Spine Injury Daniel Ira Department of Trauma Suregry University Hospital Brno logo nAnatomy n ligaments-upper-cervical-spine nGoals in the Spine-Injured Patient nSave life nRestore and maintain spinal cord function preventing secondary injury nDecompress, realign and stabilise the spinal column nProgrammed rehabilitation nFollow ATLS protocol nIndex of suspicion for spinal injury – especially in coma patients and the drunk; particularly the C-spine is assumed injured and unstable until proven otherwise nDo no harm and good protection of the C-spine. Clinical and X-ray assessment – and check for deformity and step nBeware of problematic areas, e.g. cervicothoracic junction (CTJ) nMaintain perfusion and oxygenation nComplete examination nCervical X-ray Assessment n nLower part of C-spine = one vertebral width (retro-pharyngeal n space > 7 mm, or retro-tracheal space > 14 mm; displaced prevertebral stripe ± deviation of trachea should be noted) n nAlignment: look for any lordosis, acute kyphosis, torticollis, widened n interspace, axial rotation of the vertebrae n nAdult Atlas-Dens interval (ADI) > 4 mm abnormal (5 mm in children) n narrow/widened disc space, wide facet joint, and look for facet n dislocation – unilaterally, can check oblique view if unsure n nThe ATLS course teaches that the cervical spine lateral film done n as part of the trauma series is 75% sensitive. This means we will be missing 25% of injuries. n CervicalSpine_Fig01_en n CervicalSpine_Fig02_en_1 nCT: nOccult fracture (e.g. lateral masses) nDegree of retropulsion nDouble vertebra sign suggestive of fracture dislocation n3D reconstruction, as well as coronal/sagittal reconstructions n nMRI – advantages can assess: nDisc nCord (oedema, bleeding) nLigament (integrity) nHaematoma (e.g. epidural) n n n Common mechanism nCompression nFlexion nExtension nRotation nLateral bending nDistraction nPenetration n minerva philadelphia collar adams n Halo_T1 approaches DSCN0973 DSCN0973 DSCN0975 DSCN0907 DSCN0905 Posterior stabilization P1030611 P1030612 P1030613 P1030621 Anterior stabilization n P1030616 P1030614 P1030622 P1030629 P1030628 nFractured Occipital Condyle nMost result from direct blow in association with head injury nEasily missed on X-ray, may need CT for Dx nAnderson and Montesano Classification n Type 1: impacted fracture with comminution n Type 2: associated with fractured base of skull n Type 3: avulsion fracture of alar ligament attachment n Treatment n Types 1 and 2: stable, rigid collar halo n Type 3: unstable, needs halo immobilisation n n P1030560 P1030561 nOccipitocervical Instability/Dislocation nThe incidence of occiput–C1 is higher in children, since the lateral masses (articulating with the occipital condyles) are flatter. Important soft tissue supports in this region include: alar ligament, tectorial membrane, joint capsule and apical ligament. many are fatal n Treatment nAcute situation: halo traction contraindicated in type II. Then elective occipital-cervical fusion (mostly by occipito-cervical plating), beware of Cx like vertebral artery injury and that of cranialnerves n P1030562 P1030573 nFracture Atlas C1 nInjury mechanism: axial loading and frequently hyperextension nCanal is spacious here, neural deficit rare nLevine Classification of C1 Fractures nType 1: fractured posterior arch nType 2: fractured lateral mass nType 3: classic Jefferson’s burst fracture nTreatment nTypes 1 and 2: halo treatment, nType 3: operative fusion P1030576 n n Fractured Odontoid C2 n20% cervical spine injuries nMore in elderly from simple falls. In younger individuals, may result nfrom a blow to the head high speed accidents nPresent with suboccipital pain, neural deficit uncommon, but can nvary from neuralgia to quadriparesis n nAnderson and D’Alonzo Classification nType 1: Only the tip is fractured – essentially an avulsion injury of nthe apical and alar ligaments. Rule out distraction-type injury nType 2: Waist fracture – non-union risk increased in: smokers, n> 5 mm displacement, advanced nType 3: Base / Isthmus n nTreatment nType 1: orthosis adequate if no distraction injury nType 2: consider halo if undisplaced, displaced cases either anterior nodontoid screw (one or two screws), or posterior C1–C2 fusion nType 3: depending on the fracture personality, either Minerva or nhalo, seldom require surgery P1030566 P1030567 