1. Spinal Stenosis/Neurogenic Claudication
Chris Dowding
Half Day Feb

2. Low Back Pain
About ¾ of all individuals will experience low back pain at some time in their lives; usually, it resolves in a matter of weeks.
Low back pain is the leading cause of disability in people younger than 50 years of age.
LBP - M=F
Peak incidence between 35 and 50 years of age
Primary causes of low back pain
Muscle strain or ligament sprain
Facet joint arthropathy
Discogenic pain or Annular tears
Spondylolisthesis
Spinal stenosis

3. Anatomy

4. What is Spinal Stenosis?
First described by Verbiest 1954
7 patients with syndrome of the following:
Lumbar canal narrowing
Neurogenic spinal claudication
Radicular pain
Motor weakness in lower limb

5. Definition Spinal Stenosis Primary subtypes
Narrowing of the spinal canal, resulting in a clinical syndrome of leg dominant pain
Primary subtypes
Central canal stenosis
Subarticular stenosis (area under facet joints)
Neural foramina stenosis
Symptoms are caused by compression of the nerve roots
Results in neurogenic claudication

6. Definition Neurogenic claudication
Discomfort or pain that radiates from the spinal area into the buttocks and frequently into thigh and lower leg

7. Pattern 4 Leg dominant pain
Pain is brought on by activity and relieved by rest in flexion.
Pain is always intermittent. Neurological symptoms usually absent at rest.
Vascular – worse with walking, relief with rest, poor or absent pulses
Neurogenic – worse with walking or standing, relief with sitting or flexion, physical exam normal, pulses present

8. Claudication Pattern 1 Pattern 2 Pattern 3 Pattern 4 Region Back Leg
Worse with:
Flexion
Extension
Movement
Relief with:
Fast:Extension
Slow: Nil
Usually flexion
Fast: Posturing
Timing:
Constant or Intermittent
Intermittent
Constant
Neuro:
Normal
Present
Generator:
Degenerative disc; soft tissues
Facet arthritis; soft tissues
Disc herniation
Spinal stenosis
Region – location where pain is at its worst. Doesn’t mean that pain is not present elsewhere as well.
Again, reminder that this classification system is based on pattern recognition and not necessarily anatomic site or pathologic process. The overwhelming majority of patients with Pattern 1 and Pattern 2 back pain are not surgical candidates. If physical rehab can improve or get rid of pain, the specific anatomic pain generator does not matter.
With pattern 3 and pattern 4, surgical management becomes more likely and identification of an anatomic pain generator becomes very important.

9. Claudication Symptoms/Findings Neurogenic Claudication
Vascular Claudication
Pain
Dermatomal
Muscle grip
Sensory Loss
Stocking
Worse with:
Variable exercise, standing
Fixed amount of exercise
Relief with rest:
Slow, positional
Immediate
Foot pallor (elevation)
None
Marked
Pulses
Normal
Decreased/absent

10. Claudication

11. Etiology Spinal Stenosis Narrowing of spinal canal due to:
Degenerative
(most common)
Developmental
Congenital disorders
Post traumatic
Steroids
Post-surgical
Certain disorders

12. Degenerative Stenosis
Narrowing is secondary to arthritis
Typically following order
Disc degeneration
Facet osteoarthritis
Flavum hypertrophy
Symptoms develop around 60 yo

13. Intervertebral Joints
Two Components:
1. Outer rim of fibrocartilage called the annulus fibrosus (attaches to cartilaginous end plate)
Connects vertebral bodies in a fibrocartilaginous joint (no capsule, little motion)
2. Facet (Zygapophyseal) joints

