The Cervical Spine (1).pdf

The Cervical Spine PP6012 Maria Hill Acknowledgements: Niamh Brady Learning Outcomes Review the structure and function of the vertebral column Discuss how various anatomical architectural features of the vertebral column and its joint structures play a role in movement and stability Describe typical...

The Cervical Spine PP6012 Maria Hill Acknowledgements: Niamh Brady Learning Outcomes Review the structure and function of the vertebral column Discuss how various anatomical architectural features of the vertebral column and its joint structures play a role in movement and stability Describe typical features of a vertebrae in the cervical spine Describe how the vertebrae articulate with each other at various joints and how the shape of these joints influence movement Discuss the ligaments that provide support of the cervical spine Discuss the muscles that support and move the cervical spine Functions of the Neck To house and protect the spinal cord To allow passage of important blood vessels and lymphatics to/from brain To house and protect important glands To support the cranium To enable diverse head movement Proprioception Oculomotor Control Postural Stability Respiration – Trachea Speech – Larynx/Pharynx Swallowing - Oesophagus Extensors Muscles Neck Pain The Cranium The role of the cranium is to: Encase and protect the brain Encase several essential sensory organs such as the eyes, ears, nose, tongue and vestibular system Provide attachment for muscles that control head and neck movement Contains the TMJ – what type of joint? 8 cranial bones and 14 facial bones The Cranium – anatomical landmarks Occipital Bone External Occipital Protuberance Foramen Magnum Nuchal Lines Occipital Condyles Foramen Magnum Occipital Condyle Inferior Nuchal Line Superior Nuchal Line External Occipital Protuberance The Cranium – anatomical landmarks Temporal Bone Mastoid Process External Auditory Meatus Styloid Process Zygomatic Process The “Back” Posterior neck and trunk Skin Fascia Muscle Ligament Vertebral Column Disc Thorax Blood Vessels Nerves The Vertebral Column (The Spine) Axial Skeleton – a flexible curved central axis of the skeleton (approx 70cm long in male) 33 vertebrae arranged in 5 regionally distinct groups 7 cervical 12 thoracic 5 lumbar 5 sacral (fused) 4 coccygeal (fused) Curvatures of the VC in the Adult Primary curvature (foetal) is flexed, 2 secondary curvatures develop after birth Cervical – development of head control/extensor muscles – cervical spine develops a lordosis Thoracic – Maintains primary curvature - kyphosis Lumbar – Development of upright posture produces a lumbar lordosis Sacrococcygeal – maintains primary curve - kyphosis Deviations from normal curvatures Maldevelopment or pathological Kyphosis Increased or Hyperkyphosis Associated with Osteoporosis Lordosis Hyperlordosis - neuromuscular Swayback Pregnancy Scoliosis Lateral S-Shaped curvature Accompanied by rotation of the vertebrae Features of a Typical Vertebra 2 main parts – body and neural arch Body Supports weight. Increased size with descent. Arch Pedicles (anterior) Laminae (posterior) Vertebral Foramen Form Spinal Canal Contain Spinal Cord, Meninges, Nerves, Blood Vessels Spinal cord is 40-45cm long, extending from foramen magnum to L1/2 spinal level Features of a typical vertebra Spinous Process x 1 Posterior projections, junction of laminae Transverse Process x 2 Posterolateral projections, junctions laminae and pedicles Articular Process x 4 X 2 superior, x 2 inferior Articulate with vertebrae superiorly and inferiorly – facet joints Intervertebral foramina Posterolateral to vertebral bodies, transmit spinal nerves and vessels Cervical Vertebra 7 cervical vertebrae C1, 2 & 7 Atypical C3-6 Typical C3-6 - Typical Vertebrae Foramen transversarium– through which ascending vertebral artery passes Small oval shaped vertebral bodies – lipped superolaterally to articulate with bevelled inferior margin of the vertebrae above Large triangular vertebral foramina and intervertebral foramina Bifid Spinous process Short transverse process (with anterior and posterior tubercles) Large rounded articular processes Superior facets face posteriorly and superiorly Inferior facets face anteriorly and inferiorly What does this mean for movement?? The Vertebral Artery Right and left vertebral arteries arise from the subclavian arteries They ascend through foramen transversarium They enter cranial cavity via