Hidden blood loss in extreme lateral interbody fusion for adult spinal deformity.

BACKGROUND: Extreme lateral interbody fusion (XLIF) is often used with posterior spinal fixation (PSF) to treat adult spinal deformity (ASD). However, the amount of intraoperative blood loss (IBL) reported for XLIF may underestimate the total blood loss (TBL). The objective of this study was to determine the total perioperative blood loss in XLIF for ASD. METHODS: We assessed 30 consecutive ASD patients with Schwab-SRS type L (mean age: 68.7 ± 8.2 years; mean follow-up 2.0 ± 1.3 years) who were treated by multilevel XLIF (mean, 2.5 ± 0.6 levels) followed by PSF after 3-5 days. We calculated the TBL after XLIF by the Gross equation, by hemoglobin (Hb) balance, and by the Orthopedic Surgery Transfusion Hemoglobin European Overview (OSTHEO) formula. We defined hidden blood loss (HBL) as the difference between the TBL and IBL. Pearson correlation, Spearman correlation, and multiple logistic regression analysis were performed to investigate the risk factors related to HBL. RESULTS: Post-XLIF blood tests showed a significant decrease in the Hb (from 11.8 ± 1.1 mg/dl to 10.6 ± 1.1 mg/dl) and hematocrit (from 36.0 ± 3.2% to 32.5 ± 3.2%). Although the mean IBL was relatively small (33 ± 52 mL), we calculated the TBL as 291 ± 171 mL (Gross equation) and the HBL as 258 ± 168 mL by Gross equation, which was 8 times greater than the IBL on average. There was no difference in the results obtained using the three methods. Multiple logistic regression analysis indicated preoperative lumber lordosis was the risk factor of high HBL (Odds ratio = 1.085, 95%CI: 1.006-1.170, p = 0.035). CONCLUSIONS: The HBL in XLIF was 8 times greater than the IBL. During the perioperative course of correction and fusion surgery for ASD with XLIF, surgeons need to pay attention not to underestimate the TBL.

Clinical outcomes and a therapeutic indication of intramedullary spinal cord astrocytoma.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Although intramedullary astrocytoma is associated with a high mortality rate, the optimal treatment has not reached a consensus. This study aimed at evaluating neurologic function and overall survival rate (OSR) in the treatment of this tumor. SETTING: The single institution in Japan. METHODS: This study enrolled 67 subjects who underwent surgical treatment for intramedullary astrocytoma. Demographic, imaging, and surgical information were collected from each participant. Tumors were histologically categorized using the World Health Organization classification, and subjects were divided into low-grade (I and II; n = 40) and high-grade (III and IV; n = 27) groups. Neurologic status was evaluated using the modified McCormick scale (MMS). OSR was assessed using Kaplan-Meier methods. RESULTS: The OSR decreased when the pathological grade increased (p < 0.01). Regarding the therapeutic efficacy for low-grade astrocytomas, subjects who underwent gross total resection (GTR) showed a higher OSR than those who did not (p = 0.02). GTR prevented worsening of MMS score, while non-GTR increased the MMS score (p < 0.01). In the high-grade group, 19 and 10 underwent radiation therapy and chemotherapy, respectively. However, both treatments did not improve OSR. Cordotomy was performed for subjects whose lesional area was at the thoracic level, but the OSR did not significantly increase. CONCLUSIONS: The most beneficial therapeutic strategy for low-grade astrocytomas was GTR, whereas that for the high-grade tumors was unclear. Further studies with a larger sample size are warranted to validate the effective treatment for malignant astrocytomas.

K-line (-) in the neck-flexed position negatively affects surgical outcome of expansive open-door laminoplasty for cervical spondylotic myelopathy.

