Study Design.: Retrospective study. Objective.: The aim of this study was to investigate the risk factors for proximal junctional failure (PJF) following long instrumented fusion stopping at thoracolumbar junction (TLJ) in adult spinal deformity (ASD) and to determine which cases are suitable for TLJ stop without increasing the risk for PJF. Summary of Background Data.: PJF following long fusion for ASD is a well-recognized complication that negatively affects clinical outcomes. Generally, the uppermost instrumented vertebra (UIV) at the TLJ is associated with the risk of PJF. Little is known about the risk factors for PJF in case with the UIV at TLJ. Methods.: Radiographic and clinical data of 63 consecutive patients who underwent instrumented fusion from sacrum to TLJ (T11, T12, and L1) for the treatment of ASD with a minimum 2-year follow-up were analyzed to identify the risk factors for PJF, which was defined as proximal junctional angle (PJA) ≥20°, fracture at UIV or UIV+1, failure of UIV fixation, myelopathy, or ‘need for proximal extension of fusion. Results.: During the average follow-up duration of 51.7 months, PJF developed in 23 patients (36.5%) at a mean of 9.3 months after surgery. Multivariate analysis revealed that age >70 years (odds ratio [OR]: 1.119), osteoporosis (OR: 4.459), and preoperative kyphotic PJA (OR: 1.138) were significant risk factors for the development of PJF. No PJF occurred in 14 patients lacking any risk factors. The last follow-up clinical results were significantly inferior in the PJF group than in the non-PJF group in terms of Oswestry Disability Index and Scoliosis Research Society-22 score. Conclusion.: Age >70 years, osteoporosis, and PJA greater 0° were identified as significant risk factors for PJF. Therefore, the TLJ level can be considered as UIV selectively for patients younger than 70 years without osteoporosis and with lordotic preoperative PJA. Level of Evidence: 3

Study Design.: Retrospective study. Objective.: To validate the age-adjusted ideal sagittal alignment in terms of proximal junctional failure (PJF) and clinical outcomes. Summary of Background.: It is reported that optimal sagittal correction with regard to the age-adjusted ideal sagittal alignment reduces the risk of PJF development. However, few studies have validated this concept. The age-considered optimal correction is likely to be undercorrection in terms of conventional surgical target, such as pelvic incidence (PI)−lumbar lordosis (LL) within ±9°. Therefore, the clinical impact of age-adjusted sagittal alignment should be evaluated along with radiographic effect. Materials and Methods.: Adult spinal deformity patients, aged 50 years and above, who underwent greater than or equal to four-level fusion to sacrum with a minimum of four years of follow-up data were included in this study. Radiographic risk factors for PJF (including age-adjusted ideal PI−LL) were evaluated with multivariate analyses. Three groups were created based on PI−LL offset between age-adjusted ideal PI−LL and actual actual PI−LL: undercorrection, ideal correction, and overcorrection. Clinical outcomes were compared among the three groups. Results.: This study included 194 adult spinal deformity patients. The mean age was 68.5 years and there were 172 females (88.7%). PJF developed in 99 patients (51.0%) at a mean postoperative period of 14.9 months. Multivariate analysis for PJF revealed that only PI−LL offset group had statistical significance. The proportion of patients with PJF was greatest in the overcorrection group followed by the ideal correction and undercorrection groups. Overcorrected patients regard to the age-adjusted ideal alignment showed poorer clinical outcomes than the other patient groups. Conclusions.: Overcorrection relative to age-adjusted sagittal alignment increases the risk of PJF development and is associated with poor clinical outcomes. Older patients and those with small PI are likely to be overcorrected in terms of the age-adjusted PI−LL target. Therefore, the age-adjusted alignment should be considered more strictly in these patients.

