Recognition and Recognition and Treatment of Cervical Treatment of Cervical Disorders in Baseball Disorders in Baseball
ProfessionalsProfessionals
Donald S. Corenman, M.D., D.C.Donald S. Corenman, M.D., D.C.
Steadman Clinic- Vail, ColoradoSteadman Clinic- Vail, Colorado
Neckandback.comNeckandback.com
General Spine Trauma EtiologyGeneral Spine Trauma Etiology
MVA 45%MVA 45%falls 20%falls 20%sports 15%sports 15%violence 15%violence 15%misc. 5%misc. 5%
Baseball has a very low Baseball has a very low percentage of traumatic spinal percentage of traumatic spinal injuries- so what disorders do injuries- so what disorders do
they develop?they develop?
Aggravation of Degenerative Disc Aggravation of Degenerative Disc DisordersDisorders
Annular TearsAnnular Tears Degenerative Disc Disease/ Isolated disc resorptionDegenerative Disc Disease/ Isolated disc resorption Facet DiseaseFacet Disease Herniated Nucleus Pulposis/ RadiculopathyHerniated Nucleus Pulposis/ Radiculopathy Stretch Radiculopathy/ PlexopathyStretch Radiculopathy/ Plexopathy Foraminal stenosis- radiculopathyForaminal stenosis- radiculopathy Cervical Stenosis/ MyelopathyCervical Stenosis/ Myelopathy Deconditioning/ abnormal biomechanicsDeconditioning/ abnormal biomechanics
Cervical SpineCervical Spine weight bearing 15-20 poundsweight bearing 15-20 pounds specialized vertebra (C1 and C2)specialized vertebra (C1 and C2) spinal cordspinal cord Lordosis from trapezoidal discsLordosis from trapezoidal discs thinner annulusthinner annulus Uncovertebral jointsUncovertebral joints Small neural foramenSmall neural foramen
Annular AnatomyAnnular Anatomy Annular fibers are in lamina Annular fibers are in lamina
(layers)(layers) Approximately 60 layers from Approximately 60 layers from
outside to innermostoutside to innermost When nucleus loses hydration When nucleus loses hydration
(aging)- pressure drops and more (aging)- pressure drops and more stress on annulusstress on annulus
Rotation stretches 50% of fibers Rotation stretches 50% of fibers (and relaxes the other 50%)(and relaxes the other 50%)
Disc loses 50% of strength by Disc loses 50% of strength by rotationrotation
Flexion loads disc and stretches Flexion loads disc and stretches fibers (possibly to failure)fibers (possibly to failure)
Circulatory Changes in the DiscCirculatory Changes in the Disc Notochord turns into nucleus of discNotochord turns into nucleus of disc Vascularity of disc diminishes – arterioles lose their access to the disc as the endplate Vascularity of disc diminishes – arterioles lose their access to the disc as the endplate
maturesmatures Disc becomes more avascular over time (largest mass of avascular tissue in the body)Disc becomes more avascular over time (largest mass of avascular tissue in the body) Imbibition- only nutrient exchange after this poinImbibition- only nutrient exchange after this pointt
Biochemical Changes to the Biochemical Changes to the Intervertebral DiscIntervertebral Disc
Imbibition- poor exchange of nutrientsImbibition- poor exchange of nutrients Lactate levels build and pH drops- especially in the Lactate levels build and pH drops- especially in the
center of the nucleuscenter of the nucleus Internal cell metabolism dropsInternal cell metabolism drops Hydrophyllic proteoglycans break down and are not Hydrophyllic proteoglycans break down and are not
replacedreplaced Pressure drops in nucleus as a resultPressure drops in nucleus as a result Increased stress on the annulusIncreased stress on the annulus Genetic history Genetic history
Mechanical Changes to the DiscMechanical Changes to the Disc Pressure drop from dissolution of Pressure drop from dissolution of
hydrophyllic proteoglycanshydrophyllic proteoglycans Aberrant motion to posterior Aberrant motion to posterior
annulusannulus Tears occur in annulus fibrosisTears occur in annulus fibrosis Disc height reduction imbricates Disc height reduction imbricates
facetsfacets Above causes disc to become less Above causes disc to become less
able to compensate for loadingable to compensate for loading
Discal Changes with AgingDiscal Changes with Aging After skeletal maturity, type I After skeletal maturity, type I
collagen increases and discal collagen increases and discal water decreases (stiffens disc)water decreases (stiffens disc)
O2 concentration is 20-30X O2 concentration is 20-30X greater at periphery of disc than greater at periphery of disc than at center (imbibition)at center (imbibition)
Chondrocyte cells decrease and Chondrocyte cells decrease and necrotic cells can be identifiednecrotic cells can be identified
Entire disc appears disorganizedEntire disc appears disorganized Large voids appear (vacuum Large voids appear (vacuum
sign)sign) Peripherally- osteophyte Peripherally- osteophyte
formation (enthesopathy)formation (enthesopathy)
Degenerative CascadeDegenerative Cascade Disc loses hydrationDisc loses hydration Disc walls subjected to Disc walls subjected to
shear and torsionshear and torsion Annulus disintegratesAnnulus disintegrates Bone now absorbs Bone now absorbs
shockshock ““Microfractures”Microfractures” ““Patient Wiring”Patient Wiring”
EnthesopathyEnthesopathy Sharpy’s fibers connect Sharpy’s fibers connect
annulus to boneannulus to bone When these undergo traction When these undergo traction
by aberrant motion, by aberrant motion, periosteum is also pulled offperiosteum is also pulled off
New bone formation occurs New bone formation occurs at junction of periosteum, at junction of periosteum, bone and Sharpy’s fibersbone and Sharpy’s fibers
Most common cause of Most common cause of foramenal stenosis and foramenal stenosis and cervical radiculopathy cervical radiculopathy
Pain OriginationPain Origination
Why do we need pain receptors Why do we need pain receptors in the first place?in the first place?