n P1030575 nTraumatic Spondylolisthesis of Axis (Hangman’s Fracture) nNormal stress on the pars is great because the axis acts as a transition vertebra between the upper and lower cervical spine nUsual mechanism: involves hyperextension, flexion usually element of axial loading. nTreatment nCollar, halo-vest for 12 weeks, surgery n (C2–C3 fusion, sometimes posterior C1–C3 fusion) P1030568 P1030569 P1030572 P1030571 P1030570 nC1–C2 Subluxation: DDx nCan be seen with ruptured transverse ligament, or rotatory subluxation nC1–C2 subluxation may also be associated with atlas or odontoid nfractures nRotatory Subluxation nMore often seen in children nClinically, the head is tilted towards the side of fixation, while the nchin is pointed in the opposite direction. Open-mouth X-ray view is nuseful nHawkins and Fielding Classification nType 1: rotational displacement only, no anterior translation nType 2: rotational displacement and anterior translation 3–5 mm nType 3: rotational displacement and anterior translation >5 mm nType 4: posterior translation and rotation P1030563 n P1030564 P1030565 nInjury to the Sub-axial Cervical Spine nNormal Structural Constraints nMost of the flexion/extension movements of the cervical spine occur at the most mobile segment, C3–C7, nResistance to hyperextension is offered by: anterior longitudinal ligament (ALL), annulus fibrosis, anterior two-thirds of the vertebra nResistance to hyperflexion is offered by: facets and capsule, ligamentum flavum, the supraspinous and interspinous ligament nCriteria for Cervical Spine Instability (Panjabi and White) nThis was based on biomechanical laboratory experiments on cadavers nThe following parameters are assessed and a score of ≥5 implies instability. nHowever, if the spine is obviously unstable (e.g. fracture ndislocation), no need for such calculations nAnterior element destroyed or cannot function: 2 points nPosterior element destroyed or cannot function: 2 points nSagittal plane translation > 3.5 mm: 2 points nSagittal plane rotation > 11: 2 points nPositive stretch test: 2 points nDamage to cord: 2 points nDamage to root: 1 point nAbnormal disc narrowing: 1 point nAnticipate dangerous loading: 1 point n nAllen’s Mechanistic Classification n nVertical compression n nCompressive flexion n nDistractive flexion n nLateral flexion n nCompressive extension n nDistractive extension n P1030577 n P1030579 P1030578 nVertical Compression n nMostly from diving injuries or car accidents n nTreatment n rigid cervical orthosis, halo immobilisation, operation especially if neural compromise by anterior decompression, grafting and anterior posterior instrumentation frequently added n nCompressive Flexion n n There are five stages in Allen’s classification, with increasing vertebral compression/comminution, and disruption of the posterior tension band. n nCaused by axial loading injuries as in diving and vehicle collisions n nTreatment n cervical orthosis, halo immobilisation anterior decompression, bone grafting and instrumentation. (Posterior stabilisation considered if significant disruption of the n posterior tension band) n n nLateral Flexion nStage 1: ipsilateral fracture of the centrum and posterior arch nStage 2: ipsilateral fracture of the vertebral body and contralateral nbone/ligament failure nMost of these injuries need traction reduction and surgical stabilisation n nCompressive Extension n nMost severe end of the spectrum involves fractured vertebral arch nand 100% anterior displacement of the vertebral body. Fracture dislocations n need combined anterior and posterior surgery n nDistractive Extension n nCharacterised by a spectrum of disruption of anterior constraints n(ALL and anterior annulus) to the posterior annulus and nposterior longitudinal ligament (PLL). May try halo, especially if nbony rather than ligamentous failure is involved. Operative fixation nusually involves plating and anterior reconstruction n P1030581 P1030584 P1030582 P1030581 n P1030583 nThoracolumbar Fractures nIt is commonly mentioned that most thoracolumbar injuries result from high energy trauma nWhile this is still true, be aware of the sharp rise in the incidence of wedge compression fractures in the elderly osteoporotic population. nThree Functional Regions nThoracic spine: stability enhanced by the rib cage, but has a narrow n canal and blood