Mechanical Disorders : Mechanical Disorders : Intervetebral DiscIntervetebral Disc

Dr Munir Saadeddin Dr Munir Saadeddin

Disorders of Intervertebral DiscDisorders of Intervertebral Disc

Are thought to be the cause of most Are thought to be the cause of most cases of low back paincases of low back pain

Are common at middle age Are common at middle age

Result from loss of hydration of the Result from loss of hydration of the Annulus Pulposis or major trauma to Annulus Pulposis or major trauma to disc disc

Function of Intervertebral Disc Function of Intervertebral Disc

It functions as a cushioning structure It functions as a cushioning structure

It is a structure of shock absorptionIt is a structure of shock absorption

The amount of pressure inside the The amount of pressure inside the disc varies according to posture of disc varies according to posture of humanhuman

Normally it does not encroach on Normally it does not encroach on spinal canal posteriorlyspinal canal posteriorly

Anatomy of Intervertebral DiscAnatomy of Intervertebral Disc

Anatomy of Intervertebral DiscAnatomy of Intervertebral Disc

Fresh Cadaver Specimen of a DiscFresh Cadaver Specimen of a Disc

Anatomy of Intervertebral discAnatomy of Intervertebral discThe disc is a biconvex structurThe disc is a biconvex structur

It consists of outer layer of Interlaced It consists of outer layer of Interlaced fibers called Annulus Fibrosis and central fibers called Annulus Fibrosis and central layer called Nucleolus Pulposislayer called Nucleolus Pulposis

The Nucleolus is soft, elastic and well The Nucleolus is soft, elastic and well hydrated structure at young agehydrated structure at young age

Pressure inside the DiscPressure inside the DiscLeast pressure is Least pressure is when person is lying when person is lying flatflat

Pressure increases 3 Pressure increases 3 folds on twisting in folds on twisting in bedbed

Pressure increases 4 Pressure increases 4 folds when standingfolds when standing

Pressure inside the DiscPressure inside the DiscPressure increases Pressure increases 6 folds on forward 6 folds on forward bendingbending

Pressure increases Pressure increases 10 folds on bending 10 folds on bending and lifting and lifting

This explains the This explains the most common most common cause for rupture of cause for rupture of intervertebral discintervertebral disc

Pressure inside the DiscPressure inside the Disc

Circumferential Tear in AnnulusCircumferential Tear in Annulus

Radial Tears of DiscRadial Tears of DiscRadial tears are more Radial tears are more serious than serious than circumferential tearscircumferential tears

Circumferential tears Circumferential tears cause deep seated cause deep seated backache but radial backache but radial tears may lead to tears may lead to bulge in the annulus bulge in the annulus inside the spinal canal inside the spinal canal or protrusion of or protrusion of nucleolus inside the nucleolus inside the canalcanal

Protrusion of Intervertebral DiscProtrusion of Intervertebral DiscUsually it is Usually it is posterolateralposterolateral as as the posterior the posterior longitudinal ligament longitudinal ligament resist central posterior resist central posterior protrusionsprotrusions

Central protrusions Central protrusions are usually small, but are usually small, but large protrusions are large protrusions are more serious as they more serious as they may cause may cause CaudaCauda EquinaEquina SyndromeSyndrome

Protrusion of DiscProtrusion of Disc

Nerve Root Protrusion by PIDNerve Root Protrusion by PIDProtrusion of Protrusion of Intervertebral disc Intervertebral disc may compress the may compress the nerve root exiting nerve root exiting spinal canal at that spinal canal at that level and may cause level and may cause inflammatory changeinflammatory change

Protrusion at L4-L5 Protrusion at L4-L5 compresses L5compresses L5

Protrusion at L5-S1 Protrusion at L5-S1 compresses S1 compresses S1

Central Disc ProtrusionsCentral Disc ProtrusionsMay compress More May compress More than one nerve rootthan one nerve root

It does compress It does compress central roots like S2 central roots like S2 S3 / S4S3 / S4

This leads to This leads to compression of nerve compression of nerve roots to bladder and roots to bladder and rectum ( rectum ( CaudaCauda Equina Syndrome )Equina Syndrome )

