Dynamics of the sagittal profile of the spine after isolated decompression of intracanal neurovascular formations in degenerative lumbar stenosis: protocol of a prospective multicenter study**

Objective. To determine the impact of isolated decompression of intracanal neurovascular structures of the spine on sagittal balance in patients with degenerative lumbar stenosis. Study registration number: NCT07139938, clinicaltrials.gov.

Material and Methods. Adult patients with neurological and/or pain syndromes caused by degenerative lumbar stenosis confirmed by MRI will be enrolled in research centers across Russia. All patients will undergo isolated decompression of neurovascular structures without the use of any implants. The dynamics of sagittal balance parameters will be assessed at 3 and 12 months after surgery by comparing with preoperative data. The sample size was calculated in accordance with the hypothesis of non-inferiority. The study aims to enroll 165 patients. Patient recruitment will take 12 months, and the total duration of the study will be approximately 2 years.

Anticipated results. This study will provide valuable information on the potential for spontaneous correction of sagittal spinal parameters following isolated decompression without the use of implants.

** Dear colleagues! We invite you to participate in a multicenter prospective study of spontaneous correction of spinal sagittal balance in patients with degenerative spinal pathology after isolated decompression. The person responsible for inclusion in the multicenter study is Alexandr Vladimirovich Krutko, MD, PhD (National Medical Research Center of Traumatology and Orthopedics n.a. N.N. Priorov, Moscow), e-mail: KrutkoAV@cito-priorov.ru.

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