Erratum to Surgical Risk Stratification Based on Preoperative Risk Factors in Severe Pediatric Spinal Deformity Surgery [Spine Deformity 2 (2014) 340-349].

The corresponding author regret that co-author name was incorrectly published as "Elias C. Papadopoulus" in the article. The correct name of the author should be displayed as "Elias C. Papadopoulos".

Delayed Postoperative Neurologic Deficits in Spinal Deformity Surgery.

STUDY DESIGN: A cross-sectional survey of surgeon members of the Scoliosis Research Society (SRS). OBJECTIVE: This study sought to characterize the incidence, clinical presentation, diagnostic workup, treatment, and neurologic prognosis following delayed postoperative neurologic deficit (DPND) in patients undergoing spinal deformity surgery. SUMMARY OF BACKGROUND DATA: DPND is a potentially devastating condition following spinal surgery, characterized by the development of a neurological deficit within hours or days of the surgical procedure. To date, only case reports and small case series have been published on the topic. METHODS: We developed a survey to characterize DPND following spinal deformity surgery. This survey was distributed to surgeon members of the SRS through email and standard mail. The overall response rate was 38% (352/929). RESULTS: Our results suggest an estimated DPND incidence of 1 of 9910 cases (0.01%). Eighty-one surgeons (23%) experienced at least 1 DPND in the past 10 years (92 total cases). Most common diagnoses were scoliosis (69%), kyphosis (23%), and spondylolisthesis (14%); 20% were revision surgeries. The number of hours to deficit onset was as follows: 1 to 12 (36%), 13 to 24 (27%), 25 to 48 (27%), more than 48 (10%). The most commonly cited sources of injury included ischemic injury (38%) and cord compression (15%). Forty-one percent experienced complete neurologic recovery, 26% partial, and 33% no recovery. Twenty-one percent of patients achieved final neurologic status within 1 week, 38% by 1 month, and 73% by 6 months. Patients with compression-related DPND had a significantly greater likelihood of experiencing some neurologic recovery (≥1 ASIA Grade) than ischemia-related DPND (86% versus 51%, P = 0.049). CONCLUSIONS: DPND occurs at an estimated incidence of 0.01%. Sixty-three percent of DPND cases occurred within the first 24 hours and 90% within 48 hours. Complete (41%) or partial (26%) neurologic recovery may be expected, especially in compression-related DPND, emphasizing the need for perioperative vigilance, prompt recognition, and early intervention. LEVEL OF EVIDENCE: 4.

Results of the 2014 SRS Survey on PJK/PJF: A Report on Variation of Select SRS Member Practice Patterns, Treatment Indications, and Opinions on Classification Development.

STUDY DESIGN: An electronic survey administered to Scoliosis Research Society membership. OBJECTIVE: To characterize surgeon views regarding proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) management providing the framework in which a PJK/PJF classification system and treatment guidelines could be established. SUMMARY OF BACKGROUND DATA: PJK/PJF are common complications of adult spinal deformity surgery. To date, there is no consensus on PJK/PJF definitions, classification, and indications for revision surgery. There is a paucity of data on deformity surgeon practice pattern variations and consensus opinion on treatment and prevention. METHODS: An electronic 19-question survey regarding PJK/PJF was administered to members of the Scoliosis Research Society who treat adult spinal deformity. Determinants included the surgeons' type of practice, number of years in practice, agreement with given PJK/PJF definitions, importance of key factors influencing prevention and revision, prevention methods currently used, and the importance of developing a classification system. RESULTS: A total of 226 surgeons responded (38.8% response rate). Both 44.4% of surgeons selected "extremely important" and 40.8% selected "very important" that PJK in adult spinal deformity surgery is a very important issue and that a Scoliosis Research Society PJK/PJF classification system and guidelines for detection and prevention of PJK/PJF is a "must have" (18.1%) and "very likely helpful" (31.9%). Both 86.2% and 90.7% of surgeons agreed with the provided definitions of PJK and PJF, respectively. Top 5 revision indications included neurological deficit, severe focal pain, translation or subluxation fracture, a change in kyphosis angle of greater than 30°, chance fracture, spondylolisthesis greater than 6 mm, and instrumentation prominence. The majority of respondents use a PJK/PJF prevention strategy 60% of the time or more, the most common were terminal rod contour, preoperative bone mineral density testing, and frequent radiographical studies during first 3 months postoperative, preoperative bone mineral density medication for low bone mineral density. CONCLUSION: The results of this study provide insight from the practicing surgeons' perspective of the management of PJK and PJF that may aid in the validation of current definitions and consensus-based treatment decisions and prevention guidelines. LEVEL OF EVIDENCE: 5.

