The predictive power of the Roussouly classification on mechanical complications after surgery for adult spinal deformity: systematic review and meta-analysis

Marven Aoun; Mohammad Daher; Alan H Daniels; Gaby Kreichati; Khalil Kharrat; Amer Sebaaly

doi:10.1007/s00586-024-08596-w

The predictive power of the Roussouly classification on mechanical complications after surgery for adult spinal deformity: systematic review and meta-analysis

Eur Spine J. 2024 Dec 11. doi: 10.1007/s00586-024-08596-w. Online ahead of print.

Authors

Marven Aoun¹, Mohammad Daher^{1

2}, Alan H Daniels², Gaby Kreichati¹, Khalil Kharrat¹, Amer Sebaaly^{3

4}

Affiliations

¹ Department of Orthopedic Surgery Spine Unit, Hotel Dieu de France Hospital, Alfred Naccache Boulevard, Beirut, Lebanon.
² Department of Orthopedic Surgery, Brown University, Providence, RI, 02906, USA.
³ Department of Orthopedic Surgery Spine Unit, Hotel Dieu de France Hospital, Alfred Naccache Boulevard, Beirut, Lebanon. amersebaaly@hotmail.com.
⁴ School of Medicine, Saint Joseph University, Beirut, Lebanon. amersebaaly@hotmail.com.

PMID: 39663226
DOI: 10.1007/s00586-024-08596-w

Abstract

Background: With the increasing prevalence of adult spinal deformity (ASD) in the aging population, the need for corrective surgery has surged, highlighting the importance of preventing mechanical complications (MC) such as junctional kyphosis/failure and rod breakage. The Roussouly classification, which categorizes natural variations in spinal posture, may hold predictive value in assessing the risk of these complications, as it guides the restoration of sagittal alignment based on a patient's preoperative spinal shape.

Methods: PubMed, Cochrane, and Google Scholar (pages 1-20) were searched through August 2024 to find articles comparing the incidence of mechanical complications between patients who were matched and mismatched to their ideal Roussouly shape after surgery for ASD. Extracted data consisted of the risk of mechanical complications, and the risk of reoperations.

Results: 10 retrospective studies were included in this meta-analysis, with 1454 patients divided into 2 groups, the first group matching Roussouly classification (716 patients, 49%) and the second unmatched (738 patients, 51%). A 5-times lower rate of mechanical complication (Odds-Ratio = 0.22; 95% CI: 0.12-0.41, p < 0.001) was found in the matched group at an average follow-up of 3.6 years. Furthermore, when examining specific mechanical complications, there were higher rates of both PJK (Odds-Ratio = 1.59; 95% CI: 1.07-2.38, p = 0.02) and rod breakages (Odds-Ratio = 1.75; 95% CI: 1.15-2.66, p = 0.01) in the unmatched group. However, no difference in the rate of reoperations was observed between the two groups (Odds-Ratio = 0.48; 95% CI: 0.18-1.28, p = 0.14).

Conclusion: Matching patients to their ideal Roussouly type in adult spinal deformity surgery significantly reduces mechanical complications making it a secure and efficient method. Future studies should compare the Roussouly classification to other alignment models to determine optimal alignment for ASD correction surgery.

Level of evidence: III.

Keywords: Mechanical complciations; Proximal junctional kyphosis; Rod breakage; Roussouly; Sagittal profile.

Publication types

Review