14. Intervertebral Disks Collagen, water, Proteoglycans Fibrocartilaginous
Annulus Fibrosus
Obliquely oriented collagen
Type I collagen
Outer rim contains free nerve endings
Central Nucleus Pulposus
88+% water, high polysaccharide content
No blood vessels or nerves
Type II collagen
Structure deforms when pressure is put on vertebral column as in weight bearing
Acts as a shock absorber
Annulus totally encloses the nucleus and keeps it under constant pressure
As you get older, the H2O content decreases and the nucleus becomes more fibrocartilaginous, therefore less easily deformable and more easily damaged
Nucleus, when under extreme pressure, can herniate or extrude from the disc in a posterior or posterior-lateral direction
Usually occurs in cervical or lumbar region
Nucleus can put pressure on spinal nerve causing refereed symptoms (motor and sensory)
Can cause pressure on cord itself if true posterior

15. Intervertebral Disks Function Disk is avascular. As Disks ages
spinal motion and stability.
Disk is avascular.
Nutrients fluid via diffusion through pores in the hyaline cartilage end plates
As Disks ages
Decreased water content, increased collagen.

16. Disk Degeneration Begins roughly third decade of life.
Characterized by a decline in proteoglycan concentration with resultant loss of hydration and a decreased number of viable cells
L4-5 and L5-S1 are the disks that typically degenerate first

17. Degenerative Disks
Disk height decreases, resulting in alteration of the segmental spinal biomechanics
Increasing wear on facet joints
The precise cause(s) of disk degeneration are unclear, and there are several potential contributors
Comorbidities like diabetes, vascular insufficiency, and smoking are potentially associated with disk degeneration
There appears to be a genetic component to disk degeneration

18. Degenerative Stenosis
Loss of disc height
 Infolding of flavum
 Increased stress across facets
 Facet OA and hypertrophy
 Osteophytes and capsule thickening
 Cysts

20. Degenerative Stenosis
Spondylolithesis (+/- spondylolysis)
Can result in stenosis
Back pain is primary symptom
Neurogenic claudication is secondary

21. Developmental Stenosis
Narrowing of canal due to growth disturbance of posterior elements
Congenitally short pedicles
Often present in 20’s

22. Presentation Constellation of symptoms Leg pain Difficulty ambulating
Comfortable sitting
Pain with prolonged walking
Neurologic deficits

23. History Age Pain Aggravating or relieving factors? Previous therapy?
Location
Timing
Characteristics
Aggravating or relieving factors?
Previous therapy?
PMHx
Social History/Occupation
Meds/Allergies
Functional Inquiry
How far can you walk?
Can they bike?
The two most important questions on history are: Back dominant vs Leg dominant; Constant vs intermittent
Characteristics of pain – dull, sharp, electric, shooting. Numbness, tingling.
Relief with certain posturing

24. Red Flags Night sweats Saddle anaesthesia Fever Sexual dysfunction
Weight loss
Age > 60
Bowel/Bladder
History of IVDU
History of cancer
Chronic infections
Immunosuppression
Rest/night pain
Pain not relieved when patient lies down.

25. Physical Exam Vitals Palpate Inspect Spinous processes Gait
Paraspinal muscles
Leg length
Greater trochanters
Trendelenburg test
Spinal alignment

26. Physical Exam ROM Neuro
Spine flexion, extension, rotation, lateral bend
Hip flexion, extension, rotation
Pain with etxension, relieved by flexion
Neuro
Strength
Sensation
Reflexes
Half of patients with symptomatic stenosis have motor or sensory deficits
Usually mild

27. Neurologic Examination

28. Special Tests Romberg maneuver Patient stands with eyes closed
Look for unsteadiness, wide based stance
Indicates damaged proprioception

29. Imaging Lumbar x-rays CT/MRI +/- spondylolithesis
Extent of disc narrowing
Foramina osteophytes
CT/MRI
Can illustrate reductions in cross sectional diameter of central canal or foramina
Useful for pre-op planning or assessing candidacy for epidural injections
Large number of people may have radiologic findings but are asymptomatic
SLR defined as the reproduction of sciatica symptoms when the hip is flexed passively with a straight leg between 30 and 70 degrees.
The diagnostic odds ratio remains low because surgical patients WITHOUT a disc herniation are likely to have a positive SLR.
Straight leg raising, by itself, can produce pain from a variety of sources, including myogenic pain, ischialburisitis, annular tear, and hamstring tightness, as well as herniated disc.

