Spine Overview & Cervical Spine Part 2 PDF

Spine overview & Cervical spine Part II Assistant Prof. Dr. Ghada Omar 1 Objectives (ILOs) After studying this lecture, the students will be able to: 1. Understand the major structures & functions of the spinal column. 2. Identify the main struct...

Spine overview & Cervical spine Part II Assistant Prof. Dr. Ghada Omar 1 Objectives (ILOs) After studying this lecture, the students will be able to: 1. Understand the major structures & functions of the spinal column. 2. Identify the main structures of the cervical spine, including bones, joints, some special structures, & deep & superficial muscles. 3. Label & palpate the major surface landmarks of the cervical spine. 4. Identify & demonstrate all actions of the muscles acting on cervical spine. 5. Locate the attachments & nerve supply of the muscles acting on cervical spine. 2 " Muscles of the Neck" https://www.getbodysmart.c om/neck-muscles/ https://www.youtube.com/w atch?v=tHMvTWq4MPU&ab _channel=Corporis https://www.youtube.com/w atch?v=IxInfkIfn0E&ab_chan nel=TheNotedAnatomist 3 Cervical spine muscle attachments Anterior View Lateral View Shown here are the cervical muscles that Shown here are cranial & cervical muscles that attach to the front of the spine, hyoid, & attach to the side of the spine, hyoid, & shoulder girdle. shoulder girdle. 4 Cervical spine muscle attachments: Posterior view 5  Superficial cervical muscles: anterolateral view The superficial muscles of the anterior neck serve multiple purposes. They are large, thick, & broad forming a cape-like structure spanning the clavicles, base of the skull, & upper spine. They protect underlying structures & suspend the shoulder girdle from the head. These large muscles on the front of the neck produce gross movement in this region including flexion, lateral flexion, & rotation. 6  Superficial cervical muscles: posterior view The kite-shaped trapezius muscle dominates the posterior neck & can move the head, neck, & scapula. Directly underneath the trapezius is the splenius capitis & splenius cervicis. These muscles extend, laterally bend, & rotate the head toward the shoulder. 7 Intermediate cervical muscles: anterior view The muscles of swallowing dominate the central layer of muscle in the front of the neck. These include the suprahyoid & infrahyoid muscles, named for their relative location to the hyoid bone. This group of muscles assists during chewing, swallowing, & speaking. These muscles flex, laterally bend, & rotate the head toward the shoulder. 8 Intermediate cervical muscles: posterior view The central layer of muscles in the back of the neck contains longer & broader muscles. These span multiple joints & produce gross movements in this region including: extension, lateral flexion, & rotation. 9 Deep cervical muscles: anterior view Several deep muscles connect the anterior surfaces of the skull & vertebrae. These muscles maintain the alignment of the cervical vertebrae & perform fine flexion & lateral flexion movements in this region. 10 Deep cervical muscles: posterior view The suboccipital & semispinalis muscles of the neck work with the rotatores & multifidi, other deep spinal muscles, to stabilize the head & neck posteriorly. These small, specialized muscles maintain the alignment of the skull & cervical vertebrae. They also perform fine extension lateral flexion, & rotational movements in this region. 11 Muscles of the Spine Cervical Anterior Sternocleidomastoid Scalene anterior, middle & posterior Platysma Longus colli Longus capitis Rectus capitus anterior 12 Sternocleidomastoid Greek "sternon" chest "kleis“ clavicle "mastos" breast "eidos" resemblance Attachments O: Sternal head: superior manubrium O: Clavicular head: medial one-third I: Temporal bone, lateral mastoid process I: Occipital bone, lateral one-half of superior nuchal line 13 Sternocleidomastoid Actions: Flexes the neck (bilateral action) Laterally flexes the head & neck (unilateral action) Rotates the head & neck toward opposite side (unilateral action) Innervations: Accessory nerve C1 & C2 14 Functional Anatomy: Sternocleidomastoid The sternocleidomastoid is one of the largest & most superficial muscles in the neck. It has two heads & connects the mastoid process of the temporal bone to the manubrium of the sternum & medial clavicle. The sternocleidomastoid runs parallel to the ramus of the mandible & forms an inverted "v" with the splenius capitis. These two muscles center the head front-to-back over the shoulder girdle. Sternocleidomastoid's strong attachment to the mastoid process of the temporal bone & oblique position on the neck make it a powerful prime mover for flexion, lateral flexion, & rotation of the head & neck. This combination of flexion of the neck & extension of the head creates head movement forward, leading with the chin. Tightness in this muscle, if bilateral, can lead to a forward head posture &, if unilateral, to a condition called torticollis (a laterally flexed & rotated neck). 