Diagnosing Low Back Pain

Eden Wheeler, M.D.

Physical Medicine and Rehabilitation Rockhill Orthopaedics, P.C.

1

I. History:

2

• •

Mechanism of injury Associated symptoms:

• • • • Bladder / bowel function Fevers / chills Sleep disturbance Numbness / tingling • • • •

Prior injuries, treatment and outcomes Medications Family history Social history:

• • • • Vocational Education Tobacco / ETOH / Illicit drugs Function: ADLs & Mobility •

Litigation

3

• • • • • • • •

Pain Specifics:

Quality:

sharp, dull, shooting, burning, etc.

Location / Distribution:

• •

Radicular: Radiating:

Dermatomal distribution, dysesthesias Nondermatomal

Onset:

• •

Gradual:

DDD

Acute:

Disc abnormality, strain, compression fractures

Severity / Intensity Frequency: Constant vs. Intermittent Duration Exacerbating and Alleviating Factors Time of Day:

If nocturnal, consider malignancy 4

• • • • • •

Red Flags:

Significant trauma history, or minor in older adults Nocturnal pain in supine position with history of cancer Bladder or bowel incontinence or dysfunction Constitutional symptoms:

• Fever / chills • • Weight loss Lymph node enlargement

Risk factors for spinal infection

• • • Recent infection IV drug use Immunosuppression

Major motor weakness

5

II. Examination:

6

A. Physical:

• • •

Posture:

• •

Splinting Body language Gait:

• • •

Antalgia Heel / Toe pattern Trendelenberg Musculoskeletal:

• • • •

ROM Leg length Vascular Atrophy

7

•

Abdomen:

•

Presence of masses

•

Back:

• • • •

Inspection Palpation ROM Scoliosis

•

Neurological:

• • •

Sensation Motor DTRs

•

Rectal if indicated:

•

Evaluation of sphincter tone

8

•

B. Symptom Magnification Examination:

Waddell signs: Presence of nonorganic signs suggesting symptom magnification and psychological distress

– – – – – Superficial or nonanatomic distribution of tenderness Nonanatomic or regional disturbance of motor or sensory impairment Inconsistency on positional SLR Inappropriate/excessive verbalization of pain or gesturing Pain with axial loading or rotation of spine •

Give-away weakness: Inconsistent effort on manual motor testing with “ratcheting” rather than smooth resistance

9

C. Pathological Examination:

•

Spurling’s maneuver:

Lateral rotation and extension of spine resulting in neuroforaminal narrowing and nerve root encroachment, clinically reproducing extremity pain, usually in dermatomal distribution •

Straight-leg raise (SLR):

Elevation of lower extremity, seated or standing, resulting in neural tension at S1 nerve root with extremity pain •

Patrick’s maneuver:

Crossed leg with unilateral pain indicative of sacro-iliac (SI) joint dysfunction •

Femoral stretch:

Hip extension stretch with heel pushed to buttock in lateral supine or prone position resulting in anterior thigh pain 10

III. Low Back Pain:

11

• • • • •

A. Epidemiology:

Incidence of LBP:

• •

60-90 % 5 %

lifetime incidence annual incidence

90 % of cases of LBP resolve without treatment within 6-12 weeks 40-50 % LBP cases resolve without treatment in 1 week 75 % of cases with nerve root involvement can resolve in 6 months LBP and lumbar surgery are:

• • •

2nd 5th 3rd

and

3rd

highest reasons for physician visits leading cause for hospitalization leading cause for surgery 12

B. Disability:

•

Age and LBP:

• •

Leading cause of disability of adults < 45 years old Third cause of disability in those > 45 years old

•

Prevalence rate:

•

Increased 140 % from 1970 to 1981 with only 125 % population growth

•

Nearly 5 million people in the U.S. are on disability for LBP

13

C. Lifetime Return to Work:

•

Success of

less than 50 %

than 6 months if off work greater

•

25 %

success rate if off work greater than 1 year

•

Nearly 0 %

success if return to work has not occurred in 2 years

14

D. Occupational Risk Factors:

• • • • • •

Low job satisfaction Monotonous or repetitious work Educational level Adverse employer-employee relations Recent employment Frequent lifting

• Especially exceeding 25 pounds • Utilization of poor body mechanics in technique 15

E. Differential Diagnoses:

• • • • • • • •

Lumbar strain Disc bulge / protrusion / extrusion producing radiculopathy Degenerative disc disease Spinal stenosis Spondyloarthropathy Spondylosis Spondylolisthesis Sacro-iliac dysfunction

