142 - Proximity of endplate on the upper instrumented vertebra(UIV) using cortical bone trajectory screws can be a risk factor for early onset postoperative radiologic adjacent segment disease

Saturday, June 3, 2023

12:02 PM – 12:04 PM

Location: Salons 13-15

Presenting Author (Person doing the Podium Present(s)

JI WON KWON, n/a

Assistant professor
Yonsei university college of medicine
강서구, Seoul-t'ukpyolsi, Republic of Korea

Co-Author(s)

YP

Yung Park

Professor
Department of Orthopedic Surgery, National Health Insurance Service Ilsan Hospital, Goyang, Republic of Korea, Kyonggi-do, Republic of Korea
NK

Namhoo Kim

Assistant professor
Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea, Republic of Korea
Sp

Subri park

Assistant professor
Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea, Seoul-t'ukpyolsi, Republic of Korea
JS

Jae-Won Shin

Assistant professor
Department of Orthopedic Surgery, National Health Insurance Service Ilsan Hospital, Goyang, Republic of Korea, Seoul-t'ukpyolsi, Republic of Korea
BL

Byungho Lee

Professor
orthopedic spinal surgery, Gangnam Severance hospital, college of medicine, Yonsei university, Seoul-t'ukpyolsi, Republic of Korea
SP

Si-Young Park

Professor
Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea, Seoul-t'ukpyolsi, Republic of Korea
JH

Joong-Won Ha

Professor
Department of Orthopedic Surgery, National Health Insurance Service Ilsan Hospital, Goyang, Republic of Korea, Kyonggi-do, Republic of Korea
KS

Kyung-Soo Suk

Professor
Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul-t'ukpyolsi, Republic of Korea
SM

Seong-Hwan Moon

Professor
Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea, Seoul-t'ukpyolsi, Republic of Korea
HK

Hak-Sun Kim

Professor
Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea, Seoul-t'ukpyolsi, Republic of Korea

Submitter(s)

JI WON KWON, n/a

Assistant professor
Yonsei university college of medicine
강서구, Seoul-t'ukpyolsi, Republic of Korea

Introduction: Cortical bone trajectory(CBT) screw is an alternative and less-invasive technique for lumbar pedicle screw placement. however, the incidence and risk factor of adjacent segment disease(ASD) following transforaminal lumbar interbody fusion(TLIF) using the CBT screw (CBT-TLIF) remains unknown.
Aim/

Objectives: The purpose of this study was to determine whether the proximity of the endplate on the upper instrumented vertebra(UIV) using CBT screw can be a predictive factor for radiologic adjacent segment disease(r-ASD).

Methods: Among patients surgically treated with CBT-TLIF in a single institute, 276 consecutive patients (91 males, 185 females) with degenerative lumbar spondylolisthesis (DLS) who were followed up for at least 24 months were exclusively enrolled. Their clinical and radiological features, including the incidence of r-ASD and significantly associated factors for the developing r-ASD, were retrospectively measured. R-ASD was defined by the following adjacent segment criteria: > 3 mm anteroposterior translation, > 10° segmental kyphosis, or > 50% loss of disc height. In addition, the proximity between the UIV and the proximal screw was defined when the distance between the endplate of the UIV and the tip of the proximal screw was within 3 mm using computed tomography.

Results: R-ASD was observed in 94 (36.1%) cases at 2 years postoperative follow-up. Preoperative Weishaup classification on adjacent segment (> grade 2), long fusion (> 2 levels), and proximity of endplate on UIV were significantly associated with r-ASD in univariate logistic regression. (OR = 3.93, 95% CI [(1.31-11.75] versus OR = 2.67, 95% CI [1.56–4.58] versus OR = 2.00, 95% CI [1.15–3.47]). Among them, proximity of endplate on UIV was significantly found as a risk factor for r-ASD even in multivariate logistic regression. (OR = 2.76, 95% CI [(1.48-5.13])

Conclusions: Proximity of endplate on UIV using cortical bone trajectory screws can be a risk factor for early onset postoperative radiologic adjacent segment disease