Osteoporotic vertebral compression fractures (OVCF) can cause severe pain, changes in balance, gait velocity, muscle fatigue, risk of falls, and subsequent fractures. Thus, OVCF significantly lowers the individual’s health-related quality of life. Additionally, OVCF may increase patient mortality rates. However, studies on post-OVCF mortality are limited. This study aimed to evaluate mortality risk after the first occurrence of OVCF in the general population using a nationwide dataset from the Korean National Health Insurance System. We identified 291,203 newly diagnosed patients with OVCF and 873,609 patients without OVCF at a ratio of 1:3 matched by sex and age between 2010 and 2012. We investigated the latent characteristics of patients’ demographic information and chronic comorbidities that could affect mortality when diagnosed with OVCF. By comparing the cohort data, the hazard ratio for subsequent mortality in patients with OVCF was calculated and adjusted based on several risk factors. Despite adjusting for demographic characteristics and chronic comorbidities, the risk of mortality was 1.22 times higher in the OVCF cohort than in the control group. Multivariate analysis showed that male sex, old age, low-income status, and high Charlson Comorbidity Index were associated with a higher risk of mortality. In addition, the presence of chronic comorbidities, including diabetes mellitus, ischemic heart disease, stroke, chronic obstructive pulmonary disease, cancer, and end-stage renal disease, was shown to increase the risk of mortality. This population-based cohort study showed that newly diagnosed OVCF significantly increased the subsequent risk of mortality. Moreover, post-OVCF mortality is influenced by demographic characteristics and chronic comorbidities.

BACKGROUND: Four guidelines have been suggested for optimal correction in adult spinal deformity surgery: Scoliosis Research Society (SRS)-Schwab classification, age-adjusted sagittal alignment goals, Global Alignment and Proportion (GAP) score, and the Roussouly algorithm. Whether these goals provide benefit in both proximal junctional kyphosis (PJK) reduction and clinical outcome improvement remains unclear. OBJECTIVE: To validate 4 preoperative surgical planning tools in PJK development and clinical outcomes. METHODS: We retrospectively reviewed patients who underwent ≥5-segment fusion including the sacrum for adult spinal deformity with a follow-up of ≥2-year. PJK development and clinical outcomes were compared among the groups separately using 4 surgical guidelines: SRS-Schwab pelvic incidence (PI)-lumbar lordosis (LL) modifier (Group 0, +, ++), age-adjusted PI-LL goal (undercorrection, matched correction, and overcorrection), GAP score (proportioned, moderately disproportioned, and severely disproportioned groups), and the Roussouly algorithm (restored and nonrestored groups). RESULTS: A total of 189 patients were included in this study. The mean age was 68.3 years, and there were 162 women (85.7%). There were no differences in the rate of PJK development and clinical outcomes among SRS-Schwab PI-LL modifier and GAP score groups. With the age-adjusted PI-LL goal, PJK developed significantly less frequently in the matched group compared with the under- and overcorrection groups. Clinical outcomes were significantly better in the matched group compared with the under- and overcorrection groups. With the Roussouly algorithm, PJK developed significantly less frequently in the restored group than in the nonrestored group. However, there were no differences in clinical outcomes between the 2 Roussouly groups. CONCLUSION: Correction according to the age-adjusted PI-LL goal and the restored Roussouly type was associated with reduced PJK development. However, differences in clinical outcomes were only observed in the age-adjusted PI-LL groups.

The aim of this study is to determine the prevalence and incidence of ankylosing spondylitis (AS) in South Korea, 2010–2015. This study was conducted using the Health Insurance Review Agency (HIRA) database, which includes information on every patient diagnosed with AS. The incidence and prevalence of AS were evaluated by age, sex, and income status. The prevalence increased linearly by 7.7% annually, i.e., 31.62 in 2010 to 52.30 in 2015 (per 100,000 persons). During the study period, the incidence was 6.34 per 100,000 person-years. The prevalence peaked for both men and women in the age range 30–39 years. Incidence peaked for men in the age range 20–29 years, but peaked for women between ages 70 and 89. AS was 3.6 times more prevalent in men than in women, and the incidence in men was 2.1 times greater than in women. With respect to income status, the prevalence and incidence of AS were 3 times greater and 5 times greater, respectively, in medical aid recipients compared to individuals with other income levels. The trend of increasing AS prevalence and the observation that 14.3% of all patients newly diagnosed with AS are medical aid recipients have significant implications for healthcare planning.