Treating Chronic Back Pain: New Knowledge, More Choices

MBBS, MD (Anesthesiology), FIPP Director. Interventional Pain and Spine Centre

New Delhi ,India

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Normal Architecture of the Disc

Pathophysiology of Disc related pain

Intradiscal Procedures for

Discogenic pain Herniated disc

INTERVERTEBRAL DISC

Irregular network of collagen fibers type II (viscocity) > type I and elastin fibers

Proteoglycans( Agrrecan)-Osmotic properties to resist compression

Nucleous Pulposus

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ANNULUS FIBROSUSANNULUS FIBROSUS

Callagen fibers type I (Thickness) > type II

Runs oblique in alternating direction ---Tensile strength

Also contains some proteoglycans and Elastin fibers

END PLATE

Approx 1 mm thick Considered part of disc rather than body Made up of hyaline cartilage mostly (young) and

fibrocartilage (old) The collagen fibers of the inner 2/3rds of the

annulus form the fibro cartilaginous component of the VEP

LUMBAR INTERVERTEBRAL DISC

- NERVE INNERVATION

Outer 1/3rds of the annulus circumferentially Posterior plexus - Sinuvertebral nerves stems from Rami

Communicans Anterior plexus formed by bridging of sympathetic trunks and

the proximal ends of the GRCs

BLOOD SUPPLY AND NUTRITION

Capillaries arise in Vertebral body

Penetrates Subchondral Bone

Terminates at Vertebral End Plates

Diffusion

O 2 and glucose

Lactic acid

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Pathophysiology

Disc Degeneration –Internal Disc Disruption- Discogenic pain- Disc Herniation

Decrease in end plate Permiability

Failure of nutrient supply&

Accumulation of waste

Low p H

Injury

Pathophysiology-Disc Degeneration

PATHOPHYSIOLOGY-DISC DEGENERATION

Loss of Proteoglycan & collagen and degradation

Fall in osmotic pressure of disc matrix

No longer behaves hydrostatically under

load

Loose height and fluid more rapidly

Stress concentration along

End plates and Annuluswww.ipscindia.com

INTERNAL DISC DISRUPTION

PATHOPHYSIOLOGY-INTERNAL DISC

DISRUPTION

Normal Disc – Pressure evenly distributed along end plates and annulus

• Degenerated disc – Uneven stress across End plates and annulus –Fissures and Tear

INTERNAL DISC DISRUPTION

Annular tear and fissures

PATHOPHYSIOLOGY-DISCOGENIC PAIN

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Only outer 1/3 is innervated

Now the whole disc

can feel

RISK FACTORS –DISC DEGENERATION

Age:Vascular changes e.g. AtherosclerosisEnd Plate changes e.g. calcificationSub cortical sclerosis

Genetic factors :

Aggrecan gene polymorphism

RISK FACTORS

Smoking and IVD Degeneration .Spine 1991: Sep; 16(9): 1015-21

Sally Roberts, Jill P.G. Urban

Life style:Life style:

Lack of ExerciseObesity

Smoking

Prolonged sitting

Aging of Disc Degeneration of Disc

• Affects Nucleous

• Increased proteoglycan fragmentation and water content is decreased

• Nucleus is gradually replaced by collagen fibers.

• Disc height is maintained.

• Look black on T2 weighted image of MRI

• Annulus & End plates

• Concentric or radial tear in the annulus, Inwards buckling of annulus & radial bulging of outer annulus

• Endplate defects & vertical bulging of endplates into the adjacent vertebral bodies.

• Reduced disc height

• Look black on T2 weighted image of MRI

Plain Radiographs

Investigations

C T SCAN

•The vacuum disc phenomenon

•Loss of disc height.

