A 40-year-old nurse with back pain worsened by sitting and radiating down the thigh is most consistent with which condition?

• A. Acute lumbar strain
• B. Sciatica
• C. Ovarian torsion
• D. Pyelonephritis

Answer: (B)

Radicular pain from sciatic nerve irritation is the key idea. When back pain radiates down the thigh, it points to nerve root involvement rather than a simple muscle strain. Sciatica occurs when the sciatic nerve or its roots are compressed or irritated (for example from a herniated disc), producing pain that travels along the leg and often worsens with sitting because sitting increases intradiscal pressure and nerve compression.

Localized acute lumbar strain usually stays in the back with muscle spasm and lacks the leg radiation. Ovarian torsion presents with acute pelvic pain and systemic symptoms, not a back radicular pattern. Pyelonephritis involves fever, urinary symptoms, and flank pain rather than leg radiation.