What test should be performed to assess for a herniated disc in a patient with low back pain?

The straight leg-raise test is the appropriate assessment tool for evaluating a herniated disc in a patient experiencing low back pain. This test is performed by having the patient lie supine while the examiner lifts the patient's leg while keeping the knee straight. If lifting the leg reproduces the patient's pain, particularly down the back of the leg, it is indicative of nerve root irritation or compression, which is often associated with herniated discs.

This test effectively highlights possible nerve root involvement and can help differentiate the source of the pain as originating from the lumbar spine rather than from other structures. The specificity of this test for detecting issues such as a herniated disc makes it a cornerstone in the physical examination of patients with low back pain.

In contrast, spinal extension and flexion tests focus on the mobility and stability of the spine rather than directly assessing nerve root function, making them less reliable indicators of a herniated disc. The McMurray test, on the other hand, is primarily utilized for assessing meniscal injuries in the knee, which is unrelated to evaluating lumbar spine conditions.