Knee Pain Is Not Always the Knee.

» Lumbar spine pathology is a known cause of referred pain to the lower extremities and should be investigated as a possible source of knee pain, especially with patients in their sixth decade.» While primary knee pathology is common, spinal pathology should always be considered in older patients presenting with knee pain, especially in atraumatic cases where knee imaging does not correlate with complaints or examination findings.» Lumbar (L) 3-4 pathology is most commonly affected in referred knee pain, with the 2 most common pathologies being spinal stenosis and disc herniation.» If knee radiographs do not demonstrate major pathology that correlates with a patient's history and examination, a thorough spine examination should then be performed with attention paid to patellar tendon reflex, quadriceps muscle strength, and any loss of sensation, as these can be hallmarks of L3-4 pathology.