The use of lateral lumbar interbody fusion for identifying adult patients with spinal deformities treatable by short corrective fusion in 2-stage surgery.

BACKGROUND: To investigate and compare the surgical outcomes of short and thoracopelvic corrective fusion with our two-stage technique using lateral lumbar interbody fusion (LLIF) and posterior open surgery. METHODS: Consecutive patients with adult spinal deformities who underwent a planned two-stage anterior-posterior surgery, using LLIF for the first stage and posterior open corrective fusion for the second stage, with a minimum of 2 years of follow-up were included. Patients who underwent lumbar or lumbosacral corrective fusion and thoracopelvic corrective fusion were categorized into the short group and thoracopelvic groups, respectively. We investigated the spinopelvic parameters and patient-reported outcome measurements. RESULTS: Seventy-four consecutive patients (8 men, 66 women; average age, 70.0 years) were included. Ten patients underwent short corrective fusion following significant improvements in the symptoms and radiographic parameters post-LLIF. Several preoperative spinopelvic parameters were better in the short group. Compared to the thoracopelvic group, those who underwent short fusion had a poorer alignment 2 years postoperatively but with comparable results and a significantly higher function score on the Scoliosis Research Society-22 r (SRS-22r) questionnaire. The mean Oswestry Disability Index and SRS-22r scores significantly improved during the 2-year postoperative follow-up in both the groups. CONCLUSIONS: Short corrective fusion can be considered in patients whose symptoms and radiographic parameters significantly improve following LLIF. Patients who undergo short fusion with LLIF application have poorer alignment than those who undergo thoracopelvic fusion 2 years postoperatively; however, the results are comparable, and the function score is significantly improved.

Perioperative lumbar subarachnoid drainage could not prevent postoperative CSF leakage after spinal cord tumor resection using an artificial dura mater.

BACKGROUND: Cerebrospinal fluid (CSF) leakage occurs in patients who undergo dural repair using artificial dura mater. This study aimed to determine if perioperative lumbar subarachnoid drainage could reduce the incidence of postoperative CSF leakage in cases of dural repair using artificial dura mater. METHODS: We retrospectively analyzed 84 patients (41 men, 43 women; mean age, 52.2 ± 20.1 years) who underwent intradural spinal cord tumor resection and dural repair using artificial dura mater. These patients were divided according to whether they underwent perioperative lumbar subarachnoid drainage (39 patients: D group) or had no drainage (45 patients: ND group). The incidence of radiographic and symptomatic CSF leakage as well as baseline characteristics and operative data were compared between the two groups. RESULTS: Radiographic CSF leakage was observed in 21 patients (25.0%), including 10 (25.6%) in the D group and 11 (24.4%) in the ND group. Symptomatic CSF leakage was observed in 12 patients (14.2%), including six (15,4%) in the D group and 11 (13.3%) in the ND group. There were no significant differences in the incidence of subcutaneous CSF accumulation and symptomatic CSF leakage between the two groups. In cases with symptomatic CSF leakage, the onset time of CSF leakage tended to be earlier (5.7 days vs 15.7 days), and the treatment period tended to be longer (5.8 weeks vs 2.8 weeks) in the ND group than in the D group. CONCLUSIONS: Perioperative lumbar subarachnoid drainage did not reduce the incidence of either radiographic or symptomatic CSF leakage. However, it might shorten the treatment period and reduce refractory CSF leakage, which requires multiple treatments over a long period.

Sex differences between the relationship of trunk muscle mass and whole body sagittal plane alignment in older adults.

BACKGROUND: This study aimed to clarify sex differences in the relationship between trunk muscle mass, aging, and whole-body sagittal alignment. METHODS: Subjects aged 60-89 years who underwent musculoskeletal screening in 2018 were included in the study. Subject demographics, trunk muscle mass (TMM) measured by bioelectrical impedance analysis (BIA), and spinopelvic and lower extremity alignment parameters measured from standing radiographic images were investigated. Additionally, TMM was corrected for BMI (TMM/BMI). The relationship between trunk muscle and whole-body sagittal alignment was analyzed for each age group (young-old group (60-74 years) and old-old group (>75 years)) and sex. RESULTS: A total of 281 (mean age 75.4 ± 6.7 years, 100 males and 181 females) were enrolled. The trunk muscle mass in both men and women significantly decreased with age. Regarding TMM/BMI, there was no significant difference in men, but there was a significant difference between females in the young-old and old-old groups (p < 0.001). TMM/BMI was significantly correlated with sagittal vertical axis (SVA) and knee flexion angle (KF) in both sexes. In females, TMM/BMI was significantly correlated with thoracic kyphosis in the young-old group, whereas in the old-old group, TMM/BMI was correlated with SVA, PI-LL, and KF. CONCLUSIONS: TMM was related to trunk anteverion and lower extremity alignment in both sexes. However, the relationship between TMM on alignment differs between sexes. Thoracic hyperkyphosis in young-old adults indicated a decrease in muscle mass, which may be a sign of future malalignment.