foramen magnum They give off branches Meningeal, Spinal and cerebellar arteries They combine to form the basilar artery which supplies the cerebellum, pons and contributes to the circle of Willis C1 - Atlas No body, pedicle, lamina or spinous process Large transverse process – muscle attachment Ring formed by anterior & posterior arch & 2 lateral masses Superior articular facets articulate with occipital condyles – atlanto-occipital joint Inferior articular facets articulate with C2 articular processes Dens (C2) articulates with anterior arch to form atlanto-axial joint (C1/2) Transverse ligament between lateral masses C2 - Axis The Odontoid Process (Dens) projects superiorly to articulate with Atlas This articulation forms a vertical axis for rotation of the head (and atlas) on the axis – approx. 90 degrees Short transverse process Bifid spinous process Note: there is no disc between atlas and axis C7 – Vertebra Prominens Largest cervical vertebra Similar in shape to thoracic vertebrae Large non-bifid spinous process Clinical – Spinal Stenosis Spinal Stenosis is a narrowing of the spinal canal which reduces space for spinal cord and associated nerves Degenerative changes (ligament hypertrophy, disc degeneration, Osteophyte formation) Spinal tumours Congenital (Achondroplasia) Symptoms Extension related Radiculopathy Myelopathy Joints of the VC Intervertebral Facet or Zygapophyseal Uncovertebral (Cx) Atlanto-occipital/Craniovertebral (Cx) Atlanto-axial (Cx) Costovertebral (Tx) Costotransverse (Tx) Lumbosacral Sacroiliac Intervertebral Joints (IVJs) Between vertebral bodies Secondary cartilaginous Bone – Endplate – Disc – Endplate - Bone Function – designed for WB & movement Intervertebral Disc (IVD) Endplate Hyaline & fibrocartilage Diffusion of nutrients through endplate arteries Outer annulus fibrosis Rings of fibrocartilage – lamellae (20) Attaches rims of VB’s 60-70% water Inner nucleus pulposus Gelatinous (toothpaste) centre Cartilage cells, collagen fibres (Type II), semifluid ground substance – proteoglycan gel 70-90% water Clinical - Disc Herniation Disc Protrusion, Prolapse, Extrusion, Sequestration What is it? Tear of annular fibrosis, herniation of nucleus pulposus, make cause compression of neural structures Cause Dehydration, degeneration, loss of resilience Mechanism – flexion, rotation, load Direction Commonly posterolateral – thin annulus and weak PLL Cx Spine – C5/6 and C6/7 most common Ligaments of Spine Anterior Longitudinal Ligament Strong fibrous band Connects anterior aspects of vertebral bodies Function Stability Prevents Hyperextension Ligaments of Spine Posterior Longitudinal Ligament (PLL) Weaker than ALL Within vertebral canal Attaches to IVD’s Function Prevent Hyperflexion Prevent disc protrusion Facet joints (Zygapophyseal) Between articular facets of vertebrae Plane Synovial Joints Loose articular capsule Movements Gliding Orientation of articular facets Regional differences Cervical Spine ?? Facet Joint strain/arthritis Potential cause of neck pain Associated with disc degeneration MRI – narrowing of facet joint space and osteophyte formation Accessory Ligaments Ligamentum flavum Between adjacent laminae Limit flexion of VC Intertransverse ligament Between transverse processes Interspinous ligament Weak Between SP’s Accessory Ligaments Supraspinous Strong Between SP’s Merges with ligamentum Nuchae Ligamentum Nuchae Between Skull (Nuchal lines) and Cx SP’s Uncovertebral Joints Known as Joints of Luschka ? Joints or Pseudoarthrosis Facilitate flexion/extension Prevent posterior linear translation of vertebrae Atlanto-occipital Joint Ellipsoid synovial joints x 2 Articulating surfaces Occipital condyles and superior articular facets of C1 Lax joint capsule Designed for nodding movements Atlanto-axial Joint 3 Joints Pivot Synovial Joint – Between Dens and Anterior arch C1 Plane Synovial Joints – between C1 inferior (convex) and C2 superior (concave) articular processes Capsule Thick and loose, strengthened by accessory ligaments posteriorly and medially Designed for rotation Craniocervical Ligaments Transverse Ligament Thick, strong band Connects lateral masses to maintain position of the Dens Half of the cruciform ligament Cruciform Ligament Cross-shaped Horizontal portion made up of transverse ligament Vertical portion made up of longitudinal fibres Attach from anterior rim of foramen magnum to body of Axis Craniocervical Ligaments Alar Ligament Two strong rounded