Only 10 to 20% of patients have a specific anatomic etiology that can be clearly and objectively identified. Non-mechanical "serious" causes of low back pain requiring urgent recognition are rare, representing less than 1% of unselected patients with LBP.
Radiographic "abnormalities" identified on plain X-rays, computerized tomography (CT) scan or magnetic resonance imaging (MRI) are frequently clinically irrelevant. Indeed, we know little of what causes spinal pain, and correction of even obvious structural abnormalities often fail to relieve pain.
True sciatica, defined as radicular symptoms related to appreciable nerve root compression, occur in only 5% of patients presenting with low back pain.
Diagnosis
Up to 85% of patients with back and neck pain cannot and perhaps should not be given a definitive diagnosis. As noted earlier, there is a often a poor association between symptoms, pathologic findings and imaging results. The purpose of the initial evaluation is to identify:
- Serious underlying systemic disease manifesting as back pain
- Neurologic deficit which may require surgical evaluation
- Significant social or psychological distress that may prolong pain and classify back pain symptoms into certain categories:
A. Potentially serious spinal conditions
B. Radicular back pain
C. Non-specific back pain
A focused history and physical examination can identify pertinent historical red flags, significant neurological deficits and nonorganic physical findings; this can be used to classify back and neck pain symptoms.
Relevant historical information includes the onset, duration, location and severity of pain. Alleviating and aggravating factors such as sitting, standing, walking, bending, lifting, coughing and sneezing should be noted. The impact of symptoms on activity and response to previous therapy are important in the care of back and neck pain problems. Use of instruments, such as a pain drawing or visual analogue scale is often valuable to augment the history.
A focused physical examination is recommended and should include assessment of upper and lower extremity sensation, strength including proximal and distal manual muscle testing and reflexes (biceps, triceps, brachioradialis, patella, Achilles).
Additional tests such as a straight leg raise, spinal range of motion, and palpation are recommended in the assessment of neck/back pain patients.
In addition assessment of gait, peripheral pulses, abdominal, vaginal and rectal examination, breast examination, assessment of hamstring and triceps surae flexibility and Babinski add to the thoroughness of a focused examination and may rule out visceral diseases unrelated to the spine including diseases of the pelvic organs, kidneys, gastrointestinal tract and aorta. Cerebral disorders can mimic spinal problems by causing arm or leg weakness or numbness; helpful distinguishing symptoms and signs include the presence/absence of neck pain/headache, and cranial nerve abnormalities, especially of the facial nerve.
Clinical Evaluation to Rule Out Systemic Disease
Clinical evaluation to rule out systemic disease Malignancy is the most worrisome underlying systemic cause of back and neck pain. Even so, cancer accounts for less than 1% of episodes of spinal pain. Metastatic cancer and primary tumors such as multiple myeloma are more common than spinal infections (osteomyelitis, epidural abscess, etc.) or inflammatory conditions such as ankylosing spondylitis. Most spinal infections are blood borne from other sites, such as indwelling urinary catheters, skin infections or injections of "street drugs." About 80% of patients with an underlying malignancy are over age 50.
Red Flags
|
History
|
Physical Findings |
| Fever |
Spine Tenderness to Percussion |
| Chills |
Lymphadenopathy |
| IV Drug Abuse |
Cachexia |
| Recent Urinary Tract Infection |
Skin Erythema |
| HIV/AIDS |
Neurologic Deficit |
| Corticosteroid use, Diabetes |
|
| History of Cancer |
|
| Unexplained Weight Loss |
|
| Increasing Pain |
|
| Nocturnal Pain |
|
| Pain unrelieved by bed rest |
|
| Metabolic Bone Disease |
|
| Vascular Deficit |
|
| Progressive Neurologic Deficit |
|
Clinical Evaluation for Neurologic Compromise
Over 90% of disc herniations in the low back occur at either L4-5 or L5-S1 intervertebral levels. In older individuals, herniations at L3-4 are quite common. Neurologic exam should address ankle dorsiflexion strength, great toe dorsiflexion strength, knee flexor and hip extensor strength, medial hamstring and ankle reflexes, and sensory examination as these are the most likely deficits seen in patients with L5 or S1 nerve root impairments.
Ipsilateral straight leg raising is a moderately sensitive test for nerve root irritation. Crossed straight leg raising sign is a highly specific sign for nerve root irritation.
Cauda equina syndrome is an indication for emergent surgical referral. Urinary retention, saddle anesthesia, lower extremity weakness, decreased anal sphincter tone may be seen in this syndrome. This, and other surgical indications, are discussed later.
C5-6 is the most common level of disc herniation in the cervical spine. Complaints of scapular pain or anterior chest wall pain may be associated with radicular pain/paresthesias and arm weakness. Evidence of motor loss and gait abnormalities in radiculopathy may indicate spinal cord compression and may be a malignant finding.