•Secondary findings of disc degeneration, Endplate sclerosis

Osteophyte formation

MRI

Test of Choice

Architecture of Disc Disruption of endplates Secondary changes Herniation

HIZ

MRI

The pathogenesis and clinical significance of a high-intensity zone (HIZ) of lumbar intervertebral disc on MR imaging in the patient with discogenic low back pain.Eur Spine J. 2005 Jul 27

Fibrovascular ingrowth into region of Annular tear

MODIC CHANGES SECONDARY TO DISC DEGENERATION

MRI

Type III Low signal in T1 and low signal

in T2--sclerotic changes.

Type- I Low signal in T1-weighed

sequences and high signal in T2)---edema.

Type II High signal in T1-weighed sequences and either high or intermediate signal in T2) ---fatty replacement

FACET ARTHROPATHY SECONDARY TO DISC

DEGENERATION

Disc bears 80% of weight Facet joints bears 20 % of weight

A change in the intervertebral disc producesChange in the whole motion segment

MRI

Ligamental Buckling Degenerative Changes –Intraspinal Ligaments

MRI

GRADES OF DISC DEGENERATION

Magnetic Resonance Classification of Lumbar Intervertebral Disc DegenerationSPINE Volume 26, Number 17, pp 1873–1878

MODIFIED PFIRRMANN GRADING SYSTEM-

8 GRADES

Modified Pfirrmann Grading System for Lumbar Intervertebral Disc Degeneration Spine: 15 November 2007 - Volume 32 - Issue 24 - pp E708-E712

Intradiscal Procedures

DISCOGRAPHY

DISCOGRAPHY -3 COMPONENTS

PROVOCATIVE DISCOGRAPHY-DERBY’S CLASSIFICATION-PAIN PROVOCATION AND DISCOMETRY

Pain @ <15 psi - chemically sensitive

Pain @ 15-50 psi - mechanically sensitive

Pain @ 51-90 psi - intermediate

Pain @ >90 psi - normal disc

No Pain - normal disc

POST DISCOGRAPHY CT SCAN-(3RD STEP)MODIFIED DALLAS GRADES

Grade 0 – Normal disc, cotton ball appearance Grade 1 – Radial tear upto inner 1/3 of AF Grade 2 – Radial tear upto middle 1/3 of AF Grade 3 – Radial tear upto outer 1/3 of AF, but

extends < 30 degrees of disc circumference Grade 4 – Radial tear upto outer 1/3 of AF &

extends > 30 degrees of disc circumference Grade 5 – Radial tear with extra-annular leakage

into epidural space.

Site and Extent of Tear

Disc stimulation + Discography = Provocative DiscographyStep 1 and 2 Step 3

Interventions for Discogenic pain Contained Disc Herniation

Level of Evidence

Level of Evidence

Description Implications

1A + RCT’s( good quality) . Benefit >> Risk

1B + RCT’s(methodological weakness). Benefit >> Risk

Positive Recommendations

2B + RCT’s(methodological weakness). Benefit > Risk

2B + RCT’s(methodological weakness). Contradictory results

Considered

2C + Observational Studies. No conclusive evidence

0 Case reports. Insufficient evidence Only study related

2C - Observational studies- no effectiveness Negative Recommendations

2B - RCT’s –No effectiveness. Benefit << Risk

Indication Mild to moderate Degeneration Absent radicular symptom Positive discogram 1week-IDET

Contraindication Large disc herniation Canal stenosis Disc height loss > 50%

Mechanism of Action strengthen the collagen fibers, Seal fissures, denature inflammatory exudates, or coagulate

nociceptors

IDET

Nerve fiber damage

Stabilization of fissures

Temperature- 65 degree to 90

degree

16 min

Saal JS, Saal JA. Management of chronic discogenic low back pain with a thermal intradiscal catheter: a preliminary report. Spine. 2000;25:382-8

Freeman BJ, Fraser RD, Cain CM. et al. A randomized, double-blind, controlled trial: intradiscal electrothermal therapy versus placebo for the treatment of chronic discogenic low back pain. Spine. 2005;30:2369-77

Nunley PD, Jawahar A, Brandao SM. et al. Intradiscal electrothermal therapy (IDET) for low back pain in worker's compensation patients: can it provide a potential answer? Long-term results. J Spinal Disord Tech. 2008;21:11-8

POSTERIOR ANNULOPLASTY

Electrodes (Disctrode) – Placed in Posterior Annulus

NUCLEOPLASTY OR RF COBLATION

Bipolar radiofrequency probe Coblation (molecular

dissociation) technology to ablate tissue

Thermal energy for coagulation

•125 V of Energy•60-70 degree

Perc-D Spine Wand

(Courtesy of Arthrocare Spine, Sunnyvale, CA.)

