Retrospective Image Analysis of Degenerative Lumbar Disease Patients

All surgeries were performed by a senior surgeon using a traditional midline approach. Stability-preserving lumbar decompression with facet joint undercutting was performed to preserve the facet joints as much as possible. In cases of severe stenosis, a bilateral partial facetectomy (\< 25%) was performed for adequate decompression. Posterior tension of the supra- and inter-spinous ligaments was preserved at the most cranial level. Patients were encouraged to ambulate after drain removal and wear a soft lumbar orthosis for at least 3 months after the operation.