LOWBACKPAIN

Pamela Rockwell, DOClinical Assistant ProfessorDepartment of Family MedicineUniversity of Michigan

INTRODUCTION

The Goal of this lecture is to address the assessment and management of acute low back pain and review the “red flags” one must identify in determining which patients may have a serious underlying condition.

INTRODUCTION

• It will also include the use of imaging modalities: when are they necessary and which ones to use?

• The information presented here is partly derived from the Acute Low Back Pain guideline developed at the University of Michigan Medical Center.

Some facts• Low back problems are the second most common

symptomatic reason expressed by patients for office visits to primary care physicians.

• Back problems are the most common cause of disability for persons under the age of 45.

• Among working-age people surveyed, 50% admit to back symptoms each year.

DEFINITION OF ACUTE LOW BACK PAIN (LBP)

• Acute LBP is defined as activity intolerance due to back-related symptoms less than 3 months duration.

• Back symptoms include pain in the back between the ribcage and the gluteal folds as well as back-related leg pain (sciatica) with or without concomitant truncal back pain.

KEY POINTS• Up to 90% of patients with acute LBP recover within 1

month.• The majority of acute LBP problems resolve within 4-6

weeks and can be managed by a primary care physician.• Only about 15% of patients can be given a definitive

diagnosis. The majority have nonspecific back symptoms.• 80% of the population will experience at least one episode

of disabling low back pain during their lifetime.

KEY POINTS

• Approximately 40% of persons initially seek help from a primary care physician, 40% from a chiropractor, and 20% from a sub-specialist.

KEY POINTS

• First contact physicians should identify serious or complicated causes of acute low back and refer as appropriate.

• Referral to a spine surgeon should occur for serious conditions such as cauda equina, spinal Infection, or fracture, or symptoms of nerve root compromise and neurogenic claudication severe enough to warrant surgical intervention.

Interesting Fact

• Patients who undergo surgery for disc problems have better outcomes at 3 months than those who elect conservative therapy with medical management (physical therapy and medication).

• However, outcomes at 1 year are the same as with medical management.

ASSESSMENT: TAKING THE HISTORY

As with evaluating most other patient complaints, obtaining a thorough history is very important in evaluating your patients with low back pain. Potential Serious Underlying Conditions which one must screen for: fracture, tumor, infection, and cauda equina syndrome.

THE HISTORY

• One must ask for the location of symptoms: which part of the back or leg is involved.

• The duration of symptoms and mechanism or onset of symptoms – insidious or with specific trauma is important to ask.

• The character or description of the pain: mechanical, radicular, claudicant, non-specific, etc. should be elicited.

THE HISTORY

Relieving or exacerbating factors ought to be discovered. These can give clues to the origin of the pain. For example, the motion of forward flexion relieving the pain may indicate spinal stenosis as etiology of the pain, whereas coughing, sneezing, or Valsaalva maneuvers eliciting the pain may indicate a herniated disc as the problem.

THE HISTORY

• Is there numbness, weakness, bowel or bladder symptoms?

• Are there constitutional symptoms such as fever or unexplained weight loss?

Neurologic history is important:

THE HISTORY

• Has there been previous spinal surgery or treatments?

• Are there temporal factors: no relief with bed rest or worse at night may raise the flag for cancer whereas morning stiffness points towards ankylosing spondylitis.

THE HISTORY

• History of cancer, IV drug abuse, signs or symptoms of infection such as a UTI, skin infection, etc?

• Any medications such as corticosteroids which may make the patient immunocompromised?

RED FLAGS

Suggesting possible Neoplasm or Infection:

• Age over 50 or under 20

• History of cancer

• Unexplained weight loss

RED FLAGS

Suggesting possible Neoplasm or Infection:

• Risk factors for spinal infection: recent bacterial infection like a UTI, hx of IV drug abuse, immunosuppression from steroids, transplant, or HIV.

• Pain that worsens when supine: severe nighttime pain.

RED FLAGS

Suggesting possible compression fracture:

• Minor trauma.

• Strenuous lifting, especially in the older or osteoporotic patient.

• Corticosteroid use.

RED FLAGS

Suggesting possible cauda equina syndrome:

• Saddle anesthesia (numbness on the area of the body that would touch a saddle if riding a horse).

• Recent onset of bladder dysfunction such as urinary retention, increased frequency, or overflow incontinence.

RED FLAGS

Suggesting possible cauda equina syndrome:

• Severe or progressive neurology deficit in the lower extremity such as “foot drop” or weakening of the lower extremity muscles

• Unexpected laxity of the anal sphincter, perianal/perineal sensory loss

PHYSICAL EXAM (PE)

• This should take no more than 5 minutes.

• The patient needs to be in a gown, or in shorts or underwear to properly observe the back.

PHYSICAL EXAM (PE)

• The exam is generally done in three parts: with the patient standing, seated, and lying down if possible, permitting the patient’s mobility and ability to assume these positions.

• The exam should start with observation of the patient’s gait and general appearance and this may be documented in the record.

PE: STANDING

Look for scoliosis, kyphosis, flattening of the lumbar curve or exaggeration of lumbar lordosis.

From Human Anatomy , Martini & Timmons

PE: STANDING

Palpate the spinous processes for tenderness (this may also be performed with the patient seated). If present, this is suggestive of, but not specific for spinal fracture or infection.

PE: STANDING

Palpate the paravertebral muscles for spasm, hardening, trigger points. This may help to identify root levels of dysfunction.

PE: STANDING

Check for mobility by having the patient bend at the waist with their knees straight.

PE: STANDINGHave the patient extend and flex their back, side bend, and rotate as you assess their range of motion.

