Spondylolisthesis

A 15-year-old male presents with chronic low back pain. Lateral radiographs of the lumbar spine show anterior displacement of L5 over S1, with the posterior aspect of L5 covering 20% of the superior endplate of S1. According to Meyerding's classification, what grade of spondylolisthesis is this?

A 12-year-old gymnast presents with persistent low back pain exacerbated by hyperextension. Radiographs reveal an anterior slip of L5 on S1. Which of the following is the most likely underlying pathology in this patient?

A 60-year-old male with a known history of L4-L5 degenerative spondylolisthesis presents to the emergency department with acute onset bilateral leg weakness, saddle anesthesia, and urinary retention. Which of the following is the most appropriate immediate management step?

Which specific radiographic view is most effective for visualizing a pars interarticularis defect in a patient suspected of having isthmic spondylolisthesis?

A 45-year-old male with L5-S1 degenerative spondylolisthesis (Grade II) has failed 6 months of conservative management, including physical therapy, NSAIDs, and epidural injections. He continues to experience severe radicular pain in his left leg, significantly impacting his quality of life. Neurological examination reveals mild weakness in the left extensor hallucis longus. What is the most appropriate next step in management?