Clinical Picture of PIDClinical Picture of PID

Clinical Picture of PIDClinical Picture of PID

A middle age malA middle age mal

May present with LBP and or Sciatica May present with LBP and or Sciatica (Though sciatica in Arabic is referred (Though sciatica in Arabic is referred to as painful leg in women )to as painful leg in women )

Sometimes follows clear incident of Sometimes follows clear incident of heavy lifting or back strainingheavy lifting or back straining

Frequently NO history of any cause is Frequently NO history of any cause is presentpresent

Clinical Picture of PIDClinical Picture of PID

May present as : Acute , Recurrent May present as : Acute , Recurrent or Chronicor Chronic

In Acute cases patient may report In Acute cases patient may report that he felt a tear or a click at his that he felt a tear or a click at his backback

This may be followed by immediate This may be followed by immediate radiation of pain to leg or notradiation of pain to leg or not

Radiation to leg may appear laterRadiation to leg may appear later

Clinical Picture of PIDClinical Picture of PIDThis is NOT a systemic diseaseThis is NOT a systemic diseaseThere is NO fever or weight lossThere is NO fever or weight lossPAIN IS MECHANICAL i.e. : it follows PAIN IS MECHANICAL i.e. : it follows some posture which increases the some posture which increases the intervertebral disc pressureintervertebral disc pressureConstant pain or nocturnal (night) Constant pain or nocturnal (night) pain is a sinister signpain is a sinister signPain is increased by coughing and Pain is increased by coughing and relieved by lying in bedrelieved by lying in bed

Usually it is the Usually it is the lower backlower back

Commonly there is Commonly there is Para vertebral Para vertebral muscle spasm muscle spasm

We palpate the We palpate the level of Iliac Crest level of Iliac Crest = level of L4-L5= level of L4-L5

Palpation in Back ExaminationPalpation in Back Examination

We can palpate the We can palpate the Para Spinal Para Spinal muscles ,tips of muscles ,tips of spinous processes spinous processes and the inter spinal and the inter spinal ligamentligament

We cannot palpate We cannot palpate the lamina , the disc the lamina , the disc or vertebral bodyor vertebral body

Palpation in Back ExaminationPalpation in Back ExaminationWe start by We start by identifying the identifying the level of Iliac Crestlevel of Iliac Crest

This corresponds to This corresponds to L4-L5L4-L5

Almost 5 cm below Almost 5 cm below is L5-S1is L5-S1

Below on the sides Below on the sides there is a dimple there is a dimple which corresponds which corresponds to upper S.I. Joint to upper S.I. Joint

Palpation in Back examinationPalpation in Back examinationLesions at L4-L5 Lesions at L4-L5 will produce will produce tenderness at L4-tenderness at L4-L5 levelL5 level

Lesions at L5-S1 Lesions at L5-S1 will produce will produce tenderness at L5-tenderness at L5-S1 levelS1 level

We can palpate for We can palpate for tenderness at tenderness at Sciatic Nerve Sciatic Nerve course as wellcourse as well

Examination of Back Movements: Examination of Back Movements: Forward FlexionForward Flexion

Forward flexion is 90 Forward flexion is 90 degrees or when degrees or when tips of fingers reach tips of fingers reach level of malleolilevel of malleoli

Flexion to level of Flexion to level of mid-tibia is 60 mid-tibia is 60 degreesdegrees

Flexion to knees is Flexion to knees is 45 degrees45 degrees

Flexion to mid-Thigh Flexion to mid-Thigh is 30 degreesis 30 degrees

Examination of back movements: Examination of back movements: Back Extension Back Extension

From straight to 30 degreesFrom straight to 30 degrees

Some people can do much more Some people can do much more (Gymnastics or people with ligament (Gymnastics or people with ligament laxity )laxity )

Back extension is reduced or lost in Back extension is reduced or lost in people with acute PID ( It may be people with acute PID ( It may be even –Minus extension as they may even –Minus extension as they may walk with flexed back )walk with flexed back )

Examination of Back Movements:Examination of Back Movements:Lateral FlexionLateral Flexion

Lateral flexion is 30 Lateral flexion is 30 degrees to right or degrees to right or leftleft

Lateral flexion to the Lateral flexion to the same side of pain is same side of pain is always restricted always restricted (except in case of (except in case of axial disc herniation) axial disc herniation)