BACKGROUND: The K-line in the neck-flexed position (FK-line) on radiography reflects dynamic factors and cervical alignment. Although the FK-line has been reported to affect the neurological recovery after muscle-preserving selective laminectomy for cervical spondylotic myelopathy (CSM), its influence on surgical outcomes after expansive open-door laminoplasty (ELAP) has not been investigated. METHODS: We reviewed the surgical outcomes in 81 patients with multilevel CSM who underwent C4-C6 ELAP combined with C3 and C7 partial laminectomy using a laminoplasty plate and were followed up for at least 2 years. We defined the K-line (-) as some portion of a bony spur or the vertebral body crossing the FK-line, whereas the FK-line (+) was defined as that never crossing the FK-line. Patients were divided into the FK-line (+) (n = 61) and FK-line (-) groups (n = 20), and the surgical outcomes were compared between the groups. A multivariate analysis was performed to identify the factors that influenced the neurological outcomes. RESULTS: The FK-line (-) group had a smaller C2-C7 angle, smaller C7 slope, greater postoperative increase in the C2-C7 sagittal vertical axis, greater kyphosis in cervical flexion and less lordosis in cervical extension, and higher incidence of postoperative residual spinal cord compression. The preoperative-to-postoperative changes in the Japanese Orthopedic Association (JOA) score and JOA score recovery rate (RR) were lower in the FK-line (-) group. The multiple linear regression analysis revealed that the K-line (-) (ß = -0.327, P = 0.011) and high signal intensity (SI) changes on T2-weighted imaging (WI) combined with the low SI changes on T1-WI in the spinal cord (ß = -0.320, P = 0.013) negatively affected the JOA score RR. CONCLUSIONS: The FK-line can be used for patients with CSM as a simple indicator of neurological outcomes after ELAP.

The impact of diabetes mellitus on spinal fracture with diffuse idiopathic skeletal hyperostosis: A multicenter retrospective study.

BACKGROUND: Patients with diffuse idiopathic skeletal hyperostosis (DISH) are susceptible to spinal column injuries with neurological deterioration. Previous studies indicated that the prevalence of diabetes mellitus (DM) in patients with DISH was higher than that in patients without DISH. This study investigates the impact of DM on surgical outcomes for spinal fractures in patients with DISH. METHODS: We retrospectively evaluated 177 spinal fractures in patients with DISH (132 men and 45 women; mean age, 75 ± 10 years) who underwent surgery from a multicenter database. The subjects were classified into two groups according to the presence of DM. Perioperative complications, neurological status by Frankel grade, mortality rate, and status of surgical site infection (SSI) were compared between the two groups. RESULTS: DM was present in 28.2% (50/177) of the patients. The proportion of men was significantly higher in the DM group (DM group: 86.0% vs. non-DM group: 70.1%) (p = 0.03). The overall complication rate was 22.0% in the DM group and 19.7% in the non-DM group (p = 0.60). Poisson regression model revealed that SSI was significantly associated with DM (DM group: 10.0% vs. non-DM group: 2.4%, Relative risk: 4.5) (p = 0.048). Change in neurological status, mortality rate, instrumentation failure, and nonunion were similar between both groups. HbA1c and fasting blood glucose level (SSI group: 7.2% ± 1.2%, 201 ± 67 mg/dL vs. non-SSI group: 6.6% ± 1.1%, 167 ± 47 mg/dL) tended to be higher in patients with SSI; however, there was no significant difference. CONCLUSIONS: In spinal fracture in patients with DISH, although DM was an associated factor for SSI with a relative risk of 4.5, DM did not negatively impact neurological recovery. Perioperative glycemic control may be useful for preventing SSI because fasting blood glucose level was high in patients with SSI.

Baseline severity of myelopathy predicts neurological outcomes after posterior decompression surgery for cervical spondylotic myelopathy: a retrospective study.

STUDY DESIGN: Retrospective multicenter study. OBJECTIVES: To identify the usefulness of the baseline severity of myelopathy for predicting surgical outcomes for cervical spondylotic myelopathy (CSM). SETTING: Seventeen institutions in Japan. METHODS: This study included 675 persons with CSM who underwent posterior decompression. According to baseline severity, the individuals were divided into the mild (Japanese Orthopaedic Association [JOA] score ≥ 14.5), moderate (JOA score = 10.5-14), and severe (JOA score ≤ 10) groups. Surgical outcomes and clinical variables were compared between the groups. Logistic regression analysis was used to develop a prediction model for unsatisfactory symptom state (postoperative JOA score ≤ 14, residual moderate or severe myelopathy). RESULTS: The mean (±standard deviation) age was 67 ± 12 years. The participants in the severe group were older than those in the mild group. Postoperative JOA scores were higher in the mild group than in the severe group. According to multivariate logistic regression analysis, the prediction model included preoperative JOA scores (odds ratio [OR] 0.60; 95% confidence interval [CI] 0.55-0.67) and age (OR 1.06, 95% CI 1.04-1.08). On the basis of the model, a representative combination of the thresholds to maximize the value of "sensitivity - (1 - specificity)" demonstrated a preoperative JOA score of 11.5 as a predictor of postoperative unsatisfactory symptom state in people around the mean age of the study cohort (67 years). CONCLUSIONS: The combination of the baseline severity of myelopathy and age can predict postoperative symptom states after posterior decompression surgery for CSM.

