Clinical and Radiological Outcomes of Transverse Process Hooks Versus Pedicle Screws at the Upper Instrumented Vertebra in Adult Spinal Deformity Patients Undergoing Three-Column Osteotomy: A Retrospective Comparative Study Publisher Pubmed



Rostami M ; Bagherzadeh S ; Moghadam N ; Roohollahi F ; Cuello CC ; Kumar J ; Greenberg M ; Alikhani P
Source: Clinical Neurology and Neurosurgery Published:2026

Abstract

Background Proximal junctional kyphosis (PJK) and failure (PJF) are critical complications following adult spinal deformity (ASD) surgery. The use of transverse process hooks (TPH) at the upper instrumented vertebra (UIV) has been proposed as a “soft-landing” alternative to rigid pedicle screws (PS), but it remains controversial whether the implant choice or the magnitude of correction is the primary driver of PJK. This study aimed to determine if TPH fixation independently reduces the risk of junctional complications compared to PS in high-risk ASD patients undergoing three-column osteotomies (3CO). Methods A retrospective review of 132 ASD patients undergoing 3CO with spinopelvic fixation (70 TPH, 62 PS) and a minimum 2-year follow-up was performed. Demographics, surgical data, radiographic parameters, complications, and patient-reported outcomes (PROMs) were compared. A multivariate logistic regression was performed to identify independent predictors of PJK, controlling for patient factors and postoperative alignment. Results The TPH group had significantly lower rates of PJK (21.4 % vs. 37.0 %, p = 0.04) and PJF (17.1 % vs. 32.2 %, p = 0.04). While overall reoperation rates were similar (41.4 % vs. 45.1 %, p = 0.66), the reasons for revision differed: symptomatic PJF was the primary indication in the PS group, versus other mechanical failures (e.g., pseudarthrosis, rod fracture) in the TPH group. Crucially, multivariate logistic regression identified TPH use as an independent protective factor against PJK (Adjusted Odds Ratio = 0.329, p = 0.020), while postoperative alignment parameters, such as SVA and LL, were not significant predictors. PROMs were similar between groups. Conclusions In complex ASD surgery requiring 3CO, TPH fixation at the UIV is an independent protective factor against PJK. While TPH significantly reduces the risk of junctional failure, it appears to transfer mechanical stress elsewhere, leading to different modes of late construct failure without changing the overall reoperation rate. Clinical Relevance This study provides strong evidence that TPH at the UIV mitigates the risk of PJK independent of the magnitude of sagittal correction. This supports its use as a valuable strategy to reduce proximal junctional complications, though surgeons must remain vigilant for other potential modes of mechanical failure. Level of Evidence Level III, retrospective comparative study. © 2025 Elsevier B.V.