Examination of Back Movements: Examination of Back Movements: RotationRotation

May be done in EITHER standing or sitting May be done in EITHER standing or sitting positionspositions

In standing position examiner has to In standing position examiner has to immobilise the pelvis of the patient to immobilise the pelvis of the patient to make sure than there is no rotation of make sure than there is no rotation of whole bodywhole body

In sitting position body weight immobilises In sitting position body weight immobilises the pelvis and probably more accuratethe pelvis and probably more accurate

Walking on Heels = L5Walking on Heels = L5Asking the patient to Asking the patient to stand and walk on his stand and walk on his heels elicit if there is heels elicit if there is any weakness at L5 any weakness at L5 (which is main nerve (which is main nerve root for All 3 muscles root for All 3 muscles of dorsiflexion = of dorsiflexion = Tibialis Anterior , Tibialis Anterior , Extensor Digitorum Extensor Digitorum and Extensor Hallucis and Extensor Hallucis Longus) Longus)

Walking on Tip Toes = S1Walking on Tip Toes = S1Asking the patient to Asking the patient to stand and walk on tip stand and walk on tip toes elicit if there is toes elicit if there is any weakness of S1 any weakness of S1 (which is the main (which is the main nerve root for nerve root for muscles of plantar muscles of plantar flexion = flexion = Gastocnemius and Gastocnemius and SoleusSoleus

Examination in Supine positionExamination in Supine position

Once we ask patient to lie down in Once we ask patient to lie down in bed we start examining certain testsbed we start examining certain tests

This does NOT include inspection of This does NOT include inspection of the backthe back

Most important is SLR test ( Straight Most important is SLR test ( Straight Leg Raising Test ) and Neurological Leg Raising Test ) and Neurological assessment for the condition assessment for the condition

Straight Leg Raising TestStraight Leg Raising Test

SLR TestSLR TestIt is a It is a Sciatic NerveSciatic Nerve StretchStretch Test Test

Normally it is Normally it is PainlessPainless

Is done in supine Is done in supine positionposition

Normal from 0-90Normal from 0-90 degreesdegrees

ReliableReliable test is test is between between 30-8030-80

Lasague ManeuverLasague Maneuver

Lasague Maneuver Lasague Maneuver Lasague Maneuver is Lasague Maneuver is a a modified SLR testmodified SLR test

It has It has 3 advantages3 advantages

It is a confirmatory It is a confirmatory test for SLRtest for SLR

It excludes hip or It excludes hip or knee pain as a cause knee pain as a cause for the pain on SLRfor the pain on SLR

It excludes It excludes malingering patients malingering patients

Lesions of L3-4 and L4-5Lesions of L3-4 and L4-5

Lesions of L4-5 and L5-S1Lesions of L4-5 and L5-S1

Investigations of Backache : x raysInvestigations of Backache : x raysPlain X Rays are usefulPlain X Rays are useful

AP, Lateral and Oblique AP, Lateral and Oblique may be donemay be done

On this On this laterallateral view view there is obvious sign there is obvious sign == Loss of normal lordosis Loss of normal lordosis ==straitening of lumbar straitening of lumbar spine spine

Investigations of Backache : x raysInvestigations of Backache : x raysLateral view or Lateral view or cone cone view demonstrate view demonstrate narrowed disc spacenarrowed disc space

Also this view Also this view demonstrates gas demonstrates gas shadow in disc shadow in disc space= chronicity= space= chronicity= Knott’s sign = Knott’s sign = vacuum vacuum phenomenonphenomenon

Myelography and radiculography Myelography and radiculography

Used to be the most Used to be the most important test for important test for eliciting disc eliciting disc protrusionsprotrusions

NOT used these NOT used these days for the above days for the above diagnosisdiagnosis

Still used for Still used for investigating certain investigating certain intra spinal and intra spinal and instability conditionsinstability conditions

C.T. Scan Disc ProtrusionC.T. Scan Disc Protrusion

C.T. MyelographyC.T. Myelography

MRI L4-5 PIDMRI L4-5 PID

MRI : P I DMRI : P I D

MRI : PID=LDHMRI : PID=LDH

MRI : PID = LDHMRI : PID = LDH

Management of PIDManagement of PID

Essentially conservativeEssentially conservative

Almost 85% respond to conservative Almost 85% respond to conservative treatmenttreatment

