Surgery for degenerative spondylolisthesis requires decompression of the narrow lumbar canal and fixation by osteosynthesis-arthrodesis. Conventional surgery is done through the open route. For 10-15 years, minimally invasive techniques have been established, allowing faster postoperative recovery for the patient. The downside to these techniques is the use of intraoperative fluoroscopy. This is why surgical navigation systems have been developed, allowing safe positioning of implants (pedicle screws). A new process (augmented reality navigation) has been tested in vitro and applied in open surgery. The HUS were the first establishment to apply this new method in minimally invasive surgery in a hybrid room of surgery and interventional radiology.

Inclusion criteria:

• Major subject (≥18 years old)
• Subject operated at the HUS between March and December 2019
• Subject with a surgical indication for arthrodesis and decompression of the lumbar canal for degenerative spondylolisthesis L3-L4 or L4-L5
• Subject not having expressed his opposition, after information, to the reuse of his data for the purposes of this research.

Exclusion criteria:

• Subject having expressed opposition to participating in the study
• Subject under guardianship or guardianship
• Subject under safeguard of justice

Major subject with a surgical indication for arthrodesis and decompression of the lumbar canal for degenerative spondylolisthesis L3-L4 or L4-L5