Basics
Description
- Low back pain (LBP):
- Refers to pain in the area between the lower rib cage and the gluteal folds, often with radiation into the thighs
- Sciatica:
- Pain in the distribution of the lower lumbar spinal roots
- May be accompanied by neurosensory and motor deficits
- Pain classification:
- Acute: <6 wk
- Subacute: 6-12 wk
- Chronic: >12 wk
Etiology
- Nonspecific musculoligamentous source (great majority) (e.g., muscle, ligament, fascia)
- Herniation of the nucleus pulposus
- Degenerative joints or discs
- Spinal stenosis
- Anatomic abnormalities-especially spondylolisthesis
- Fractures from trauma and osteoporosis
- Underlying systemic diseases (minority):
- Neoplasm
- Infections
- Vascular (dissection, aneurysm, and thrombosis)
- Renal
- GI
- Pelvic organ pathology
Diagnosis
Signs and Symptoms
- Musculoligamentous:
- Poorly localized and dull back/gluteal pain without radiation past the knee.
- Usually no objective neurologic signs.
- Back spasm is a variable and poorly reproducible finding.
- Sciatica:
- Sharp, shooting, well-localized pain
- Leg complaints often greater than back
- May present with
- asymmetric deep tendon reflexes
- decreased sensation in a dermatomal distribution
- objective weakness
- Massive central disc herniation (cauda equina):
- Decreased perineal sensation
- Urinary retention with overflow incontinence
- Fecal incontinence
- Infectious processes:
- Fever
- Localized percussion tenderness of the vertebral bodies
- Bony lesion:
- Continuous pain that does not change with rest
- Constitutional symptoms
- Vascular etiology:
- Severe, often "ripping or tearing"Ł pain
- May be associated with cold or insensate extremities
History
- Can assist with focusing and narrowing differential diagnosis. Helps rule out concerning pathology for pain:
- Intensity
- Quality
- Location and radiation
- Onset
- Exacerbating or remitting factors
- Social or psychological factors
- Response to previous therapy
- Risk factors for serious disease:
- Fever
- Constitutional symptoms
- Trauma
- Age >60 yr
- History of cancer:
- Especially those that metastasize to bone
- Chronic steroid use
- IV drug use
- Recent instrumentation or bacteremia
- Night pain
Physical Exam
- Fever
- Spasm or soft tissue tenderness is a poorly reproducible finding:
- Vertebral tenderness sensitive but nonspecific for infection
- Straight leg raise-elevating the leg while supine reproduces sciatic symptoms:
- Ipsilateral raise highly sensitive but not specific
- Crossed leg raise highly nonspecific but insensitive
- Ankle and great toe dorsiflexion and ankle plantar flexion (L5, S1 nerve roots)
- Ankle deep tendon reflexes (S1)
- Dermatomal sensory exam:
- Assess for saddle anesthesia
- Rectal sphincter tone
Essential Workup
- Thorough history and physical exam, including detailed neurologic and vascular exam
- No specific tests are needed for uncomplicated musculoligamentous or sciatic pain
- Rapid diagnostic testing and vascular consultation concerning aortic etiology
Diagnosis Tests & Interpretation
Lab
- Urinalysis for suspected:
- UTI/pyelonephritis
- Prostatitis
- ESR:
- Highly sensitive, though nonspecific for infectious or inflammatory etiologies
- Used for screening to help rule out disease
Imaging
- Lumbosacral radiograph:
- Significant trauma
- Age >50-60 yr
- History or signs/symptoms of cancer
- Fever
- IV drug user
- Pain at rest
- Suspicion of inflammatory etiology
- Pain that does not improve after 4 wk
- Bedside US:
- Full bladder suggests urinary retention
- Abdominal aortic aneurysm (AAA)
- Abdominal CT if patient stable
- MRI:
- Suspicion of abscess:
- Fever, immunocompromised, IVDA, history of bacteremia
- Suspicion of metastatic tumor:
- Systemic cancer, weight loss
- Suspicion of hematoma:
- Anticoagulation, recent spinal anesthesia
- Rapidly progressing neurologic symptoms
- Urinary retention or fecal incontinence associated with back pain
- CT:
- Secondary modality for diagnosis of abscess, cancer, or massive disc when MRI unavailable
- Test of choice in imaging potential unstable fractures
- Excellent sensitivity to evaluate vascular etiology in stable patient
Differential Diagnosis
- Spinal origins-in the majority of patients no precise anatomic site is discovered:
- Musculoligamentous (majority)
- Discogenic
- Fracture
- Spondylolisthesis
- Ankylosing spondylitis
- Osteomyelitis
- Epidural abscess/hematoma
- Neoplasm
- Nonspinal causes:
- AAA
- Prostatitis
- Upper UTI
- Abdominal neoplasm
- Renal colic
- Aortic dissection
Treatment
Pre-Hospital
- Immobilization is not generally recommended for nontraumatic pain.