Characteristics of pedicle screw misplacement using freehand technique in degenerative scoliosis surgery.

PURPOSE: This study aimed to estimate the accuracy of pedicle screw (PS) placement in degenerative scoliosis surgery, characterize a patient population with PS misplacement, and analyze the association between misplaced PS vector and lumbar coronal curve. METHODS: In this study, 122 patients (average age 68.6 years), who underwent corrective and decompression surgery, were selected retrospectively. PS accuracy was evaluated in the thoracic to lumbar spine. We identified characteristics of misplacement in each patient. Screw positions were categorized into grade A, entirely in the pedicle; grade B, < 2 mm breach; grade C, 2-4 mm breach; and grade D, > 4 mm breach using postoperative computed tomography. RESULTS: The mean preoperative lumbar coronal curve was 32.3 ± 18.4°, and the number of fused vertebrae was 8.9 ± 2.8. A total of 2032 PS were categorized as follows: grade A, 1897 PS (93.3%); grade B, 67 (3.3%); grade C, 26 (1.3%); and grade D, 43 (2.1%). One PS (grade D), inserted at T5, needed surgery for removal due to neurological deficit. The misplacement group (grades C and D) had a significantly stronger lumbar coronal curve and apical vertebral rotation than the accuracy group (grades A and B). Misplaced PS vector (direction and degree) was significantly correlated with inserted vertebral rotation. Grade D misplacement was distributed mainly around the transitional vertebra of the lumbar curve. CONCLUSIONS: The accuracy of PS insertion in the thoracic to lumbar spine was high in DS surgery, but the need for care was highlighted in the transitional vertebra.

Effect of central sensitization inventory on the number of painful sites and pain severity in a Japanese regional population cohort.

BACKGROUND: To investigate the association between the central sensitization inventory (CSI), a screening tool for central sensitization, and the number of painful sites and the severity of pain in locomotive organs in an epidemiological study in the elderly. METHODS: A total of 379 individuals who underwent musculoskeletal disease screening were enrolled in this study. The CSI was used to assess symptoms of central sensitization. The number and location of painful sites and the severity of pain were evaluated using pain mapping and a numerical rating scale (NRS) at 37 sites. We investigated the association between the number of painful sites and CSI score, and the association between the severity of low back pain or knee pain and CSI score. RESULTS: There was a positive correlation between CSI score and the number of painful sites. The CSI score was significantly higher in those with significant low back pain than in those without pain, and the high-CSI group tended to have a greater number of painful sites. Comparison of CSI scores between participants with low back pain alone and those with low back pain and posterior lower leg pain showed that the latter group had a significantly higher CSI score than the former group. The CSI score in participants with radiographic evidence of knee osteoarthritis was significantly higher in those with knee pain than in those without pain. CONCLUSIONS: The results of this study suggest that participants with significant low back pain and a higher number of painful sites are more susceptible to the influence of central sensitization. In addition, CSI score was higher in participants with low back pain and posterior lower leg pain than in those with low back pain alone, suggesting that the spread of pain may be due to central sensitization.

Disc degeneration could be recovered after chemonucleolysis with condoliase.-1 year clinical outcome of condoliase therapy.

