腰椎退行性病变的影像学诊断

Degenerative Lumbar Spine Disease Michael Barnett, HMS III Core Radiology Clerkship BIDMC PCE Beth Israel DeaconessBeth Israel Deaconess HarvardHarvard Medical CenterMedical Center MedicalMedical A Member of A Member of CaregroupCaregroup SchoolSchool 2 OverviewOverview „ Patient Presentation: Ms. S „ Clinical Work-up of Low Back Pain „ Menu of Radiological Tests „ Lumbar Spine Anatomy „ Patient Imaging: Ms. S „ Discussion of Degenerative Spine Disease 3 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 steroid injections failed to provide relief 4 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 5 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 Wilson JF, In The Clinic: Low Back Pain. Ann Internal Medicine 2008: 148(9):ITC5-1-ITC5-16 6 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 Carragee, EJ Persistent Low Back Pain, NEJM 2005 352:18, 1891-8. 7 However, it is important to be aware of red flags which necessitate imaging … 8 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 ƒ Fever, chills ƒ Recent skin or urinary infection ƒ Immunosuppresion ƒ IVDU ƒ Recent spine surgery Neurologic ƒ Sciatica ƒ New onset urinary/fecal incontinence ƒ Abnormal neurologic exam: motor, sensory, reflexes Tumor ƒ Age >50 ƒ History of previous cancer ƒ Unexplained weight loss 9 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 „ Spinal Angiogram - assess vasculature of spine 10 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 Lumbar spine plain X-ray film 11 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 Image courtesy Dr. Kleefield, BIDMC Lumbar Spine CT 12 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 Lumbar Spine MRI T2 13 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 10/17/2008 14 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 15 Lumbar Spine: Bone and Joint Anatomy Images from Drake, Vogl and Mitchell, Gray’s Anatomy for Students, New York: Elsevier, 2005. aka facet joint 16 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, BIDMCImage courtesy of Dr. Kleefield Lumbar Spine MRI Axial T2 Due to her neurologic symptoms and lack of response to pain control Ms. S had an MRI of her lumbar spine … 18 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 vertebraeMs. S * * Images from PACS, BIDMC Lumbar Spine MRI Sagittal T2MRI Sagittal T2 19 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. Image from PACS, BIDMC 20 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 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 22 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 present at L4-L5, but most severe stenosis is L3-L4 Let’s discuss in more detail the degenerative spine disease found in Ms. S’s imaging 24 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 Katz JN and Harris, MB. Lumbar Spinal Stenosis, NEJM 2008 358:818-25 25 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) Image courtesy Dr. Kleefield, BIDMC * * Axial T2 MRIAxial T2 MRI Companion Patient #1 Ms. S 26 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 Extrusion 27 Ms. S: Disk Bulge Circumferential increase in diameter without annulus rupture (not a true herniation) PACS, BIDMC Ms. S Axial T2 MRI 28 Companion Patient #2: Disk Protrusion Focal bulge without complete annulus rupture Image courtesy Dr. Kleefield, BIDMC Companion Patient #2 Axial T2 MRI 29 Companion Patient #3: Disk Extrusion Nucleus pulposus ruptures through annulus fibrosus and extends into epidural space Image courtesy Dr. Kleefield, BIDMC Companion Patient #3 Sagittal T2 MRI 30 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 „ Also contributes to spinal canal stenosis 31 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 Sagittal T2 MRI Sagittal CT Lumbar Spine 32 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 picture, especially with low back pain 33 AcknowledgementsAcknowledgements „ 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 34 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, http://eradiology.bidmc.harvard.edu/primarycare/index.html Accessed 10/17/2008 Degenerative Lumbar Spine Disease Overview Our Patient, Ms. S Clinical DDx Low Back Pain Low Back Pain Low Back Pain Work-Up However, it is important to be aware of red flags which necessitate imaging … Red Flags with LBP Menu of Tests for Low Back Pain Assessment L-Spine Plain Films CT and CT Myelography Magnetic Resonance Imaging (MRI) Simplified LBP Diagnostic Algorithim Lumbar Spine: Sagittal Anatomy Lumbar Spine: Bone and Joint Anatomy Lumbar Spine: Axial Anatomy Due to her neurologic symptoms and lack of response to pain control Ms. S had an MRI of her lumbar spine … Ms. S: Extradural Masses and Spinal Stenosis on MRI Differential Diagnosis: Extradural Mass Ms. S: Facet Arthropathy on MRI Ms. S: Disk Bulge on MRI Ms. S’s Diagnosis: Degenerative Spinal Stenosis Let’s discuss in more detail the degenerative spine disease found in Ms. S’s imaging Facet joint arthropathy and ligamentum flavum hypertrophy Companion Patient #1: Facet joint arthropathy Disk Herniation Ms. S: Disk Bulge Companion Patient #2: Disk Protrusion Companion Patient #3: Disk Extrusion Spondylolisthesis Companion Patient #4: Spondylolisthesis Conclusions Acknowledgements References