16

•

F. Diagnostic Tools:

1. Laboratory:

• • • Performed primarily to screen for other disease etiologies • Infection • Cancer • Spondyloarthropathies No evidence to support value in first 7 weeks unless with red flags Specifics: • WBC • ESR or CRP • HLA-B27 • Tumor markers: Kidney Breast Lung Thyroid Prostate 17

•

2. Radiographs:

• • • Pre-existing DJD is most common diagnosis Usually 3 views adequate with obliques only if equivocal findings Indications: • History of trauma with continued pain • Less than 20 years or greater than 55 years with severe or persistent pain • Noted spinal deformity on exam • Signs / symptoms suggestive of spondyloarthropathy • Suspicion for infection or tumor 18

• •

3. EMG / NCV ( Electrodiagnostics):

• Can demonstrate radiculopathy or peripheral nerve entrapment, but may not be positive in the extremities for the first 3-6 weeks and paraspinals for the first 2 weeks • Would not be appropriate in clinically obvious radiculopathy

4. Bone scan:

• • Very sensitive but nonspecific Useful for: • • • Malignancy screening Detection for early infection Detection for early or occult fracture 19

•

5. Myelogram:

• Procedure of injecting contrast material into the spinal canal with imaging via plain radiographs versus CT • In past, considered the gold standard for evaluation of the spinal canal and neurological compression • With potential complications, as well as advent of MRI and CT, is less utilized: • More common: Headache, nausea / vomiting • Less common: Seizure, pain, neurological change, anaphylaxis • • Myelogram alone is rarely indicated Hitselberger study 1968 Journal of Neurosurgery: •

24 %

of asymptomatic subjects with defects 20

•

6. CT with myelogram:

• • Can demonstrate much better anatomical detail than myelogram alone Utilized for: • Demonstrating anatomical detail in multi-level disease in pre operative state • Determining nerve root compression etiology of disc versus osteophyte • Surgical screening tool if equivocal MRI or CT 21

•

7. CT:

• • Best for bony changes of spinal or foraminal stenosis Also best for bony detail to determine: • Fracture • DJD • Malignancy • SW Wiesel study 1984 Spine: •

36 %

of asymptomatic subjects had “HNP” at L4-L5 and L5-S1 levels 22

•

8. Discography (Diagnostic disc injection):

• Less utilized as initial diagnostic tool due to high incidence of false positives as well as advent of MRI • Utilizations: • Diagnose internal disc derangement with normal MRI / myelo • Determine symptomatic level in multi-level disease • Criteria for response: • Volume of contrast material accepted by the disc, with normals of 0.5 to 1.5 cc • Resistance of disc to injection • Production of pain---

MOST SIGNIFICANT

• Usually followed by CT to evaluate internal architecture, but also may utilize MRI • As outcome predictor (

Coulhoun study 1988 JBJS

): • •

89 %

of those with pain response received benefit from surgery

52 %

of those with structural change received surgical benefit 23

•

9. MRI:

•

Best diagnostic tool for:

• Soft tissue abnormalities: • Infection • Bone marrow changes • Spinal canal and neural foraminal contents • Emergent screening: • Cauda equina syndrome • Spinal cored injury • Vascular occlusion • Radiculopathy • • • Benign vs. malignant compression fractures Osteomyelitis evaluation Evaluation with prior spinal surgery 24

• • •

Has essentially replaced CT and myelograms for initial evaluations Boden study 1990 JBJS:

•

20 %

of asymptomatic population less than 60 years with “HNP” •

36 %

of asymptomatic population of 60 years

Jensen study 1995 NEJM:

•

52 %

of asymptomatic patients with disc bulge at one or more levels • •

27 % 1 %

of asymptomatic patients with disc protrusion of asymptomatic patients with disc extrusion 25

•

MRI with Gadolinium contrast:

• Gadolinium is contrast material allowing enhancement of intrathecal nerve roots • Utilization: • Assessment of post-operative spine---most frequent use • Identifying tumors / infection within / surrounding spinal cord • Diagnosis of radiculitis • Post-operatively can take 2-6 months for reduction of mass effect on posterior disc and anterior epidural soft tissues which can resemble pre-operative studies • Only indications in immediate post-operative period: • Hemorrhage • Disc infection 26

•

10. Psychological tools:

• Utilized in case scenarios where psychological or emotional overlay of pain is suspected • Symptom magnification • Grossly abnormal pain drawing • Non-responsive to conservative interventions but with essentially normal diagnostic studies • Includes: • Pain Assessment Report, which combines: • McGill Pain Questionnaire • Mooney Pain Drawing Test • MMPI • Middlesex Hospital Questionnaire • Cornell Medical Index • Eysenck Personality Inventory 27

