Diagnosing Low Back Pain in the Elderly

G. Barry Robbins D.O., FACN

Associate Professor of Neurobehavioral Sciences

KCOM A College of ATSU

Risk Factors of LBP

• Repetitive lifting• Vibration• Smoking and Alcohol abuse• Multiple pregnancies• Inactivity• Osteoporosis• Familial Trend• Anxiety associated with depression

Prevalence of LBP

• Increases with age• Reaches 50% in persons > 60 yrs.• 5% of population yearly (900,000 people)• 80% of population in lifetime• 10% LBP lasts > 6 weeks• Chronic LBP

– occurs in only 5%

– Incurs 87% of cost

Age Issues in Back Pain

• Osteoid osteoma in teenager• Inflammatory bowel in 20 year old• Multiple Myeloma in 70 to 80 year old• Abdominal Aneurysm in 70 to 80 year

old• Sex Ratios in Low back Pain

– Osteoporotic fractures > in women– Fibromyalgia > in women

Low Back Pain in the Elderly

• Due to a wide range of potential causes of low back pain in the elderly makes its diagnosis and management more challenging than in younger patients.

4 Important Areas to Assess in the Elderly

• Characteristics of the pain

• Presence of malignancy

• History of non-spinal medical problems

• Psychosocial status

Causes of lower Back Pain in Older patients

• Acute LBP– Lumbar strain or sprain– Vertebral compression fracture due to

osteoporosis– Abdominal aortic aneurysm– Polymyalgia rheumatica

LBP (cont’)

• Chronic LBP– Aging-related degenerative disk and joint

disease– Malignancy– Paget disease– Fibromyalgia– Diffuse idiopathic skeletal hyperostosis

LBP (cont’)

• Predominant leg pain associated with LBP– Trochanteric bursitis– Osteoarthritis of the hip– Lumbar canal stenosis– Intervertebral disk herniation

Key Points of the Medical History

• Careful evaluation is crucial due to the broader differential diagnosis in the elderly

• Four important areas:– Characteristics of the pain

– “Red flags” for cancer

– Non-spinal medical problems

– Psychosocial factors

1. Characteristics of the Pain• Location

– leg pain > back pain• Suggests lumbar radiculopathy

• Sensitivity 95% and specificity of 85%

– Leg pain aggravated by walking and standing but relieved by sitting suggests spinal stenosis

– Anterior thigh pain suggests upper lumbar radiculopathy or hip disease

• Onset– Gradual, slow – degenerative mechanical pain

– Sudden and severe – osteoporotic compression fracture.

• Effect of positional change– Constant unrelieved with position change – cancer

– Mechanical – relieved when supine, increased when position is changed

2. Red Flags for Cancer• Cancer

– 0.5% of all LBP– 7% of LBP over 50 years of age– 80% of all LBP patients assoc/w cancer are over 50

years of age

• Red Flags– Prior history of cancer (33.3%)– Pain that is usually constant– Pain at night that disturbs sleep (90%)– Unexplained weight loss > 10# in 3 months (15%)– Back pain that progresses despite appropriate

treatment

Cancer (Deyo 1988)

Sensitivity Specificity

Age > 50 0.77 0.71

Unexplained weight loss (>5kg in 6/12)

0.15 0.94

Previous history of cancer

0.31 0.98

Not improving with medical care (1/12)

0.31 0.90

Cancer (cont’)

Sensitivity Specificity

No relief with bed rest

1.00 0.46

Insidious onset 0.61 0.42

Duration > 1/12 0.50 0.81

Recent back injury 0.00 0.82

Thoracic pain 0.17 0.84

Cancer

• 2/3 of cancer cases presents as back pain• Most common: Breast, lung, kidney or prostate• Multiple myeloma is most common• Non spinal malignant diseases presenting with

LBP– Pancreatic carcinoma– Renal cell cancer– Intrapelvic tumors– Lymphoma with retroperitoneal lymphadeopathy

Cancer (cont’)

