive tension on the ligaments & muscles Lateral View Optimal Alignment Ankle & Knee Ankle-midway between DF & PF Knee is in full extension LOG falls slightly to lateral malleolus; Anterior to the midline of the knee, posterior to patella Hip & Pelvis Hip-neutral position; Pelvis-no APT or PPT ASIS & Symph. Pubis-Vertical line; ASIS & PSIS- horizontal line LOG passes slightly posterior to axis of hip joint, through greater trochanter SI & LS Joints Optimal LS angle of 30 deg LOG passes slightly anterior to SI joint; Through the L5 body & close to axis of rotation of LS joint Lateral View Optimal Alignment Vertebral Column LOG passes posterior to axis of rotation of cervical & lumbar & anterior to thoracic & through the body of L5 Maximal gravitational torque occurs at the apex of each curve – C5,T8 & L3 (farthest from the LOG) Head Passes through the external auditory meatus, posterior to the coronal suture & through the odontoid process Lateral View – Deviations from Optimal Alignment Flexed Knee Posture  LOG falls posterior to the knee joint  Between 15-30 deg flexion – rapid rise in tension of quads → increase in compressive forces on tibiofemoral & patellofemoral joints  Related to ankle & hip Hyperextended Knee Posture (Genu Recurvatum)  The LoG is located considerably anterior to the knee joint axis - causes an increase in the external extensor moment acting at the knee, which tends to increase the extent of hyperextension  Puts the posterior joint capsule under considerable tension stress. Lateral View – Deviations from Optimal Alignment Excessive Anterior Pelvic Tilt  Forces the lumbar vertebra anteriorly (lumbar lordosis)  Results in compenatory: ◦ Thoracic kyphosis ◦ Forward head  IV discs –anterior tension & posterior compression A/P View  Bisects the body into two symmetrical halves  Joint axes of the hip, knee, and ankle are equidistant from the LOG  Gravitational line transects the central portion of the vertebral bodies A/P View - Deviations from Optimal Alignment Knees  Genu Valgum ◦ Tensile/distraction stress on medial knee structures and compressive stresses on lateral knee joint structures ◦ Atrophic changes on medial meniscus and hypertrophic changes lateral meniscus ◦ Causes pronation on foot with accompanying stress in medial longitudinal arch & abnormal WB on postero-medial aspect of calcaneus Genu Valgum & Varum A/P View - Deviations from Optimal Alignment Foot & Toes  Pes planus/flat foot ◦ Displacement of navicular (feiss line) & stretching of plantar cancaneonavicular/spring lig ◦ Rigid – structural deformity & maybe hereditary; arch is absent in non-WB & toe standing ◦ Flexible A/P View - Deviations from Optimal Alignment Foot & Toes  Pes Cavus  Hallux Valgus  Claw Toes – hyperextension of MTP with flexion of PIP & DIP; associated with pes cavus  Hammer Toe – hyperextension of MTP & DIP & flexion of PIP Anterior View (Assesment)  head  Shoulder  clavicles/acromioclavicular jt  waist angle  carrying angle  iliac crest/ASIS  patellae  knees  arches of the foot  out-toeing (fick’s angle 5-18) Posterior View  Head  knee jt level  Shoulder  heels (varus/valgus)  scapula  spine  ribs protrusion  waist angle  arms from body  PSIS  Gluteal folds Scoliosis  Lateral curvature of the spine  Maybe: ◦ Non-structural – deformity is not fixed and outside the spine ◦ Structural – deformity is associated with vertebral rotation; cannot be completely corrected or maitained Etiology A. Structural Scoliosis 1. Idiopathic Scoliosis 1. Infantile 2. Juvenile 3. Adolescent 2. Congenital Scoliosis 1. Failure of vertebral formation (hemivertebra) 2. Failure of segmentation (partial or complete bar) 3. Abnormal spinal canal or cord (myelodysplasia) 3. Neuromuscular Scoliosis 1. Neuropathic 2. Myopathic 4. Neurofibromatosis with Scoliosis 5. Scoliosis with disease of the vertebra (tumor, infection, metabolic disease, arthritis) Etiology A. Non-structural Scoliosis 1. Postural 2. Caused by LLD 3. Caused by nerve root irritation 4. Caused by contractures about the hip 5. Muscle guarding Non-Structural Scoliosis  Spinal curvatures are the result of temporary postural influences  Functional or non- structual scoliosis is not accompanied by rational or asymmetric changes in the individual structures of the spine Potential Muscle Impairments  Mobility impairment in structures on the concave side of the curves.  