The impact of Roussouly sagittal profile changes on postoperative outcomes

Area of Science:

• Spine surgery
• Orthopedics
• Radiographic analysis

Background:

• Adult spinal deformity (ASD) treatment involves complex surgical planning.
• The Roussouly classification categorizes sagittal spinal alignment based on pelvic parameters.
• Postoperative changes in sagittal alignment can affect patient outcomes.

Purpose of the Study:

• To investigate the relationship between postoperative Roussouly sagittal profile changes and patient outcomes in ASD.
• To identify specific Roussouly type changes associated with adverse events or functional improvements.

Main Methods:

• Retrospective review of 525 ASD patients with 2-year follow-up data.
• Stratification of patients by baseline and postoperative Roussouly curve types.
• Statistical analysis of Roussouly type changes and their association with complications and minimum clinically important differences (MCIDs).

Main Results:

• 39% of patients experienced a change in Roussouly shape postoperatively.
• Specific changes (e.g., R1 to R2, R2 to R4, R3 to R4) increased the risk of proximal junctional kyphosis/failure.
• R4 to R3 changes showed the highest risk of mechanical complications.
• R1 to R2 changes were linked to better Oswestry Disability Index outcomes at 6 weeks.

Conclusions:

• A significant number of patients change their Roussouly type postoperatively, even if initially matched.
• Postoperative sagittal profile shifts influence patient outcomes, including complication risks and functional recovery.
• Accounting for potential Roussouly shape changes is essential for effective ASD surgical planning.