cords Odontoid Process to Occipital condyles Apical Ligament Odontoid Process to Anterior rim of foramen magnum Tectorial Membrane Strong, broad structure Continuous with PLL Posterior body of C2 to the basilar groove of the occipital bone, anterior to foramen magnum Clinical – Cranio-vertebral Instability Following trauma eg RTA Congenital Conditions: Downs Syndrome, Morquio Syndrome, Grisel Syndrome Systemic Inflammatory Conditions - Rheumatoid Arthritis Kinematics of Craniocervical Region Movement Degree of motion (approx) Plane of movemnet Axis Flexion 50 Sagittal Coronal Extension 80 Sagittal Rotation 90 Transverse Vertical Lateral Flexion 40 Coronal Sagittal Cervical Flexion Atlanto-occipital Joint: ConvexConcave rule Occipital condyles roll forwards and slide backwards Atlanto-axial Joint Ring shaped atlas tilts forwards (15 deg) Facet Joints Superior facets slide superiorly and anteriorly Cervical Extension Atlanto-occipital Joint: ConvexConcave rule Occipital condyles roll backwards and slide forwards Atlanto-axial Joint Ring shaped atlas tilts backwards (15 deg) Facet Joints Superior facets slide inferiorly and posteriorly Cervical Rotation Atlanto-occipital Joint: Not involved Atlanto-axial Joint Designed for maximal rotation – 8090 degrees Limited by alar ligaments Full rotation stretches both vertebral arteries Facet Joints Allow some sliding motion Cervical Lateral Flexion Atlanto-occipital Joint: Roll and slide motion – 5 degrees Atlanto-axial Joint Not involved Facet Joints Allow approx. 35 degrees in a sliding motion of one articular facet on another Cervical protraction/retraction Protraction involves simultaneous lower cervical flexion and upper cervical extension (forward-head posture) Retraction involves lower cervical extension and upper cervical flexion Spinal Coupling is the phenomenon where movement within any plane throughout the vertebral column is associated with an automatic movement in another plane. Spinal Coupling In the Typical Cervical Spine Lateral flexion is coupled with ipsilateral rotation Due to the 45 degree inclination of articular facets Movement occurs in the coronal (LF) and transverse (Rot) planes simultaneously Note: At craniovertebral level – a contralateral spinal coupling pattern exists ie. C0/1 lateral flexion accompanied by C1/2 contralateral rotation. This is a compensatory strategy to balance overall rotation of head/neck Neck Muscles Superficial Anterior AKA Intermediate Posterior Lateral Trapezius Sternocleidomastoid Levator Scapulae Anterior Scalene Splenius Cervicis/Capitus Middle Scalene Iliocostalis Cervicis Posterior Scalene Longissimus Cervicis/Capitus Spinalis Cervicis/Capitus Deep Anterior Posterior Longus Colli Semispinalis, Multifidus Longus Capitus Rectus Capitus Posterior Major Rectus Capitus Anterior Rectus Capitus Posterior Minor Rectus Capitus Lateralis Obliquus Capitus Superior Obliquus Capitus Inferior Lateral Role of muscles in the cervical spine 80% cervical stability provided by muscle system in mid-range and functional posture Deep sleeve of muscle envelopes cervical spine providing segmental control High density of muscle spindles in deep muscles – sensorimotor control Superficial muscles greater role in torque production Posterior Neck Muscles Superficial Splenius Capitus and Cervicis Intermediate Iliocostalis Cervicis, Longissimus Cervicis and Capitus, Spinalis Cervicis and Capitus Deep Semispinalis, Multifidus https://teachmeanatomy.info/back/muscles/intrinsic/ Splenius Cervicis Proximal/Superior attachment TP C1-4 Distal/Inferior attachment SP T3-6 Nerve Supply Posterior Rami spinal nerves C5-7 Action Cervical rotation, extension Splenius Capitus Proximal attachment Occiput – Sup nuchal line – Mastoid Process Distal attachment SP C7-T3 and Nuchal Ligament Nerve Supply Posterior Rami spinal nerves C3 & 4 Action Craniocervical rotation, extension Erector Spinae Columns: Iliocostalis, Longissimus, Spinalis Divisions: Iliocostalis Lumborum, Thoracis, Cervicis Longissimus Thoracis, Cervicis, Capitis Spinalis Thoracis, Cervicis, Capitis Iliocostalis (Cervicis) Proximal TP C4-6 Distal Rib angles 3-5 Nerve Supply Adjacent posterior rami Action Cervical Spine Extension, Rotation, Lateral Flexion - Ipsilateral Longissimus (Cervicis & Capitus) Proximal Cervicis – TP C2-6 Capitus – Mastoid Process Distal Cervicis - TP T1-5 Capitus – TP C5-7 Nerve Supply Adjacent posterior rami Action Cervical Spine Extension, Rotation, Lateral