• • • • • •

MRI Nomenclature:

(PER NASS)

Anular fissure:

transverse distribution Focal disruption of anular fibers in concentric, radial or

Disc bulge:

Circumferential

, diffuse, symmetric extension of anulus beyond the adjacent vertebral end plates by 3 or more mm, usually due to weakened or lax anular fibers

Disc protrusion:

Focal, asymmetric extension of disc segment beyond margin of vertebral end plates into the spinal canal with most of anular fibers intact

Disc extrusion:

Focal, asymmetric extension of disc segment and / or nucleus pulposis through the anular containment into the epidural space

Disc sequestration:

with migration into the canal Extruded disc segment that is detached from original

Disc degeneration:

Irreversible structural and histiological changes in nucleus seen on MRI T2WI images (commonly associated with bulge) 28

Specificity / Sensitivity

Diagnosis Disc “Herniation” Spinal Stenosis Test CT MRI CT Myelo CT MRI Myelogram Sensitivity 0.90

0.90

0.90

0.90

0.90

0.77

Specificity 0.70

0.70

0.70

0.80-0.95

0.75-0.95

0.70

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•

G. Treatment

Medications

• • NSAIDS Membrane stabilizers • TCA / Neurontin • re-establish sleep pain • reduce radicular dysesthesias • Muscle relaxers: • re-establish sleep patterns • more useful in myofascial/muscular pain • • • Narcotics: rarely indicated Steroids: more useful for radiculitis Non-narcotic analgesics: Ultram 30

• •

Physical therapy

• • • • • • • • Modalities electrical stimulation/TENS Postural education / body mechanics Massage / mobilization / myofascial release Stretching / body work Exercise / strengthening Traction Pre-conditioning / work-conditioning

Injections

• • • • • Epidural blocks Facet blocks Trigger point SNRB SI joint 31

•

Surgery:

• • • • Laminectomy Fusion Discectomy Percutaneous Lumbar Discectomy – – Success rate variable 50 -85 % Low rate of complications: • Infection • Peripheral nerve injury – Benefits: • Outpatient procedure • Minimal to no epidural scarring • No general anesthesia • Spine stability preservation • Decreased cost 32

• • •

Chemonucleolysis IDET:

Intradiscal Electrotherapy or Spine CATH

Alternative:

• Chiropractic: • Clinical studies show benefit only in first 3 weeks of symptoms • • Acupuncture Biofeedback 33

IV. Specific Disorder Considerations

34

•

A. Sacroiliitis:

History:

• • Trauma is very common Repetitive LS motion--lumbar rotation or axial loading • • No specific correlation with exacerbating activities Commonly have leg length discrepancy or condition contributing •

Biomechanics:

• Movement of the SIJ is involuntary, usually from muscle imbalances • • Can occur at multiple levels: lower extremities, hip, LS spine Motion is complex and not single-axis based 35

•

Differential Diagnosis: a. Fracture

• Traumatic • Insufficiency stress fractures: elderly patient with osteoporosis without history of trauma • Fatigue stress fractures: usually athletes / soldiers

b. Infection

• • Hematogenous spread with predisposing history Usually unilateral symptoms present

c. Degenerative joint disease d. Metabolic disease e. Referred pain

36

f. Seronegative spondyloarthropathies

• • • RA--usually not until late in course of disease Ankylosing spondylitis Psoriatic arthritis

g. Primary SI tumor

• Rare and usually synovial villoadenomas

h. Iatrogenic instability

• Via pelvic tumor resection or bone graft site

i. Osteitis condensans ilii

• Prevalence of

2.2 %,

primarily in multiparous women • Usually self-limiting and bilateral

j. Reactive disease

as sequellae of PID 37

•

Diagnostic Tools:

• X-rays: Up to 25 % of asymptomatic adults over 50 years can have abnormalities • MRI / CT: Only if looking for tumor • Bone scan: Good for fractures but less favorable for inflammation •

Treatment:

• • • • Medications: NSAIDS Physical therapy Correct limb discrepancy Injection: Fluoroscopy-guided vs. local • Surgical fusion: Few figures for efficacy 38

B. Cauda Equina Syndrome:

•

History:

• Sudden, partial or complete loss of voluntary bladder function due to massive disc impingement on spinal nerves • Can include loss of sensation as well as sphincter tone •

Treatment:

• Urgent decompression is

mandatory

for prevention of irreparable / irreversible bladder damage •

12 hours

is the maximum time prior to irreversible changes 39

•

C. DDD and Spondylosis:

Clinical:

