Degenerative Lumbar Spine Disease

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Degenerative Lumbar Spine

Disease

Michael Barnett, HMS III

Core Radiology Clerkship

BIDMC PCE

Beth Israel Deaconess

Harvard

Medical Center

Medical

A Member of

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Overview

Patient Presentation: Ms. S

Clinical Work-up of Low Back Pain

Menu of Radiological Tests

Lumbar Spine Anatomy

Patient Imaging: Ms. S

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Our Patient, Ms. S

88 year old woman with chronic low back

pain

4 year history of back pain

Radiation: left hip, thigh, calf, ankle

L5 dermatome distribution

The pain is inconstant

Relief with sitting

Ms. S is normally an active woman

Controls pain with Celebrex and epidural steroid

injections

Presents to the pain clinic after 3 epidural

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Clinical DDx Low Back Pain

Musculoskeletal

Bone

Fracture, spondylosis, spondylolisthesis

Joints

Facet joint degeneration

Disks

Herniation, annular tears

Ligaments

Ligament hypertrophy or

ossification

Muscles

Strain

Adapted from Stern, SD, Cifu AS and Altkorn D, From Symptom to Diagnosis, McGraw-Hill: NY, 2006.

Systemic Disease

Infection

Osteomyelitis, spondylodiscitis, epidural abscess

Inflammatory Arthritis

RA, AS, Psoriasis

Neoplastic

Primary tumors, metasstatic cancecr,

lymphoma, multiple myeloma

Visceral Condition

CV: Aortic aneurysm GU: stones, infection GI: pancreatitis, ulcers Gyn: Endometriosis, PID

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Low Back Pain

A challenging issue in outpatient

medicine

Point prevalence as high as

33%

Lifetime prevalence as high as

80%

Fifth

most common reason for physician

visits in US

1 in 5 patients report

substantial

limitations

in activity due to LBP

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Low Back Pain Work-Up

Imaging can create more questions than

answers

Especially in the elderly, degenerative spinal

is incredibly common

in asymptomatic

subjects

Disk herniation: 25-50%

Disk degeneration: 25-70%

Annular tears: 14-33%

Most LBP

resolves spontaneously

, as do

many radiographic findings

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However, it is important to be

aware of red flags which

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Red Flags

with LBP

Fracture

Age >70 History of osteoporosis Trauma Corticosteroid use

Adapted from Stern, SD, Cifu AS and Altkorn D, From Symptom to Diagnosis, McGraw-Hill: NY, 2006 and Lieberman, G Primary Care Radiology:Radiologic assessment of low back pain, http://eradiology.bidmc.harvard.edu/primarycare/index.html Accessed 10/17/2008

Infection

Fever, chills

Recent skin or urinary infection

Immunosuppresion

IVDU

Recent spine surgery

Neurologic

Sciatica

New onset urinary/fecal incontinence

Abnormal neurologic exam: motor, sensory, reflexes

Tumor

Age >50 History of previous cancer Unexplained weight loss

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Menu of Tests for Low Back Pain

Assessment

More Commonly Used:

Plain Films

CT and CT Myelography

MRI

Bone Scintigraphy -

assessing for metastatic cancer

Less Commonly Used:

Plain Myelography -

supplanted by CT myelography

Discography -

contrast injection into disk to assess for disk source of pain

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L-Spine Plain Films

Pros:

Fast, no contraindications Good for evaluating bony

structures

Trauma

Bony degeneration Spine alignment Cons:

Poor soft tissue discrimination Frequently will need CT/MRI

anyway

Radiation exposure

Image courtesy Dr. Kleefield, BIDMC

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CT and CT Myelography

Pros:

Excellent resolution of bony

anatomy

Trauma eval

Degenerative bony changes

Good for visualizing calcifications

and gas

Myelography: useful for LBP eval

when MRI is contraindicated

Cons:

Poor differentiation of soft tissues

within the spine

Radiation exposure

Myelography: invasive procedure

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Magnetic Resonance Imaging (MRI)

Pros:

Excellent soft tissue discrimination No radiation exposure

Most sensitive modality for evaluating

the spine

Cons:

Less sensitive for evaluating bony

anatomy and calcifications

Contraindicated for patients with

metal devices, etc.

Expensive

Image from PACS, BIDMC

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Simplified LBP Diagnostic Algorithim

Red Flags?