- Rapid transport for vascular concerns
Ed Treatment/Procedures
- NSAIDs:
- Musculoligamentous pain
- Renal colic
- Similar benefits as APAP but less optimal side-effect profile
- APAP: Considered 1st-line therapy for mild-to-moderate pain
- Moderate but conflicting evidence for benefit of NSAID and acetaminophen combination over each individually in postoperative pain
- APAP and NSAIDs not effective for sciatica pain
- Muscle relaxants:
- Cyclobenzaprine, methocarbamol, carisoprodol, or tizanidine
- Benefits must be balanced by side effects, mostly sedation, dizziness, and dry mouth
- Benzodiazepines:
- No clear difference from skeletal muscle relaxants
- Likely higher risk profile for addiction
- Narcotics:
- A reasonable (3-5 days) course may be given for severe pain not relieved by anti-inflammatory or APAP. Effective for neuropathic pain
- Risk benefit profile should be considered and discussed with patient
- Corticosteroids:
- No benefit in radicular or nonradicular back pain
- Spinal manipulation:
- A short course (<2 wk) may be helpful in acute LBP without sciatica
- Physical therapy/exercise:
- No clear consensus for indications
- May be helpful in symptomatic relief, preventing further episodes and teaching patients
- Acupuncture:
- Controversial, probable benefit for chronic musculoskeletal pain
- No clear benefit over other modalities
- Trigger point therapy with minimal to no evidence of benefit for chronic LBP not studied for acute
- Massage:
- May be beneficial when combined with exercises and education
- Heat/cold therapy:
- Limited evidence to support that heat wrap therapy may help reduce pain and disability for patients with back pain <3 mo. Improved as adjunct to exercise.
- Bed rest:
- Unhelpful to speed recovery and may impede improvement. If patient requires bed rest acutely or is symptomatically improved, 1 or 2 days may be recommended.
- Back exercises:
- Unlikely to be useful in acute phase; may assist with prevention of future episodes
- Expected recovery to pain-free state:
- Conflicting data, mostly in non-ED setting
- ~33% within 1 wk
- ~90% within 6-8 wk
- Low SES, female sex, baseline disability and chronic LBP significant for worse functional outcome at 1 and 3 wk
- Newer ED data suggests functional limitation in 50% of patients with pain at 3 mo.
- Recurrence is common: ~40%
Medication
First Line
- Acetaminophen: 500 mg (peds: 10-15 mg/kg, do not exceed 5 doses/24h) PO q4-6h, do not exceed 4 g/24h
- Hydrocodone/acetaminophen: 5/500 mg PO q4-6h
- Ibuprofen: 600-800 mg PO q6-8h (peds: 10 mg/kg q6h)
- Naproxen: 250-500 mg PO q12h
- Oxycodone/acetaminophen: 5/500 mg PO q4-6h
Second Line
- Cyclobenzaprine: 5-10 mg PO TID. Caution patient regarding drowsiness.