BACKGROUND: Condoliase-induced chemonucleolysis is a less-invasive alternative treatment for lumbar disc herniation (LDH); however, its long-term clinical outcome is still unclear. This study aimed to investigate 1-year clinical outcomes and assess radiographs after chemonucleolysis with condoliase. METHODS: We enrolled patients with LDH who received condoliase injection with a follow-up period of >1 year. Sixty patients (37 men, 23 women; mean age, 44.5 ± 18.9 years; mean follow-up period, 22.0 ± 6.0 months) were analyzed. Changes in disc height and degeneration were evaluated using magnetic resonance imaging. Visual analog scale (VAS) scores for leg and back pain and the Oswestry disability index (ODI) were obtained. All data were assessed at baseline, 1-month, 3-month, and 1-year follow-up. RESULTS: Surgical treatment was subsequently required in 8 patients (12.5%) after condoliase therapy. Their ODI and VAS scores for leg pain and back pain significantly improved at 1 year, as in those who received condoliase therapy only. On MRI, progression of Pfirrmann grade was observed in 23 patients (44.2%) at 3 months; however, 8 patients recovered to baseline at 1 year. The mean disc height decreased at 3 months; however, it recovered at 1 year. Disc height recovery (disc recovery rate >50%) was observed in 30.8% of the patients. Patients with disc height recovery were significantly younger than those without. Patients with longer symptom duration (≥1 year) showed significantly lower rates of effectiveness compared with those with shorter symptom durations (<1 year). CONCLUSIONS: Chemonucleolysis with condoliase is a safe and minimally invasive treatment. Disc degeneration induced by chemonucleolysis could be recovered, particularly in younger patients. Prolonged symptom duration had adverse effects on outcome; thus, therapeutic intervention at the optimal time is needed.

Planned two-stage surgery using lateral lumbar interbody fusion and posterior corrective fusion: a retrospective study of perioperative complications.

PURPOSE: To determine the effect of planned two-stage surgery using lateral lumbar interbody fusion (LLIF) on the perioperative complication rate following corrective fusion surgery in patients with kyphoscoliosis. METHODS: Consecutive patients with degenerative scoliosis who underwent corrective fusion were divided into a control group that underwent single-stage posterior-only surgery and a group that underwent planned two-staged surgery with LLIF and posterior corrective fusion. We collected the patient background and surgical data and assessed the perioperative complication rates. We also investigated spinopelvic parameters and patient-reported outcome measurements (PROMs). RESULTS: One hundred and thirty-eight patients of mean age 69.8 (range, 50-84) years who met the study inclusion criteria were included. The two-stage group (n = 75) underwent a staged anterior-posterior surgical procedure, and the control group (n = 63) underwent single-stage surgery. There was no significant between-group difference in the incidence of perioperative complications, except for deep wound infection (reoperation is necessary for surgical site infection). Revision surgery within 3 months of the initial surgery was more common in the control group (n = 8, 12.7%) than in the two-stage group (n = 3, 4.0%). Spinopelvic parameters and PROMs were significantly better in the two-stage group at 2 years postoperatively. CONCLUSION: The complication rate for planned two-stage surgery was similar to that of previous posterior-only single-stage surgery. However, early reoperation was less common, and the degree of spinal correction and clinical results were significantly better after two-stage surgery.

Does preoperative prognostic nutrition index predict surgical site infection after spine surgery?

PURPOSE: Malnutrition is reported as one of the risk factors for surgical site infection (SSI). The prognostic nutritional index (PNI) is a simple method for nutritional evaluation. However, little is known about the relationship between SSI and the PNI in patients after spine surgery. We aimed to determine independent predictors of SSI after spine surgery. METHODS: We analyzed 1115 patients who underwent spine surgery (369 males, 746 females, mean age 56 years, follow-up period: at least 1 year). Patients were divided into SSI and non-SSI groups. Preoperative risk factors, including PNI (10 × serum albumin [g/dL] + 0.005 × total lymphocyte count [/µL]), were assessed. RESULTS: Postoperatively, 43 patients (3.9%) experienced SSI. Univariate analysis showed that preoperative PNI (48.5 vs 51.7; p < 0.01), revision status (p < 0.05), male sex (p < 0.01), body mass index (BMI) (p < 0.05), and usage of anticoagulant agents (p < 0.05) differed significantly between the SSI and non-SSI groups. Multivariate logistic regression analysis showed that preoperative PNI (odds ratio [OR], 0.94; 95% confidence interval [CI]: 0.90-0.98; p < 0.01), male sex (OR, 2.64; 95% CI: 1.40-4.99; p < 0.01), length of surgery ≥ 180 min (OR, 2.78; 95% CI: 1.30-5.96; p < 0.01), BMI ≥ 30 kg/m2 (OR, 2.89; 95% CI: 1.20-6.97; p < 0.05), and revision status (OR, 2.30; 95% CI: 1.07-4.98; p < 0.05) were independently associated with SSI postoperatively. CONCLUSION: Lower preoperative PNI was found to be a risk factor for SSI after spine surgery. Patients with lower preoperative PNI values should be cautioned about the risk of SSI and provide adequate informed consent.