Conservative management, re- evaluate in 4 weeks Concerned about tumor, infection, or acute neurologic deficits? YES

MRI

Trauma

CT

and/or

Plain Films

Subacute neurologic symptoms? (i.e sciatica) YES

MRI

NO

Re-eval in 4-6 weeks Improvement?

MRI

YES

No further evaluation

NO

OR

NO

Adapted from Stern, SD, Cifu AS and Altkorn D, From Symptom to Diagnosis, McGraw-Hill: NY, 2006 and Lieberman, G Primary

Care Radiology:Radiologic assessment of low back pain, http://eradiology.bidmc.harvard.edu/primarycare/index.html Accessed

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Lumbar Spine: Sagittal Anatomy

L5 L4 L3 L2 L1 T12 Ligamentum flavum Note thickness Spinal canal

Note the width and amount of CSF Vertebral disk

Note central high T2 signal (NP) and low peripheral signal (AF)

Normal Lumbar Spine MRI Sagittal T2

Schematic images from Drake, Vogl and Mitchell, Gray’s Anatomy for Students, New York: Elsevier, 2005. MRI Image from PACS, BIDMC

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Lumbar Spine: Bone and Joint Anatomy

Images from Drake, Vogl and Mitchell, Gray’s Anatomy for Students, New York: Elsevier, 2005.

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Lumbar Spine: Axial Anatomy

Ligamentum flavum - Note the thickness here

Facet joint - Note how the joint surfaces align and the thin layer of high signal fluid between layers of low signal cartilage

Vertebral disk - Note the clean, concave margin of the annulus fibrosus (AF) next to the dura of the spinal canal. Nucleus pulposus = NP.

Neural foramina - This is an important area because the nerve roots exit here; note the space between the vertebral body (VB) and the facet joints here

Psoas

Paraspinal

NP

AF

Image from PACS, BIDMC Image courtesy of Dr. Kleefield _{Lumbar Spine MRI Axial T2}

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Due to her neurologic

symptoms and lack of

response to pain control Ms. S

had an MRI of her lumbar

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Ms. S: Extradural Masses and Spinal Stenosis on MRI

L5 L4 L3 L2 L1 T12

Normal

Findings

Spinal canal stenosis from L2-L5 due to extradural masses

Protruding low signal masses in posterior spinal canal L2-L5

Disks - Low signal

intensity from L2-L5 in addition to extension of disk into the spinal canal

Vertebrae - Posterior displacement of the L4 vertebrae

Ms. S

*

Images from PACS, BIDMC

Lumbar Spine MRI Sagittal T2 MRI Sagittal T2

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Differential Diagnosis: Extradural Mass

Degenerative Disk herniation Spinal stenosis Ligament ossification Synovial cyst Neoplastic Primary vertebral tumor Others: meningioma, neurogenic tumor Lymphoma Metastasis Infection Osteomyelitis Epidural abscess Trauma Epidural scar Iatrogenic Hematoma Fracture fragment Others Lipomatosis Paget’s disease Extramedullary hematopoesis Amyloidosis Granulomatous diseases

Adapted from: Reeder, M. Gamuts in Radiology: Fourth Edition. Springer 2003.

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Ms. S: Facet Arthropathy on MRI

Low signal mass in posterior spinal column

Spinal canal - marked reduction of CSF signal and compression of canal Facet joint arthropathy - osteophyte formation and distortion of joint alignment

MRI Axial T2 L4 vertebral body

*

PACS, BIDMC PACS, BIDMC Psoas Paraspinal NP AF MRI Axial T2 Normal Ms. S PACS, BIDMC

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Ms. S: Disk Bulge on MRI

Disk - Bulging of disk beyond margin of L4 vertebrae

Facet joint arthropathy - osteophyte formation and distortion of joint alignment MRI Axial T2 L3-L4 disk Psoas Paraspinal muscles Psoas Paraspinal NP AF MRI Axial T2 PACS, BIDMC Normal Ms. S PACS, BIDMC

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Ms. S’s Diagnosis: Degenerative Spinal Stenosis

Most likely:

degenerative spinal stenosis

Broad radiological differential

However, characteristic set of findings present

Osteophytes + misalignment: facet joint arthropathy

Low signal posterior masses: ligamentum flavum hypertrophy Disc extension into canal: disc bulge

