Lippincott Williams & Wilkins

Development of L3 antero- or retrolisthesis more than 3 mm; OR. Decrease in L3-4 disc height of more than 3 mm; OR. Intervertebral angle at flexion smaller than -5°. Clinical (symptomatic) deterioration of L3-4 defined by presence of all of the following: Decrease of 4 or more points on the JOA scale AND ................
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