Flexion Ipsilateral Spinalis (Cervicis & Capitus) Highly variable if present, commonly blended with semispinalis Proximal Inferior Nuchal line of Occiput Distal SP C2-T4, Ligamentum Nuchae Nerve Supply Adjacent posterior rami Action Cervical Spine Extension, Rotation, Lateral Flexion Ipsilateral Semispinalis Proximal SP C2-T4 and Occiput Distal TP C4-7 & T1-T10 Nerve Supply Posterior rami of adjacent spinal nerves Action Extension and contralateral rotation Multifidus Proximal SP C2-7 Distal Superior articular process C4-7 Nerve Supply Posterior rami of adjacent spinal nerves Action Segmental stability, contralateral rotation and extension Suboccipital muscles Rectus capitus Major and Minor Obliquus Capitus Superior and Inferior Rectus Capitus Minor Proximal Occiput - inf nuchal line Distal Posterior arch atlas Nerve Supply Subocciptal N (posterior ramus C1) Action Upper Cervical Extension, Ipsilateral Rotation Rectus Capitus Minor Rectus Capitus Major Proximal Occiput – inf nuchal line Distal SP Axis (C2) Nerve Supply Subocciptal N (posterior ramus C1) Action Upper Cervical Extension, Ipsilateral Rotation Obliquus Capitus Superior Proximal Occiput (between superior and inferior nuchal lines) Distal TP Atlas (C1) Nerve Supply Subocciptal N (posterior ramus C1) Action Upper Cervical Extension, Ipsilateral Rotation Obliquus Capitus Inferior Proximal TP Atlas (C1) Distal SP Axis (C2) Nerve Supply Subocciptal N (posterior ramus C1) Action Upper Cervical Extension, Ipsilateral Rotation Lateral muscles of the neck Sternocleidomastoid Scalenes Anterior Middle Posterior Anterior Scalene Proximal Anterior tubercles TP C3-6 Distal Scalene tubercle 1st Rib Nerve Supply Anterior Rami C5-6 Action Elevation 1st rib, Cervical lateral flexion, Flexion Middle Scalene Proximal Posterior tubercles TP C2-7 Distal Scalene tubercle 1st Rib Nerve Supply Anterior Rami C3-8 Action Elevation 1st rib, Cervical lateral flexion Posterior Scalene Proximal Posterior tubercles TP C5-7 Distal Scalene tubercle 2nd Rib Nerve Supply Anterior Rami C6-8 Action Elevation 2nd rib, Cervical lateral flexion Sternocleidomastoid Proximal Mastoid Process Distal 2 heads: Medial Clavicle, Manubrium of sternum Nerve Supply Accessory nerve (XI) Action Contralateral Rotation, Flexion Anterior Muscles of the Neck Deep Neck Flexors Longus Colli (cervicis) Longus Capitus Rectus Capitus Anterior Rectus Capitus Lateralis Rectus Capitus Lateralis Longus Capitus Longus Colli Rectus Capitus Anterior Longus Colli Proximal Vertebral Bodies C1 – T4 Distal Transverse Processes C3-6 Nerve Supply Anterior Rami C2-6 Action Flexion of neck Longus Colli Longus Capitus Proximal Base of occiput Distal TP C3-5 Nerve Supply Anterior Rami C1-4 Action Flexion of head Longus Capitus Rectus Capitus Anterior Proximal Base of occiput Distal Anterior arch atlas Nerve Supply Anterior Rami C1-2 Action Flexion of head on neck (nodding) Rectus Capitus Anterior Rectus Capitus Lateralis Proximal Jugular process of occiput Distal TP atlas Nerve Supply Anterior Rami C1 Action Lateral flexion of head on neck, stabilises head on neck Rectus Capitus Lateralis The Triangles of the Neck The Anterior Triangle Borders Superiorly – Mandible Laterally – Sternocleidomastoid Medially - Midline of neck Contents Muscles – next slide Nerves – Facial (VII), Glossopharyngeal (IX), Vagus (X), Accessory (XI), Hypoglossal (XII) Arteries – Common carotid, External & Internal branches Veins – Internal Jugular Vein Lymph nodes Muscles of the Anterior Triangle Suprahyoid Muscles Infrahyoid Muscles Stylohyoid Omohyoid Mylohyoid Sternohyoid Geniohyoid Thyrohyoid Digastric Sternothyroid Carotid Triangle Submental Triangle Muscular Triangle Submandibular Triangle The Triangles of the Neck The Posterior Triangle Borders Anterior – Sternocleidomastoid Posterior – Trapezius Inferior - Clavicle Contents Muscles – Omohyoid, Splenius Capitus, Levator Scapulae, Scalenes Nerves – Cervical Plexus, Phrenic (C3-5), Accessory (XI), Brachial Plexus Trunks Arteries – Subclavian Veins – External Jugular, Subclavian, Transverse scapular, suprascapular Lymph nodes Clinical Conditions Facet Strain/Arthritis Spinal Stenosis Disc Herniation Myogenic Strain Cervical radiculopathy Spinal Cord Compression Cervicogenic Headaches Cervicogenic Dizziness (as opposed to vestibular or vascular) Vertebrobasilar Insufficiency (VBI) Craniocervical Instability TMJ Dysfunction Whiplash Associated Disorder (WAD) http://www.chrisworsfold.com/