Nociceptors are important Nociceptors are important to signal damaging motion to signal damaging motion to the disc and bone of the to the disc and bone of the vertebravertebra
Without this feedback of Without this feedback of noxious stimulus, a noxious stimulus, a CharcotCharcot spine develops spine develops
Destruction occurs in any Destruction occurs in any joint that has no feedback joint that has no feedback mechanism by overload mechanism by overload and motion beyond tissue and motion beyond tissue tolerancetolerance
Smyth and Wright, JBJS(B) 40ASmyth and Wright, JBJS(B) 40Aintraoperative connection of nylon threads to intraoperative connection of nylon threads to
spinal structures with post-operative stimulation spinal structures with post-operative stimulation
•Tension on normal nerve root produced no sciaticaTension on normal nerve root produced no sciatica•Interspinous ligament and Ligamentum Flavum Interspinous ligament and Ligamentum Flavum produced no painproduced no pain•Dura Mater was generally insensitiveDura Mater was generally insensitive•The greater the pressure to a compromised nerve The greater the pressure to a compromised nerve root, the greater the length of radiated pain root, the greater the length of radiated pain
Kuslich, OCNA April 91Kuslich, OCNA April 91pain response to tissue stimulation under local pain response to tissue stimulation under local
anesthesiaanesthesia
•Capsule- rarely generated any pain upon Capsule- rarely generated any pain upon stimulation. (Lumbar normal facets)stimulation. (Lumbar normal facets)•Muscle could produce sharp pain with forceful Muscle could produce sharp pain with forceful stretching “but only rarely simulated the deep dull stretching “but only rarely simulated the deep dull ache of lumbago”ache of lumbago”•““Normal Nerve Root”- completely insensitive to Normal Nerve Root”- completely insensitive to pain, forceful prolonged retraction caused mild pain, forceful prolonged retraction caused mild paresthesias onlyparesthesias only
Kuslich, OCNA April 91Kuslich, OCNA April 91pain response to tissue stimulation under local pain response to tissue stimulation under local
anesthesiaanesthesia
•Sciatica- only by stimulation of swollen or Sciatica- only by stimulation of swollen or stretched nerve rootsstretched nerve roots•Back Pain- stimulation of outer layer of Back Pain- stimulation of outer layer of posterior annulus and PLLposterior annulus and PLL•Buttocks Pain- simultaneous stimulation of Buttocks Pain- simultaneous stimulation of annulus and nerve rootannulus and nerve root
Cortical Pain IdentificationCortical Pain Identification Homunculus of Homunculus of
cerebral cortex cerebral cortex dedicated to only dedicated to only certain number of certain number of receptors in each areareceptors in each area
Neck and lower back Neck and lower back have minimal number have minimal number of receptors compared of receptors compared to other regional areas to other regional areas of coverageof coverage
Referral PainReferral Pain Cloward, Dwyer, BogdukCloward, Dwyer, Bogduk Thought to be generated in the cord from strong impulses that spread from Thought to be generated in the cord from strong impulses that spread from
internuncial neuronsinternuncial neurons Associated with somite originAssociated with somite origin Sympathetic afferents?Sympathetic afferents?