flow watershed near the mid-thoracic spinal cord. nHence, although thoracic fracture is less common than in the other n two regions, there is a higher chance of cord injury if fracture occurs. nThe cord:canal ratio is 40% for the thoracic spine, compared with n 25% in the C-spine nThoracolumbar junction: region of high stress as there is change in n sagittal profile and the spine transitions from the stiff thoracic region n to the mobile lumbar region; 50% of fractures occur in this region. nDepending on the location of the conus, neural injury can present n as upper or lower motor neuron pattern or mixed. The relative incidence n of thoracolumbar fractures according to Gertzbein: T1–T10 n 16%, T11–L1 52%, L1–L5 32% nLumbar spine: notice L3–L5 vertebrae lie below the pelvic brim with n added stability from the iliolumbar ligament. For this and other reasons, n the success rate of non-operative treatment of fractures in this n region is higher than at the TLJ. Neural deficit is seldom complete n because of wider spinal canal, and the cauda equina is more resistant n to compression than the cord. nClinical Assessment nAssess vital signs and general assessment nLocal spinal assessment of the acute trauma patient follows the ATLS nprotocol, remember to log roll the patient, check for palpable steps,etc. nAssess any neurological deficit and carry out per rectum examination nAssociated injuries (of the axial skeleton or otherwise) are common in those suffering from high energy trauma nRadiological Assessment nX-ray: assess overall coronal and sagittal alignment, soft tissue nshadows, namount of vertebral height loss and of translation or rotation. nCheck the posterior vertebral line or profile to detect any middle column involvement. X-ray of the entire spine in two views recommended in high energy trauma nCT: good to see bony details, e.g. useful in assessing the middle column in suspected burst fracture, assessing the degree of retropulsion, nMRI: good to assess ligamentous injuries, e.g. suspected ligamentous chance fractures; and for assessing spinal cord injuries nDenis Concept of Three Columns nAnterior column: include mainly the ALL, anterior vertebral body, nanterior annulus nMiddle column: includes mainly the PLL, the posterior vertebral nbody and posterior annulus nPosterior column: includes mainly the posterior capsuloligamentous complex, facet, pedicles dennis nWhat Constitutes Instability? nIt is clinically useful to consider instability being present nif: Marked neurological deficit (some spinal fractures or subluxations can spontaneously reduce after injury. If, during the moment of impact, the spine deforms sufficiently to cause significant injury to the neural elements, it is highly likely the spine is unstable) nRisk of deformity progression (radiologic clues include: >25ｰ kyphosis, n>50% vertebral height loss, >40% canal compromise) n≥ Two Denis’s columns disrupted, especially if the middle column is not intact nGoal of Treatment nCorrection or prevention of further deformity nRestoration of stability nNeural decompression if necessary nIf fusion anticipated, attempt to achieve stability with fusion of as few as possible motion segments nGeneral Approach nClassify the fracture nCan the fracture be treated conservatively? nIf operation required, what approach should we use? nWhat are the deforming forces, and how can we go about reducing nthe fracture? nWhat instrumentation is needed, if any? n n P1030600 P1030599 P1030597 P1030598 n Classifications nDenis Classification (an X-ray Classification) nMinor injuries: include fracture of transverse process, spinous process, pars, facet articulations, etc. nMajor injuries: nCompression fracture nBurst fracture nFlexion distraction injury nFracture dislocation n nMcAfee Classification (a CT Classification) nWedge compression fracture nStable burst fracture nUnstable burst fracture nChance fracture nFlexion distraction injury nTranslational injury n [USEMAP] AO classification n P1030642 P1030643 P1030644 nType A, vertebral body compression injury : nA1, vertebral body wedge impaction fracture nA2, split fracture nA3, comminuted fracture or burst fracture. n nType B, anterior and posterior element ninjuries with distraction : n B1, predominantly ligamentous n posterior flexion-distraction injury; n B2, predominantly osseous posterior n