{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T01:28:58Z","timestamp":1782350938460,"version":"3.54.5"},"reference-count":23,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"6","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2020,12]]},"abstract":"<jats:sec><jats:title>OBJECTIVE<\/jats:title><jats:p>Scheuermann kyphosis (SK) could require surgical treatment in certain situations. A posterior reduction is the most widespread treatment so far, although the development of proximal junctional kyphosis (PJK) is one of the possible complications of this procedure. The contour of the proximal part of the rod could influence the occurrence of PJK in SK patients. The objective of this study was to analyze the impact of the proximal rod contour on the occurrence of a PJK complication in SK patients.<\/jats:p><\/jats:sec><jats:sec><jats:title>METHODS<\/jats:title><jats:p>This retrospective monocentric study was performed in the Nanjing Spine Surgery Department. All eligible patients had undergone posterior correction surgery with pedicle screws only between 2002 and 2017 and had at least 24 months of follow-up. The presence of PJK was quantified on radiographs using the proximal junctional angle (PJA &gt; 10\u00b0 at the last follow-up). The authors propose a new radiological parameter to measure the angulation of the proximal part of the instrumentation: the proximal contouring rod angle (PCRA) is the angle between the upper endplate of the upper instrumented vertebra (UIV) and the lower endplate of the second vertebra caudal to the UIV. The patients were analyzed according to the presence or absence of PJK. A t-test, receiver operating characteristic (ROC) curve analysis, and logistic regression analysis were performed for statistical analysis.<\/jats:p><\/jats:sec><jats:sec><jats:title>RESULTS<\/jats:title><jats:p>Sixty-two patients treated for SK were included in this study. The mean age was 18.6 \u00b1 8.5 years, and the mean follow-up was 42.5 \u00b1 16.4 months. The mean correction rate of global kyphosis was 46.4% \u00b1 13.7%. At the last follow-up, 17 patients (27.4%) presented with PJK. No significant difference was found between the PJK and non-PJK groups in terms of age and other preoperative variables. A significant difference in the postoperative PCRA was found between the PJK and non-PJK groups (8.2\u00b0 \u00b1 4.9\u00b0 vs 15.7\u00b0 \u00b1 6.6\u00b0, respectively; p = 0.001). A postoperative PCRA less than 10.1\u00b0 predicted a significantly higher risk for PJK (p = 0.002, OR 2.431, 95% CI 1.781\u20134.133).<\/jats:p><\/jats:sec><jats:sec><jats:title>CONCLUSIONS<\/jats:title><jats:p>Under-contouring of the proximal part of the rods (lower than 10\u00b0) is a risk factor for PJK after posterior correction of SK.<\/jats:p><\/jats:sec>","DOI":"10.3171\/2020.5.spine20229","type":"journal-article","created":{"date-parts":[[2020,8,7]],"date-time":"2020-08-07T07:17:21Z","timestamp":1596784641000},"page":"830-837","source":"Crossref","is-referenced-by-count":4,"title":["Under-contouring of rods: a potential risk factor for proximal junctional kyphosis after posterior correction of Scheuermann kyphosis"],"prefix":"10.3171","volume":"33","author":[{"given":"Michael","family":"Grelat","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Dijon University Hospital, Dijon, France; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chang-Zhi","family":"Du","sequence":"additional","affiliation":[{"name":"Department of Spine Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liang","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Spine Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xu","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Spine Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong","family":"Qiu","sequence":"additional","affiliation":[{"name":"Department of Spine Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"issue":"19","key":"b1","series-title":"Spine (Phila Pa 1976)","doi-asserted-by":"publisher","first-page":"1690","DOI":"10.1097\/BRS.0b013e31829ee8b7","article-title":"Scheuermann disease: evaluation of radiological criteria and population prevalence","volume":"38","author":"Makurthou AA","year":"2013","unstructured":"Makurthou AA, Oei L, El Saddy S,  Scheuermann disease: evaluation of radiological criteria and population prevalence. 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