30. Location of stenosis Centrally Lateral recess & neural foramina
Degeneration of
Disk
Facets (hypertrophy)
Synovial cysts
Joint capsule
Thickening of ligamentum flavum
Osteophytes

31. Identifying the cause Differential is broad
Some non-spinal causes to keep in mind
Vascular claudication
Hip arthritis
Diabetes (peripheral neuropathy)

32. Vascular Claudication
Cramping/tightness in calf
PVD (skin ulcers, trophic changes)
Diminished pulses
Relieved by cessation of activity
Versus neurogenic (flexion or sitting down)
Capable of activity while flexed
shopping cart
Cycling
walking uphill

33. Hip Arthritis Groin pain Referred pain in thigh
increased with activity
Internal rotation diminished
XR - OA

34. Diabetes
Glove & stocking distribution
Not affected by activity level

35. Conservative Management
Physical therapy
Abdominal strengthening
Biking
Brace/corset
Slight lumbar flexion
Limit hours worn per day
Avoid atrophy
Pain pyramid
Tylenol
NSAIDS
Narcotics

36. Conservative Management
Epidural injections
Theory is that compression of nerve roots causes inflammation and thus symptoms
Cortocosteroids to reduce inflammation
Evidence is not convincing one way or another
Although this practice is increasing

37. Natural History? Natural course of disease
Pain / function of patients with lumbar stenosis
remains unchanged in majority patients
After one year of non-op management the majority of patients will be neither worse nor better
Rapid decline uncommon
Therefore prophylactic treatment non indicated
Improvement is also uncommon
If patient is miserable at baseline, non-op management may not be appropriate

38. Surgical indications Progressive neurologic deficit Intractable pain
Persistent impairment and functional limitation
Confirmation by imaging
LBP is not alleviated with surgery!

39. Lumbar Stenosis: So when should we operate?
Goals of surgery
Decompress central canal and neural foramina
Options
Laminectomy **
Partial facetectomy **
Lumbar arthrodesis
+/- Instrumentation
Interspinous distraction
MIS

40. Algorithm?
Edward N. Hanley Jr., MD, Spinal Stenosis, Charlotte

41. Treatment – Spinal Stenosis
Maine lumbar spine study
119 patients
67 treated surgically
52 treated nonsurgically
After 4 years 70% of surgically treated and 52% of nonsurgically treated reported that their predominant pain was better.
Satisfaction 63% of surgically treated and 42% of nonsurgically treated.
Atlas et al. Spine
Over time, relative benefits of surgery declined but still remained superior to nonsurgical management
Better, same or worse rating scale.

42. Malmivaara 2007 Design RCT 4-university hospitals 94 patients Surgical
Laminectomy 10 patients also had transpedicular fusion
Outcome
Oswestry Disability Index (0-100)
Intensity of pain (0-10)
Walking ability – self-reported
6,12&24 months

43. Malmivaara 2007 Inclusion Criteria
Back pain radiation to lower limb/buttock
Fatigue loss sensation aggravated by walking
Persistent pain without progressive neurologic dysfunction
SAC (sagital) < 10 mm
Duration of symptoms > 6 months
Signs & symptoms correspond to segmental radiographs
Severity of disease to justify surgical/non- surgical rx

44. Malmivaara 2007 Exclusion Severe LSS intractible pain
Progressive neurologic dysfunction
Mild LSS with clinical signs feeble enough to exclude surgical treatment
Spondylolysis and spondylolytic disease
Earlier back operation due to stenosis
Herniated disc during last 12 months
Another spinal disorder
Intermittent claudication due to PVD
Severe OA of L/E
Neurologic disease with impaired function of L/E
Psych
Alcoholic

45. Malmivaara 2007 Randomization:
Central office computer generated blocks variable size for each hospital
Physician phoned central office after baseline exam, questionnaire completed