The effectiveness of chemonucleolysis with condoliase for treatment of painful lumbar disc herniation.

BACKGROUND: Chemonucleolysis with condoliase, which degrades chondroitin sulfate, could be a new, minimally invasive therapeutic option for patients with lumbar disc herniation (LDH). The purpose of this study was to analyze prognostic factors for clinical outcomes in LDH patients subjected to chemonucleolysis with condoliase. METHODS: Inclusion criteria for this procedure were 1) 18-70 years of age; 2) unilateral leg pain and positive straight leg raise (SLR) (<70°) or femoral nerve stretching test; 3) subligamentous extrusion verified on magnetic resonance imaging; 4) neurological symptoms consistent with a compressed nerve root on magnetic resonance imaging (MRI) images; and 5) minimum six months of follow-up. In total, 82 patients (55 men, 27 women; mean age, 47.2 ± 15.5 years; mean follow-up, 9.1 ± 3.0 months) who underwent chemonucleolysis with condoliase for painful LDH were included. An improvement of 50% or more in the Visual analogue scale (VAS) of leg pain was classified as effective. RESULTS: Seventy patients (85.4%) were classified into the effective (E) group and 12 patients (14.6%) into the less-effective (L) group. Surgical treatment was required in four patients. No severe adverse complications were reported; 41.3% of the patients developed disc degeneration of Pfirrmann grade 1 or more at the injected disc level. Univariate analysis revealed that young age (p = 0.036), without history of epidural or nerve root block (p = 0.024), and injection into the central portion of the intervertebral disc (p = 0.014) were significantly associated with clinical effectiveness. A logistic regression analysis revealed that injection into the central portion of the intervertebral disc (p = 0.049; odds ratio, 4.913; 95% confidence interval, 1.006-26.204) was significantly associated with clinical effectiveness. CONCLUSIONS: Chemonucleolysis with condoliase is a safe and effective treatment for painful LDH; 85.4% of the patients showed improvement after the treatment without severe adverse events. To obtain the best outcome, condoliase should be injected into the center of the intervertebral disc.

Risk predictors of perioperative complications for the palliative surgical treatment of spinal metastasis.

BACKGROUND: The complication rate for palliative surgery in spinal metastasis is relatively high, and major complications can impair the patient's activities of daily living. However, surgical indications are determined based primarily on the prognosis of the cancer, with the risk of complications not truly considered. We aimed to identify the risk predictors for perioperative complications in palliative surgery for spinal metastasis. METHODS: A multicentered, retrospective review of 195 consecutive patients with spinal metastasis who underwent palliative surgeries with posterior procedures from 2001 to 2016 was performed. We evaluated the type and incidence of perioperative complications within 14 days after surgery. Patients were categorized into either the complication group (C) or no-complication group (NC). Univariate and multivariate analyses were used to identify potential predictors for perioperative complications. RESULTS: Thirty patients (15%) experienced one or more complications within 14 days of surgery. The most frequent complications were surgical site infection (4%) and motor weakness (3%). A history of diabetes mellitus (C; 37%, NC; 9%: p < 0.01) and surgical time over 300 min (C; 27%, NC; 12%: p < 0.05) were significantly associated with complications according to univariate analysis. Increased blood loss and non-ambulatory status were determined to be potential risk factors. Of these factors, multivariate logistic regression revealed that a history of diabetes mellitus (OR: 6.6, p < 0.001) and blood loss over 1 L (OR: 2.7, p < 0.05) were the independent risk factors for perioperative complications. There was no difference in glycated hemoglobin A1c between the diabetes patients with and without perioperative complications. CONCLUSIONS: Diabetes mellitus should be used for the risk stratification of surgical candidates regardless of the treatment status, and strict prevention of bleeding is needed in palliative surgeries with posterior procedures to mitigate the risk of perioperative complications.

Risk factors for delayed diagnosis of spinal fracture associated with diffuse idiopathic skeletal hyperostosis: A nationwide multiinstitution survey.