Stretch and weakness in the musculature on the convex side of the curves  If one hip is adducted, the adductor muscles on that side have decreased flexibility and the abductor muscles are stretched and weak  With advanced structural scoliosis, cardiopulmonary impairment may restrict function Potential Sources of Symptoms:  Muscle fatigue and ligamentous strain on the side of the convexity  Nerve root irritation on the side on the concavity Scoliosis Pathology:  All the structures of the concave side are compressed/ shortened  Apical vertebra – situated in the middle of the curve; has the greatest change, being wedge-shaped & most rotated Scoliosis Pathology:  IV discs – compressed on the concave side; may bulge on the convex side  ALL maybe thickened on the concave side and thinned on the convex side  In later stage, ossification of ligaments may occur; DJD Scoliosis Pathology:  Rotation is greatest in the apical vertebra  Vertebral body turns towards the convex side of the curve; spinous process toward the concavity  Rib Hump Etiology of Pain (Effect of Mechanical Stress)  The ligaments, facet capsules, periosteum of the vertebrae, muscles, anterior dura mater, dural sleeves, epidural areolar adipose tissue, and walls of blood vessels are innervated and responsive to nociceptive stimuli Effect of Impaired Postural Support from Trunk Muscles  With total relaxation of muscles, the spinal curves become exaggerated, and passive structural support is called on to maintain the posture  Continual exaggeration of the curves leads to postural impairment and muscle strength and flexibility imbalances as well as other soft tissue restrictions or hypermobility Effect of Impaired Postural Support from Trunk Muscles  stretch weakness - muscles that are habitually kept in a stretched position tend to test weaker because of a shift in the length-tension curve  tight weakness - Muscles kept in a habitually shortened position tend to lose their elasticity; weakens when lengthened and strong when shortened Effect of Impaired Muscle Endurance  Sustained postures require continual, small adaptations in the stabilizing muscles to support the trunk against fluctuating forces  as the muscles fatigue, the mechanics of performance change and the load is shifted to the inert tissues supporting the spine at the end ranges Pain Syndromes Related to Impaired Posture Postural Fault  is a posture that deviates from normal alignment but has no structural limitations Pain Syndromes Related to Impaired Posture Postural Pain Syndrome  refers to the pain that results from mechanical stress when a person maintains a faulty posture for a prolonged period  the pain is usually relieved with activity  strength and flexibility imbalances eventually develop  reversible Pain Syndromes Related to Impaired Posture Postural Dysfunction  differs from the postural pain syndrome in that adaptive shortening of soft tissues and muscle weakness are involved  Stress to the shortened structures causes pain.  not relieved by a change of activity The head, neck, thorax, lumbar spine, and pelvis are all interrelated; and deviations in one region affect the other areas COMMON FAULTY POSTURES: CHARACTERISTICS AND IMPAIRMENTS Lordotic Posture  characterized by an increase in the lumbosacral angle (the angle that the superior border of the first sacral vertebral body makes with the horizontal, which optimally is 30deg), Lordotic Posture  increase in lumbar lordosis  an increase in the anterior pelvic tilt and hip flexion  It is often seen with increased thoracic kyphosis and forward head and is called kypholordotic posture. Lordotic Posture Potential Muscle Impairments  Tight hip flexor muscles  stretched and weak abdominal muscles Lordotic Posture Potential Sources of Symptoms  Stress to the anterior longitudinal ligament.  