Thoracic spine abnormalities (tumor, discs) are rare. Thoracic spinal tenderness, intercostal pain, and myelopathy are often seen.
| Disc |
Root |
Reflex |
Muscles |
Sensation |
| L3-L4 |
L4 |
Patellar reflex |
Anterior tibialis |
Medial leg and medial foot |
| L4-L5 |
L5 |
None |
Extensor hallucis longus |
Lateral leg & dorsum of foot |
| L5-S1 |
S1 |
Achilles reflex |
Peroneus longus & brevis |
Lateral foot |
Red Flags
| History |
Physical Findings |
| Pain increased with cough |
Positive straight leg raise |
| Sneeze, Valsalva |
Crossed straight leg sign |
| Leg pain> back pain |
Reflex asymmentry |
| Numbness, tingling in dermatomal pattern |
Sensory deficits in dermatomal pattern |
| Increased pain with sitting, bending, lifting |
Weakness in myotomal pattern |
| Severe motor loss, i.e. foot drop |
Pathological reflexes |
| Arm pain> neck pain |
Loss of position sense (long tract signs) |
Evaluation of Psychosocial Factors Affecting Back Pain
Attention to psychological and social economic problems in the individual's life is recommended. Such non-physical factors can complicate both the assessment and treatment of back pain. Psychosocial stressors including perceived high levels of stress, family or job disharmonies, previous treatment failures, substance abuse and job dissatisfaction can compromise outcome.
Evidence of psychological distress should be sought during the examination. A number of features of the history and physical exam which may be markers of psychological distress are noted below:
Red Flags
| History |
Physical Findings |
| Non-anatomical pain complaint |
Superficial tenderness |
| Non-dermatomal numbness |
Non-dermatomal sensory loss |
| Intolerance of treatments |
Increased pain with axial loading |
| Constant pain |
Increased pain with rotation distraction |
| Emotional |
Overt pain behaviors |
| |
SLR improves with distraction |
Criteria for Radiographic Studies
In the past, plain x-rays were routinely ordered for patients with back or neck pain. However, routine plain x-rays are unnecessary in the majority of patients presenting with initial onset of pain. Many radiographic anomalies are equally common in symptomatic and asymptomatic persons (single disc space narrowing, facet joint abnormalities, spondylosis, spina bifida occulta).
In the absence of neurologic deficits, plain radiography is inappropriate for patients with less than 1 week of pain, and of uncertain value for patients with 1 to 7 weeks of pain.
The lumbar obliques are probably unnecessary for the majority of patients needing imaging studies. The AP and lateral views alone provide substantial information and eliminate two-thirds of the radiation exposure and costs.
Widespread use of CT and MRI has occurred due to the noninvasive properties of these tests, superior resolution compared to myelography and customer demand. Unfortunately, due to the high sensitivity and low specificity of these diagnostic studies, clinical difficulties frequently arise. Many "normal" individuals frequently have abnormal imaging studies. Abnormal MRI findings may lead to unnecessary treatment with disappointing results.
Clinical indicators for radiography
- Significant trauma; evaluate possible fracture
- Neuromotor deficits; identify underlying spondylolisthesis or malignancy
- Unexplained weight loss (> 10 pounds in 6 months) or lymphadenopathy
- Drug or alcohol abuse; increased risk of trauma and osteoporosis
- History of cancer
- Fever (temperature greater than 100 degrees Fahrenheit)
- Long term use of corticosteroids
- Suspicion of ankylosing spondylitis
- Failure to improve after 4 to 6 weeks of non-operative therapy
Back and/or neck pain and age greater than 50 years old alone is not an absolute indication for x-rays. However, 80% of patients with cancer are over age 50.
Clinical indicators for advanced diagnostic studies
- Objective neurologic deficits
- Potential surgical treatment
- Signs of spinal stenosis
- Pathological reflexes
- Cervical spondylolytic myelopathy
Criteria for Laboratory Tests
The only value of laboratory tests is to help rule out underlying systemic disease. Since systemic illness is a rare cause of back pain, most positive laboratory tests are likely to be false positives. The ESR may be a useful screening test for patients with possible infection or cancer. Rarely, a CBC, U/A, SPEP, C-reactive protein, thyroid function test, alkaline phosphatase, or uric acid may be indicated. More rarely, consideration for inflammatory arthropathies may be entertained, including antinuclear antibodies and serum antigens including HLA.B27. These should almost never be done initially.