BACKGROUND: Patients with DISH are susceptible to spinal fractures and subsequent neurological impairment, including after minor trauma. However, DISH is often asymptomatic and fractures may have minimal symptoms, which may lead to delayed diagnosis. The purpose of this study was to identify risk factors for delayed diagnosis of spinal fractures in patients with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: The subjects were 285 patients with DISH surgically treated at 18 medical centers from 2005 to 2015. Cause of injury, imaging findings, neurological status at the times of injury and first hospital examination, and the time from injury to diagnosis were recorded. A delayed diagnosis was defined as that made >24 h after injury. RESULTS: Main causes of injury were minor trauma due to a fall from a standing or sitting position (51%) and high-energy trauma due to a fall from a high place (29%) or a traffic accident (12%). Delayed diagnosis occurred in 115 patients (40%; 35 females, 80 males; mean age 76.0 ± 10.4 years), while 170 (60%; 29 females, 141 males; mean age 74.6 ± 12.8 years) had early diagnosis. Delayed group had a significantly higher rate of minor trauma (n = 73, 63% vs. n = 73, 43%), significantly more Frankel grade E (intact neurological status) cases at the time of injury (n = 79, 69% vs. n = 73, 43%), and greater deterioration of Frankel grade from injury to diagnosis (34% vs. 8%, p < 0.01). In multivariate analysis, a minor trauma fall (OR 2.08; P < 0.05) and Frankel grade E at the time of injury (OR 2.29; P < 0.01) were significantly associated with delayed diagnosis. CONCLUSION: In patients with DISH, it is important to keep in mind the possibility of spinal fracture, even in a situation in which patient sustained only minor trauma and shows no neurological deficit. This is because delayed diagnosis of spinal fracture can cause subsequent neurological deterioration.

The factors related to the poor ADL in the patients with osteoporotic vertebral fracture after instrumentation surgery.

PURPOSE: Osteoporotic vertebral fracture (OVF) with nonunion or neurological deficit may be a candidate for surgical treatment. However, some patients do not show improvement as expected. Therefore, we conducted a nationwide multicenter study to determine the predictors for postoperative poor activity of daily living (ADL) in patients with OVF. METHODS: We retrospectively reviewed the case histories of 309 patients with OVF who underwent surgery. To determine the factors predicting postoperative poor ADL, uni- and multivariate statistical analyses were performed. RESULTS: The frequency of poor ADL at final follow-up period was 9.1%. In univariate analysis, preoperative neurological deficit (OR, 4.1; 95% CI, 1.8-10.3; P < 0.001), perioperative complication (OR, 3.4; P = 0.006), absence of preoperative bone-modifying agent (BMA) administration (OR, 2.7; P = 0.03), and absence of postoperative recombinant human parathyroid hormone (rPTH) administration (OR, 3.9; P = 0.006) were significantly associated. In multivariate analysis, preoperative neurological deficit (OR, 4.6; P < 0.001), perioperative complication (OR, 3.4; P = 0.01), and absence of postoperative rPTH administration (OR, 3.9; P = 0.02) showed statistical significance. CONCLUSIONS: Preoperative neurological deficit, perioperative complication, and absence of postoperative rPTH administration were considered as predictors for postoperative poor ADL in patients with OVF. Neurological deficits and complications are often inevitable factors; therefore, rPTH is an important option for postoperative treatment for OVF. These slides can be retrieved under Electronic Supplementary Material.

Excessive correction impacts postoperative shoulder imbalance in lenke type 5C adolescent idiopathic scoliosis.

BACKGROUND: Postoperative shoulder imbalance (PSI) has a negative impact on the surgical outcomes of patients with adolescent idiopathic scoliosis. This study aimed to evaluate the risk factors of PSI in patients with Lenke type 5C curves. METHODS: This study included 100 patients who underwent posterior correction surgery using pedicle screw constructs for Lenke type 5C curves. The mean age of the patients at surgery was 15.5 ± 2.3 years, and the mean follow-up period was 36.6 ± 15.0 months. The subjects were classified into the following two groups: PSI and non-PSI. Radiographic parameters, including the preoperative and 2-year postoperative coronal and sagittal profiles, were compared between the two groups. RESULT: PSI was found in eight patients (8.0%). The preoperative Cobb angles were 47.3° ± 8.7° and 48.0° ± 3.9° in the non-PSI and PSI groups, respectively. The correction rate in the PSI group was significantly higher than that in the non-PSI group (81.0% ± 17.7% vs. 67.7% ± 14.7%; p = 0.018). The preoperative T1 tilt angle in the PSI group was significantly larger than that in the non-PSI group (6.1° ± 3.3° vs. 3.1° ± 2.8°; p = 0.005). Receiver operating characteristic (ROC) analysis showed that the area under the ROC curve was 0.769 (p = 0.012, 95% confidence interval [CI], 0.556-0.982) and 0.763 (p = 0.014, 95% CI, 0.598-0.928) for the correction rate and preoperative T1 tilt, respectively. The cut-off value was 73% and 4° for the correction rate and preoperative T1, respectively. CONCLUSION: PSI was found in 8.0% of Lenke type 5C curves. Excessive correction of the lumbar curve of >73% and preoperative T1 tilt of >4° can be risk factors for PSI in patients with Lenke type 5C curve.

