Spondylolysis

Procedure

Patient stands on one leg, lifts the other knee forward, then leans back into lumbar extension. Repeat standing on the other leg.

Positive Finding

Reproduction of the familiar low back pain, often on the side of the standing leg.

Sensitivity / Specificity

Reference: Masci L, Pike J, Malara F, Phillips B, Bennell K, Brukner P. Use of the one-legged hyperextension test and magnetic resonance imaging in the diagnosis of active spondylolysis. Br J Sports Med. 2006;40(11):940-6; discussion 946.

Interpretation

Widely taught for suspected pars stress injury in young athletes, but the test performs poorly and a negative result must not be used to rule spondylolysis out. In a young athlete with activity-related low back pain made worse by extension, refer for imaging when a stress injury is suspected. From 71 young athletes with low back pain referred for suspected spondylolysis (Masci 2006). Bone scan with SPECT was the reference: 34–38 had active spondylolysis and 33–37 did not, depending on the side. The authors concluded the test is neither sensitive nor specific and should not be used to rule spondylolysis out. Specificity here is calculated from the paper's own tables of patient counts; its summary table prints 67.6% for the left side, which does not match those counts (12 of 37 = 32%).

Procedure

Patient prone. Ask the patient to push up on the hands into a press-up, or stand and lean back, and note any pain and where it is felt.

Positive Finding

Reproduction of the familiar low back pain during extension.

Interpretation

Extension loads the pars interarticularis, but it also loads the facet joints and other posterior structures, so pain with extension is common in many back problems. The history (young athlete, repeated extension and rotation sports, pain made worse by extension) is more informative than this test. Two systematic reviews (Alqarni 2015; Grødahl 2016) found that the only physical test studied for spondylolysis is the one-legged hyperextension (stork) test, and it performed poorly. No study of this test was found, so no figure is shown.

Procedure

Patient prone or standing leaning slightly forward. Tap gently over each lumbar spinous process with a fingertip or reflex hammer.

Positive Finding

Sharp, localised pain at one level, most often L5.

Interpretation

Focal bony tenderness raises concern for a bony injury such as a stress fracture. It is a simple screen, not a diagnosis; imaging confirms. In an older patient, midline bony tenderness with night pain or weight loss needs medical assessment.

Procedure

Patient prone. Stabilise the pelvis and lift the straight leg into hip extension, or ask the patient to lift it actively. Compare both sides.

Positive Finding

Reproduction of the familiar low back pain on the tested side.

Interpretation

Loads the lower lumbar spine in extension, but also the sacroiliac joint and hip, so a positive result does not point to one structure. It is not a validated test for spondylolysis. (The Hirschberg test is an eye test; the name has been corrected.)

Procedure

Patient standing. Guide the lumbar spine into extension with side-bending and rotation towards the painful side, adding gentle overpressure through the shoulders if tolerated. Repeat to the other side.

Positive Finding

Reproduction of the familiar one-sided low back pain.

Interpretation

Loads the posterior structures on one side, including the pars and the facet joint. It shows which movement provokes the pain but cannot identify a pars defect; imaging is needed when a stress injury is suspected.