Vertebral Column Osteology PDF

Vertebral column: Osteology Prof Nanette Briers Head: Division of Clinical Anatomy [email protected] Room 4015, Level 4, Tygerberg Campus  Learning Outcomes  The vertebral column and back: 1. Name the functions of the vertebral column. 2. Describe the ty...

Vertebral column: Osteology Prof Nanette Briers Head: Division of Clinical Anatomy [email protected] Room 4015, Level 4, Tygerberg Campus  Learning Outcomes  The vertebral column and back: 1. Name the functions of the vertebral column. 2. Describe the typical characteristics of the vertebral column. 3. Describe the characteristics of a typical vertebra as well as the regional (cervical; thoracic; lumbar; sacral; coccygeal) characteristics of vertebrae. 4. Name, identify and classify all the joints of the vertebral column. 5. Discuss the anatomy of the atlanto-occipital and atlanto-axial joints (aka craniovertebral joints), intervertebral and sacroiliac joints. 6. Name and identify all the ligaments involved in the vertebral column. 7. Name, identify and classify the extrinsic and intrinsic back muscles and indicate in which movements of the vertebral column these muscles are involved in.  Vertebral column & Joints PART I: Vertebral column PART II: Joints  General structure and  Intervertebral joints function  Central intervertebral  Typical vertebrae joint  Cervical  Craniovertebral joints  Thoracic  Sacroiliac joint  Lumbar  Sacrum  Atypical vertebrae  Curvatures  Ligaments of the vertebral column Copyright Material which is made available by way of an electronic database may be subject to certain licensing conditions. These conditions normally entail that you may only use the material for your own private study and research at the University and not for any other purpose. It is expected of you to adhere to these conditions at all times. Printed material is also only made available for class discussion, private study and research purposes. Further reproduction of such material is prohibited. Slides may not be shared on open or closed websites. TEXT BOOKS  Moore KL, Dalley AF, Agur AMR (2014) Back. In: Clinically orientated anatomy (7th ed). Lippincott Williams & Wilkins; p439-507.  Drake RL, Vogl AW, Mitchel AWM (2015) Upper limb. In: Gray’s anatomy for students (3rd edition). Canada: Churchill Livingstone; p 683-834.  HUMAN SKELETON APPENDICULAR SKELETON AXIAL SKELETON  Shoulder girdle  Cranium, mandible, hyoid bone  Upper limb  Sternum  Pelvic girdle  Ribs (x12 pairs)  Lower limb  Vertebral column  BONE CLASSIFICATION  Long bones  Short bones  Sesamoid bones  Flat bones  Irregular bones: Vertebrae  Pneumatic bones  Overview Structure: Vertebral column consists of cervical (7), thoracic (12), lumbar (5), sacrum (5 fused), coccyx (4 rudimentary) Functions:  Attachment for limbs & head  Protects the spinal cord and nerves  Supports weight of the body superior to the level of the pelvis  Provides a partly rigid partly flexible axis for the body  Extended base on which the head is placed and pivots  Plays an important role in posture and locomotion  TYPICAL VERTEBRA Components:  Vertebral body  Vertebral arch  Pedicles (x2)  Lamina (x2)  Processes  Spinous process  Transverse processes (x2)  Articular processes (x4)  Superior articular facets  Inferior articular facets  Vertebral foramen  Intervertebral foramen  Superior vertebral notch  Inferior vertebral notch  TYPICAL VERTEBRA Components:  Vertebral body  Vertebral arch  Pedicles (x2)  Lamina (x2)  Spinous process  Transverse processes (x2)  Articular processes (x4)  Superior articular facets  Inferior articular facets  Vertebral foramen  Intervertebral foramen  Superior vertebral notch  Inferior vertebral notch  1. ID of vertebrae: TYPICAL VERTEBRAE https://www.youtube.com/watch?v=V4qkP8nF Mys 2, Superior facet joints: https://www.youtube.com/watch?v=8zQv2w WcrF0 C3-C6 T2-T8 L1 - L4 TYPICAL VERTEBRAE 1. ID of vertebrae: https://www.youtube.com/watch?v=V4qkP8nFM ys 2, Superior facet joints: https://www.youtube.com/watch?v=8zQv2wWcr F0 Inferior articular process and facet BUM: Free flexion & extension, BUL: Greatest degree of rotation, BM: Flexion & extension, lateral some lateral flexion, restricted some lateral flexion flexion, NO rotation rotation C3-C6 T2-T8 L1 - L4  Lamina Broad and overlapping Short and wide Long and thin T2-T8 L1 - L4 C3-C6 Posterior view  LUMBAR PUNCTURE  Extraction of cerebrospinal fluid (CSF) from lumbar cistern  Important diagnostic tool e.g.: Meningitis  Back flexed  Spreading laminae  Spreading spinous processes  Stretching ligamentum