• 78 – 94% LBP due to cancer have Sed Rates >20 mm/hr

• Plain lumbar radiography is 65% sensitive• MRI and CT are 95% sensitive in detecting

cancer ( MRI is preferred)• Bone scan is 95% sensitive but may be normal

in multiple myeloma

Nuclear Medicine

Metastatic Bone Disease

3. Non Spinal Medical Conditions

• Diabetes affects 15% of adults > 45 y– Peripheral vascular disease

– Risk of renal toxicity from NSAIDs

• Ischemic heart disease and CHF– At risk for renal toxicity from NSAIDs

– Unable to comply with physical therapy program

• Severe comorbidity causing surgical risk

4. Psychosocial Conditions• Job dissatisfaction• Pre-existing psychiatric disorders

– Depression– Anxiety– Substance abuse

• Secondary financial gain– Personal injury litigation– Workers compensation

• Activities of independent living or caring for spouse

• Transportation issues

Clues to Psychological Component in LBP

• Pain is unrelenting• Pain and numbness involves entire leg gives

way• If pain level exceeds physical findings• Nothing helps• Everything makes the pain worse

Symptom Magnification Examination

• Waddel’s 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

The Physical Examination

• Routine with special observation of– Spinal posture (kyphosis) due to vertebral

compression– Increased muscle tone and stiffness

(unrecognized Parkinson’s disease presenting as bone pain

– Leg pain always check distal pulses (to distinguish vascular from neurogenic claudication)

Causes of Acute LBP in the Elderly

• Lumbar strain or sprain – Frequent– Due to age related changes and deconditioning

– At greater risk for stretch injury

– Pain increased with compression fractures and kyphosis

– Pain of a strain is usually acute but if due to kyphosis is usually gradual with prolonged standing, relieved in supine position

Vertebral Compression Fracture

• Most commonly due to osteoporosis especially in women

• Occur spontaneously or with minimal trauma• Pain is acute and aggravated by movement,

most comfortable when motionless• Plain lateral films, Bone scan, or MRI usually

distinguishes acute from older Fx’s

Compression fracture

Sensitivity Specificity

Age > 50 years 0.84 0.61

Age > 70 years 0.22 0.96

Trauma 0.30 0.85

Corticosteroid use 0.06 0.995

Radiograph (left) Vertebral compression fracture (arrow) in an elderly patient. Bone scan (right shows increased

uptake in the acutely compressed vertebra.

Abdominal Aortic Aneurysm

• Occur in 4% of persons > 50 yr.s• Men>Women• More common in persons with Peripheral Vascular

Disease• Most are asymptomatic• 10 – 15% present with: Back pain

– Often associated with abdominal pain– Radiating to the hips and thighs– Aneurysm rupture assoc/w a sudden dramatic increase in pain

• Pulsatile abdominal mass in 50%• AP and lateral lumbar spine films – 70% curvilinear

aortic calcifications• Abdominal ultrasound or CT – 100% sensitive

Polymyalgia Rheumatica

• Sudden (often overnight) onset of pain and stiffness in the neck, upper back, shoulders, lower back, buttocks and hips

• Usually in persons > 50 yr.s (prevalence increases with age)

• Giant cell arteritis found in 40%• Sed rate > 40mm/hr.• Dramatic response to trial of low dose

prednisone confirms the diagnosis

Causes of Chronic LBP in the Elderly

• Degenerative disk and joint disease– Common– MRI or CT demonstrate disk bulging or

protrusion and spinal stenosis in persons with no symptoms

– Careful not to attribute LBP symptoms to these frequently asymptomatic and near universal degenerative changes

Degenerative Disk and Joint Dx

• Degenerative changes occur in the spinal segment (3 components)– Intervertebral disk - water content and thins

– Paired facet joints - stress and shear

– Vertebral body - anterior (osteoporotic) collapse

• Changes affect the neuro-foramina and ligaments (buckle)

• Symptoms are insidious and mechanical in character.

• Pain s with movement and prolonged activity and relieved by rest.

Diagnostic Imaging Studies

• More cautious interpreting in older patients due to false-positive findings increase with age.

• Medical and psychosocial comorbidity increases significantly with age.

George Washington Study - 1990

• 67 patients who never had Lower Back Pain or Sciatica– < 60 y o

• MRI + 20% Herniated Disc• MRI + 50% Bulging Disc

– > 60 y o• MRI + 30% Herniated Disc• MRI + 80% Bulging Disc• MRI + 20% Spinal Stenosis

Diagnosis Test Sensitivity Specificity

CT 0.90 0.70

MRI 0.90 0.70

Disc“Herniation”

CT Myelo 0.90 0.70

CT 0.90 0.80-0.95

MRI 0.90 0.75-0.95

SpinalStenosis

Myelogram 0.77 0.70

Sensitivity/Specificity

Paget Disease

• Common, found in:– 3% of adults > 40yr– 10% of adults > 80yr

• 40% have LBP (most are asymptomatic)• Pain may be:

