Chapter 24: Acute Low Back Pain Assessment

The text explains the importance of a focused history to screen for "red flags" including fever, recent trauma, unexplained weight loss, history of cancer, and prolonged corticosteroid use, while also assessing for neurological emergencies indicated by saddle anesthesia or loss of bowel and bladder control. It differentiates between mechanical etiologies like musculoligamentous strain and diskogenic pain versus neurogenic causes like sciatica, which presents with sharp radiation down the leg, and nonspinal causes such as abdominal aortic aneurysms, pyelonephritis, or gallbladder disease. The physical examination section details critical assessments including gait analysis, inspection for spinal deformities like scoliosis or kyphosis, and specific maneuvers such as the Straight Leg Raising (SLR) test to evaluate for herniated disks and nerve root tension at L5 and S1. Additional diagnostic tests described include the FABER maneuver for sacroiliac joint pathology and the modified Schober test to measure lumbar mobility, with specific normal and abnormal values provided for clinical interpretation. The summary covers age-related differential diagnoses, noting that adolescents are more likely to suffer from spondylolysis or Scheuermann disease, whereas adults over 50 face higher risks of spinal stenosis, osteoporotic fractures, and malignancy. Furthermore, evidence-based guidelines regarding diagnostic imaging are reviewed, stressing that routine radiography or MRI is generally unnecessary in the first four weeks unless red flags or significant neurological deficits are present. Finally, the chapter addresses systemic and inflammatory causes such as ankylosing spondylitis and vertebral osteomyelitis, as well as psychogenic factors that may influence the patient's perception of pain and disability.