Thoraco lumbar injuries

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Transcript of Thoraco lumbar injuries

Thoraco lumbar Thoraco lumbar injuriesinjuries

Thoraco lumbar Thoraco lumbar injuriesinjuries

Dr.Zameer AliDr.Zameer Ali

PG orthopaedicsPG orthopaedics

St stephens hospitalSt stephens hospital

• Cervical - 7 vertebrae• Thoracic - 12 vertebrae• Lumbar - 5 vertebrae• Sacral - 5 fused

vertebrae• Coccyx - 4 fused

vertebrae

Some important facts• Spinal cord ends below lower border of L1• Cauda equina is below L1• Mid dorsal spinal cord & neural canal space are of same

diameter hence prone for complete lesion

• Mechanical injury - early ischaemia, cord edema - cord necrosis

• Neurological recovery unpredictable in cauda equina ie. peripheral nerves

Thoraco lumbar injuries• Fractures and dislocations of the

spine are serious injuries that most commonly occur in young people. Nearly 43% of patients with spinal cord injuries sustain multiple injuries.

• Kraus et al. estimated that each year 50 people in 1 million sustain a spinal cord injury

• Of those who die within 1 year of their accidents, 90% die en route to the hospital.

• Overall, 85% of patients with a spinal cord injury who survive the first 24 hours are still alive 10 years later compared with 98% of patients of similar age and sex without spinal cord injury.

cause common of death

• According to the National Spinal Cord Injury Association, the most cause common of death is respiratory failure whereas in the past it was renal failure.

• An increasing number of people with spinal cord injury are dying of unrelated causes, such as cancer or cardiovascular disease, similar to that of the general population.

• Mortality rates are significantly higher during the first year after injury than during subsequent years.

history• A detailed history of the

mechanism of injury is important but frequently is unobtainable at the initial examination.

Statistics • prevalence 10 - 15 per million• age group 18 - 35 years • male/female - 3:1• RTA 51% - cars • Domestic 16%• Industrial 11%• Sports 16% - diving incidents• Self harm 5%

most common causes

• The most common causes of severe spinal trauma are

• motor vehicle accidents,• falls,• diving accidents, • gunshot wounds

type• Cervical 40%

• Thoracic 10%

• Lumbar 3%

• Dorso lumbar 35%

• Any 14%

Delay in diagnosis

• The most common causes of misdiagnosis were head trauma, acute alcoholic intoxication, and multiple injuries. Patients with decreased levels of consciousness or comatose patients often do not complain of back pain.

Delay in diagnosis• Profuse bleeding from severe

facial or scalp lacerations may divert attention from the cervical spinal injury

• Most isolated thoracic and lumbar spine fractures are related to osteoporosis and involve minimal or no trauma. In fact, osteoporosis-related fractures far outnumber trauma-related thoracic and lumbar fractures. Osteoporosis leads to approximately 750,000 vertebral fractures each year in the United States

• The annual rate of trauma-related thoracic and lumbar fractures is approximately 15,000 (14). Thoracic and lumbar fractures account for 30% to 50% of all spinal injuries in trauma patients

• In trauma patients, thoracic and lumbar fractures are concentrated at the thoracolumbar junction, with 60% of thoracic and lumbar fractures occurring between the T11 and L2 vertebral levels (15

• Neurologic injury occurs in one fourth of thoracic and lumbar fractures associated with trauma

Spinal instability

• A spine injury is considered unstable if normal physiological loads cause further neurological damage ,chronic pain and unacceptable deformity

Stability and Instability of the Vertebral

Column• The concept of spinal stability is

central to the field of spine surgery.

• Spinal fusion and fixation surgery, in fact, is performed primarily to restore stability of the spinal column after instability from injury, degeneration, or decompression to address neural tissue

• Spinal instability is variably defined, widely interpreted, and inconsistently measured

Treatment and outcome of spine injuries are integrally related to the neurological status,

definition of spinal stability in trauma should be centred on preservation of neural function.

