Fig. 3

A 66-year-old, male, patient complained of lower back pain and pain in bilateral lower limbs for 2 years and aggravation for 7 months. There was spinal canal stenosis at L3–L5, and the patient received PLIF at L3–L5. a–d X-ray for the lumbar spine in the anteroposterior/lateral and flexion/extension views before surgery; intervertebral mobility 4.3° at L2-L3. e–g Lumbar MRI scan before surgery indicated spinal canal stenosis at L3–L4 and L4–L5, with modified Pfirrmann grade of disc 3 at L2–L3; h–k X-ray for the lumbar spine in the anteroposterior/lateral and flexion/extension views at 36 months after surgery. The intervertebral mobility at L2–L3 was increased significantly to 7.3° after surgery. l MRI scan at 36 months after surgery indicated that the modified Pfirrmann grade of disc was increased to grade 4 at L2–L3