The restoration of lumbar lordosis is mandatory during lumbar fusion surgery for degenerative disc disease, since not restoring lumbar lordosis adequately may adversely affect surgical outcomes and the patient's quality of life in the follow-up. Revision surgery to restore segmental lordosis at the level of previous spinal fusion is extremely difficult to do and its performance is usually inferior to that of primary surgery. Need to provide a surgical technique to restore segmental lordosis via a posterior approach, which is especially important after failed previous fusion at the same lumbar level.

Inclusion Criteria:

• 1. Over 18 years' old;
• 2. Lumbar back pain with / without radicular leg pain (with / without neurological deficit) with / without neurogenic claudication, symptoms persisting for at least 3 months prior to surgery;
• 3. 1) Failed back lumbar fusion surgery at the same level or on an adjacent segment or 2) Symptomatic discopathy with loss of segmental lordosis at one of the levels L3-L4, L4-L5 or L5-S1, confirmed by MRI и Rg, with/without degenerative stenosis/spondylolisthesis
• 4. Need for a planned surgical procedure with a major extent of segmental lordosis restoration (more than 10°);
• 5. Given written informed consent;
• 6. Able and agree to fully comply with the clinical protocol and willing to adhere to follow-up schedule and requirements

Exclusion Criteria:

• 1. Interbody implants previously placed via non-posterior approach at the level of surgery (which cannot be removed through the posterior approach);
• 2. Complete interbody fusion after previous surgery at the level of surgery;
• 3. HU values of lumbar body vertebrae less than 120 HU;
• 4. Any contraindication or inability to undergo baseline and/or follow up MRI, CT or X-ray as required per protocol;
• 5. Back or non-radicular pain of unknown etiology;
• 6. History or presence of any other major neurological disease or condition that may interfere with the study assessments;
• 7. Previous enrollment in this study, current enrollment or plans to be enrolled in another study (in parallel to this study).