NUCLEOPLASTY OR RF COBLATION

Indication Discogenic pain

with contained disc herniation

(No prospective randomized controlled studies for purely Discogenic pain)

Contraindication Extruded disc

Disc herniation >33 % of sagittal diameter of spinal canal

BIACUPLASTY

Kapural L, Mekhail N. Novel Intradiscal Biacuplasty (IDB) for the treatment of Lumbar Discogenic Pain. PainPractice J. 2007;7:130–135.

Insufficient number of studies about its efficacy and safety the preliminary findings show that this method was effective and safe.

Kapural L, Mekhail N. Novel Intradiscal Biacuplasty (IDB) for the Treatment of Lumbar Discogenic Pain. Pain Practice. 2007;7:130-4

Kapural L, Ng A, Dalton J. et al. Intervertebral disc biacuplasty for the treatment of lumbar discogenic pain: results of a six-month follow-up. Pain Med. 2008;9:60-7

INTRADISCAL STEROID

•Eur Spine J (2007) 16:925–931Buttermann GR (2004) The effect of spinal steroid injections for Degenerative disc disease. Spine J 4:495–505

• Prevent Inflammatory cascade

• Modic Type – I

Intradiscal Injections

METHYLENE BLUE

• Weak Neurolytic effect

• Inhibition of Guanylate Cyclase and NO synthesis

Intradiscal Injections

PAIN: Volume 149, Issue 1 , Pages 124-129, April 2010

INTRADISCAL OZONE

Anti-inflammatory properties

Primary Indicaction is Radicular Pain.

Intradiscal Injections

Eur J Radiol 2009 Dec; 72(3) :499-504.

INTRADISCAL PROCEDURES FOR DISC PROLAPSE

INDICATIONS OF PERCUTANEOUS MECHANICAL DISC DECOMPRESSION

Unilateral leg pain greater than back pain. Radicular symptoms in a specific dermatomal

distribution that correlates with MRI findings. Positive straight leg raising test or positive bowstring

sign, or both. No improvement after 6 weeks of conservative

therapy. Imaging studies (CT, MRI, discography) indicating a

subligamentous contained disc herniation. Well maintained disc height of 60%.

PERCUTANEOUS DISC DECOMPRESSION

Rotating probe is inserted through needle into the disc under X-Ray/ Fluoroscopic guidance

Rotating tip removes small portion of disc material.

Because only enough of the disc is removed to reduce pressure inside the disc, the spine remains stable.

NUCLEOTOMY

The herniation suctioned toward the probe where an integrated knife then cuts it away from the disk. The material is then suctioned away

HYDRODISCECTOMY

Cutting with water fluidJet technology uses the Venturi Effect created by high velocity

saline jets to cut and aspirate targeted tissue

OZONE DISCECTOMY/ OZONUCLEOLYSIS

It’s action is due to the active oxygen atom (singlet oxygen) liberated from it.

It attaches with the proteo-glycan bridges in the nucleus pulposus.

They are broken down and they no longer capable of holding water.

As a result disc shrinks and mummified and there is decompression of nerve roots.

Glucosamine and chondrointin sulphate-

Enhance the Repair response of chondrocytes and retard the enzymatic degradation of cartilage.

Cell based Therapies

Stimulate the disc cell to produce matrixDirect injection of Growth factor/ Cytokine inhibitor- Unsuccessful

Gene of interest is introduced into target cell

Nucleous Pulposus augmentation

Injectable Nucleous –Solution of Protein polymer and crosslinking agent

Regenerative Therapies

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