15  Scalenes Greek "skalenos" uneven Attachments O: C3-C6, anterior tubercles of transverse processes (anterior) O: C2-C7, posterior tubercles of transverse processes (middle) O: C5-C7, posterior tubercles of transverse processes (posterior) I: 1st rib, inner upper edge (anterior) I: 1st rib, outer upper edge (middle) I: 2nd rib, lateral surface (posterior) 16 Scalenes Actions Flexes the head & neck (bilateral action) anterior only Laterally flexes the head & neck (unilateral action) Rotates the head & neck toward opposite side (unilateral action) Elevates 1st & 2nd rib during forced inhalation Innervation Cervical spinal nerves C6-8 17 Functional Anatomy: Scalenes The scalenes consist of three parts: the anterior, middle, & posterior scalenes & located laterally on the neck. These muscles work together to laterally flex & stabilize the head & neck. They also form a protective cape surrounding deeper structures such as the vertebral artery, jugular vein, & brachial plexus. The scalenes branch to attach to the second rib laterally & the first rib laterally & anteriorly. This dispersion of insertions allows the anterior scalene to flex & rotate the head & neck while the other portions laterally flex. When the head & neck are fixed, the scalenes can elevate the first & second rib during inhalation. This elevation increases the space in the thoracic cavity, prompting greater inflow of air to the lungs. This occurs more often during labored breathing (during heavy exercise or with pulmonary pathology such as asthma). Excessive tightness, hypertrophy (e.g., from overuse), trauma, or structural abnormality of the scalenes can lead to compression of the structures it protects, such as the brachial plexus or subclavian artery. This general pathology is called thoracic outlet syndrome. 18 Platysma Greek "platy" flat Attachments O: Fascia of superior pectoralis major & deltoid muscles I: Mandible, inferior border Actions: Flexes the head & neck (bilateral action) Innervation: Facial nerve 19 Functional Anatomy: Platysma Platysma functions primarily in facial expression. It is the most superficial muscle of the anterior neck & extends from the mandible & fascia of the face. Its insertion is not bony; rather, it is attached to the fascia of the chest & the anterior shoulder girdle. Platysma is a flat, continuous sheet of muscle (generally termed a panniculus muscle). Panniculus muscles are found in many animals & perform functions like flicking flies or raising hair. In humans, platysma draws the lower lip downward & laterally while creating ridges or wrinkles in the skin of the neck & chest. This action characterizes facial expressions of stress or anger. 20 Longus Colli Latin "longus" long "colli" neck Attachments O: C3-C5, anterior tubercles of transverse processes & C5-T3, anterior surface of bodies I: C2-C6, anterior surfaces 21 Longus Colli Actions: Flexes the head & neck (bilateral action) Laterally flexes the head & neck (unilateral action) Rotates the head & neck toward same side (unilateral action) Innervation: C2-C7 22 Functional Anatomy: Longus Colli The deepest of the anterior neck muscles, the longus colli is long & primarily vertical with multiple segments. It creates an interconnecting network between the anterior surfaces of the cervical & upper thoracic vertebrae. This muscle is a strong flexor of the head & neck when both sides fire, as it spans all of the cervical vertebrae. The longus colli is often associated with the rectus capitis anterior & rectus capitis lateralis as the paravertebral group. This group helps stabilize the anterior neck during high-intensity activities like sneezing & rapid arm movements like throwing. It also actively stabilizes the front of the curve of the neck, keeping the head from falling back. Longus colli is clearly divided into right & left sides with a gap at the midline of the vertebral bodies. This creates some leverage for lateral flexion. Slight horizontal fiber orientation in its superior & inferior segments generates slight rotation to the opposite side when longus colli fires unilaterally. 23 Longus Capitis Greek "platy" flat Attachments O: C3-C6, anterior tubercles of transverse processes I: Occipital bone, inferior surface of basilar part Actions: Flexes the head & neck (bilateral action) Rotates the head & neck toward same side (unilateral action) Innervation: C1-C3 24 Functional Anatomy: Longus Capitis Like longus colli, the longus capitis is deep to the hyoid bone, suprahyoid muscles, trachea, & oesophagus. Its fibers lie more superiorly & run more obliquely than those of longus colli & connect the occiput to the transverse processes of the middle cervical vertebrae. This oblique fiber orientation gives longus capitis better leverage for rotation when firing one side at a time. Longus capitis also is one of several muscles that attaches to the occiput and so affects positioning & movement at the atlanto- occipital joint. Like longus colli, longus capitis is part of the paravertebral group. This group helps stabilize the anterior neck & keep the head from falling back. 25 Muscles of the Cervical Spine Cervical Posterior Splenius capitis & cervicis Rectus Capitis posterior major/minor Longissimus capitus Iliocostalis cervicis 26 Splenius Capitis Latin "splenius" bandage " Capitis " head Attachment: O: Ligamentum nuchae & C7-T3, spinous processes I: Temporal bone, mastoid process & occiput, lateral portion of superior nuchal line Actions: Extends the head (bilateral action) Laterally flexes the head & neck (unilateral action) Rotates the head toward same side (unilateral action) Innervation: Cervical spinal nerves 27  Functional Anatomy: Splenius Capitis Splenius capitus is deep to the trapezius & has a broad origin on the nuchal ligament & spinous processes of the lower cervical & upper thoracic vertebrae. It narrows & thickens to form a strong attachment on the mastoid process & lateral occiput. This muscle forms a strong counterbalance to the large sternocleidomastoid on the front of the neck. Laterally, these two muscles form an inverted "v" & center the head front-to- back over the shoulder girdle when balanced. Compared to the deeper suboccipitals, the splenius capitus is large & broad, making it a more effective prime mover for extension, lateral flexion, & rotation of the head & neck. It is a direct synergist to the splenius cervicis but has better leverage for lateral flexion & rotation as it attaches more laterally & superiorly than cervicis. 