• Historically, discussions of spinal stability have focused on the vertebral column and not on neural structures or neural function

Functional spinal unit composed of two adjacent

vertebrae and their intervening ligaments and inter vertebral disc,

• the anterior structures are the vertebral body and the intervertebral disc, and the posterior structures are the facet joints, laminae, spinous processes, and posterior intervertebral ligaments.

functional spinal unit is stable if all anterior structures plus one posterior structure are intact, or alternatively, if all posterior structures and one anterior structure are intact

White and panjabi • For assessing spinal instability• Thoraco lumbar stability usually

follows the middle column if it is intact then injury is usually stable

Thoracic and lumbar spine stability score element /point

score• Ant. element unable to function….2• Post elem. Unable to function ….2• Disruption of costovertebral

articulation …1• Radiographic criteria 4• Saggital displacement >2.5mm (2

points)

• Relative sagittal plane angulation >5 degrees…..2 points

• Spinal cord or cauda equina damage…2 pts

• Dangerous loading anticipated …1 pt

• Instability if score greater than 5

Lumbar spine stability scale

• Ant. element unable to function….2• Post elem. Unable to function ….2• Radiographic criteria 4 pts• Flex. /ext. x rays• Saggital plane translation >4.5 mm

or 15% 2 pts

• Sagittal plane rotation 2 pts• >15 degrees at L1 –L4 • >20 degrees at L4 – L5• >25 degrees at L5-S10r Resting x rays

• Sagittal plane displacement >4.5 mm or 15% 2 pts

• Relative sagittal plane angulation >22 degrees 2 pts

• Spinal cord or cauda equina damage 2 pts• Cauda equina damage 3 pts• Dangerous loading anticipated 1 pt

• Roughly three types of spinal instability are recognized

• First degree mechanical instability potential for late kyphosis

• E.g. severe compression fractures • Seat belt type injuries

• Second degree (neurologic instability)

• Potential for late neurologic injury • E.g. burst fractures without

neurological deficits

• Third degree (mech.and neur. Instability)

• E.g. fracture dislocations/severe burst fractures with neurologic deficit

McAfee• Factors indicative of instability in

burst fractures• >50% canal compromise• >15 to 25 degrees of kyphosis• >40 % loss of anterior vert.body

height

MULTIPLE SPINAL FRACTURES

• If a spinal fracture is identified at any level, the entire spine should be examined with anteroposterior and lateral views to document the presence or absence of spinal fractures at other levels.

• Multiple-level spinal fractures, which may be contiguous or separated, are estimated to occur in 3% to 5% of patients with spinal fractures

• Multiple noncontiguous spinal fractures rarely occur without injury to the spinal cord.

• Denis developed a three-column concept of spinal injury using a series of more than 400 CT scans of thoracolumbar injuries

Assesment of spinal stability

3 structural elements to be considered Posterior coloumn Middle coloumn Anterior coloumn

All fractures involving middle coloumn and at lest one other coloumn should be regarded as unstable.

• The anterior column contains the anterior longitudinal ligament, the anterior half of the vertebral body, and the anterior portion of the annulus fibrosus.

• The middle column consists of the posterior longitudinal ligament, the posterior half of the vertebral body, and the posterior aspect of the annulus fibrosus.

• The posterior column includes the neural arch, the ligamentum flavum, the facet capsules, and the interspinous ligaments

Denis classification• Minor spinal injuries• 1 Articular processe fracture (1%)• 2 transverse process fracture

(14%)• 3 Spinous process fracture (2%)• 4 Pars interarticularis fracture(1%)

Major spinal fractures

• Compression fractures 48%• Burst fracture 14 %• Fracture dislocation 16 %• Seat belt type factures 5 %

Compression fracture• 4 subtypes on basis of end plate

involvement• A fracture of both end plates 16%• B Fracture of superior end plate

62%• C fracture of inferior end plate 6 %• 4 both end plates intact 15%

Compression Fracture• Failure of anterior column

• Stable: – Tlso, hyperextension bracing

• Unstable (>50% height, >30% kyphosis, multi level)

– Progressive deformity

Burst Fracture

• Failure of anterior and middle column– Axial compression

• +/- failure of posterior column– Compression or tensile force

• Most common at T/L junction

Burst fracture subtypes• 4 subtypes on basis of end plate

involvement• A fracture of both end plates 24%• B Fracture of superior end plate 49%• C fracture of inferior end plate 7 %• 4 both end plates intact 15%• Burst lateral flexion 5 %

• Early stabilization is required in both saggital and coronal plane in patients with

• 1 neurological deficit• 2 Loss of vertebral body height >50 %• 3 angulations of >20 degree• 4 Canal compromise of >50 %

scoliosis of >10 degree

Burst Fracture• Neuro intact

– <20-30 kyphosis, <45-50 canal compromise

– >20-30 kyphosis, >45-50 canal compromise

• Neuro compromised

Flexion Distraction Injury

Chance fracture ,seat belt type fracture

• Bone or soft tissue?

Flexion Distraction Injury

• Type A one level bony injury• Type B one level ligamnetous injury• Type C two level injury through

bony middle column• Type D two level injury through

ligamentous middle column

Spinal Stability• Holdsworth 1963

• 2 column theory

• Post. ligaments

Spinal Stability• Denis 1983

• CT Scan

• 3 column theory

Pathophysiology of spinal injuries

• Stable and unstable injuries- Stable-vertebral components will not be

displaced by normal movements.

