Are the radicular symptoms coming from the piriformis?

My mom got a random injury bowling a couple weeks ago, and I just got the chance to evaluate her. This prompted me to go back to my OCS study materials and share what I learned:

Many patients with the "sciatica" symptom distribution may begin by seeking treatment for their spine, and the prevalence of structural findings with spinal MRI may seem to confirm these hypotheses. However, when other elements of the exam seem to point elsewhere, here are a couple of tests that may reveal involvement of the piriformis muscle:

Active Piriformis test: with patient in side-lying, the PT resists the "clamshell" action of hip abduction and external rotation. The patient plant the foot on the table and rotates into PT resistance. This test causes contraction of the deep external rotators which can potentially recreate localized or radicular symptoms (Sensitivity 78%, Specificity 80%).

Seated Piriformis test: with patient in sitting, the PT passively holds the knee in extension and moves the hip into adduction and internal rotation. This test elongates the deep external rotators which can potentially compress the sciatic nerve to recreate localized or radicular symptoms (Sensitivity 52%, Specificity 90%). Ensure that the patient maintains upright posture, as this testing position has a lot of similarities with the slump test for neural tension.

Best diagnostic accuracy (compared to endoscopic findings) was achieved when using the above two tests in a cluster (Sensitivity 91%, Specificity 80%).

Positive tests do not rule out the contribution of the lumbar spine/related structures to patient symptoms. Clinically, a sensitized nerve is often easily provoked with special testing at a variety of sites along the nerve distribution. The results of these tests are likely most useful in helping us further identify the symptom pattern, so as to better educate our patients about potential aggravating and easing positions. The sensation provoked in the test can also help guide patients to recognize the difference between the sensation of a muscular stretch, muscle activation, and nerve irritation. All 3 can be described as a "burn" but a provocative test may give the patient the context to begin to differentiate.

Martin HD, Kivlan BR, Palmer IJ, Martin RL. Diagnostic accuracy of clinical tests for sciatic nerve entrapment in the gluteal region. Knee Surgery, Sports Traumatology, Arthroscopy. 2014 Apr;22(4):882-8.