flexion-distraction injury; n B3, injury involving hyperextension and n shearing through the disc. n nType C, anterior and posterior element injuries with rotation : nC1, type A injury with rotation; nC2, type B injury with rotation; nC3, oblique fracture with rotational shear ao spine 1 aospine3 aospine 2 nConservative Versus Surgical Treatment nThe previously mentioned concept of instability is very useful here nMost thoracolumbar fractures can in fact be treated conservatively,especially if there is no significant deformity or neurological deficit nA recent study in a group of stable burst fracture patients without neural deficit revealed comparable clinical outcome with either conservative or operative treatment n jewwet somi-brace1 nAnterior, Posterior or Combined Approach nIndication for anterior approach: nSizable retropulsion fragments causing anterior compression. nDelayed situations when indirect reduction from posterior approach difficult (thoracolumbar approach for TLJ fractures, retroperitoneal approach for lumbar fractures) nIndication for posterior approach: chance fracture, flexion distraction injury, some unstable burst fractures nCombined approach: fracture dislocation cases, some ligamentous chance fractures approaches n DSCN0952 DSCN0945 DSCN0982 DSCN0986 n DSCN0968 DSCN0970 nSelection of Instrumentation nWhat Is the Preferred Posterior Lumbar Fixation? nMost posterior instrumentation nowadays uses segmental pedicle screw fixation since it has superior stability as it stabilises all three columns, spans fewer segments and is easier to restore an element of lordosis. If short segment of the spine is spanned, use of cross-links is recommended to confer torsional stability nInstruments for Anterior Fixation nCommonly used constructs for anterior instrumentation include: Plate-style systems, and rod-style systems,anterior fusion cages n P1030630 P1030631 n P1030635 P1030637 P1030639 P1030641 nMinor Fractures nMinor injuries include fracture of transverse process, spinous process, facet articulations, etc. nAccording to Denis, most of these are adequately treated by conservative means such as thoracolumbosacral orthosis (TLSO) nWedge Compression Fractures nMostly occur in osteoporotic elderly, especially females nMost can be treated conservatively, but a handful with failed conservative treatment may benefit from vertebroplasty or kyphoplasty,provided there is no contraindication 2 nVertebroplasty and Kyphoplasty nIntroduction: Osteoporotic Vertebral Fractures nVertebral fracture is the most common of the fragility fractures nIt is not without morbidity, which includes: nKyphosis and loss of proper sagittal alignment nPain nLoss of height nEffect on pulmonary function especially if the thoracic vertebrae are involved n nWhat is Vertebroplasty? nVertebroplasty is a surgical procedure in which bone cement is injected ninto a usually collapsed, compressed (osteoporotic) vertebral nbody nThe procedure was first described by French surgeons. The cement is ninjected at high pressure via an 11-gauge needle through the pedicles nunder screening by biplanar fluoroscopy n n nWhat is Kyphoplasty? nEssentially similar procedure to vertebroplasty nThe Kyphon Inc. company developed a “bone tamp” that can be n inserted through a cortical window via a trans-pedicular route or n through the body to attempt reduction of the compressed vertebra nReduction is not always straight-forward since conservative treatment n is administered for 4–6 weeks before such procedures are underataken, n and reduction may not be easy after 6 or more weeks. nMost successful cases can thus only effect partial reduction nIndications for Vertebroplasty and Kyphoplasty nFailed conservative management 4–6 weeks nClinical pain location corresponds with radiologic abnormalities nPathologies that can be so treated: nOsteoporotic vertebral collapse n nAdvantages of Vertebroplasty nReliable and quick pain relief (within hours) nImproved force transmission, Early mobilisation, Early hospital discharge n nComplications of Vertebroplasty nNeurological Cx: e.g. radiculopathy nCement extravasation into spinal canal nCement intravasation as pulmonary emboli and hypotension nAllergic reactions nFractured pedicle or rib reported nPneumothorax nSepsis nEpidural haematoma in patients with coagulopathy P1030589 nStable Burst Fractures