Differential Diagnosis for Left Low Back Sharp Pain

• Single most likely diagnosis
  • Musculoskeletal strain: This is the most common cause of acute low back pain, often resulting from lifting, bending, or sudden movement. The sharp pain can be attributed to the pulling or tearing of muscles or ligaments in the lower back.
• Other Likely diagnoses
  • Lumbar disc herniation: A herniated disc can cause sharp pain in the lower back, especially if it compresses or irritates nearby nerves. The pain can be localized to one side, depending on the disc affected.
  • Degenerative disc disease: As discs degenerate, they can cause sharp pains due to the reduction in disc height and the potential for nerve irritation.
  • Spondylosis or spondylolisthesis: These conditions involve defects in the vertebrae or the slipping of one vertebra over another, which can cause sharp pain, especially if nerves are compressed.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
  • Abdominal aortic aneurysm: Although less common, an abdominal aortic aneurysm can present with severe, sharp back pain and is a medical emergency requiring immediate attention.
  • Kidney stones: Nephrolithiasis can cause severe, sharp flank pain that may radiate to the lower back, and while not typically deadly, it requires prompt medical evaluation.
  • Spinal infection (e.g., osteomyelitis, discitis): Infections of the spine can cause severe back pain and are medical emergencies due to the potential for serious complications, including paralysis and death.
  • Cancer with metastasis to the spine: Although rare, cancer that has spread to the spine can cause back pain and is critical to diagnose early for appropriate management.
• Rare diagnoses
  • Osteoporotic compression fracture: While more common in individuals with known osteoporosis, a compression fracture can cause sudden, sharp back pain and is a significant concern in the elderly or those with osteoporosis risk factors.
  • Spinal epidural abscess: A collection of pus in the epidural space surrounding the spinal cord can cause severe back pain, fever, and neurological deficits, requiring urgent medical attention.
  • Pott's disease (spinal tuberculosis): A rare condition in many parts of the world, spinal TB can cause back pain, fever, and neurological symptoms, and its diagnosis is crucial for appropriate antibiotic treatment.