RANGE OF MOTION ASSESSMENT

• One example of how this may help diagnosis: increased discomfort with hyperextension is noted with facet joint involvement and spinal stenosis, relieved with forward flexion.

• Another example: with disc disease, lateral flexion is often preserved, whereas forward flexion is not.

PE: STANDING

Test some nerve root innervation; 10 toe raises or toe walking will test plantar flexion and calf muscles innervated by S1.

PE: STANDING

Heel walking or heel raises test ankle and toe dorsiflexor muscle strength innervated by L5 and some L4 nerve roots.

PE: STANDING

Single squat and rise tests the quadriceps, mostly innervated by L4 nerve root.

PE: SEATED

The Straight Leg Raise implies significant nerve root irritation when positive.

PE: SEATED

Simply straighten out one leg in extension with the patient seated and if the patient complains of pain or leans back to reduce tension of the nerve, this is considered a positive test.

PE: SEATED

• Thorough evaluation of muscle strength testing should be done.

• Have the patient raise each thigh off the table against your resistance.

PE: SEATED -MUSCLE STRENGTH

Have the patient extend as well as flex the lower legs against resistance.

Document gross muscle testing.

PE: SEATED-NERVE ROOT TESTING

• Patellar reflex tests mostly L4.

• Hamstring reflex tests pure L5.

PE: SEATED-NERVE ROOT TESTING

Achilles reflex tests mostly S1, Babinski or plantar reflex helps to differential a spinal cord lesion – upward toe suggests a lesion above L1.

PE: SEATED-NERVE ROOT TESTING

Dorsiflexion of the foot tests L5 and some L4.

PE: SEATED-NERVE ROOT TESTING

Knee extensor strength tests L2-L4.

PE: SEATED-NERVE ROOT TESTING

Skin testing for sensation to rule out numbness and parasthesias should be performed.

PE: LYING SUPINE

Make sure to evaluate the Hip, especially in the young and the old: flex, internally rotate the hip as you put it through its range of motion.

PE: LYING SUPINE

The Straight Leg Raise (SLR) test should be done supine as well as seated: normally, patients can have their straight leg passively raised, flexing at the hip to 70 degrees without pain.

From Clinical Diagnosis, R. Judge etal

PE: LYING SUPINE

Pain below the knee at less than 70 degrees aggravated by dorsiflexion of the ankle and relieved by plantar flexion of the ankle or external limb rotation is most suggestive of tension on the L5 or S1 nerve root related to disc herniation.

PE: LYING SUPINE

• Crossover Pain occurs with raising the leg in a SLR on the non-painful side of the back, causing pain on the opposite side.

• This is a stronger indication of nerve root compression than pain elicited from raising the affected side.

DIFFERENTIAL DIAGNOSIS

• Once the History is obtained and the Physical Exam is performed, you should think about your Differential.

• There are SPINAL causes of LBP, METABOLIC causes, and NEOPLASTIC causes.

SPINAL CAUSES

• Mechanical: Musculoligamentous strain, degenerative joint/disc disease, herniated lumbar disc, spondylolitheses, spinal stenosis.

• Inflammatory: ankylosing spondylitis, inflammatory bowel disease, psoratic arthritis, Reiter’s

• Infectious: pyogenic or tuberculoys osteomyelitis, epidural abscess.

Spinal causes of LBP can be broken down into three categories:

METABOLIC CAUSES

Metabolic causes of LBP:

• osteoporosis

• Paget’s disease

• Osteitis fibrossa – hyperparathyroidism

• Osteomalacia and renal osteodystrophy

NEOPLASTIC CAUSES

Neoplastic causes of LBP:

• cauda equina syndrome, cord and canal tumors.

• multiple myeloma.

• metastatic malignancy: lymphoma and leukemia.

NON-SPINAL CAUSES

Non-spinal causes of LBP:

• Visceral

• GU/GI: pyelonephritis, nephrolithiasis, pancreatitis, endometriosis

• Abdominal aortic aneurysm

LABORATORY AND RADIOGRAPHIC TESTING -WHEN TO ORDER?

• Symptoms less than 1 month duration generally do not warrant any testing.

LABORATORY AND RADIOGRAPHIC TESTING -RED FLAGS PRESENT

• Plain films, CT. CT-myelography, MRI may be warranted for persistent (>1 month) sciatica, worsening of symptoms despite proper treatment.

• Testing is warranted if any “red flags” are present. Obtain a CBC, ESR, UA, plain x-ray films if considering cancer or spinal infection.

MEDICAL MANAGMENT

• Pharmacotherapy

• Manual medicine / physical therapy

• Modalities: ice, heat, electrical stimulation, untrasound.

• Orthotics

• Short course of bed rest not often prescribed. If so, then only for a few days when symptoms are severe.

PHARMACOTHERAPY: ANALGESICS

• Acetaminophen is the safest, without the risk of GI side effects.

• NSAIDS – may give up to 30% risk of GI side effects. Ibuprofen usually used.

• Narcotics not often given.

PHARMACOTHERAPY: MUSCLE RELAXANTS

• Sometimes helpful when spasm is present.

• Valium also used as a muscle relaxant.

MODALITIES

• Ice: for 20 minutes at a time over the painful area..

• Stretching: gradual gentle stretching is helpful.

• Physical Therapy with manual (manipulation) therapy, McKenzie exercises, reconditioning, mobilization, to list some of the modalities available.

ORTHOTICS

• Shoe insoles or heel lift if short leg is part of the condition.

Acute Low Back Pain Summary

• 90% of patients with acute LBP recover within a month.

• First contact physicians should identify serious or complicated causes of acute LBP and refer as appropriate.

• Outcomes for patients 1 year after back surgery are the same as those patients after one year of conservative treatment.