Potential association of metabolic and musculoskeletal disorders with lumbar intervertebral disc degeneration: Cross-sectional study using medical checkup data.

BACKGROUND: The pathogenesis of intervertebral disc (IVD) degeneration is complex and involves the interaction of multiple factors. However, few systemic studies have explored the associations of metabolic disorders and age-related musculoskeletal disorders with the development of IVD degeneration. METHODS: We analyzed clinical data obtained from healthy individuals who had undergone a musculoskeletal checkup. In total, 276 subjects comprising 142 males and 134 females were enrolled. The subjects were divided into two groups based on the degree of IVD degeneration according to Pfirrmann grading: those with grades 1-3, the group with non-degenerative discs; and grades 4 and 5, the group with degenerative discs. The subjects underwent examinations including abdominal circumference, blood pressure, bilateral hand grip strength, abdominal computed tomography, magnetic resonance imaging of the lumbar spine, and dual X-ray absorptiometry. To examine the independent association with IVD degeneration at L3/4, L4/5, and L5/S levels, we constructed a Poisson regression model and estimated relative risks (RRs) and 95% confidence intervals (CIs) of IVD degeneration. RESULTS: Multivariable analysis showed that advanced age was markedly associated with IVD degeneration at all levels and that men had an inverse association with the IVD degeneration, particularly at the L4/5 level (RR = 0.7, 95% CI = 0.6-0.9). In addition, metabolic syndrome was significantly associated with IVD degeneration at the L5/S level (RR = 1.4, 95% CI = 1.1-1.8). Meanwhile, sarcopenia showed no significant association with IVD degeneration at any level. Osteoporosis was inversely associated with IVD degeneration, particularly at the L4/5 level (RR = 0.7, 95% CI = 0.6-0.9). CONCLUSIONS: Our data suggest that advanced age, female sex, and metabolic syndrome are associated with IVD degeneration. In addition, osteoporosis showed an inverse association with IVD degeneration. Our data should promote understanding of the etiology of lumbar IVD degeneration.

Lumbar spinal surgery improves locomotive syndrome in elderly patients with lumbar spinal canal stenosis: A multicenter prospective study.

BACKGROUND: Owing to musculoskeletal dysfunction, locomotive syndrome elevates the risk of requiring nursing care. Among degenerative musculoskeletal disorders, lumbar spinal canal stenosis (LSS) associates with locomotive syndrome; however, whether lumbar spinal surgery for LSS improves locomotive syndrome remains unclear. Hence, this study aimed to identify the efficacy of lumbar spinal surgery on locomotive syndrome among elderly patients with LSS. METHODS: We prospectively collected the clinical data from multiple institutions of patients (age >65 years) who underwent lumbar spinal surgery. Patients were examined for the locomotive syndrome risk test, including the stand-up Test, the two-step Test, and the 25-question risk assessment, 1-day preoperatively and 6-month and 1-year postoperatively. Using a logistic regression model, we identified factors associated with improvement of locomotive syndrome in the total assessment. RESULTS: Overall, we examined the data of 166 patients in this study. Upon converting each score of three tests to the stage of locomotive syndrome, the two-step test and the 25-question risk assessment revealed marked improvement in the postoperative distribution of stages. However, the stand-up test revealed a comparable distribution of stages pre- and postoperatively. In the total assessment, the postoperative distribution of stages was significantly improved than that preoperatively. The multivariable analysis revealed that failed back surgery syndrome [odds ratio (OR), 0.2; 95% confidence interval (CI): 0.04-1.05; P = 0.057)] and preoperative stage of 2 in stand-up test (OR, 0.2; 95% CI: 0.05-1.02; P = 0.054) tended to have inverse association with postoperative improvement of locomotive syndrome in the total assessment. CONCLUSIONS: Lumbar spinal surgery improved the stage of locomotive syndrome among elderly patients with LSS. This study suggests that lumbar spinal surgery for LSS could be beneficial in alleviating locomotive syndrome.