Up to 15% surgical treatment is Up to 15% surgical treatment is indicatedindicated

Severity of symptoms does not Severity of symptoms does not indicate severity of diseaseindicate severity of disease

Conservative TreatmentConservative TreatmentShould be tried initially in most casesShould be tried initially in most casesShort period of Bed Rest (< 1 week ) Short period of Bed Rest (< 1 week ) should be tried in ACUTE casesshould be tried in ACUTE casesBed rest is NOT indicated in chronic Bed rest is NOT indicated in chronic casescasesNSAID’s and muscle relaxants are NSAID’s and muscle relaxants are used ( Drugs to protect against G.I. used ( Drugs to protect against G.I. effects especially in the elderly )effects especially in the elderly )Avoids narcoticsAvoids narcotics

Physiotherapy and ExercisesPhysiotherapy and ExercisesAre the most important tools in Are the most important tools in managementmanagement

Always should be part of treatmentAlways should be part of treatment

Weight reduction and back care educationWeight reduction and back care education

Heat therapy especially Short Wave Heat therapy especially Short Wave diathermy and Ultrasound important types diathermy and Ultrasound important types of treatmentsof treatments

Exercises to strengthen back and Exercises to strengthen back and abdominal muscles should be done abdominal muscles should be done

Chiropractic Therapy & Chiropractic Therapy & AcupunctureAcupuncture

Recently gaining popularityRecently gaining popularityChiropractics means re-alignment of Chiropractics means re-alignment of bones and joints to normal structure bones and joints to normal structure (However once we understand the (However once we understand the pathology of PID, it is difficult to see pathology of PID, it is difficult to see how can a disc be put back in place!)how can a disc be put back in place!)Acupuncture is by stimulating Acupuncture is by stimulating specific points by needles and is specific points by needles and is helpful in some patientshelpful in some patients

Steroid Injections In PIDSteroid Injections In PID

In selected cases they are valuable In selected cases they are valuable adjuvant to other modalities of adjuvant to other modalities of treatment treatment

They are injected in the Extradural They are injected in the Extradural space by lumbar or caudal routespace by lumbar or caudal route

It is believed they work by reducing It is believed they work by reducing the inflammatory changes in the the inflammatory changes in the nerve root associated with PIDnerve root associated with PID

Surgery in PIDSurgery in PIDRadiological evidence MUST be Radiological evidence MUST be obtained prior to surgeryobtained prior to surgeryTheses radiological changes MUST Theses radiological changes MUST correspond with the clinical picturecorrespond with the clinical pictureWe have to remember that NOT We have to remember that NOT every bulging disc should be every bulging disc should be operated onoperated onMRI is the golden standard in MRI is the golden standard in diagnosisdiagnosis

Indications for Surgery for PIDIndications for Surgery for PID

There are Five indicationsThere are Five indications

Only one definite and urgent Only one definite and urgent indication in indication in CAUDA EQUINA CAUDA EQUINA syndromesyndrome

Three valid and correct indications Three valid and correct indications (will be explained soon )(will be explained soon )

One controversial and personal One controversial and personal indicationindication

Valid Indications for Surgery in PIDValid Indications for Surgery in PID

Failure of conservative treatment ( Failure of conservative treatment ( for at least 6 weeks ) and for at least 6 weeks ) and continuation of paincontinuation of pain

Progression of neurological deficit Progression of neurological deficit (but initial deficit is not an absolute (but initial deficit is not an absolute indication )indication )

Recurrent and disturbing attacks Recurrent and disturbing attacks

Controversial indications in PIDControversial indications in PID

Time Factor : Patient is not prepared Time Factor : Patient is not prepared to complete a full period of to complete a full period of conservative treatment ( 6 weeks ) conservative treatment ( 6 weeks ) to see if it will succeed to see if it will succeed

Patient’s preferencePatient’s preference

Surgeon’s preferenceSurgeon’s preference

Exclude a psychological causesExclude a psychological causes

Operative procedures for PIDOperative procedures for PIDAt least 15% of cases of PID end up At least 15% of cases of PID end up having surgeryhaving surgeryAt USA : at least 250 000 cases are At USA : at least 250 000 cases are operated on annuallyoperated on annuallyAt USA : there are 7 million At USA : there are 7 million individuals who had back surgeryindividuals who had back surgeryStill at USA : there are 21 million Still at USA : there are 21 million people with disability certificate due people with disability certificate due to backache !to backache !

