Surgical Treatment of Spinal Deformity With Sagittal Imbalance Using Patient-specific Rods: A Multicenter, Controlled, Double- Blind Randomized Trial: The PROFILE Study

Lumbar degenerative diseases (LDD) are an increasingly common condition affecting millions of patients worldwide. LDD can impact not only function, but can also become markedly disabling and cause severe chronic pain. Recent studies support the idea that analysis of sagittal balance is a crucial keypoint to optimize the management of lumbar degenerative diseases, especially when spinal instrumentation is intended. The first treatment of these pathologies is a medical treatment (medications, physical therapy and exercise). Surgical treatment is frequently necessary if the symptoms worsen and is generally a posterior spinal fusion with instrumentation (screws, hooks and rods) and bone graft. Basic principle of the surgery is to realign the spine along the rod. Despite documented techniques for surgical planning, it appears that a significant number of patients are ultimately under-corrected after surgery Realignment failure has not only been associated with poor functional outcome but also major complications, such as pseudoarthrosis and rod breakage, which often results in additional surgical procedures. From a pragmatic point of view, there are two main reasons for realignment failure: poor surgical planning and poor execution. One of the assumptions is that perioperative manual bending of the rod may not always allow the surgeon to restore the sagittal parameters as intended. A new concept of patient-specific rod (PSR) is now being proposed by a French manufacturer in order to enable an optimal correction and surgical stabilization of the spine. PSR are designed to fit with the patient's unique sagittal spine profile and with surgeons' surgical planning. However, no relevant clinical data is currently available to support the expected medical benefit of this new technology. The objective of the study is therefore to carry out a study hypothesizing that the use of PSR could improve the percentage of patients whose sagittal profile is optimally corrected after s