Predictive model for major complications 2 years after corrective spine surgery for adult spinal deformity.

PURPOSE: ASD surgery improves a patient's health-related quality of life, but it has a high complication rate. The aim of this study was to create a predictive model for complications after surgical treatment for adult spinal deformity (ASD), using spinal alignment, demographic data, and surgical invasiveness. METHODS: This study included 195 surgically treated ASD patients who were > 50 years old and had 2-year follow-up from multicenter database. Variables which included age, gender, BMI, BMD, frailty, fusion level, UIV and LIV, primary or revision surgery, pedicle subtraction osteotomy, spinal alignment, Schwab-SRS type, surgical time, and blood loss were recorded and analyzed at least 2 years after surgery. Decision-making trees for 2-year postoperative complications were constructed and validated by a 7:3 data split for training and testing. External validation was performed for 25 ASD patients who had surgery at a different hospital. RESULTS: Complications developed in 48% of the training samples. Almost half of the complications developed in late post-op period, and implant-related complications were the most common complication at 2 years after surgery. Univariate analyses showed that BMD, frailty, PSO, LIV, PI-LL, and EBL were risk factors for complications. Multivariate analysis showed that low BMD, PI-LL > 30°, and frailty were independent risk factors for complications. In the testing samples, our predictive model was 92% accurate with an area under the receiver operating characteristic curve of 0.963 and 84% accurate in the external validation. CONCLUSION: A successful model was developed for predicting surgical complications. Our model could inform physicians about the risk of complications in ASD patients in the 2-year postoperative period. These slides can be retrieved under Electronic Supplementary Material.

Impact of lumbar hypolordosis on the incidence of symptomatic postoperative spinal epidural hematoma after decompression surgery for lumbar spinal canal stenosis.

PURPOSE: Potential associations between radiographic parameters and the incidence of symptomatic postoperative spinal epidural hematoma (PSEH) have not been identified. This study aimed to identify risk factors including radiographic parameters for symptomatic PSEH after posterior decompression surgery for lumbar spinal canal stenosis (LSS). METHODS: We retrospectively reviewed 1007 consecutive patients who underwent lumbar decompression surgery for lumbar spinal canal stenosis (LSS) at our institution. We identified 35 cases of symptomatic PSEH, defined by clinical symptoms and MRI findings, and selected 3 or 4 age- and sex-matched control subjects for each PSEH subject (124 controls). We compared radiographic parameters and previously reported risk factors between PSEH and control subjects. RESULTS: Compared to the control group, PSEH patients had significantly higher preoperative systolic (p = .020) and diastolic (p = .048) blood pressure, and more levels of decompression (p = .001). PSEH and control subjects had significant differences in lumbar lordosis (PSEH 24.8° ± 14.6°, control 34.8° ± 14.5°), pelvic tilt (25.1° ± 11.7° vs. 20.8° ± 8.4°), sacral slope (23.4° ± 9.4° vs. 27.6° ± 8.3°), and pelvic incidence minus lumbar lordosis (23.7° ± 15.0° vs. 13.7° ± 14.6°). Multivariate analysis revealed two significant risk factors for PSEH: decompression of two or more levels and lumbar lordosis < 25°. CONCLUSIONS: Multilevel decompression and hypolordosis are significant risk factors for symptomatic PSEH after decompression surgery for LSS. LSS patients with lumbar hypolordosis or multilevel stenosis should be carefully observed for PSEH after decompression surgery. These slides can be retrieved under Electronic Supplementary Material.

Impact of fusion for adolescent idiopathic scoliosis on lung volume measured with computed tomography.

