What clinical sign is used to evaluate rib pain associated with kidney issues?

Costovertebral angle tenderness is a clinical sign specifically used to evaluate rib pain that may be associated with kidney issues. This test involves gently tapping the area over the lower ribs on the back, where the kidneys are located. A positive response, which manifests as pain or tenderness upon palpation, can indicate potential kidney pathology, such as a urinary tract infection, pyelonephritis, or other kidney-related conditions. Identifying this tenderness is crucial in assessing the renal status of the patient and directs further diagnostic investigations if indicated.

The other options mentioned do not serve the same purpose in evaluating kidney-related rib pain. For instance, cervical instability checks are focused on the cervical spine, palpation of the abdomen assesses abdominal organs primarily, and spinal alignment tests are more concerned with structural issues within the spine rather than kidney function or abnormalities.