28 Splenius Cervicis Latin "splenius" bandage "cervicis" neck Attachment: O: T3-T6, spinous processes I: C2-C3, posterior tubercles of transverse processes Actions: Extends the head (bilateral action) Laterally flexes the head & neck (unilateral action) Rotates the head toward same side (unilateral action) Innervation: Cervical spinal nerves 29 Functional Anatomy: Splenius Cervicis Splenius cervicis connects the spinous processes of the upper thoracic vertebrae to the transverse processes of the upper cervical vertebrae. Its fiber orientation—vertical, slightly oblique—make it a powerful extensor & weak rotator of the cervical spine. It shares its attachments on the cervical transverse processes with the levator scapula posteriorly & the scalenes anteriorly. Proper balance in strength & flexibility in these three muscles maximizes cervical alignment & function. The splenius cervicis is a direct synergist to the splenius capitis but has less leverage for rotation than its more obliquely oriented counterpart. It also lies just superficial to splenius capitis & levator scapula. 30 Semispinalis Latin "semi" half "spinalis" spinous process Attachment: O: C4-C6, articular processes & C7- T10, transverse processes I: Occiput, between superior & inferior nuchal lines & C2-T4, spinous process Actions: Extends the head (bilateral action) Laterally flexes the head & neck (unilateral action) Rotates the head toward opposite side (unilateral action) Innervation: Cervical & thoracic spinal nerves 31 Functional Anatomy: Semispinalis The semispinalis lies deep to the trapezius & just superficial to the deep, stabilizing suboccipital muscles. Its several divisions include the capitis (attaching to the occiput), cervicis (attaching to the cervical vertebrae), & thoracis (attaching to the thoracic vertebrae). Each segment spans five or six vertebrae attaching inferiorly to the transverse processes & superiorly to the spinous processes or occiput (in the case of capitis). The vertical fibers of semispinalis make it a strong extensor of the head & neck & a weak rotator. The semispinalis is one of several postural muscles that hold the head upright against gravity. Tightness in this muscle or imbalances in strength between it & its antagonist flexors can compress the associated occipital nerve, creating headaches felt in the back of the head. 32 SYNERGISTS/ANTAGONISTS: Neck Motion Muscles Involved Flexion Sternocleidomastoid Platysma Longus colli Longus capitis Scalenes (anterior fibers) Rectus capitis anterior Motion Muscles Involved Extension Sternocleidomastoid (upper cervicals only) Splenius capitis Splenius cervicis Semispinalis Rectus capitis posterior major Rectus capitis posterior minor Obliquus capitis superior Levator scapula Trapezius 33 SYNERGISTS/ANTAGONISTS: Neck Motion Muscles Involved Lateral Flexion Right sternocleidomastoid (Right) Right scalenes Right longus colli Right splenius capitis Right splenius cervicis Right semispinalis Right obliquus capitis superior Right rectus capitis lateralis Motion Muscles Involved Lateral Flexion Left sternocleidomastoid (Left) Left scalenes Left longus colli Left splenius capitis Left splenius cervicis Left semispinalis Left obliquus capitis superior Left rectus capitis lateralis 34 SYNERGISTS/ANTAGONISTS: Neck Motion Muscles Involved Rotation (Right) Left sternocleidomastoid Left scalene Right longus colli Right longus capitis Right splenius capitis Right splenius cervicis Left semispinalis Right rectus capitis posterior major Right obliquus capitis inferior Right rectus capitis anterior Right levator scapula Motion Muscles Involved Rotation (Left) Right sternocleidomastoid Right scalene Left longus colli Left longus capitis Left splenius capitis Left splenius cervicis Right semispinalis Left rectus capitis posterior major Left obliquus capitis inferior Left rectus capitis anterior Left levator scapula 35 Practical part Palpation of the bony landmarks of the Cervical spine. Illustrating function and Palpating of anterior & posterior neck muscles. Knowledge of nerve supply 36 References Cael C, (2011) “Functional Anatomy: Musculoskeletal Anatomy, Kinesiology, & Palpation for Manual Therapists. “ Chapter 6, Lippincott Williams & Wilkins. Levangie PK, Norkin CC, (2005) “Joint Structure & Function: A Comprehensive Analysis.”, Chapter 4, 4th ed. Philadelphia, FA Davis Co. Olson, K.A. (2009). Manual physical therapy of the spine, Chapter 6 , Saunders, Elsevier Inc. Missouri, USA. Kisner, C. & Colby, L.A. (2002). Therapeutic exercise: Foundations & techniques, 4th ed. F.A. Davis: Philadelphia. Gray’s Anatomy: http://www.bartleby.com/107/ http://www.spinecenteronline.com/educational_resources/anatomy_librar y.html http://www.mayfieldclinic.com/PE-AnatSpine.htm www.google.com (images) 37 Any Question ? ? 38 Thank You 39