• Up to 75 % of involvement of the spine occurs at 2 levels: L5-S1 and L4-L5 •

Possible

factors that contribute to development: – Changes with maturation in: • Nutrition • Disc chemistry • Hormones – Occupational forces • Progression of disc narrowing leads to degenerative changes of bony structures, especially posterior components, leading to spondylosis 40

•

Treatment:

• • • Medications Physical therapy Lifestyle changes: • Smoking cessation • Weight loss • Vocational changes • Injections: • Less helpful if pain is limited to central low back only • Surgery: • Laminectomy • Fusion 41

•

D. Spinal Stenosis:

Clinical:

• Results from narrowing of spinal canal and / or neural foramina (CONGENITAL OR DEGENERATIVE) • • Most common complaint is leg pain limiting walking

Neurogenic / Pseudoclaudication

= pain in lower extremities with gait • Relief can occur with: – stopping activity – sitting, stooping or bending forward • Common are complaints of weakness and numbness of extremities • Usually becomes symptomatic in 6th decade 42

• •

Diagnosis:

• CT and MRI may yield false-positive results, therefore EMG / NCV can be helpful to confirm diagnosis • Myelography also can be confirmatory and pre-surgical screening tool

Treatment:

• • • Medications Physical therapy TENS • • Epidural injections Surgical decompression laminectomy 43

E. “HNP”:

•

Clinical:

• Low back pain wit associated leg symptoms • • Positions can induce radicular symptoms Posterolateral disc pathology most common: • Area where anular fibers least protected by PLL • Greatest shear forces occur with forward or lateral bend • Central disc pathology: • Usually with LBP only without radicular symptoms, unless a large defect is present 44

•

Treatment:

• Conservative treatment: – Saul and Saul study 1989 Spine: •

> 90 %

success rate of symptom resolution with non-operative management – Bozzao study 1992 Radiology: • 69 patients with “HNP” studied longitudinally with MRI • 63 % with >30 % reduction with 48 % > 70 % reduction over time • • • • Medications Physical therapy Injections Surgery 45

F. Pars Interarticularis Defects:

•

Spondylolysis:

• • • Anatomic defect in the bony pars interarticularis within the lamina May uni- or bilateral Can be congenital or induced • Usually without clinical symptoms with incidental findings on radiographs 46

• •

Spondylolisthesis

• • Progression of spondylolysis with separation • Grades assigned I-IV for level of translation • Most common levels are L5-S1 (

70 %

) and L4-L5 (

25 %

) May be asymptomatic, but can result in • Spondylosis • DDD • Radiculopathy

Treatment:

• Medication • • • Physical Therapy Injections Surgery 47

V. Chronic Pain Issues

48

A. Pain Reinforcing Factors:

•

Secondary gain:

Support system allows passive / inactive role for patient via catering to needs and hence fostering dependency •

Environmental:

Inadequate opportunity or skills to compete in the professional community •

Physician knowledge deficit:

In areas of diagnosis and appropriate treatment, can prolong symptoms and validate pain behavior •

Worker’s compensation:

financial compensation or open claim may discourage desire for return work and impede recovery Laws have become counterproductive- •

Litigation:

Anticipation of large financial settlement can reinforce pain behavior and develop into learned pain behavior 49

B. Risk Factors for Delayed Recovery:

Occupational Psychosocial Medical

 

Job availability



Patient perception of work load Job dissatisfaction



Time off of work



Anger with “system”



History of narcotic or substance abuse

 

Disabled spouse Poor English proficiency



Poor fitness



History of prior injury

50

C. Discouraging Chronic Pain:

•

Requiring employer to accommodate restrictions to allow continued working during treatment and recovery

•

Rapid abjudication of disability and compensation claims

•

Physician education re: appropriate treatments and limiting use of potentially addictive medications

•

Ergonomic work environments

•

Patient education re: disease process and treatment options

51

•

D. Considerations of PM & R Treatment:

Physical therapy is initially usually one of modalities with progression into more active exercise

• • • • •

Pre-conditioning therapy is more functional with transition into Work Conditioning (Work Hardening) program Always consider return to work, whether modified duty with restrictions or limiting hours worked If patients poorly tolerate standard therapy, consider pool therapy intervention which allows elimination of gravity effects Functional Capacity Evaluations utilized if patients are not progressing through therapy or if have reached a plateau and abilities as well as restrictions need to be assessed Job site evaluations appropriate if concerns re: ergonomics

52

E. Final Thoughts:

•

It is the

patient

, not the diagnostic test, that is treated

•

80 %

of patients will recover from acute low back pain within 3 days to 3 weeks,

with or without treatment

, with up to

90 %

resolved in 6-12 weeks

53