PURPOSE: Although lung volume (LV) can be measured directly by computed tomography (CT), the literature regarding CT-assessed LV in adolescent idiopathic scoliosis (AIS) patients is limited, and the influence of posterior spinal fusion with instrumentation (PSF) on LV has not been established. This study aimed to identify factors associated with decreased LV after PSF in AIS patients. METHODS: We retrospectively reviewed 111 consecutive AIS patients who were between 10 and 20 years of age and were treated by PSF at our facility. We assessed age at surgery, sex, height, body weight, Risser stage, Lenke classification, radiographic parameters, pulmonary function tests, and LV. Factors associated with a postoperative decrease in LV were identified by multivariable analysis. RESULTS: The mean total LV had increased at the 2-year follow-up, although marginally significant (p = .06), and there was a significant increase in the left LV (p = .01) but not the right LV (p = .25). We observed a postoperative reduction in total LV, defined as a total LV postoperative/preoperative ratio < 0.9, in 20 of the 111 patients (18.0%). Univariable analysis showed a significant correlation between ≥ 11 fusion levels and postoperative LV reduction (OR 3.11, 95% CI 1.13-8.57). This factor remained significant in the multivariable analysis, which yielded an adjusted OR of 2.82 (95% CI 1.01-7.93) for postoperative LV reduction in patients with ≥ 11 fusion levels. CONCLUSION: Our data suggest that a longer fusion area is associated with postoperative LV reduction. Therefore, avoidance of a longer fusion area of ≥ 11 will be preferable for preserving LV. These slides can be retrieved under Electronic Supplementary Material.

Clinical indicators of surgical outcomes after cervical single open-door laminoplasty assessed by the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The old-version JOA score for cervical myelopathy (CM) is an evaluation system performed by medical providers that focuses only on neurological function. The purpose of this study was to evaluate patient-reported outcomes using the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and to clarify clinical factors that affect the therapeutic effectiveness for CM. SETTING: Single institute in Japan. METHODS: We reviewed surgical outcomes for 126 CM patients who were treated by single open-door laminoplasty and were followed at least 2 years. We assessed clinical information, JOACMEQ, JOA scores, and radiographic parameters. Patients were grouped according to effective or ineffective surgical outcomes as defined by the JOACMEQ using logistic regression analyses. RESULTS: Laminoplasty resulted in functional improvement in the cervical spine and extremities for 40-50% of the patients, while bladder function showed only minimal recovery. Multivariable analyses revealed that a significant postoperative reduction in neck or shoulder pain influenced the effective functional recovery of the cervical spine. A reduction in arm or hand pain favorably affected the postoperative upper extremity function. Lower age and a postoperative decrease in limb pain were correlated with significantly improved function of the lower extremities. A postoperative reduction in arm pain enhanced the QOL recovery. CONCLUSIONS: The JOACMEQ makes it possible to analyze multiple aspects of surgical outcomes for patients who undergo cervical spine surgery. Open-door laminoplasty did not provide favorable results for some patients, which highlights the importance of assessing the indications for this procedure and managing postoperative pain.

Changes in sagittal alignment after surgical excision of thoracic spinal cord tumors in adults.

STUDY DESIGN: Retrospective chart audit. OBJECTIVES: This study investigated changes in sagittal alignment in adults after excision of thoracic spinal cord tumors without spinal fixation. SETTING: Single-center study at an academic orthopedic department in Japan. METHODS: We retrospectively reviewed records for 32 adults who underwent excision of thoracic spinal cord tumors by multilevel laminectomies without fixation. The participants were divided according to whether the tumor was in the upper (T1-4), middle (T5-8), or lower (T9-12) thoracic spine. We analyzed parameters such as age, sex, time in surgery and estimated blood loss, follow-up period, and preoperative and follow-up the Japanese Orthopaedic Association (JOA) scores and radiographs. RESULTS: Postoperative T1-12 kyphotic changes did not correlate with age, the number of resected laminae, or preoperative T1-12 kyphosis. JOA recovery rates were similar regardless of the tumor location. Participants with tumors in the upper thoracic spine had significant postoperative increases in T1-4 kyphosis, T1 slope (p < .05, respectively). In contrast, there were no significant changes in alignment in participants with tumors in the middle or lower thoracic spine. CONCLUSION: Even without fixation, sagittal alignment did not change after surgery to excise tumors in the middle and lower thoracic spine, indicating that fixation may not be necessary when excising spinal cord tumors in this region. In contrast, postoperative kyphosis may increase when the tumor is in the upper thoracic spine.

Lumbar spinal canal stenosis in patients with diffuse idiopathic skeletal hyperostosis: Surgical outcomes after posterior decompression surgery without spinal instrumentation.

