Restoring Segmental Lumbar Lordosis After Failed Previous Fusion at the Same 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 stud…