Proximal junctional kyphosis and failure after spinal deformity surgery: a systematic review of the literature as a background to classification development.

STUDY DESIGN: Systematic review of literature. OBJECTIVE: To perform a comprehensive English language systematic literature review of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF), concentrating on incidence, risk factors, health related quality of life impact, prevention strategy, and classification systems. SUMMARY OF BACKGROUND DATA: PJK and PJF are well described clinical pathologies and are a frequent cause of revision surgery. The development of a PJK classification that correlates with clinical outcomes and guides treatment decisions and possible prevention strategies would be of significant benefit to patients and surgeons. METHODS: The phrases "proximal junctional," "proximal junctional kyphosis," and "proximal junctional failure" were used as search terms in PubMed for all years up to 2014 to identify all articles that included at least one of these terms. RESULTS: Fifty-three articles were identified overall. Eighteen articles assessed for risk factors. Eight studies specifically reviewed prevention strategies. There were no randomized prospective studies. There were 3 published studies that have attempted to classify PJK. The reported incidence of PJK ranged widely, from 5% to 46% in patients undergoing spinal instrumentation and fusion for adult spinal deformity. It is reported that 66% of PJK occurs within 3 months and 80% within 18 months after surgery. The reported revision rates due to PJK range from 13% to 55%. Modifiable and nonmodifiable risk factors for PJK have been characterized. CONCLUSION: PJK and PJF affect many patients after long segment instrumentation after the correction of adult spinal deformity. The epidemiology and risk factors for the disease are well defined. A PJK and PJF scoring system may help describe the severity of disease and guide the need for revision surgery. The development and prospective validation of a PJK classification system is important considering the prevalence of the problem and its clinical and economic impact. LEVEL OF EVIDENCE: N/A.

Surgical Risk Stratification Based on Preoperative Risk Factors in Severe Pediatric Spinal Deformity Surgery.

STUDY DESIGN: Retrospective review. OBJECTIVE: The purpose of this study is to review the postoperative complications in pediatric patients undergoing spine surgery and to establish a preoperative classification that stratifies surgical risk and case difficulty. SUMMARY OF BACKGROUND DATA: Pediatric spinal deformity (PSD) surgery can be challenging technically as well as economically. Often, a multidisciplinary approach to managing these patients is necessary. In an environment where resources are limited, such as in global outreach efforts, a method for stratifying PSD surgical cases can be useful for allocating appropriate resources and assigning appropriate skill sets in order to optimize patient outcomes and to streamline efforts. MATERIALS AND METHODS: A total of 145 consecutive PSD patients who underwent instrumented spinal fusion were reviewed. Radiographic measurements and demographic data were reviewed. A classification was established based on the curve magnitude, etiology, ASA grade, number of levels fused, the preoperative neurologic status, body mass index and type of osteotomies. Multiple regression analysis (MRA) and logistic regression analysis (LRA) were applied to indicate risk factors for complications. RESULTS: The average age was 14.3 years (10-20 years). The etiology was idiopathic scoliosis (n = 71), congenital scoliosis (n = 38), infectious (n = 11), and others. 23 patients had neurologic deficits preoperatively. Twenty-three patients had a posterior vertebral column resection. Patients were classified as Level 1 (n = 5), Level 2 (n = 19), Level 3 (n = 24), Level 4 (n = 58), and Level 5 (n = 39). Intraoperative neuro-monitoring changes were observed in 46 cases. Major complications were seen in 45 cases. A major complication consisted of implant related (n = 13), deep wound infection (n = 8), neurologic deficit (n = 7), death (n = 2), and others (n = 9). MRA demonstrated a significant correlation between classified level and %EBL/TBV, operative time, and complication rate. The risk level predicted the occurrence of general (odds ratio [OR] = 1.54; 95% confidence interval [CI] = 1.08-2.21; p = .019) and neurologic (OR = 3.34; 95% CI = 1.06-17.70; p = .036) complications. Osteotomy and resection procedures were independent predictors for postoperative neurologic complications (OR = 1.7, 95% CI = 1.11-2.85; p = .015). CONCLUSION: Corrective spine surgery for complex pediatric deformity is challenging and carries a substantial risk. No single parameter appears to independently predict postoperative complications. However, when all risk factors are considered, there is a trend toward increased intraoperative electromonitoring change and postoperative neurologic risk with the higher level score in our classification. The newly established surgical risk stratification based on patient-specific clinical and radiographic factors can guide surgeons in their preoperative planning and surgical management of severe spine deformity in order to achieve optimal outcomes.