X-Stop: foot drop

Background contextThe X-Stop (Kyphon, Sunnyvale, CA), a device implanted between adjacent lumbar spinous processes at one or two levels particularly in the geriatric population, theoretically decompresses the spinal canal by reversing the lordosis.PurposeThe X-Stop relieves the symptoms of lumbar stenosis.Study design/settingA case report from the United States.Patient sampleA case report focusing on how X-Stop placement resulted in a bilateral foot drop in an 84-year-old patient, which was relieved 9 months later with laminectomy.Outcome measuresThe patient's outcome was based on the neurological examination.MethodsAn 84-year-old male with lumbar neurogenic claudication/radiculopathy, exhibited magnetic resonance (MR)-documented L4–L5 lumbar stenosis and Grade I degenerative spondylolisthesis. At an outside institution, an L4–L5 X-Stop was placed; he immediately developed a bilateral foot drop. Three months later, the X-Stop extruded, and was removed; his foot drop remained unchanged. Nine months after the original surgery, based on new MR/computed tomography (CT) documented severe (L2–L3, L4–L5), moderate (L1–L2, L3–L4, L5–S1) stenosis, and the L4–L5 Grade I degenerative spondylolisthesis, the second surgeon performed an L1–S1 laminectomy with L4–L5 noninstrumented fusion.ResultsPostoperatively, the patient's bilateral foot drop largely resolved.ConclusionsPlacing the X-Stop device at severely stenotic levels, particularly when accompanied by degenerative spondylolisthesis, may contribute to significant postoperative neurological sequelae in geriatric patients. For those with limited comorbidities, operative decompression may prove the safer alternative.