Unstable-Significant risk of displacements and consequent damage to

neural tissues

Spinal Stability

• Categorized major spinal injury into 4 groups:

– 1. Compression Fracture– 2. Burst Fractures– 3. Flexion Distraction Injuries– 4. Fracture Dislocations

• McAfee et al. determined the mechanisms of failure of the middle osteoligamentous complex and developed a new system based on these mechanisms

• Wedge compression fractures cause isolated failure of the anterior column and result from forward flexion. They rarely are associated with neurological deficit except when multiple adjacent vertebral levels are affected

• stable burst fractures the anterior and middle columns fail because of a compressive load, with no loss of integrity of the posterior elements

unstable burst fractures the anterior and middle columns fail in compression, and the posterior column is disrupted. The posterior column can fail in compression, lateral flexion, or rotation.

• Chance fractures are horizontal avulsion injuries of the vertebral bodies caused by flexion about an axis anterior to the anterior longitudinal ligament. The entire vertebra is pulled apart by a strong tensile force.

• flexion distraction injuries the flexion axis is posterior to the anterior longitudinal ligament. The anterior column fails in compression while the middle and posterior columns fail in tension. This injury is unstable because the ligamentum flavum, interspinous ligaments, and supraspinous ligaments usually are disrupted

• Translational injuries are characterized by malalignment of the neural canal, which has been totally disrupted. Usually all three columns have failed in shear

• Kelly and Whitesides described the thoracolumbar spine as consisting of two weight-bearing columns: the hollow column of the spinal canal and the solid column of the vertebral bodies.

Classification of Spinal Cord injury

• Many Grading Systems– Impairment Based

• Frankel• ASIA• Yale• Motor Index

Type of bony injury• Flexion

• Extension

• Flexion with rotation

• Compression

• The spine should be protected during this initial assessment

Lumbar and Sacral Motor Root Function

• The presence of an incomplete or complete spinal cord injury must be determined and documented by neurological examination

• Important dermatome landmarks are the nipple line (T4),

• xiphoid process (T7),• umbilicus (T10), and inguinal

region (T12, L1), as well as the perineum and perianal region (S2, S3, and S4).

Complete /complete spinal cord injury

• . Evidence of sacral sensory sparing can establish the diagnosis of an incomplete spinal cord injury

• If voluntary contraction of the sacrally innervated muscles is present, then the prognosis for recovery of motor function is good

• Some lumbar spine injuries may present as isolated root injuries with weakness of the foot or leg, depending on the specific root involved

spinal shock rarely lasts longer than 24 hours, it may last for days or weeks. A positive bulbocavernosus reflex or return of the anal wink reflex indicates the end of spinal shock.

.

Bulbocavernous reflex

Anal wink reflex

• If no motor or sensory function below the level of injury can be documented when spinal shock ends, a complete spinal cord injury is present and the prognosis is poor for recovery of distal motor or sensory function

Signs in an Unconscious patients

• Diaphragmatic breathing• Neurological shock (Low BP & HR)• Spinal shock - Flaccid areflexia• Flexed upper limbs (loss of extensor

innervations below C5)• Responds to pain above the clavicle only• Priapism – may be incomplete.

Signs of spinal injury• Forehead wounds – think of hyperextension injury

• Localized bruise

• Deformities of spine - Gibbus, feel a step & Priapism

• Beevors sign – tensing the abdomen umbilicus moves upwards in D10 lesions

Evaluation

• Radiographic Evaluation– Plain Xray– CT– MRI

• Mylography

• Spinal Stability

• Classification of Fractures

• Treatment of Specific Injuries

Imaging evaluation • X- rays • CT scan• MRI• myelography• CT scan significantly outperforms plain

radiography however it should not replace plain radiography as a screening test for evaluation of spinal injury

Radiographic Evaluation

• MRI– Indicated in all cases of neuro deficit?– Both intrinsic and extrinsic cord

injuries

• Mylogram– Replaced by MRI

SCIWORA• Spinal cord injuries without

roentgenographic abnormalities (SCIWORA) have been reported by Dickmen et al. to occur predominantly in children.

• Spinal cord injuries in children frequently occur without fracture-dislocation. Because of the inherent elasticity of the juvenile spine, the spinal cord is vulnerable to injury even though the vertebral column is not disrupted.

• SCIWORA is most common in children younger than 8 years of age. The recovery of neurological function depends on the patient's neurological status at presentation.