Association between the 25-question Geriatric Locomotive Function Scale score and the incidence of certified need of care in the long-term care insurance system: The TOEI study.

BACKGROUND: The Geriatric Locomotive Function Scale is a screening tool to identify the risk of locomotive syndrome in the elderly. We aimed to clarify the association of Geriatric Locomotive Function Scale scores with the incidence of certified need of care in the long-term care insurance system in a prospective longitudinal observational study (the TOEI Study). METHODS: Participants were individuals aged ≥50 years from a mountainous area who had undergone medical check-ups by the National Health Insurance in Toei. The Geriatric Locomotive Function Scale questionnaire, physical performance tests, and radiographs were completed by participants. The primary endpoint was the incidence of certified need of care in the long-term care insurance system. The secondary endpoint was the incidence of either one of the following events: certified need of care or death. RESULTS: We enrolled 681 subjects (271 men and 410 women). The mean age was 72.9 (range, 50-92) years. The incidences of certified need of care and either one of the two events were 104 and 130, respectively, during the average 4.9-year follow-up. The cumulative incidence rates of certified need of care by groups of the Geriatric Locomotive Function Scale, namely, Group 0 (score 0-6), Group 1 (score 7-15), and Group 2 (score 16-) were 7.5%, 14%, and 35%, respectively. The cumulative incidence rates of either one of the two events by group were 11%, 18%, and 39%, respectively. There was a significant association between higher Geriatric Locomotive Function Scale scores and survival rates (not achieved at each endpoint) for the primary and secondary endpoints. CONCLUSIONS: Higher Geriatric Locomotive Function Scale score was associated with greater incidence of certified need of care in the long-term care insurance system as well as either one of the two aforementioned events. This scale might enable prediction of prognosis among elderly patients.

Spinal shortening osteotomy for adult tethered cord syndrome evaluated by intraoperative ultrasonography.

BACKGROUND: Spinal shortening osteotomy (SSO) reduces the tension indirectly in the spinal cord and minimizes perioperative complications. However, the most effective and safe length to which the spine can be shortened is still unknown. In our practice, we use somatosensory-evoked potentials, motor-evoked potentials, and intraoperative ultrasonography when performing SSO. This study aimed to introduce the clinical outcomes of our SSO technique for tethered cord syndrome (TCS) in adults. METHODS: This retrospective study included 7 adult patients (2 males and 5 females) with TCS treated between December 2010 and December 2018. The average age and average preoperative duration were 40 and 5 years, respectively. All patients received SSO with somatosensory-evoked potentials, motor-evoked potentials, and ultrasonography. After surgery, all patients were followed for an average of 4 years. RESULTS: The mean operation time was 328 (284-414) min for SSO. The mean blood loss was 828 ml (501-1252 ml). Postoperative bony fusion was confirmed in all patients. Postoperative computed tomography (CT) demonstrated an average of 16 mm (11-20 mm) of spinal column shortening, compared with preoperative CT. Clinical improvements were obtained in all 7 cases, and there was no case of exacerbation. An indicator of shortening is that the ultrasonography gives pulsation and relaxation of the spinal cord. There were no abnormalities observed while monitoring the spinal cord. CONCLUSIONS: Spinal shortening should be done under somatosensory-evoked potentials, motor-evoked potentials, and intraoperative ultrasonography to obtain safe and sufficient shortening.

Characteristics affecting cervical sagittal alignment in patients with chronic low back pain.

BACKGROUND: Sagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP. METHOD: Of the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2-C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group). RESULTS: The prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637). CONCLUSIONS: This study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively. LEVEL OF EVIDENCE: Ⅳ.

Evaluation of the Central Sensitization Inventory Score in elderly adults with musculoskeletal examination.

