en ستون فقرات Spine surgery پژوهشی Research Article <p dir="auto"><span style="font-size:14px;"><span style="font-family:Arial;"><span style="line-height:107%"><b>Background and Objective:</b> Proximal junctional kyphosis (PJK) is a common complication of long spinal fusion. The relationship between body mass index (BMI) and PJK is controversial. This study aimed<b> </b>to evaluate the relationship between patient BMI and PJK prevalence in patients undergoing long spinal fusion. </span><br> <span style="line-height:107%"><b>Methods:</b> This retrospective study included 76 patients who underwent long spinal fusion (&ge;5 levels or pelvic fixation) for degenerative canal stenosis with a minimum 24-month follow-up. PJK was defined as &ge;10&deg; increase in Cobb angle between the UIV inferior endplate and the UIV+2 superior endplate. </span><br> <span style="line-height:107%"><b>Results:</b> PJK occurred in 26 patients (34.2%) at early follow-up (&le;6 months) and in 18 patients (23.7%) at late follow-up (>6 months). Mean BMI was significantly higher in the early PJK group (29.6 vs. 23.4 kg/m&sup2;, <i>P</i> < 0.001). BMI was an independent predictor of early PJK (OR = 1.32, 95% CI: 1.18-1.48, <i>P </i>< 0.001). Overweight patients (BMI>25) had a 69.6% early PJK rate vs. 20.5% in normal-weight patients. Surgically treated early PJK patients had higher mean BMI (30.8 vs. 28.4 kg/m&sup2;, <i>P</i> = 0.023). </span><br> <span style="line-height:107%"><b>Conclusion:</b> Higher BMI is significantly associated with early PJK following long spinal fusion, particularly in the first 6 months postoperatively. </span></span></span><br> &nbsp;</p> Proximal junctional kyphosis (PJK), Body mass index (BMI), Long spinal fusion, Degenerative canal stenosis 0 0 http://jros.iums.ac.ir/browse.php?a_code=A-10-2742-1&slc_lang=en&sid=1 Ebrahim Ameri AMERI.EB@GMAIL.COM 10031947532846008904 10031947532846008904 No Bone and Joint Reconstruction Research Center, Iran University of Medical Sciences, Shafa Yahyaeian Hospital, Tehran, Iran Hassan Ghandhari HASSANghandhari@gmail.com 10031947532846008905 10031947532846008905 No Bone and Joint Reconstruction Research Center, Iran University of Medical Sciences, Shafa Yahyaeian Hospital, Tehran, Iran Farshad Nikoii NIKOIIF@GMAIL.COM 10031947532846008906 10031947532846008906 No Bone and Joint Reconstruction Research Center, Iran University of Medical Sciences, Shafa Yahyaeian Hospital, Tehran, Iran Mohammad Reza Shakeri MRCHEHRASAN@GMAIL.COM 10031947532846008907 10031947532846008907 No Bone and Joint Reconstruction Research Center, Iran University of Medical Sciences, Shafa Yahyaeian Hospital, Tehran, Iran Mohammad Reza Chehrasan SHAKERMR@GMAIL.COM 10031947532846008908 10031947532846008908 No Bone and Joint Reconstruction Research Center, Iran University of Medical Sciences, Shafa Yahyaeian Hospital, Tehran, Iran Javad Moeini JMOIINI@GMAIL.COM 10031947532846008909 10031947532846008909 No Bone and Joint Reconstruction Research Center, Iran University of Medical Sciences, Shafa Yahyaeian Hospital, Tehran, Iran Ehsan Ghavidel GHAVIDELE@GMAIL.COM 10031947532846008910 10031947532846008910 Yes Bone and Joint Reconstruction Research Center, Iran University of Medical Sciences, Shafa Yahyaeian Hospital, Tehran, Iran