– Bone pain (deep, aching, and constant)– Arthritic pain

• X-Ray = localized bone enlargement; vs sclerotic changes (prostate cancer)

Paget Disease

• Diagnosis– Bone scan more sensitive than X-Rays Serum alkaline phosphatase (osteoblastic) Urinary hydroxyproline (osteoclastic)– More specific indicator of bone reabsorption:

Urinary excretion of pyridinoline or deoxypyridinoline

Diffuse Idiopathic Skeletal Hyperostosis (DISH)

• Known as Forestier disease• Characterized by exuberant ossification of

spinal ligaments• Men > 50yr• Seen radiographically in 10% of persons > 65yr• Incidence in persons with diabetes• Stiffness in back is the primary symptom• Pain (thoracolumbar) in 50% of affected

persons

Diffuse Idiopathic Skeletal Hyperostosis (DISH)

• Diagnosis– X-Rays reveal flowing anterior calcification

along at least 4 contiguous vertebrae confirm the diagnosis

– Disk height is preserved– Sacroiliac joints are not involved– Test for acute-phase reactants are normal

DISH SYNDROME

DISH SYNDROME

Evaluating Non-Radicular, Non-Spinal Causes of Leg Pain in the Older Patient

• May produce “pseudo-sciatica”– Trochanteric Bursitis

• Lateral aspect of hip; 40% extends down lateral thigh

• Many unable to lie on affected side due to pain• Direct tenderness over and around the greater

trochanter.• Pain provoked by forced hip abduction• X-Rays occasionally reveal calcifications around

the trochanter

Non-Radicular, Non-Spinal Pain

• Osteoarthritis of the Hip– Pain is felt in the buttocks, groin, or anterior thigh,

at times radiating to the knee.

– Resembles L2 or L3 radicular pain

– Physical exam indicating hip disease – pain with internal and external rotation of the hip, often with a in joint mobility

– X-Ray = joint space narrowing and subchondral sclerosis with osteophyte formation

Lumbar Canal Stenosis

• Due to degenerative spinal changes including:– Facet joint hypertrophy

– Bulging or herniation of the intervertebral disk

– Thickening and buckling of the ligamentum flavum

• Most common reason for spinal surgery in persons > 65yr

CAT

Osteoarthritis of the Spine

Sclerotic and Hypertrophied

Facets

Lumbar Myelogram

Herniated Nucleus Pulposus with Central

Canal Stenosis

Lumbar Canal Stenosis

• Diagnosis primarily based on clinical history• Classic symptom is pseudoclaudication

– Pain, numbness, weakness, or heaviness in one or both legs provoked by walking or standing.

– Pain is relieved by sitting or forward flexion– The “Grocery Cart Syndrome”

• Physical exam is unimpressive – Provocative test is the development of posterior thigh

symptoms after 30 sec of lumbar extension– CT or MRI confirms the diagnosis (Critical to correlate

the findings due to MRI findings of spinal stenosis are seen in asymptomatic patients)

Red Flags of Spinal Stenosis Pseudo-claudication

• Vascular – true claudication when walking (Diminished pedal pulses, trophic changes of skin, etc)

• Neurogenic– More likely to occur simply with standing

– When walking, more likely to be flexed (e.g. pushing a shopping cart)

– Numbness and tingling are common

– Symptoms worsen with coughing or sneezing

– No pain when seated with the spine flexed

Cauda Equina Syndrome

• A Medical Emergency– Causes

• Fracture/Dislocation• Neoplasms• spinal stenosis• massive herniated disks

• RED FLAGS– Recent onset of urinary problems– Saddle Anesthesia– Severe or progressive neuro deficits in LEs– Unexpected laxity of anal sphincter– Major motor weakness in quadriceps and foot

drop (Multiple nerve roots)

Examination

• Pain radiating to lower leg

• Presence of Neurological deficits (M,S, DTRs)

• Progressive neurological deficits

• Pain may stay same but neurological status may change ---Recheck in 3 - 7 days if:– severe pain– progressive symptoms by history– mild neurological deficits on initial exam– Inconsistent finding due to guarding or pain on

motion

Assessing Functional Capacity in the Older Patient

• LBP may compromise already marginal functional status

• May require expanded social service intervention

• Compliance of a therapeutic exercise program may not be possible

• Mild cognitive impairments significantly limits therapeutic choices