• Patients with incomplete injuries tend to recover, and those with complete injuries have a poor prognosis for recovery of neurological function

Pathophysiology• Primary Neurological damage Direct trauma, haematoma & SCIWORA < 8yrs old In 4hrs - Infarction of white matter occurs In 8hrs - Infarction of grey matter and irreversible paralysis

• Secondary damage Hypoxia Hypoperfusion Neurogenic shock Spinal shock

Grading of Spinal Cord Injury

GENERALISATIONS• (1) the greater the sparing of motor and

sensory functions distal to the injury, the greater the expected recovery;

• (2) the more rapid the recovery, the greater the amount of recovery; and

• (3) when new recovery ceases and a plateau is reached, no further recovery can be expected

• By definition, an incomplete spinal cord injury is one in which some motor or sensory function is spared distal to the cord injury.

• Complete - flaccid paralysis + total loss of sensory & motor functions

• Incomplete - mixed loss - Anterior sc syndrome - Posterior sc syndrome - Central cord syndrome - Brown sequard’s syndrome - Cauda equina syndrome

• An incomplete spinal cord syndrome may be a Brown-Séquard syndrome,

• central cord syndrome, • anterior cord syndrome,• posterior cord syndrome, or rarely monoparesis of the

upper extremity. Ninety percent of incomplete lesions produce either a central cord syndrome, a Brown-Séquard syndrome, or an anterior cervical cord syndrome.

• . A complete spinal cord injury is manifested by total motor and sensory loss distal to the injury. When the bulbocavernosus reflex is positive and no sacral sensation or motor function has returned, the paralysis will be permanent and complete in most patients

• Goals of Spine Trauma Care• Protect against further injury

during evaluation and management

• Expeditiously identify spine injury or document absence of spine injury

• Optimize conditions for maximal neurological recovery

• Maintain or restore spinal alignment • Minimize loss of spinal mobility • Obtain a healed and stable spinal

column • Facilitate rehabilitation

TIMING OF SURGERY • The timing of surgery for spinal

cord injuries is controversial. Most authors agree that in the presence of a progressive neurological deficit, emergency decompression is indicated

• indications for surgical treatment of thoracolumbar spine injuries include burst fractures with 50% or more canal compromise, 30 degrees or more of kyphosis, late neurological deficits, and clearly unstable fractures and fracture-dislocations.

• . In patients with complete spinal cord injuries or static incomplete spinal cord injuries,

• some authors advocate delaying surgery for several days to allow resolution of cord edema, whereas others favor early surgical stabilization

decompression• 1 anterior decompression and

fusion with instrumentation• 2 posterior decompression and

fusion with instrumentation• 3 combined anterior

decompression and posterior decompression

DECOMPRESSION • The role of decompression also is

controversial • Compression of the neural elements by

retropulsed bone fragments can be relieved indirectly by the insertion of posterior instrumentation or directly by exploration of the spinal canal through a posterolateral or anterior approach.

The posterolateral technique for decompression of the spinal canal is effective at the thoracolumbar junction and in the lumbar spine. This procedure involves hemilaminectomy and removal of a pedicle with a high-speed burr to allow posterolateral decompression of the dura along its anterior aspect

• risk and complications of surgery, including inadequate decompression,

• increased neurological deficit,• failure of internal fixation,• and the need for implant removal

Degree of canal stenosis

• no reliable correlation between the degree of compromise of the spinal canal and the severity of the neurological deficit.

Vertebral Compression Fractures

• They rarely are associated with neurological deficit, except when multiple adjacent vertebral levels are affected..

• Medical management is the mainstay of treatment for these acute, painful compression fractures and includes bed rest, analgesics, braces, and physical therapy

• Silverman showed that with each successive fracture, pulmonary force vital capacity was reduced by an average of 9%

• minimally invasive spinal surgery techniques have evolved, acutely painful vertebral compression fractures can be treated with a percutaneous procedure termed vertebroplasty.

• This procedure entails placing large spinal needles into the fractured vertebral body through a channel made in the pedicle and injecting bone cement into the fractured bone

Balloon Kyphoplasty • has evolved as the next step in

the treatment of vertebral compression fractures. This is a minimally invasive procedure that involves reduction and fixation.