Posterior vertebrae displacement: spondylolisthesis

Narrowed by history

Chronic nature of pain

Relief with sitting (neurogenic claudication) Advanced age

No other red flags: no evidence of infection, tumor, trauma

Neurological signs possibly consistent with stenosis

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Let’s discuss in more detail

the degenerative spine

disease found in Ms. S’s

imaging

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Facet joint arthropathy and ligamentum

flavum hypertrophy

Degenerative change

in facet joints can be

due to:

Osteoarthritis

Disk degeneration

Ligamentum flavum

hypertrophy

Due to vertebral

instability

Joint changes only

present in a few

percent of

asymptomatic patients

Image from Katz and Harris NEJM 2008

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Companion Patient #1: Facet joint arthropathy

PACS, BIDMC

Hypertrophic bone formation

(CT>MRI)

Joint space narrowing

Associated:

ligamentum flavum hypertrophy

Not seen here: subchondral sclerosis (CT>MRI)

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Axial T2 MRI Axial T2 MRI

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Disk Herniation

Many asymptomatic individuals have evidence

of disk herniation

Often spontaneously regresses

If herniation is symptomatic, results in symptoms

in nerve root inferior to level of herniation

i.e L3-L4 herniation --> L4 radiculopathy

Different types of herniation

Disk Bulge (technically not herniation), Protrusion and

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Ms. S: Disk Bulge

Circumferential

increase in

diameter without

annulus rupture

(not a true

herniation)

PACS, BIDMC Ms. S Axial T2 MRI

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Companion Patient #2: Disk Protrusion

Focal bulge

without complete

annulus rupture

Companion Patient #2

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Companion Patient #3: Disk Extrusion

Nucleus pulposus

ruptures through

annulus fibrosus

and extends into

epidural space

Companion Patient #3

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Spondylolisthesis

Spondylolisthesis = slippage of vertebrae

anteriorly or posteriorly

Can be caused by congenital factors,

degenerative disease, trauma, or systemic

disease

Severe displacement result in radiculopathy

by compression or stretch

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Companion Patient #4: Spondylolisthesis

L5 L4 L3 L2 L1 T12

Two examples of posterior spondylolisthesis

Images courtesy Dr. Kleefield, BIDMC and PACS, BIDMC

Ms. S Companion Patient #4

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Conclusions

Ms. S’s continued symptoms are consistent with

an L5 radiculopathy

However, her imaging is not consistent with this

She has more severe degeneration elsewhere

What can be done?

Surgery can be considered

Continued pain management

Alternative therapies: acupuncture, exercise

Sometimes imaging can confuse the clinical

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Acknowledgements

Dr. Gillian Lieberman - for her help,

encouragement and this opportunity

Dr. Alice Fisher - for guidance

Dr. Jonathan Kleefield - for many images and

encouragement

Maria Levantakis - making everything happen

Larry Barbaras - webmaster

Dr. Gillian Lieberman - for her help,

encouragement and this opportunity

Dr. Alice Fisher - for guidance

Dr. Jonathan Kleefield - for many images and

encouragement

Maria Levantakis - making everything happen

Larry Barbaras - webmaster

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References

(1) Carragee, EJ Persistent Low Back Pain, NEJM 2005 352:18, 1891-8.

(2) Katz JN and Harris, MB. Lumbar Spinal Stenosis, NEJM 2008 358:818-25.

(3) Modic MT and Ross JS, Lumbar Degenerative Disk Disease, Radiology 2007 245:

43-61.

(4) Wilson JF, In The Clinic: Low Back Pain. Ann Internal Medicine 2008:

148(9):ITC5-1-ITC5-16.

(5) Rumboldt Z, Degenerative Disorders of the Spine, Semin Roentgenology 2006

327-361.

(6) Reeder, M. Gamuts in Radiology: Fourth Edition. Springer 2003.

(7) Weissleder, R et al Primer of Diagnostic Imaging: Third Edition Philadelphia:

Mosby, 2003.

(8) Stern, SD, Cifu AS and Altkorn D, From Symptom to Diagnosis, McGraw-Hill: NY,

2006.

(9) Lieberman, G Primary Care Radiology:Radiologic assessment of low back pain,

Degenerative Lumbar Spine Disease