Lumbar stenosis (LSS) is the most frequent degenerative lumbar disease and is the most frequent indication for spinal surgery. When non-invasive treatments fail, decompression surgery is the gold standard therapy for the majority of patients and generally improves symptoms.

However, few studies have investigated the improvement in posture (radiological parameters) after surgery. In lumbar stenosis, patients may present a forward leaning posture (to relieve pain), which is responsible for sagittal imbalance.

The aim of this prospective study was to evaluate the repercussions of decompression surgery on sagittal balance and to compare these with aux clinical results. investigators included patients operated on for isolated lumbar canal stenosis.

Inclusion Criteria:

1. Symptoms and signs of neurogenic claudication and radiological signs of central lumbar stenosis;
2. Patients undergoing open decompression surgery ≤ 3 levels,
3. All patients with symptoms that did not respond to at least 3 months of non-invasive treatment.

Exclusion Criteria:

Patients were excluded from the study if they had one or several of the following clinical and/or radiological criteria:

1. spondylolisthesis (disc slip > 5 mm),
2. criteria showing instability (variation of > 10° in the angle formed by the vertebral endplates on dynamic images).
3. scoliosis (Cobb angle > 20 °).
4. Patients lost to follow-up were excluded.

consecutive patients who underwent open decompression surgery (laminotomy) were prospectively included in this study