Lower Limb Arterial Disease

The goal of this interventional study is to evaluate the rate of existing lower limb peripheral artery disease (PAD) in patients with surgically lumbar spinal stenosis (LSS). PAD and LSS can present similar symptoms and it can be difficult to diagnose PAD using conventional methods, depending on the location of the arterial disease. The main questions it aims to answer are : * What's the prevalence of PAD in LSS patients? * Which exam among routine tools is the most accurate to diagnose PAD in this population? Around their surgery for LSS (a few weeks before or after), participants will be included in a vascular medicine service. After checking of eligibility criteria, they will undergo a contrast-enhanced CT scan for the diagnosis of PAD and various routine diagnostic tests: Doppler ultrasound, treadmill tests, pressure index, pulse palpation.