Posterior instrumentation

• posterior instrumentation is a safe and effective treatment for thoracolumbar instability

• These implants have been developed because of the deficiencies of Harrington rods, such as breakage, cutting out of hooks, and loss of fixation

• . Biomechanical studies suggest that these newer devices offer improved fixation, but because they may be technically more difficult to insert, neurological risks are increased

• Anterior instrumentation has evolved significantly, now allowing correction of a deformity, stabilization of spinal segments during decompression, and bone grafting to be performed simultaneously. These implants are useful in the treatment of thoracolumbar burst fractures

• Anterior internal fixation devices allow treatment of mechanical instability and neurological compression in a single-stage surgical procedure

ANTERIOR VERTEBRAL BODY EXCISION FOR BURST FRACTURES

• may be selected primarily or may be necessary in certain burst fractures left untreated for more than 2 weeks and not believed to be candidates for posterior instrumentation and indirect decompression of the spinal canal

• Thank you………

Central cord syndrome • Central cord syndrome is the most common. It

consists of destruction of the central area of the spinal cord, including both Gray and white matter . The centrally located arm tracts in the cortical spinal area are the most severely affected, and the leg tracts are affected to a lesser extent

Central cord syndrome

• Sensory sparing is variable, but usually sacral pinprick sensation is preserved

• This syndrome usually results from a hyperextension injury in an older person with pre-existing osteoarthritis of the spine. The spinal cord is pinched between the vertebral body anteriorly and the buckling ligamentum flavum posteriorly

Incomplete cord lesion

Brown sequard syndrome

• brownSéquard syndrome is an injury to either half of the spinal cord and usually is the result of a unilateral laminar or pedicle fracture, penetrating injury, or a rotational injury resulting in a subluxation. It is characterized by motor weakness on the side of the lesion and the contralateral loss of pain and temperature sensation. Prognosis for recovery is good, with significant neurological improvement often occurring.

Anterior cord syndrome • Anterior cord syndrome is caused

by a hyperflexion injury in which bone or disc fragments compress the anterior spinal artery and cord.

• It is characterized by complete motor loss and loss of pain and temperature discrimination below the level of injury.

• The posterior columns are spared to varying degrees resulting in preservation of deep touch, position sense, and vibratory sensation.

• Prognosis for significant recovery in this injury is poor.

Posterior cord syndrome

• Posterior cord syndrome involves the dorsal columns of the spinal cord and produces loss of proprioception vibrating sense while preserving other sensory and motor functions. This syndrome is rare and usually is caused by an extension injury

A mixed syndrome• A mixed syndrome usually is an

unclassifiable combination of several syndromes. It describes the small percentage of incomplete spinal cord injuries that do not fit one of the previously described syndromes

Conus medullaris syndrome,

• Conus medullaris syndrome, or injury of the sacral cord (conus) and lumbar nerve roots within the spinal canal, usually results in areflexic bladder, bowel, and lower extremities.

• Most of these injuries occur between T11 and L2 and result in flaccid paralysis in the perineum and loss of all bladder and perianal muscle control.

• The irreversible nature of this injury to the sacral segments is evidenced by the absence of the bulbocavernosus reflex and the perianal wink.

• Motor function in the lower extremities between L1 and L4 may be present if nerve root sparing occurs.

Cauda equina syndrome

• Cauda equina syndrome, or injury between the conus and the lumbosacral nerve roots within the spinal canal, also results in areflexic bladder, bowel, and lower limbs. With a complete cauda equina injury, all peripheral nerves to the bowel, bladder, perianal area, and lower extremities are lost.

• the bulbocavernosus reflex, anal wink, and all reflex activity in the lower extremities are absent, indicating absence of any function in the cauda equina

Cauda equina syndrome

• widespread neurological disorder • Difficulty with micturition • Loss of anal sphincter tone or faecal incontinence • Saddle anesthesia about the anus, perineum or

genitals • Widespread (>one nerve root) or progressive

motor weakness in the legs or gait disturbance • Sensory level

Hypoxia• Lesions above C5 – damage to diaphragm leads to 20% reduction in vital

capacity

• Lesions at D4-6 – reduces vital capacity if < 500ml patient is ventilated

• Intercostal nerve paralysis• Atelectasis – poor cough

• V/Q mismatch• Reduced compliance of lung – muscle fatigue.

Neurogenic shock• Lesions above D6• Minutes – hours (fall of catecholamines may take 24 hrs)• Disruption of sympathetic outflow from D1 - L2• Unapposed vagal tone • Peripheral vasodilatation• Hypotension, Bradycardia & Hypothermia

• BUT consider haemmorhagic shock if – injury below D6, other major injuries, hypotension with spinal fracture alone without neurological injury.

Spinal shock• Transient physiological reflex depression of cord function –

‘concussion of spinal cord’

• Loss anal tone, reflexes, autonomic control within 24-72hr

• Flaccid paralysis bladder & bowel and sustained Priapism

• Lasts even days till reflex neural arcs below the level recovers.

• Thank you