nFeature: besides anterior column compressive failure, there is by definition involvement of the middle column nRadiologically, increased inter-pedicular distance is seen on the AP X-ray; look for a contour disruption of the posterior vertebral nline on the lateral X-ray. CT is useful in assessing burst fractures nUnstable Burst Fractures nFeature: besides compressive failure of the anterior and middle ncolumns, there is also tensile failure of the posterior column n nUnstable Fractures Without Neurological Deficit nBurst fractures are caused by flexion and axial loading forces, operative nreduction can be attained posteriorly with reduction and fixation nby extension and distraction nAccording to experts like Garfin, operative intervention should be nconsidered if: > 25 gr kyphosis, > 50% loss of vertebral height, > 40% ncanal compromise nSurgical Approach nPosterior instrumentation options include hook-rod systems pedicle nscrew systems nAnterior approach may be needed to retrieve sizable retropulsed nfragment or if there has been a delay for several days rendering indirect nreduction by posterior approach difficult. nneeds to be individualised n n n P1030596 nUnstable Fracture with Neurological Deficit nAnterior approach is logical if feasible to relieve the anterior source of neural compression, especially in the presence of a sizable retropulsed fragment, i.e. direct decompression nWhether to add on anterior instrumentation like AO Ventrofix depends on factors like quality of the graft obtained, number of segments that need surgery, and whether posterior surgery is planned for any concomitant posterior injury nIndirect Reduction and Posterior Surgery nIndirect reduction from the posterior approach is based on ligamentotaxis. nHowever, it must be noted that the efficacy of indirect reduction decreases after day 5. nFlexion Distraction Injuries nFeature: distraction injury of anterior and middle column, and tensile nfailure of the posterior column nThe centre of rotation falls posterior to the ALL sometimes, and in nsuch cases the anterior column will have compressive failure nLevel of injury can be either one or two spinal levels nInjury force can go through bone or ligaments nCalled a “bony chance fracture” if the injury force goes horizontally nthrough bone nCalled a “ ligamentous chance fracture” if the injury force goes horizontally nthrough ligaments nTwo-thirds of chance fractures are associated with abdominal injuries, naccording to Denis, and may require operative intervention n nPrinciples of Treatment nLigamentous chance fractures treated conservatively will usually fail, nalthough have been tried with some reported success in children. nLigamentous chance fractures in adults all require posterior surgery nfor stabilisation and frequently anterior surgery as well. Preoperative nMRI to check the disc status is advisable nNot all bony chance fractures require operation. Fractures with <15ｰ nkyphosis and no neural deficit have been treated with success by extension nCasting nThe rest of bony chance fractures require surgery. Most require posterior nsurgery (the injury had already done the dissection for us), but nnot infrequently anterior surgery may need to be added nTranslational Injuries nThis group includes fracture dislocation injuries nInvolve facet dislocation or subluxation, the direction of which depends on the direction of the external force. Possibilities include anterior, nposterior translations frequently with a rotational element nAll are treated surgically via a posterior approach usually with segmental pedicle screw fixation. Intraoperative reduction is necessary before pedicle screw application. nRemember to tackle the not infrequent finding of dural tear nDistraction of Extension Injury nRare nMore common in patients with ankylosing spondylitis nCaused by an extension force striking the lower back, can cause disruptionc to the anterior tension band (ALL and annulus). In severe cases the posterior elements can be injured as well nOperative treatment is indicated if the fracture is unstable nComplications nIatrogenic neural injury nSepsis nLoss of reduction nHardware problem and failure (e.g. when there is inadequate anterior support and the posterior instrumentation is subjected to cyclic loading) nFailure of healing of the bony fracture or the ligamentous injury n