Aim of surgery for PIDAim of surgery for PIDTo relieve patient of his painTo relieve patient of his pain

Leg pain can be relieved by removing Leg pain can be relieved by removing pressure on nerve root pressure on nerve root ( Decompression of nerve root )( Decompression of nerve root )

This is done by removing the bulged or This is done by removing the bulged or protruded part of the disc and any other protruded part of the disc and any other part which can be curetted outpart which can be curetted out

Back pain can be relieved by stabilising Back pain can be relieved by stabilising that intervertebral disc segment that intervertebral disc segment

Position for surgery for PIDPosition for surgery for PID

Position for surgery for PIDPosition for surgery for PIDUsually it is Chest-Knee positionUsually it is Chest-Knee position

This is to avoid any pressure on This is to avoid any pressure on abdomenabdomenAvoidance of pressure on abdomen Avoidance of pressure on abdomen reduces intra abdominal pressure reduces intra abdominal pressure and consequently reduces intra and consequently reduces intra spinal pressure = reduction of spinal pressure = reduction of venous bleeding from dural veinsvenous bleeding from dural veins

Open Disc SurgeryOpen Disc Surgery3-5 cm for each disc 3-5 cm for each disc levellevel

Lamina above and Lamina above and lamina below are lamina below are exposed with the part exposed with the part of Ligamentum of Ligamentum Flavum betweenFlavum between

Part of Ligamentum Part of Ligamentum Flavum and lamina is Flavum and lamina is removed to get removed to get access to spinal canalaccess to spinal canal

Open Disc SurgeryOpen Disc Surgery

Exposure of Dura and Nerve RootExposure of Dura and Nerve Root

Excision of protruded PIDExcision of protruded PIDDura is retracted with Dura is retracted with the nerve root to the nerve root to expose the protruded expose the protruded PIDPID

Once protrusion is Once protrusion is exposed it is incised in exposed it is incised in 5x5 mm cruciate 5x5 mm cruciate incisionincision

Occasionally nucleolus Occasionally nucleolus is already penetrated is already penetrated through the annuulusthrough the annuulus

Excision of PIDExcision of PIDProtruded or extruded Protruded or extruded disc is removed and disc is removed and disc space curetteddisc space curetted

Nerve root should be Nerve root should be Free from any Free from any compressioncompression and and Free from Free from tensiontension

If any bone was If any bone was involved it should be involved it should be removedremoved

Endoscopic Micro- Discectomy Endoscopic Micro- Discectomy Relatively New method of Disc SurgeryRelatively New method of Disc Surgery

Minimally traumatic in experienced handsMinimally traumatic in experienced hands

Minimal scar and blood lossMinimal scar and blood loss

Requires high quality surgical toolsRequires high quality surgical tools

Fluoroscopy pre and during surgery is Fluoroscopy pre and during surgery is necessarynecessary

Nerve root injury may be as high or even Nerve root injury may be as high or even higher than with other methodshigher than with other methods

Endoscopic Micro- DiscectomyEndoscopic Micro- Discectomy

Endoscopic Micro- DiscectomyEndoscopic Micro- Discectomy

Percutaneous Discectomy Percutaneous Discectomy Is done through a cannula inserted lateral Is done through a cannula inserted lateral to midline into disc space under G.A. or to midline into disc space under G.A. or L.A. and nucleolus is sucked with shaverL.A. and nucleolus is sucked with shaver

Initially was thought to be easy and simpleInitially was thought to be easy and simple

Has not proved to be very successfulHas not proved to be very successful

Reported success rate is 70%Reported success rate is 70%

Patient and surgeon are exposed to Patient and surgeon are exposed to repeated radiationrepeated radiation

Percutaneous Discectomy Percutaneous Discectomy

Laser DiscectomyLaser DiscectomyMay become the golden standard for May become the golden standard for managing PID in the future managing PID in the future ( especially when open MRI machines ( especially when open MRI machines are available )are available )Route of entry is similar to Route of entry is similar to Percutaneous DiscectomyPercutaneous DiscectomyCan be done under local or general Can be done under local or general anesthesia anesthesia Not perfect at presentNot perfect at present