flavum  Spinal cord  Adults  End of spinal cord: L1/L2  Lumbar puncture: Between spinous processes of L3/L4  Infants:  End of spinal cord: L3/4  Lumbar puncture: Between spinous processes of L4/L5 LUMBAR PUNCTURE L1 L1 L2 L2 L3 L3 L4 L4 L5 L5  Relations of the spinal needle – horizontal section 1 Skin 2 Subcutaneous tissue A 3 Spinous process 4 Laminae 5 Ligamentum flavum Vertebral body 6 Epidural space Dura mater IVC 7 8 Subarachnoid space 9 Spinal nerves 10 Click to insert needle  ATYPICAL CERVICAL VERTEBRAE Groove for vertebral artery to enter foramen magnum AXIS (C2) Body No body, pedicle, spinous process, laminae Dens/ Odontoid process: axis for C1 rotation 2 Lateral masses Articular facets Articular facet Superior: flat, oval Superior: kidney shaped, concave Inferior: project ventrally (anterior Inferior: oval, flat and inferior) Arches ATLAS (C1) Transverse process Anterior Transverse foramen for vertebral Posterior: groove for artery vertebral artery and C1 No tubercles Transverse processes Spinous process Extend further laterally than other cervical vertebrae Large, bifid: felt in nuchal groove ATYPICAL VERTEBRAE C4 (typical) C7 (vertebrae prominence; atypical) Thoracic feature: Long spinous process Cervical features:  Transverse foramen, but vertebral artery does not pass through it  Rectangular vertebral body  Triangular vertebral foramen ATYPICAL THORACIC VERTEBRAE T1; T10 – T12 Long spinous process shape resembles C7 ATYPICAL LUMBAR VERTEBRAE L5 L5:  Massive body and transverse processes  Largest of all moveable vertebrae; weight bearing  Wedge shape IV disc between L5 and S1  Responsible for lumbosacral angle  CURVATURES  Fx: Shock absorbing, flexibility  Primary curvature:  Concave (ant): Thoracic, Sacrococcygeal  Differential height of the anterior and posterior aspects of the vertebral body  Secondary curvature:  Convex (ant): Cervical, Lumbar  Differential height of the anterior and posterior aspects of the intervertebral disc  Extreme curvatures Kyphosis Lordosis Scoliosis Definition Abnormal thoracic curvature Abnormal lumbar or cervical Abnormal lateral thoracic curvature with of the vertebral column curvature of vertebral column rotation of vertebrae Causes Result of erosion of the Weak trunk musculature Asymmetrical weakness of the intrinsic anterior part of the vertebrae Increase abdominal contents back muscles (myopathic scoliosis) which may lead to Line of gravity disrupted Failure of one half of the vertebrae to compression of the vertebral develop (hemivertebra) body Differences in length of the lower limbs Examples Osteoporotic males and Late stage of pregnancy Girls aged 12 to 15 years females Obese individuals  SCOLIOSIS  Idiopathic scoliosis  Congenital scoliosis:  Most common type  Present from birth  Little understanding  Maternal factors: alcohol, diabetes  Normal vertebral anatomy  Associated other developmental abnormalities  Never present at birth  Spinal malformations  Occur infantile, juvenile or  Genitourinary tract defects – 25% adolescent age groups  Cardiac defects – 10% Rotated vertebrae - adult Hemivertebra - infant VERTEBRAL LIGAMENTS…1 ANTERIOR LONGITUDINAL LIGAMENT:  Strong, broad fibrous band  Attached:  Antero-lateral surface of vertebral bodies  Interverbral discs from sacrum  Ant tubercleanterior arch of C1  Occiptal bone  Function:  Prevent hyperextension of vertebral column  (ALL other ligaments limit hyper flexion)  VERTEBRAL LIGAMENTS…2 POSTRIOR LONGITUDINAL LIGAMENT:  Narrower, weaker fibrous band  Extend from C2 to the sacrum  Within vertebral canal  Attached to intervertebral discs  Function:  Weakly resist hyperflexion  Helps prevent/redirect posterior herniation of nucleus pulposus  ACCESSORY LIGAMENTS  Ligamentum flavum  Attaches to internal surface of the laminae of adjacent vertebrae  Thicker as descend  Fx:  Helps preserve normal curvature  Limits abrupt vertebral column flexion  Assist with straightening column after flexion  ACCESSORY LIGAMENTS  Supraspinous ligament  Tips of spinous processes C7 to sacrum  Strong, fibrous  Apices of adjacent spinous processes  Merges with the nuchal ligament  Resists hyperflexion  Interspinous ligament  Root of spinous process to apex of neighboring vertebrae Root of spinous  Weak, ‘membranous’ process Apex of spinous process  ACCESSORY LIGAMENTS  Nuchal ligament  Base of the skull to cervical spinous processes  Above C7 to the external occipital protuberance  Function: Serves as muscle attachment site  Intertransverse ligament  Between adjacent transverse processes  Function: Limits lateral flexion