BACKGROUND: To evaluate surgical outcomes after posterior decompression surgery for lumbar spinal canal stenosis (LSS) in patients with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: The patients (n = 184; 132 males and 52 females; mean age 72.0 years; mean follow-up 30.7 months) who underwent posterior decompression surgery for LSS were identified and classified as either DISH (D) or non-DISH (N) based on whole spine radiograph findings. Data on age, gender, American Society of Anesthesiologists (ASA) classification, operation time, and estimated blood loss, were evaluated, while radiographic parameters were measured from radiographs obtained pre- and post-operatively. RESULTS: Mean age and ASA classification were comparable between the two groups, while the proportion of males was significantly higher in the D group (87.5%) than in the N group (67.6%) (p = 0.016). Further, mean operation time was longer in the D group (89.0 min) than in the N group (73.7 min) (p = 0.036) and mean estimated blood loss was larger in the D group (98.7 g) than in the N group (51.9 g) (p = 0.006). At two years after surgery, the development of anterior translation was significantly higher in the D group (33.3%) than in the N group (17.3%) (p = 0.021). Improvements in ODI and SF-8 after the surgery were better in the N group than in the D group. CONCLUSIONS: Compared to LSS patients without DISH who also underwent posterior decompression surgery for LSS, surgery in patients with DISH was characterized by greater blood loss, longer operation time, increased translation at the decompressed segment, and poor recovery.

Lumbar spinal canal stenosis leads to locomotive syndrome in elderly patients.

BACKGROUND: Locomotive syndrome is a condition in which the ability to lead a normal life is restricted owing to a dysfunction in one or more of the parts of the musculoskeletal system. Although lumbar spinal canal stenosis (LSS) is considered to cause locomotive syndrome, a detailed assessment of the association between two pathologies has not yet been reported. METHODS: The clinical data of patients aged > 65 years old who planned to undergo surgery for LSS at multiple institutions were prospectively collected from April 2016 to August 2017. A total of 200 participants comprising 120 men and 80 women were enrolled in this study. Association of severity of LSS evaluated by Zurich Claudication Questionnaire scores with three locomotive syndrome risk tests (Stand-up Test, the Two-step Test, and a 25-question risk assessment) and Timed Up-and-Go Test were evaluated. RESULTS: In the total assessment of locomotive syndrome, 96.5% of the participants were diagnosed as grade 2, and the remaining 3.5% were diagnosed as grade 1. When the participants were divided into 3 groups according to the LSS severity, the scores of all locomotive syndrome risk tests were significantly worse with increasing LSS severity. Logistic regression analysis revealed that LSS severity was positively correlated with the risk level of locomotive syndrome evaluated by the Two-step Test (OR = 3.45, CI = 1.33-8.96). CONCLUSIONS: All LSS patients with surgical indications were diagnosed as having locomotive syndrome. In addition, our results indicated that LSS severity is potentially associated with the progression of locomotive syndrome. The treatment of LSS may be beneficial in alleviating the risk for locomotive syndrome.

Spinal fractures in patients with diffuse idiopathic skeletal hyperostosis: Clinical characteristics by fracture level.

BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) makes the spine prone to unstable fractures with neurological deterioration. This study was conducted to assess clinical and radiographic features of spinal fractures in DISH by the level of spinal injury, and to evaluate the optimal treatment for each level. METHODS: A multicenter retrospective study over a 5-year period, including 46 patients (35 males; 11 females) with a mean age of 77.2 ± 9.7 years at the time of injury. By fracture level, there were 7 cervical (15.2%), 25 thoracic (54.3%), and 14 lumbar (30.4%) fractures. We recorded the cause of injury, whether diagnosis was delayed, and neurological status by Frankel grade. Ossification and fracture patterns were assessed by CT-multi-planar reconstruction (MPR). RESULTS: Neurological status immediately after the cervical-spine injury was C (28.6%) or E (71.4%); after thoracic injury, C (12.0%) or E (88.0%); and after lumbar injury, D (21.4%) or E (78.6%). Inability to walk at admission was more frequent in patients with a spinal-cord injury above the lumbar level (P = .033). Vertebral-body fractures were observed in 14.3% of the cervical injuries, 80.0% of the thoracic injuries, and 50.0% of the lumbar injuries (P = .004). Most patients with a cervical fracture had a disc-level fracture (85.7%). Posterior-column ankylosis was observed in 14.3% of the cervical-fracture group, 72.0% of the thoracic-fracture group, and 78.6% of the lumbar-fracture group (P = .008). CONCLUSION: Ossification and fracture patterns in patients with DISH varied distinctly by the level of spinal injury. Intervertebral-disc fractures were frequently observed in the cervical spine. Delayed diagnosis, vertebral-body fracture, and posterior-column ankylosis were observed in the thoracolumbar spine. This study recommends 3 above and 3 below fusion, to avoid instrumentation failure in the fixation of spinal fracture in patients with DISH.