Criteria for Electrodiagnostic Studies
EMG/nerve conduction studies may be appropriate in the evaluation of low back and radicular pain at least 6 weeks after the development of symptoms. Electrodiagnostic studies are complementary to the history, physical examination and radiographic imaging studies. No physiologic testing is necessary if the diagnosis is obvious on clinical examination and correlates with other nerve radiographic studies. However, it may be helpful to evaluate vague pain and sensory symptoms, rule out an underlying or superimposed peripheral neuropathy and assist in establishing the level of radicular involvement.
Initial Evaluation Recommendations
In the absence of "red flags," no diagnostic studies are indicated in the first 4 to 6 weeks after onset of pain. At that time, if no improvement is noted, diagnostic studies may be considered.
Treatments
The prognosis for patients with acute back and neck pain is quite favorable. Recurrences are common but frequently resolve rather rapidly. Initial treatment may include reassurance, patient education, and activity modification. Manual therapy and physical therapy often are recommended.
Brief Bed Rest
Even though bed rest in the historical mainstay of therapy for acute low back pain, it is probably of no value. Brief (1 to 2 days) if any bed rest is sufficient. Multiple studies have demonstrated no differences between speed of pain resolution, functional recovery, or satisfaction with care with 2 days of bed rest versus 7 days of bed rest. In addition, patients with no or limited bed rest return to their normal activities much sooner. Lengthy bed rest contributes to deconditioning, with loss of cardiopulmonary and muscle fitness, and may contribute to anxiety, depression, and decreased motivation.
Bracing
Neck or back bracing may be occasionally of value for a few days after trauma. Other than for fracture, there are no indications for longer-term immobilization. Indeed, this contributes to loss of muscle conditioning and may be harmful over the long term.
Reassurance
Back pain is an extremely common condition and has a very favorable prognosis. The natural history is one of rapid recovery and return to activity. Reassurance and education regarding the natural history of back pain should occur during the initial evaluation. "Fear of pain ... may be more disabling than pain itself."
Medications
The goal of medication is to relieve symptoms, allowing for quick return to functional daily activities. When choosing a medication, contraindications, efficacy, complications/risks, cost, and patient compliance should be assessed.
Non-steroidal anti-inflammatory drugs (NSAIDS) have anti-inflammatory, analgesic and antipyretic properties. Their use in acute musculoskeletal injuries is well established. Several NSAIDS have been shown to be effective in randomized clinical trials (Naprosyn, Diflunisal, and Piroxicam). Most NSAIDS are probably beneficial but the cost, side-effect profile (especially GI distress) and length of treatment need to be considered. The differences between agents are in duration of action, degree of side effects, and individual patient tolerance rather than effectiveness.
Acetaminophen has been shown to relieve pain in osteoarthritis and plays a strong role in the treatment of back pain. This medication should be a first line drug.
Use of Ibuprofen plus Acetaminophen is recommended initially for pain relief. Use of more than one NSAID simultaneously should be avoided. Allow up to 2 weeks for maximal anti-inflammatory effect.
Muscle relaxants including Cyclobenzaprine are often prescribed in the acute phase of pain. Their efficacy over placebos is uncertain; some studies have demonstrated a very slight improvement in ADL function when Cyclobenzaprine and Diflunisal were given together in the acute phase. Opioids are rarely indicated for treatment of acute neck/back pain. In acute disc herniations, narcotic pain medication may be necessary but should be limited to up to 3 to 5 days.
Corticosteroids have powerful anti-inflammatory effects. Side-effects may include hyperglycemia, hypertension, transient adrenal suppression and increase risk of avascular necrosis and infection. No studies have demonstrated effectiveness of oral steroids alone in the treatment of back pain, and they should rarely be used initially.
Chiropractic Treatment
Utilization studies have shown chiropractic management in up to 40% of occupational back claims. Early experiences suggest that integration of chiropractic treatment (SMT) into multimodal management improves outcome.
Indications for chiropractic treatment
Spinal manual therapy (SMT) is often indicated in mechanical back or neck syndromes, particularly in the absence of radicular symptoms. It is critical that the referring physician remain informed regarding the patient's response to chiropractic management as well as the frequency and duration of treatment. Referral for chiropractic treatment (SMT) may be considered when:
? Mechanical neck and/or back pain symptoms predominate.
? SMT is integrated into a back stabilization program emphasizing improved strength, flexibility, and cardiovascular fitness.
Contraindications for chiropractic treatment
Certain contraindications to chiropractic treatment have been established.
A partial list of significant contraindicators includes:
- Acute lumbar disc herniation with defined, progressive neurologic deficit, particularly motor weakness
- Cauda equina syndrome
- Advanced osteopenia, idiopathic osteoporosis, long term
steroid therapy, etc.
- Vertebral basilar insufficiency
- Metastatic disease
- Infection
- Advanced degenerative joint disease involving segmental instability