Narrowing of the posterior disk space and narrowing of the intervertebral foramen  Approximation of the articular facets. The facets may become weight bearing, which may cause synovial irritation and joint inflammation Lordotic Posture Common Causes  Sustained faulty posture, pregnancy, obesity, and weak abdominal muscles 2 Common Causes (Brashear): 1. Abnormal dorsal kyphosis 2. Hip flexion contracture Relaxed or Slouched Posture  is also called swayback  characterized by excessive shifting of the pelvic segment anteriorly, resulting in hip extension, and shifting of the thoracic segment posteriorly, resulting in flexion of the thorax on the upper lumbar spine Relaxed or Slouched Posture  results in increased lordosis in the lower lumbar region, increased kyphosis in the thoracic region, and usually a forward head  When standing for prolonged periods, the person usually assumes an asymmetrical stance in which most of the weight is borne on one lower extremity with pelvic drop (lateral tilt) and hip abduction on the unweighted side Relaxed or Slouched Posture Potential Muscle Impairments  Tight upper abdominal muscles (upper segments of the rectus abdominis and obliques), internal intercostal, hip extensor, and lower lumbar extensor muscles and related fascia  stretched and weak lower abdominal muscles (lower segments of the rectus abdominis and obliques), extensor muscles of the lower thoracic region, and hip flexor muscles Relaxed or Slouched Posture Potential Sources of Symptoms  Stress to the iliofemoral ligaments, the anterior longitudinal ligament of the lower lumbar spine, and the posterior longitudinal ligament of the upper lumbar and thoracic spine  With asymmetrical postures, there is also stress to the iliotibial band on the side of the elevated hip  Narrowing of the intervertebral foramen in the lower lumbar spine  Approximation of articular facets in the lower lumbar  spine. Relaxed or Slouched Posture Common Causes  relaxed posture in which the muscles are not used to provide support  The person yields fully to the effects of gravity, and only the passive structures at the end of each joint range provide stability  may be attitudinal, fatigue, or muscle weakness Flat Low-Back Posture  characterized by a decreased lumbosacral angle, decreased lumbar lordosis, hip extension, and posterior tilting of the pelvis Flat Low-Back Posture Potential Muscle Impairments  Tight trunk flexor and hip extensor muscles  Stretched and weak lumbar extensor and possibly hip flexor muscles Flat Low-Back Posture Potential Sources of Symptoms  Lack of the normal physiological lumbar curve, which reduces the shock-absorbing effect of the lumbar region and predisposes the person to injury  Stress to the posterior longitudinal ligament  Increase of the posterior disk space, which allows the nucleus pulposus to imbibe extra fluid and, under certain circumstances, may protrude posteriorly when the person attempts extension Flat Low-Back Posture Common Causes:  Continued slouching or flexing in sitting or standing postures; overemphasis on flexion exercises in general exercise programs Round Back (Increased Kyphosis) with Forward Head  characterized by an increased thoracic curve, protracted scapulae (round shoulders), and forward (protracted) head forward head  involves increased flexion of the lower cervical and the upper thoracic regions, increased extension of the upper cervical vertebra, and extension of the occiput on C1. Round Back (Increased Kyphosis) with Forward Head Potential Muscle Impairments  Tight muscles of the anterior thorax, muscles of the upper extremity originating on the thorax, muscles of the cervical spine and head that attached to the scapula and upper thorax (levator scapulae, sternocleidomastoid, scalene, upper trapezius), and muscles of the suboccipital region (rectus capitis posterior major and minor, obliquus capitisinferior and superior). Round Back (Increased Kyphosis) with Forward Head Potential Muscle Impairments  stretched and weak lower cervical and upper thoracic erector spinae and scapular retractor muscles (rhomboids, middle trapezius), anterior throat muscles (suprahyoid and infrahyoid muscles), and capital flexors (rectus capitis anterior andlateralis, superior oblique longus