Prospective evaluation of spinal canal remodeling and clinical recovery after MIS-TLIF and open TLIF: Correlation of clinical and functional outcome with improvement in spinal canal diameter

The study will include consecutive adult patients (Greater than 18 years) diagnosed with degenerative lumbar spondylolisthesis and moderate-to-severe central canal stenosis on MRI, whose surgeons have already planned surgery using either MIS-TLIF or open TLIF. Consecutive enrolment during a 12-month window will reduce selection bias and reflect real-world practice.

Each patient will be followed for 12 months after surgery, allowing analysis of early recovery, radiological canal remodeling, and postoperative complications. All surgeries will be performed at a single centre by experienced surgeons using standardized operative steps (decompression, discectomy, cage insertion, and pedicle-screw fixation), ensuring uniformity of technique so that any differences observed later can be attributed mainly to the type of surgical approach rather than surgeon variability.