OBJECTIVES: The present study aimed to conduct an epidemiological survey of Central Sensitization Inventory (CSI) scores in an older adult population and to investigate the association between the CSI scores, age, sex, pain intensity, site of pain, and health-related quality of life (QOL). METHODS: Participants were 373 Japanese adults aged ≥ 50 years who underwent a health checkup in 2018. We collected demographic data and clinical characteristics along with the CSI scores, QOL questionnaire, site of pain (neck, lower back, upper limb, and lower limb) and pain severity. We performed an epidemiological survey of the CSI scores and investigated the gender difference in CSI scores and the relationship between the CSI scores, site of pain, and QOL. RESULTS: The prevalence of low back pain was the highest (67.6%). The average CSI score was 14.2 points; 8% of volunteers had a high (> 30) CSI score. The CSI scores among women were significantly higher than those among men (p = .016). The CSI scores had a significantly moderate correlation with the numerical rating scale and QOL scores (all p < .001). Volunteers with neck pain showed the highest CSI scores (average 22.4 points). CONCLUSIONS: The CSI total score showed sex differences and had a significant correlation with pain severity and QOL. STUDY DESIGN: Cross-sectional study.

L5 pedicle subtraction osteotomy maintains good radiological and clinical outcomes in elderly patients with a rigid kyphosis deformity: a more than 2-year follow-up report.

PURPOSE: L5 pedicle subtraction osteotomy (PSO) is a demanding technique; thus, PSOs are usually performed at the L3/L4 level to correct the lack of lumbar lordosis. Mid- to long-term improvements in clinical outcomes after L5 PSO are unknown. We aimed to determine the efficacy and safety of L5 PSO for rigid kyphosis deformities. METHODS: We retrospectively reviewed the records of 57 patients with a rigid kyphosis deformity (mean age: 68 years) who underwent extensive corrective surgery incorporating PSO with a > 2-year follow-up. Radiographic parameters, postoperative complication rates, and the Oswestry Disability Index (ODI) scores were compared in the L5, L4, and L1-3 PSO groups preoperatively and at 1, 2, and 5 years postoperatively. RESULTS: There were 12, 25, and 20 patients in the L5, L4, and L1-3 PSO groups, respectively. Significant between-group differences were found in preoperative L4-S1 lordosis (L5:L4:L1-3 PSO groups = - 8.9°:8.9°:16.2°, P < 0.001). The surgeries improved the postoperative spinopelvic alignment (similar in all groups). There was no significant between-group difference in the postoperative complication rate; no irreversible complications occurred. In the L5 PSO group, there was one case of a common iliac vein injury. The ODI scores improved postoperatively in all groups; this was maintained for 5 years postoperatively. CONCLUSION: L5 PSO for L4-5/L5 kyphosis deformities resulted in adequate correction and ODI improvement, which were maintained up to 5 years postoperatively. The surgical invasiveness, complication rates, and long-term prognosis associated with L5 PSO were similar to those of PSOs performed at other levels.

Impact of adult spinal deformity corrective surgery in patients with the symptoms of gastroesophageal reflux disease: a 5-year follow-up report.

PURPOSE: Gastroesophageal reflux disease (GERD) is reported as one of the symptoms of adult spinal deformity (ASD). Little is known about the mid- to long-term improvement in GERD symptoms after ASD surgery. Therefore, this retrospective study from prospectively collected database aimed to investigate GERD symptoms in patients for a minimum of 2 years after ASD corrective surgery. METHODS: Records from 230 patients (mean age: 64 years) who underwent ASD surgery were examined using the frequency scale for the symptoms of GERD (FSSG) questionnaires for the diagnosis of GERD. FSSG scores and radiographic parameters were investigated preoperatively and postoperatively at 6 months and 1, 2, and 5 years. RESULTS: In total, 90 (39%) patients were preoperatively diagnosed with GERD defined by FSSG score ≥ 8 points. Radiographic results showed that the corrective surgeries improved local and global alignments. In the GERD patients, preoperative FSSG scores (16.1 ± 7.3 points) significantly improved to 7.7 ± 7.4 points within 6 months postoperatively (p < 0.001), and postoperative FSSG scores maintained at 1 year (9.9 ± 8.2 points, p = 0.061), 2 years (9.7 ± 8.2 points, p = 0.086), and 5 years (9.4 ± 8.0 points, p = 0.177). Among the GERD group, 62 patients (69%; improvement cases) showed improvement in GERD symptoms defined by FSSG score < 8 points within 6 months postoperatively. CONCLUSIONS: Among ASD patients, 39% were diagnosed with GERD. In 69% of these patients, GERD symptoms improved within 6 months of corrective surgery and maintained up to 5 years postoperatively. These slides can be retrieved under Electronic Supplementary Material.

