Lumbar disc herniationManagement of free fragments

Part 1

Vinod NaneriaConsultant orthopaedic surgeon

Choithram Hospital & Research CentreIndore, India

• A piece of nucleus pulposus with annulus fribrosus & fragments of cartilagenous end-plate, lying loose in the spinal canal.

• It may migrate up or down a level or two, may migrate posterior to dura or perforate dura. Incidence - 9 to 15.5%

Free fragment

Types of Disk Disease Disk Bulge

Disk bulges into anterior epidural space without any area of focal-ness or out-pouching

Disk HerniationGeneral term used to describe different degrees of 'eccentric out-pouching' of IV disk.

Protrusion

contained herniation or sub-ligamentous herniation

Extrusion

non-contained herniation, or trans-ligamentous herniation

Sequestration

free fragment

Free Fragments Free Fragments

Loose Fragments

Literature – Free Fragment

• Incidence - 9 to 15.5% • Composition – N.P. / A.F. + fragments of end plate• Lateral migration – cranial & caudal• Posterior migration – cauda equina – mimic tumour• Intra dural more than 60 cases reported-world

literature• Roof disc : central disc extrusion : contained by

P.L.L.

Migration

• Since it is impossible to predict on MRI, that a migrated fragment have some continuity with the parent disc or not - it should be considered as loose fragment.

• There is a real possibility of migration of the fragment and increase in the neuro-deficit.

• It is immaterial where the migration is.• Migration may progress in the initial phase of

extrusion, it may migrate one or two level – up or down.

Composition of extruded material

• Nucleolus pulposus

• Annulus fibrosus

• Fragments of cartilage end plate.

Pathophysiology of Absorption

• The disc formation takes place before the immune system develops in the embryonic life.

• The proteins in the nucleosus pulposus are foreign to immune system in adults.

• The free fragment is treated as foreign protein and a reactive granuloma forms, which absorbs the free fragment.

Absorption - Composition & Time

• Nucleolus Puplposus– absorb by formation of granulation tissue possibly as

an auto-immune reaction– 3 months

• Annulus Fibrosus– absorb by granulation tissue by vascular invasion– 1 – 2 years

• Hyline cartilage of end-plate– suppresses neo-vascularization– resistant to absorb

• The amount of hyaline cartilage, should be predictable on the basis of imaging data.

• Vertebral endplate marrow signal intensity changes are associated with fissures in the vertebral end-plate.

• Signal intensity changes may be regarded as osteo cartilaginous fracture signs similar to other skeletal manifestations.

MRI – showing End-plate lesion, marrow signalsIndicating a portion of end-plate avulsion in the extruded disc &Will take long time to absorbed or reduction in size.Early surgery may be contemplated.

Fate of Free Fragment – Complete absorption

• Sei A, Nakamura T et al 1994 • Coevoet V et al t.d. 1997• Westmark RM et al c.d. 1997• Miller S et al 1998• Singh P, Singh AP. 1998• Morandi X et al 1999• Kobayashi N et al c.d. 2003

More than 55% of absorption is clinically significantFollow up MRI – every 3 months for one year

Spontaneous changes on MRI & Clinical Correlation

- 42 cases treated conservatively.

Takada & Takahashi

• MRI changes Cases Excellent Good Poor

Disappearance 08 06 02 00

More 50% 29 11 18 00

No reduction 05 00 01 04

50% involution in 3 – 6 monthsJ.of Orthopaedic Surgery 2001, 9(1): 1–7

Upward behind body

Lateral Migration

Case history – 2 - Monoradiculopathy

L4 – L5 with loose fragment over L5 bodyEHL drop gr. 2

Complete relief 2 Yr FU

Downward Migration

Why conservative?

• Stable neurological deficit & Presented late > than one week.

• Bearable radicular pain with negative root stretching test (SLRT).

• No bladder or bowel dysfunction.

• Patient not willing for surgery but gave consent for surgery as & when needed. Kept under strict watchful supervision.

R.K.- Absorption one month

• A 25 M• Acute agonizing pain 5 days duration• Spinal flexion 50%, EHL lt weak gr3• No bladder – bowel dysfunction.• Pain minimal• MRI extruded disc at L5-S1 left• Repeat MRI after one month – extruded

fragment (N.P.)absorbed completely.

Jan2007 Feb

2007

Absorption within 3 months

• R.J. – 55 male,

• Backache sciatica rt., acute onset.

• Rt. Ankle jerk absent.

• MRI-June 07- extruded fragment L5-S1

• Conservative

• MRI – Aug 07- complete absorption

Completeabsorptionin threemonths.

N.K.- Complete absorption one year

• H/o backache sciatica 2005 – MRI degenerated discs at L4-L5, L5-S1.

• Extruded disc in 2006 – with no neurological deficit.

• Tx – conservatively with complete absorption of free fragment.

2005

2006

2006

2006

2007

Case history – U.S.

• 45 M,• Acute backache sciatica 15 days duration• Attended clinic as OPD patient.• L5 – S1 Rt. with loose fragment over L5 body• Measuring 2.4cm x 1.5cm• Full flexion spine and negative SLRT• Mild gr.4 weakness in EHL and Hypoasthesia in

L5 distribution.• Tx conservatively