colli, longus capitis Round Back (Increased Kyphosis) with Forward Head Potential Muscle Impairments  With temporomandibular joint symptoms, the muscles of mastication may have increased tension (pterygoid, masseter, temporalis muscles). Round Back (Increased Kyphosis) with Forward Head Potential Sources of Symptoms  Stress to the anterior longitudinal ligament in the upper cervical spine and posterior longitudinal ligament in the lower cervical and thoracic spine  Fatigue of the thoracic erector spinae and scapular retractor muscles  Irritation of facet joints in the upper cervical spine Round Back (Increased Kyphosis) with Forward Head Potential Sources of Symptoms  Narrowing of the intervertebral foramina in the upper cervical region  Impingement on the neurovascular bundle from anterior scalene or pectoralis minor muscle tightness  Strain on the neurovascular structures of the thoracic outlet from scapular protraction Round Back (Increased Kyphosis) with Forward Head Potential Sources of Symptoms  Impingement of the cervical plexus from levator scapulae muscle tightness  Impingement on the greater occipital nerves from a tight or tense upper trapezius muscle, leading to tension headaches  Temporomandibular joint pain from faulty head, neck, and mandibular alignment and associated facial muscle tension  Lower cervical disk lesions from the faulty flexed posture Round Back (Increased Kyphosis) with Forward Head Common Causes  effects of gravity, slouching, and poor ergonomic alignment in the work or home environment  occupational or functional postures requiring leaning forward or tipping the head backward for extended periods, faulty sitting postures, relaxed postures, or the end result of a faulty pelvic and lumbar spine posture  continued slouching, and overemphasis on flexion exercises in general exercise programs Kyphosis  Anteroposterior curvature of the spine in which convexity is directed posteriorly CAUSES:  Faulty posture – frequent cause  Chronic arthritis  Pott’s disease Other Disease Entities that may Cause Kyphosis: Adolescent Kyphosis (Scheuermann’s Disease, Juvenile Kyphosis, Vertebral Epiphysitis)  Chronic affectation pf the vertebral bodies  Gradual development of fixed kyphosis  Onset is on early teens Other Disease Entities that may Cause Kyphosis:  Vertebra Plana (Eosinophilic Granuloma, Calve’s Disease)  Uncommon affectation occurring mostly in children between 2 & 12 years  Ischemic necrosis localized in single vertebra  A pathologic fx caused by a benign eosinophilic granuloma Other Disease Entities that may Cause Kyphosis: Adult Kyphosis  Produced by faulty posture  IV disc degeneration (senile kyphosis)  Atrophy & collapse of vertebral bodies (postmenopausal and senile OA) Flat Upper Back and Neck Posture  characterized by a decrease in the thoracic curve, depressed scapulae, depressed clavicles, and decreased cervical lordosis with increased flexion of the occiput on atlas Flat Upper Back and Neck Posture Potential Muscle Impairments  Tight anterior neck muscles, thoracic erector spinae and scapular retractors, and potentially restricted scapular movement, which decreases the freedom of shoulder elevation  Impaired muscle performance in the scapular protractor and intercostal muscles of the anterior thorax Flat Upper Back and Neck Posture Potential Sources of Symptoms  Fatigue of muscles required to maintain the posture  Compression of the neurovascular bundle in the thoracic outlet between the clavicle and ribs  Temporomandibular joint pain and occlusive changes.  Decrease in the shock-absorbing function of the kypholordotic curvature, which may predispose the neck to injury. Flat Upper Back and Neck Posture Common Causes  this is not a common postural deviation and occurs primarily with exaggeration of the military posture Refences  Houglum, P. A., & Bertoti, D. B. (2011). Brunnstrom's clinical kinesiology. FA Davis.  Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function: a comprehensive analysis.  Kisner, C., Colby, L. A., & Borstad, J. (2017). Therapeutic exercise: foundations and techniques. Fa Davis.  https://www.youtube.com/watch?v=Zp5iC3I oq7U