Deterioration of sagittal spinal alignment with age originates from the pelvis not the lumbar spine: a 4-year longitudinal cohort study.

PURPOSE: There is controversy regarding age-related deterioration of spinal sagittal alignment in cross-sectional study. Although we reported that deterioration in spinal alignment originated at the cervical spine in males and the pelvis in females, others studies have indicated that the lumbar spine is initially implicated in both sexes. The purpose of this study was to clarify these differences in a longitudinal cohort study. METHODS: Our analysis was based on 237 individuals aged 60-89 years who participated in our health screening study in 2014 and 2018. They were classified into six groups by birth year and sex: 60-69 years (26 males, 49 females); 70-79 years (35 males, 88 females); and 80-89 years (19 males, 20 females). The following parameters were measured from standing radiographs: pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis, T1 slope, cervical lordosis, C7 sagittal vertical axis (C7 SVA), and C2-7 SVA. RESULTS: In males, the first significant change was an increase in the PT angle (19°, in 2014, to 21°, in 2018) in the 80-89 years age group (P < 0.05), with no significant deterioration in cervical parameters. In females, spinal deterioration included a change in the SS (32°-30°), PT (18°-20°), and SVA (- 8 to 6 mm) in the 60-69 years age group (P < 0.05), with no change in the LL. CONCLUSIONS: Contrary to prior studies, our longitudinal data indicated that deterioration in spinal alignment originates in the pelvis for both sex but develops earlier in females than males.

Correction to: Deterioration of sagittal spinal alignment with age originates from the pelvis not the lumbar spine: a 4-year longitudinal cohort study.

Unfortunately, figure 3 was incorrectly published in the original publication. The complete correct figure 3 is given below.

Implications of the diagnosis of locomotive syndrome stage 3 for long-term care.

Objectives: Locomotive syndrome stage 3 (LS3), which has been established recently, may imply a greater need for care than LS stage 0 (LS0), LS stage 1 (LS1), and LS stage 2 (LS2). The relationship between LS3 and long-term care in Japan is unclear. Therefore, this study aimed to examine this relationship. Methods: A total of 531 patients (314 women and 217 men; mean age, 75 years) who were not classified as requiring long-term care and underwent musculoskeletal examinations in 2012 were grouped according to their LS stage. Group L comprised patients with LS3 and Group N comprised those with LS0, LS1, and LS2. We compared these groups according to their epidemiology results and long-term care requirements from 2013 to 2018. Results: Fifty-nine patients (11.1%) were diagnosed with LS3. Group L comprised more patients (50.8%) who required long-term care than Group N (17.8%) (P < 0.001). Group L also comprised more patients with vertebral fractures and knee osteoarthritis than Group N (33.9% vs 19.5% [P = 0.011] and 78% vs 56.4% [P < 0.001], respectively). A Cox proportional hazards model and Kaplan-Meier analysis revealed a significant difference in the need for nursing care between Groups L and N (log-rank test, P < 0.001; hazard ratio, 2.236; 95% confidence interval, 1.451-3.447). Conclusions: Between 2012 and 2018, 50% of patients with LS3 required nursing care. Therefore, LS3 is a high-risk condition that necessitates interventions. Approaches to vertebral fractures and osteoarthritis of the knee could be key.

Preoperative Less Right Shoulder Elevation Had a Higher Risk of Postoperative Shoulder Imbalance When Main Thoracic Curve Shows Higher Correction Regardless of the Upper Instrumented Vertebra Level for Patients with Adolescent Idiopathic Scoliosis Lenke Type 1.

