Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S101−S140 259. Under-contoured proximal rod: a potential risk factor of PJK in Scheuermann’s kyphosis Michael Grelat, MD1, Changzhi Du, MD2, Xu Sun, MD3, Yong Qiu, MD2; 1 University Hospital of Dijon, DIJON, France; 2 The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China; 3 Nanjing Drum Tower Hospital, Nanjing, China BACKGROUND CONTEXT: Correction of kyphosis in Scheuermann’s Kyphosis (SK) patients can be effectively achieved via a multilevel Ponte osteotomies pedicle screw-based instrumentation. However, the risk of developing proximal junctional kyphosis remains an important issue after surgeries for SK. The influence of the proximal rod contouring on the occurrence of PJK has not been investigated in SK patients. PURPOSE: The aim of this study was to evaluate the influence of the proximal rod contouring on the radiographic results in patients with Scheuermann’s Kyphosis. STUDY DESIGN/SETTING: Single-center retrospective study. PATIENT SAMPLE: This study included 59 patients with SK (57 men, 2 women), who had undergone posterior correction surgery between 2002 and 2015, and had been followed at least 12 months. OUTCOME MEASURES: 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 UIV (UIV2). A PJK was defined by the presence of a proximal junctional angle (PJA) greater than 10˚ at the latest follow-up, and the increase of this angle by more than 10˚ compared with preoperatively. METHODS: Patients were separated into 2 groups: PJK group and nonPJK group. Comparisons were performed in terms of T-test between these two groups. ROC curve analysis and logistic regression analysis were performed. RESULTS: The mean age was 20.24 § 9.47 years old and the follow-up average were 16.3 months § 8.3. No significant difference was found between two groups with regards to their ages, the PJA and the PCRA at preoperative time. At the last follow-up, 31,7% of the patients developed PJK, the mean value of PJA was 19.21 § 4.6 in PJK group and was 7.76 § 3.72 in non-PJK group (p<0.0001), respectively. Significant difference was found in the postoperative PCRA between the PJK group and the nonPJK group (9.52 § 5.34˚ and 14.33 § 6.6˚, respectively; p=0.008). As revealed by regression analysis and demonstrated by ROC curve, a PRCA less than 10.05˚ predicted significant high risk of PJK (Se=80%, Sp=73.7%; p=0.023, OR=1.143, CI=1.019-1.283). CONCLUSIONS: Patients whose PCRA angle are lower than 10˚ after surgery are more likely to develop PJK, demonstrating that under-contouring of the proximal rod is a risk factor for PJK in SK. So, proximal portion of the rod should be bent more kyphotic (more than 10˚ ). FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.274
260. How much lordosis can be restored by minimally invasive multilevel lateral lumbar interbody fusion combined with posterior column osteotomy using stiff rod (6.35 mm cobalt chrome) in adult spinal deformity surgery? Jung-Hee Lee, MD, PhD1, Ki Young Lee, MD2, Won Ju Shin, MD1, Sang Kyu Im, MD3, Seong Jin Cho, MD4, Jin Soo Kim5; 1 Kyung Hee University Medical Center, Seoul, Republic of Korea; 2 Department of Orthopedic Surgery, Graduate School, College of Medicine, Kyung Hee University, Republic of Seoul, Korea; 3 Seoul, Republic of Korea; 4 KyungHee Medical Center, Seoul, Republic of Korea; 5 Barosun Hospital, Seoul, Republic of Korea BACKGROUND CONTEXT: Pedicle subtration osteotomy (PSO) is highly effective as a method for sagittal correction in patients with adult spinal deformity, but there are issues such as surgical complexity and longterm complications. Although, recently, minimally invasive techniques
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have been reported to be useful for surgical treatment of adult spinal deformity, few reports have directly compared it with PSO. PURPOSE: The purpose of this study was to evaluate the radiological and clinical efficacies of lateral lumbar interbody fusion (LLIF) combined with posterior column osteotomy (PCO) using stiff rod (6.35 mm Cobalt Chrome; CoCr). STUDY DESIGN/SETTING: Retrospective, consecutive case review. PATIENT SAMPLE: A total of 106 patients (average age 71.5 years) who were diagnosed adult spinal deformity with sagittal imbalance and followed up for more than 2 years after sagittal correction OUTCOME MEASURES: Description and analysis of X-ray and clinical questionaires (Oswestry Disability Index, Visual Analogie Scale) METHODS: Comparative analysis was performed on the spinopelvic parameters and clinical outcomes of patients who underwent PSO (PSO group; n=65) and the patients who underwent multilevel pre-psoas LLIF combined with PCO and open posterior spinal fusion using 6.35 mm Cobalt Chrome rod (LLIF group; n=41). RESULTS: There were no differences in preoperative spinopelvic parameters between PSO group and LLIF group. Although there were no differences between the two groups in terms of postoperative SVA (-12.7 mm vs -16.5 mm), postoperative lumbar lordosis (-71.5˚ vs -72.6˚), lumbar lordosis correction (78.0˚vs 73.5˚), sacral slope (46.3˚ vs 49.1˚) and pelvic tilt (9.4˚ vs 7.2˚), estimated blood loss was significantly lower in the LLIF group (2,824 ml vs 1,736 ml, P=0.000). No differences were observed in the clinical outcomes (Oswestry Disability Index, Visual Analog Scale), proximal junctional kyphosis, and spinopelvic parameters between the two groups 2 years after the surgery, but reoperation due to pseudarthrosis was significantly higher in the PSO group (P=0.004). CONCLUSIONS: Minimally invasive multilevel LLIF combined with PCO using a stiff rod leads to better clinical and radiological outcomes as much as PSO, accompanied by fewer long-term major complications, such as pseudarthrosis and reoperation. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.275
261. Appropriateness of decompression without fusion in patients with degenerative scoliosis: findings from the RAND/UCLA appropriate use criteria study Michael D. Daubs, MD1, Sukanta Maitra, MD2, Teryl Nuckols, MD, MS3; 1 Las Vegas, NV, US; 2 Optum, Las Vegas, NV, US; 3 Cedars-Sinai Medical Center, Los Angeles, CA, US BACKGROUND CONTEXT: The RAND/UCLA Appropriateness Method has been applied to at least 16 different surgical procedures, and several studies have documented that adherence to the resulting appropriateness criteria was associated with improved clinical outcomes. The appropriateness of various surgical procedures for the treatment of degenerative lumbar scoliosis (DLS) has not been universally agreed upon. The appropriateness of decompression without fusion in the setting of degenerative scoliosis remains controversial. PURPOSE: The purpose of this study was to evaluate the indications and appropriateness of decompression without fusion in patients with degenerative scoliosis and stenosis. STUDY DESIGN/SETTING: Rand/UCLA Appropriate Use Criteria (AUC) Method. METHODS: We used the RAND/UCLA Appropriateness Method, which includes a systematic review of the literature and a multidisciplinary modified-Delphi panel process. The panel included 3 neurosurgeons, 3 orthopedic spine surgeons, 2 physiatrists, a researcher/physical therapist and a geriatrician. We developed 260 scenarios based on 7 different clinical characteristics, including sagittal imbalance. Panelists discussed the balance of risks and benefits and then rated the appropriateness of five surgical procedures (decompression alone, fusion alone, decompression and fusion,
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