46. Malmivaara 2007 Intervention Surgical group Segmental decompression
Facetectomy
Instability treated at surgeon discretion
Fusion of lumbar spine +/- instrumentation
Degenerative listhesis warranting procedure
Brochure for nature of disease, symptoms and activities
Non-operative group
Physiatrist followed throughout
Physiotherapist followed
Exercises

47. Malmivaara 2007 Walking ability Reported & measured
No significant difference between 2 groups

48. Malmivaara 2007 Conclusion Issues
Those undergoing surgery reported greater improvement over non-operative treatment
Benefit diminished over time
Issues
Longer f/u needed
Surgical treatment differed
Selected bias from exclusion criteria
Screened for those who may benefit from surgery

49. Weinstein 2008
SPORT Trial
“Surgical versus Nonsurgical Therapy for Lumbar Spinal Stenosis”
Inclusion
12 weeks of symptoms typical to stenosis
Exclusion
Spondylolithesis

50. Weinstein 2008 2 cohorts Outcomes A) randomization B) observational
Op vs non-op
B) observational
Elective op vs. elective non-op
Outcomes
Bodily pain and physical function
SF-36
Modified Oswestry disability index
6 weeks, 3 months, 6 months, 1 year, 2 years

51. Weinstein 2008 Randomized cohort Interventions
En bloc at 13 institutions
289 patients
Interventions
Op:
“Standard posterior decompressive laminectomy:
Non Op:
At least physical therapy, education or counseling
NSAIDs if tolerated

52. Weinstein 2008 Results As-treated ITT
Significant advantage of operative management at 6 weeks, peaked at 6 months and lasted for 2 years
Significant across all outcomes
ITT
Significant difference in pain scale favouring operative management
No difference in physical function rating or Oswestry disability scale

53. Weinstein 2008 Issues: Significant cross-over:
“At 2 years, 67% of patients who were randomly assigned to surgery had undergone surgery, whereas 43% of those who were randomly assigned to receive nonsurgical care had also undergone surgery.”
Excludes spondylolithesis
Doesn’t tell us anything about to fuse or not to fuse

54. Claudication Spinal Stenosis Claudication and Spinal Stenosis Non-op
Educate, Analgesia, Exercise (Core, Aerobic), Physio, Lifestyle, Advise CES
Cauda Equina Syndrome
(Acute: Surgery as a P2, Chronic: Surgery Within Weeks)
Leg Dominant
Signif. Back Pain
? No Surgery
Pt. Choice
Medical Comorbidity
Unsure of Diagnosis
Willing to wait
Progressive Weakness
No Instability
Instability
No Instability
(Surgery as P3 to Within Weeks)
Degen. Spondylolisthesis, Lat. Listhesis, Scoliosis
Posterior Decompression (Laminectomy, Foraminotomy)
Epidural
(Note: Facet Sparing, If No Fusion)
Predictors of Good Surgical Outcome
Relative Indication
Assess Additional Fusion Levels
Leg Dominant Pain
Not Foraminal
? Degree of Stenosis
? # of Levels
? No scoliosis
No WSIB / Disability
No Blame
No Hysteria
No Comorbidity
< 6 months pain
Baseline fitness
? Surgery for pain as opposed to for neuro deficit
Bone Scan, MRI, Discogram
Fusion (All Decompressed Levels + ? Additional Levels)
Non-instrumented, Instrumented (Pedicle Screws, TLIF, PLIF)
From Spine rounds Civic
Last Updated: Oct 18, 2007

55. Refs
Atlas SJ, Delitto A. Spinal stenosis: surgical versus nonsurgical treatment. Clin Orthop Relat Res 2006; 443:198.
Katz JN, Harris MB. Clinical practice. Lumbar spinal stenosis. N Engl J Med 2008; 358:818.
Malmivaara A, Slätis P, Heliövaara M, et al. Surgical or nonoperative treatment for lumbar spinal stenosis? A randomized controlled trial. Spine 2007;32:1-8.
Weinstein JN, Tosteson TD, Lurie JD, et al. Surgical versus nonsurgical therapy for lumbar spinal stenosis. N Engl J Med 2008;358: