The Spine Macaire Grobe, Katherine Callahan, Sophia Powell, Bin Chen, and Theo DiPauli

Evolution of the Human Spine The structure of the spine has changed significantly over the course of millions of years of evolution. Notochords in the first vertebrae The development of the spinal cord Transition for humans to walk upright http://factsanddetails.com/world/cat56/sub360/item1492.html

Walking Upright Bone and Joint Adaptions: Spine Adaptions: Ability to lock our legs Inward thigh bones Arched foot Gluteal Abductor Spine Adaptions: Curved structure of the spine Foramen Magnum http://humanorigins.si.edu/human-characteristics/walking

Embryonic Development Spine starts to form during 4th week of embryonic development Notochord: Sclerotome have loosely and densely packed cells. Notochord expands to form the nucleus pulposus, which is later surrounded by circular fibers of the annulus fibrosis. Neural Tube: Mesenchymal cells here forms the vertebral arch. Body Wall: Mesenchymal Cells form the costal processes which develop into ribs in the thoracic region. Chondrification: The centers in the vertebral arches fuse with each other and the centrum The spinous and transverse processes develop from extensions of chondrification centers in the vertebral arch http://phys.org/news/2011-02-fetal-surgery-kids-spine-defect.html

Embryonic Development Mesenchymal cells from the sclerotome of the somites start to form in three main areas: notochord, neural tube, and body wall In the 6th week, chondrification occurs http://imueos.wordpress.com/2010/09/26/development-of-musculoskeletal-system/

Curvature of the Spine Primary Curve: shaped like a C Secondary Curve: Cervical Spine develops Final Curve: lumbar spine develops http://blog.intellidance.ca/blog/2-15-2011/c-s-how-nurture-your-babys-spine-development http://www.emory.edu/ANATOMY/AnatomyManual/back.html

Biomechanics of Spinal Injuries The spine shares a similar structure to a flexible segmented column. Offers strong support Prone to various kinds of injuries Fractures of the spine can be classified by: Causal Movement Location Shape Severity http://www.bluechipspine.com/first-visit

Classifications of Fractures: Three Column Concept Major and Minor Fractures http://www.doctorschierling.com/whiplash-type-injuries.html Stable vs. Unstable http://radiopaedia.org/articles/thoracolumbar-spinal-fractures-mcafee-classification-1 Specific Fracture Types: http://www.virtualmedstudent.com/links/musculoskeletal/three_column_spine_model_overview.html Compression Flexion Burst Dislocation Three Column Concept Major and Minor Fractures

Classifications of Fractures: Stable vs. Unstable Specific Fracture Types

Spinal Cord Injury: What is spinal cord injury? Why is it significant? A spinal cord injury occurs when there is damage to the spinal cord either from trauma, loss of its normal blood supply, or compression from tumor or infection. Why is it significant? The spinal cord is incapable of healing itself. Complete spinal cord injury: cannot send signals below the level of injury. Incomplete spinal cord injury: some movement and sensation below the injury.

Spinal Cord Injury: Causes: The most common cause of spinal cord injury is trauma. Types of trauma include: falls from heights, violence (stabbing or gunshot wounds to the spine), or sporting injuries (diving, football, rugby, equestrian, etc.) Spinal cord injury can also be caused by compression of the cord by a tumor, infection, or inflammation. Spinal stenosis Types of trauma include: falls from heights, violence (stabbing or gunshot wounds to the spine), or sporting injuries (diving, football, rugby, equestrian, etc.)

Conditions that affect the spinal cord: Tumors Infections such as meningitis and polio Inflammatory diseases Autoimmune diseases Degenerative diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy

Diseases of the Spinal Cord: Meningitis Polio Amyotrophic lateral sclerosis (ALS) Spinal muscular atrophy (SMA)

Spine Treatment Level 1: Mobilization and Physical Therapy Level 2: Immobilization, Braces Level 3: Spinal Surgery; Fusion, Disk Implants

Level 1: Mobilization and Physical Therapy Two components: Passive physical therapy (heat/ice packs, ultrasound) Active Exercises (stretching) Manual physical therapy: Restore mobility Reduce muscle tension

Level 2: Immobilization, Braces Spinal bracing used for treatment of: low back pain trauma infections muscle weakness neck conditions osteoporosis

Cervical Braces Soft and hard collars Philadelphia collar Sterno-occipital-mandibular immobilization device (SOMI) Halo

Back Braces Two types of back braces commonly used: Rigid braces Corset (elastic braces)

Level 3: Spinal Surgery; Fusion, Disk Implants Spinal Fusion Artificial Disk Replacement (ADR)

Fusion Involves forming direct connection between vertebrae surrounding the painful disc(s) Pain relief occurs by stopping the motion of the painful disc(s).

Fusion http://www.spine-health.com/video/interbody-spine-fusion-surgery-video

Artificial Disk Replacement (ADR) Alternative to spinal fusion replaces damaged or worn out spinal disc with an artificial disc The Charité artificial disc is made of two metallic endplates and a plastic center

Artificial Disk Replacement (ADR) http://www.spine-health.com/video/total-disc-replacement-back-surgery-video

Christopher Reeve In 1995, famous actor Christopher Reeve broke his neck in a horseback riding incident. Paralyzed from neck down and unable to breathe

Background on the injury Second vertebrate (C2) causes instant death if displaced laterally by 5mm Fracture in any cervical vertebrate causes quadriplegia Spinal cord injuries breaks nerve fibers Destroys possible muscle movement in distal direction

Survived instant death Survived 60-70% chance mortality rate over the following week No recovery within 48 hours usually means no recovery

Spinal Cord Concussion Cervical Cord neurapraxia (CNN) Nerrowing of the spinal canal (stenosis) Torg or Pavlov ratios: Ratio of canal diamter to vertebral body 0.8< indicates significant for athletic Instantaneous loss of function of limbs but followed with complet recovery Most commonly occurs at the cervical vertabrates

Torg. J. et al, 1997

Both techniques share the same level of reoccurrence Torg. J. et al, 1997

How does it happen? Hyperextension, hyperflexion, axial load mechanisms on neck Spear tackle Occur in 7 out of 10,000 players per year (1.8 million people) and rising http://www.youtube.com/watch?v=UpdrHe31J-8

Why the rise? Helmets are too safe!

Long term effects Symptoms subside usually after 24 hours 56% chance of reoccurrence Repeat episode is directly proportional to diameter of player’s cervical spine canal If neurologic symptoms persist  surgery Second episode  termination of sport

Torg. J. et al, 1997

Case compilation of different CNN outcomes of athletes

Case Study Example 20 year old college defensive back 5 minutes of transient paralysis C-3, 5 narrowing of 0.66 C-4 narrowing of 0.62 Minimal anterior subluxation Returned to play after recovery

Minimal Flexion

… Fourteen months later Contact is made with head Classic spear tackle Axial load Fracture in the C4-C6 vertebrate

*Unilateral facet dislocation at C4-5 (C4 displaced anteriorly 25%) in sagittal plane *Oblique fracture *Three-part-two-plane fracture with small anterior fracture fragment *Non-displaced sagittal fracture through the vertebral body and partial fracture of the right lamina

Help efforts Christopher and Dana Reeve Paralysis Resource Center Located in New Jersey Funds for research, treatments/cures, for CNS disorders Advocate improvement of quality of life post-injury 22M to neuroscientist research http://www.reevebigidea.org

References [1] http://www.socalpaincenter.com/evolution-of-the-human-spine/ [2] http://www.pbs.org/wgbh/evolution/library/07/1/l_071_02.html [3] http://web.indstate.edu/thcme/duong/EMBRYOL.html#anchor59130 [4] http://blog.intellidance.ca/blog/2-15-2011/c-s-how-nurture-your-babys-spine-development [5] http://www.mayfieldclinic.com/PE-AnatSpine.htm#.VDXLLildW2o [6] http://imueos.wordpress.com/2010/09/26/development-of-musculoskeletal-system/ http://www.allaboutbackandneckpain.com/researchingtreatmentrecovery/braces.asp http://www.spineuniverse.com/treatments/bracing/neck-braces-type-spinal-brace http://www.spineuniverse.com/treatments/bracing/spinal-bracing http://www.ossur.com/injury-solutions/products/spine/spinal-traction/resolve-halo http://www.spine-health.com/conditions/scoliosis/back-braces http://www.cocwindsor.com/tlso http://www.spinesurgery.com/non-surgical-treatments/lumbar-bracing http://www.spine-health.com/treatment/artificial-disc-replacement/all-about-charite-artificial-disc-now-approved-use-us http://www.washingtonpost.com/wp-dyn/articles/A99660-1995Jun1.html http://www.uscspine.com/conditions/sports-injuries.cfm http://www.spineuniverse.com/conditions/spinal-fractures/types-spinal-fractures