Effect of sagittal shape on proximal junctional kyphosis following thoracopelvic corrective fusion for adult spinal deformity: postoperative inflection vertebra cranial to T12 is a significant risk factor

Relook into the Risk Factors of Proximal Junctional Kyphosis in Early Onset Scoliosis Patients: Does the Location of Upper Instrumented Vertebra in Relation to the Sagittal Apex Matter?

“… 24 In previous studies, some authors investigated the apices of the sagittal curvature to assess the sagittal morphological shape of the spine. 25 , 26 , 27 , 28 Jakinapally et al . 25 reported that the IV is significantly cranial and posterior in the PJK group in adult spinal deformity.…”

“… 25 , 26 , 27 , 28 Jakinapally et al . 25 reported that the IV is significantly cranial and posterior in the PJK group in adult spinal deformity. Investigation of the location of UIV, apex and IV is a simple method of evaluating the spinal curvature.…”

“…Sagittal plane also has important reference significance for the selection of UIV. 25 , 33 Admittedly, it is not possible for every EOS patient to have an UIV as high as T2 or above because minimizing the interference of GR surgery to the non‐deformity area is essential. Therefore, this study provides a relatively individualized UIV selection scheme.…”

“…At the same time, IV acts as an important parameter to classify the normal sagittal shapes of spinopelvic organization, since it represents the actual location where the kyphotic curve turns in the lordotic curve 24 . In previous studies, some authors investigated the apices of the sagittal curvature to assess the sagittal morphological shape of the spine 25–28 . Jakinapally et al 25 .…”

“…When choosing the location of UIV, we need to consider not only the need of correction of coronal deformity, but also the location relationship between UIV and apex. Sagittal plane also has important reference significance for the selection of UIV 25,33 . Admittedly, it is not possible for every EOS patient to have an UIV as high as T2 or above because minimizing the interference of GR surgery to the non‐deformity area is essential.…”