Physical Examination Physical Examination
Sensory EvaluationSensory Evaluation C1- no rootC1- no root C2-3- greater/lesser occipital nerveC2-3- greater/lesser occipital nerve C4- posterior neck and anterior chest C4- posterior neck and anterior chest
(cervical angina)(cervical angina) C5- deltoid (lat shoulder)C5- deltoid (lat shoulder) C6- thumbC6- thumb C7- long fingerC7- long finger C8- little fingerC8- little finger T1-ulnar forearm/armT1-ulnar forearm/arm
Motor InnervationMotor Innervation C3- No motor (ansa cervicalis) C3- No motor (ansa cervicalis) C4- No motor (ansa cervicalis)C4- No motor (ansa cervicalis) C5- deltoidC5- deltoid C6- biceps, supinator, wrist extensorsC6- biceps, supinator, wrist extensors C7- triceps, wrist flexors, MCP extensorsC7- triceps, wrist flexors, MCP extensors C8- grip (poorest recovery)C8- grip (poorest recovery) T1- intrinsics (finger abductors)T1- intrinsics (finger abductors)
Myelopathic SymptomsMyelopathic Symptoms Lhermitte’s signLhermitte’s sign Myelopathy handMyelopathy hand ParesthesiasParesthesias Incoordination of gaitIncoordination of gait Bowel and bladderBowel and bladder Pain in nonradicular Pain in nonradicular
distributiondistribution
Myelopathy SignsMyelopathy Signs HyperreflexiaHyperreflexia ClonusClonus Inverted radial reflexInverted radial reflex Hoffman’s signHoffman’s sign L’hermittes signL’hermittes sign Psoas WeaknessPsoas Weakness Myelopathy handMyelopathy hand
Myelopathy- Spinal Canal Myelopathy- Spinal Canal MeasurementsMeasurements
Critical Diameter- Critical Diameter- 13mm (Veidlinger)13mm (Veidlinger)
Torg RatioTorg Ratio Kinetic Aspects of Kinetic Aspects of
compressioncompression
Central Cord SyndromeCentral Cord Syndrome The most common and The most common and
most missedmost missed of all cord of all cord injuriesinjuries
Hallmark is temporary Hallmark is temporary paralysis that normally paralysis that normally disappears from 2min to 2 disappears from 2min to 2 hourshours
Burning of dorsum of Burning of dorsum of handshands
Arm greater than leg Arm greater than leg symptomssymptoms
Immobilize and transport!Immobilize and transport!
Cervical HNPCervical HNP Neck, arm and posterior Neck, arm and posterior
scapularscapular pain pain Greater the compression, Greater the compression,
pain radiates further down pain radiates further down the armthe arm
Motor, sensory, reflex, cord Motor, sensory, reflex, cord signssigns
Better with neck flexion, arm Better with neck flexion, arm external rotation/ abduction external rotation/ abduction (Bakody’s sign)(Bakody’s sign)
Selective Motor Root CompressionSelective Motor Root Compression
Selective compression of motor Selective compression of motor rootroot
PainlessPainless Anterior/ posterior roots don’t Anterior/ posterior roots don’t
join until almost past DRGjoin until almost past DRG Anterior root is motor branchAnterior root is motor branch
Selective Motor Root CompressionSelective Motor Root Compression
Facet BlocksFacet Blocks
Facets considered as 40% of axial pain Facets considered as 40% of axial pain generators (Bogduk)generators (Bogduk)
Referral pain patterns mimic headaches, Referral pain patterns mimic headaches, shoulder pain and thoracic painshoulder pain and thoracic pain
MRI and CT normally negative (non-MRI and CT normally negative (non-diagnostic)diagnostic)
Motion palpation is valuable diagnostic Motion palpation is valuable diagnostic screenscreen
Only diagnostic tool is facet blockOnly diagnostic tool is facet block Capsular injections vs. medial branch Capsular injections vs. medial branch
blocksblocks
Surgical IndicationsSurgical Indications Always conservative treatment unless Always conservative treatment unless
significant motor deficit, myelopathy or significant motor deficit, myelopathy or severe painsevere pain
Motor deficitMotor deficit MyelopathyMyelopathy Severe painSevere pain InstabilityInstability ? Quicker functional recovery?? Quicker functional recovery?
ACDFACDF One level is a “home run” operation with greater than a 95% One level is a “home run” operation with greater than a 95%
success ratesuccess rate Back to full active participation in 8 weeksBack to full active participation in 8 weeks More than two levels associated with junctional breakdown in More than two levels associated with junctional breakdown in
higher level sportshigher level sports
Decompressing CanalDecompressing Canal
Post Op ACDFPost Op ACDF
Successful Artificial Disc Successful Artificial Disc CharacteristicsCharacteristics
Disc must recreate the Disc must recreate the biomechanics of the original biomechanics of the original discdisc
Facet joints must be normal Facet joints must be normal and not overloadedand not overloaded
Wear characteristics long termWear characteristics long term Shock absorptionShock absorption Ability to revise easilyAbility to revise easily Low failure rateLow failure rate Appropriate indicationsAppropriate indications
Artificial Disc ProblemsArtificial Disc Problems Total knee or hip- 10-15 year Total knee or hip- 10-15 year
life expectancylife expectancy Current discs don’t have shock Current discs don’t have shock
absorption capabilityabsorption capability Cervical discs may have too Cervical discs may have too
much freedom of motion- much freedom of motion- overload facetsoverload facets
Failure associated with wear Failure associated with wear debris- granulomas, bone loss, debris- granulomas, bone loss, adhesions to local structuresadhesions to local structures
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