Back pain (red flags)

General

Although there are many red flags of back pain on history and physical, meta-analysis has shown the following to be predictive of fracture or malignancy:

Back Pain Risk factors and probability of Fracture or Malignancy

Factor	Post Test Probability (95%CI)
Older Age (>65yo)	9% (3-25%)
Prolonged corticosteroid	33% (10-67%)
Severe trauma	11% (8-16%)
Presence of contusion or abrasion	62% (49-74%)
Multiple red flags	90% (34-99%)
History of malignancy	33% (22-46%)

Red Flag Symptoms of Low Back Pain

Symptoms	Corresponding Pathology
Age under 18 years	Congenital abnormality
Age over 50 years	Fracture, malignancy
Anticoagulant use	Spinal hematoma
Fever	Infection, malignancy
Genitourinary issues including urinary retention/incontinence or sexual dysfunction	Cauda equina syndrome
Immunocompromised	Fracture, infection
IV drug use	Infection
Recent spinal surgery or epidural injection	Infection, spinal hematoma
Trauma	Fracture, spinal hematoma

Red Flag Signs of Low Back Pain

Signs	Corresponding Pathology
Reduced anal sphincter tone	Cauda equina syndrome
Hyperreflexia	Acute cord compression
Hyporeflexia/areflexia	Cauda equina syndrome
Lower extremity muscle weakness	Acute cord compression or Cauda equina syndrome
Saddle paresthesia/anesthesia	Cauda equina syndrome
Absent or decreased bulbocavernosus reflex	Cauda equina syndrome

History

• Pain >6wk (tumor, infection)
• Age >50 or <18 (tumor, congenital anomaly)
• History of trauma
• History of IVDU
• History of cancer
• History of sciatica
• Neurological complaints (paresthesias, anesthesia, weakness)
• Urinary retention
• Incontinence of bowel/bladder
• Night pain
• Unremitting pain, even when supine
• Fever, chills, night sweats
• Anticoagulants/coagulopathy

Physical Exam

• Fever
• Patient writhing in pain
• Anal sphincter laxity
• Perianal/perineal sensory loss (Saddle Anesthesia)
• Palpable bladder post voiding or abnormal post void residual
• Point vertebral tenderness
• Neurological deficits
• Positive straight leg raise

Specific Condition Red Flags

Cancer Related

• History of back pain
• Weight loss >10kg in 6mo
• Age >50 or <18
• No improvement despite therapy
• Pain for >4-6wks
• Night pain
• Pain worse at rest
• Vertebral tenderness
• Multiple nerve roots affected

Infection Related

• Persistent fever
• History of IVDA
• Recent infection
• Immunocompromised state
  • HIV
  • Systemic corticosteroids
  • Transplant
  • DM

Cauda Equina

• Incontinence or retention
• Saddle anesthesia
• Decreased anal sphincter tone
• Bilateral lower extremity weakness or numbness
• Neurologic deficit

Herniated Disc

• Muscle Weakness
• Radiation of pain
• Footdrop

Vertebral Fracture

• Prolonged use of corticosteroids
• History of osteoporosis
• Age>70
• Mild trauma in age >50yr
• Significant trauma in any age
• Bony tenderness

AAA/Aortic Dissection

• Risk factors for PVD
• Pulsating mass
• Pain at rest or at night
• Age >60yrs

See Also

• Lower back pain