STUDY DESIGN: This is a retrospective study. PURPOSE: This study aimed to investigate the incidence of and risk factors for postoperative shoulder imbalance (PSI) in patients with Lenke type 1. OVERVIEW OF LITERATURE: PSI is a complication resulting in poor self-image and satisfaction in adolescent idiopathic scoliosis (AIS) patients. METHODS: We examined the data of AIS patients with Lenke type 1 curves who underwent posterior fusion surgery in a retrospective manner. PSI was defined as a 2-year postoperative absolute radiographic shoulder height (RSH) of ≥2 cm. Patients were divided into two groups based on the presence of PSI and the level of their upper instrumented vertebra (UIV) (UIV at T2 or T3 [U-UIV] or UIV below T3 [L-UIV]). The radiographic parameters and clinical outcomes were compared, and the cutoff values of risk factors were identified by multivariate analysis. RESULTS: Of 104 patients, 21 (20.2%) had left shoulder elevation PSI. The PSI group had a significantly greater preoperative RSH (-5.1 mm vs. -14.3 mm) and main thoracic (MT) curve correction rate (77.3% vs. 69.1%) than the non-PSI group. The PSI incidence did not differ between the U-UIV and L-UIV groups. Multivariate analysis identified preoperative RSH and the MT curve correction rate as independent risk factors for PSI. The receiver operating characteristic curve analysis identified the preoperative RSH cutoff value as -6.5 mm and MT curve correction rate cutoff value as 76.9%. CONCLUSIONS: Even in AIS patients with Lenke type 1 curves, the incidence of PSI was relatively high (20.2%). Patients with preoperative lower right shoulder elevation (i.e., RSH >-6.5 mm) had a higher risk of PSI regardless of UIV level when the MT curve showed a higher correction rate (i.e., correction rate >76.9%).

Postoperative neurological complications in intradural extramedullary tumors: A 10-year experience of a single center.

BACKGROUND: Intradural extramedullary spinal cord tumors (IDEMs) cause neurological symptoms due to compression of the spinal cord and caudal nerves. The purpose of this study was to investigate the incidence of postoperative neurological complications after surgical resection of IDEM and to identify factors associated with such postoperative neurological complications. METHODS: We retrospectively analyzed 85 patients who underwent tumor resection for IDEM between 2010 and 2020. We investigated the postoperative worsening of neurological disorders. The patients were divided into two groups: those with and without postoperative neurological complications. Patient demographic characteristics, tumor level, histological type, and surgery-related factors were also compared. RESULTS: The mean age at the time of surgery was 57.4 years, and histological analysis revealed 45 cases of schwannoma, 34 cases of meningioma, three cases of myxopapillary ependymoma, one case of ependymoma, one case of hemangioblastoma and one case of lipoma. There were five cases (5.8%) of postoperative neurological complications, and four patients improved within 6 months after surgery, and one patient had residual worsening. There were no statistically significant differences in age, sex, tumor location, preoperative modified McCormick Scale grade, histology, tumor occupancy, or whether fixation was performed in the presence or absence of postoperative neurological complications. All four cases of meningioma with postoperative neurological complications had preoperative neuropathy and meningiomas were located in the anterior or lateral thoracic spine. CONCLUSIONS: Neurological complications after surgical resection for IDEM occurred in 5.8% of patients. Meningiomas with postoperative neurological complications located anteriorly or laterally in the thoracic spine.

Longer Screws Can Reduce the Stress on the Upper Instrumented Vertebra With Long Spinal Fusion Surgery: A Finite Element Analysis Study.

STUDY DESIGN: A finite element analysis study. OBJECTIVE: Of proximal junctional failure, upper instrumented vertebra (UIV) fracture can causes severe spinal cord injury. Previously, we reported that higher occupancy rate of pedicle screw (ORPS) at UIV prevented UIV fracture in adult spinal deformity surgery; we had not yet tested this finding using a biomechanical study. The purpose of present study was to measure the differences in loads on the UIV according to the length of PS and ORPS. METHODS: We designed an FE model of a lumbar spine (L1-S1) using FE software. The PS was set from L2 to S1 and connected the rod. The FE model simulated flexion (8 Nm) to investigate the loads at UIV (L2) according to the length of the PS. There were 5 screw lengths examined: 40 (ORPS 36.4%), 45 (48.5%), 50 (66.7%), 55 (81.8%), and 60 mm (93.9%). RESULTS: Stress with bending motion was likely to occur at the upper front edge of the vertebral body, the pedicles, and the screw insertion point. The maximum equivalent stress according to screw lengths of 40, 45, 50, 55, and 60 mm were 45.6, 37.2, 21.6, 13.3, and 14.8 MPa, respectively. The longer screw, the less stress was applied to UIV. No remarkable change was observed between the screw lengths of 55 and 60 mm. CONCLUSIONS: Increasing ORPS to 81.8% or more reduced the load on the UIV. To prevent UIV fracture, the PS length in the UIV should be more than ORPS 81.8%.