- Methocarbamol: 500-1,500 PO q6h. Caution patient regarding drowsiness.
- Valium: 5-10 mg PO q8h
- You may combine 1st- and 2nd-line therapies but side-effect profile will increase
Follow-Up
Disposition
Admission Criteria
- Severe pain with inability to ambulate
- Pain unresponsive to ED management
- Progressive neurologic deficits
- Signs of cauda equina syndrome
- Infectious, vascular, or neoplastic etiologies
Discharge Criteria
Uncomplicated presentation with ability to control pain and ambulate á
- Maintain a high suspicion for serious disease including vascular etiology, neoplasm, or infection.
- Have a low threshold for imaging or diagnostic testing.
- Follow up patients on NSAIDS or opioids more carefully for complications or adverse events related to therapy.
- Back pain is unusual in the pediatric patient; a high suspicion for an infectious etiology must be maintained.
- For musculoligamentous pain, a single trial found that Ibuprofen provides good pain control with a low side-effect profile.
Limited evidence suggests that strengthening and pelvic tilt exercises combined with routine prenatal care may have benefit in treating back pain; unclear if they prevent pain á
Issues for Referral
Urgent neurosurgical or orthopedic consultation for definite diagnosis or high suspicion for abscess or lesion (disc, neoplasm, or other) with rapidly progressive objective neurologic findings á
Follow-Up Recommendations
- Uncomplicated back pain: PCP in 1-2 wk
- New sciatica without neurologic findings: PCP or specialist in 7-10 days
- Complicated with sensory findings only or minimal motor symptoms: 24-48 hr
- Marked or rapidly progressive motor symptoms, or bowel/bladder findings warrant specialist consultation in the ED or transfer if unavailable.
Pearls and Pitfalls
- Consider MRI for history of IVDA to rule out epidural abscess or if concerns of nonbony spinal metastases.
- Elderly with minimal trauma may sustain fractures.
- Consider vascular etiology in elderly patients with 1st-time presentation of back pain.
- Advise patients that this is often a prolonged course and they should not expect rapid resolution.
- Opioids should be limited to a short course from the ED.
Additional Reading
- Cantrill áSV, Brown áMD, Carlisle áRJ, et al. American College of Emergency Physicians Opioid Guideline Writing Panel. Clinical policy: Critical issues in the prescribing of opioids for adult patients in the emergency department. Ann Emerg Med. 2012;60(4):499-525.
- Davies áRA, Maher áCG, Hancock áMJ. A systematic review of paracetamol for non-specific low back pain. Eur Spine J. 2008;17:1423-1430.
- Friedman áBW, O'Mahony áS, Mulvey áL, et al. One-week and 3-month outcomes after an emergency department visit for undifferentiated musculoskeletal low back pain. Ann Emerg Med. 2012;59(2):128-133.
- Roelofs áPD, Deyo áRA, Koes áBW, et al. Nonsteroidal anti-inflammatory drugs for low back pain. Spine. 2008;33(16):1766-1774.
- Waterman áBR, Belmont áPJ Jr, Schoenfeld áAJ. Low back pain in the United States: Incidence and risk factors for presentation in the emergency setting. Spine J. 2012;12(1):63-70.
Codes
ICD9
- 724.2 Lumbago
- 724.3 Sciatica
- 724.5 Backache, unspecified
ICD10
- M54.5 Low back pain
- M54.9 Dorsalgia, unspecified
- M54.30 Sciatica, unspecified side
- M54.40 Lumbago with sciatica, unspecified side
- M54.31 Sciatica, right side
- M54.3 Sciatica
- M54.41 Lumbago with sciatica, right side
- M54.42 Lumbago with sciatica, left side
- M54.4 Lumbago with sciatica
SNOMED
- 161891005 backache (finding)
- 279039007 low back pain (finding)
- 278862001 acute low back pain (finding)
- 278860009 chronic low back pain (finding)
- 23056005 Sciatica (disorder)