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A 12-year-old girl underwent surgery for Lenke type 4 adolescent idiopathic scoliosis. After scoliosis correction, the transcranial motor-evoked potential (Tc-MEP) showed no alarm. However, the Tc-MEP amplitude had declined ~10 min after correction, with a normal blood pressure (BP) and body temperature and without any technical monitoring errors. Therefore, we suspected indirect spinal cord ischaemia because of the delayed true-positive Tc-MEP alarm. All the strong corrections made loss of Tc-MEP and all the correction releases made recovers of waveform. Finally, a weak correction was performed, and the Tc-MEP amplitude was recovered. Because transient spinal cord ischaemia due to correction of triple curves may cause a delayed monitoring alarm, the monitoring team should frequently check Tc-MEP after these manoeuvres. This patient had no neurological deficits and was considered to be a rescue case.

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 ( 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.

Background Ossification of the posterior longitudinal ligament of the spine (OPLL) is characterized by heterotopic bone formation in the posterior longitudinal ligament of the spine. Although the patients with OPLL are more common in the 60s and 70s, we know that there are markedly young patients (e.g., early 40s). However, to the best of our knowledge, there is few reports characterize young patients with cervical OPLL in terms of the imaging features, subjective symptoms, and ADL problems. Methods This is the multicenter cross-sectional study. Two hundred and thirty-seven Japanese symptomatic patients with cervical OPLL confirmed by standard X-rays collected from 16 institutions belonging to the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament formed by the Japanese Ministry of Health, Labor and Welfare were recruited. Whole spine CT data as well as demographic data such as age, gender, patients-based evaluations, and the 36-item Short Form Health Survey (SF-36) were evaluated. Results Young group (≦ 45 years old) consisted of 23 patients (8 females and 15 males), accounting for 9.7% of the total. Their characteristics were high body mass index (BMI), significant involvement of trauma in the onset and deterioration of symptoms, and the predominance of thoracic OPLL. The patient-based evaluations did not show a significant difference between the young and non-young groups, or between the genders in the young group except for bodily pain (BP) of SF-36. Female patients in young group had significantly lower BP score of SF-36 than that of male in young group. Conclusions Characteristics of young patients with cervical OPLL were high BMI, significant involvement of trauma in the onset and deterioration of symptoms, lower BP score of SF-36 in female, and the predominance of thoracic OPLL.

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.

Study Design: Retrospective study.Objective: To investigate the long-term clinical outcome and incidence of iliac screw-related complications in patients with adult spinal deformity (ASD).Summary of Background Data: Rigid lumbosacral fixation is crucial to achieve optimal global alignment and successful long-term clinical outcomes.Methods: The data of eligible patients with ASD who underwent spinopelvic fixation using bilateral iliac screws with at least 5-year follow-up periods were retrospectively analyzed. Iliac screw loosening and rod breakage between the S1 and iliac (S1/IL) screws were defined as distal instability (DI). Demographic data, health-related quality of life scores, and spinopelvic parameters in the DI group were compared with those in the non-DI group. Sub-group analyses were performed between the cases with and without alignment change after rod fracture at S1/IL.Results: Of the 159 patients, the data of 110 patients (15 men, 95 women; mean age, 67.8 years) were analyzed. The follow-up rate was 69%. Forty-five (41%) patients showed DI (29 cases [26%] in screw loosening, 16 cases [15%] in rod breakage). Eight patients (7.3%) required revision surgery because of iliac screw-related complications. No significant differences were observed in the Oswestry Disability Index and Scoliosis Research Society questionnaire (revised) scores between the DI and non-DI groups. The patients with iliac screw loosening showed significantly greater values of preoperative pelvic incidence, pelvic tilt (PT) and postoperative PT, and T1-pelvic angle. In patients with rod breakage at S1/IL, five patients (31%) who had associated mechanical complications showed an alignment change between pre and post rod breakage. They showed significantly higher and lower rates of high-grade osteotomies and L5/S interbody fusion, respectively.Conclusion: The incidence rate of iliac screw-related complications was relatively high. However, they had a little effect on sagittal alignment deterioration and there were few cases that required revision surgery., Mini abstract:Long fusion surgery with pelvic fixation using iliac screw resulted in higher incidence rates of iliac screw-related complications; however, the cases that required revision surgery were limited (7.3%). Iliac screw loosening and rod breakage at S1/IL had little effect on sagittal alignment deterioration.

Introduction: Assessments of early postoperative bony union after posterior lumbar interbody fusion via computed tomography (CT) have revealed cases in which interbody fixation by bony union resulted in nonfusion due to bone absorption. The apparent bone union state reverted to a nonunion state several months later, exhibiting a so-called “fake union” phenomenon. Additionally, few reports have evaluated the effect of teriparatide on bony union. The present study aimed to evaluate the frequency of change in assessment from fusion to nonfusion in the postoperative follow-up of lumbar interbody fusion, compare the late postoperative bony union rates in groups with or without early postoperative fusion, and examine the effect of postoperative teriparatide in those groups. Methods: Sixty-nine subjects enrolled from multiple hospitals were prospectively evaluated following single-level lumbar interbody fusion. The patients were randomly allocated into treatment with or without weekly postoperative teriparatide. The subjects were then classified as having bony union or nonfusion at 2 months postoperatively, and fusion rates at 6 months were compared. For the evaluation of bony union, blinded radiological examinations were performed via CT. Additional comparisons were made according to teriparatide use. Results: The rate of nonunion at 6 months postoperatively in patients with fusion at 2 months postoperatively was 27.8%. Among subjects with bony union at 2 months postoperatively, the fusion rate at 6 months in those who received teriparatide was 93.3% (p=0.027) versus 57.1% in those who did not. Conclusions: The rate of nonunion at 6 months postoperatively in patients exhibiting union at 2 months after surgery was 27.8%. Postoperative weekly teriparatide treatment significantly reduced the rate of fake union.

Introduction: Kyphotic deformity is common after spinal tumor resection surgery. An adequate field of view is needed to resect the spinal cord tumor, and, in some cases, the facet joint must be removed during laminectomy, and fixation may be performed simultaneously. In this study, we investigated the incidence of postoperative deformity after spinal tumor resection and the factors associated with postoperative deformity. Methods: We retrospectively analyzed patients who underwent thoracic spinal cord tumor resection at a single institution between 2010 and 2017 and were followed up for at least 24 months after surgery. Fifty percent or more of the facet joint was removed during the laminectomy, and fixation was performed simultaneously. Patients were divided into two groups, with and without kyphotic deformity. Patient demographic characteristics (age at surgery and gender), whether they underwent primary surgery or reoperation, tumor level, pathological type, and surgical method were compared. Multiple linear regression analysis was performed to identify independent predictors of kyphotic deformity. Results: Thirty-one patients were found to be eligible. Thirteen patients had intramedullary spinal cord tumors. Laminectomy was performed in 52% (N=16), laminoplasty in 6% (N=2), and laminectomy and/or laminoplasty combined with fusion in 42% (N=13) of the patients. During a mean follow-up period of 66.8 months, 12 (39%) patients had postoperative kyphosis deformities, of which one patient (3%, a 12-year-old girl who underwent combined postoperative radiation therapy) underwent kyphosis correction surgery three years after surgery. The number of laminectomies was independently associated with kyphotic deformity. Conclusions: Although kyphotic deformity after spinal tumor surgery was observed in about 39% of the patients, corrective surgery was rarely required due to the progression of the deformity. The high number of laminectomies is a risk factor for postoperative kyphosis, and prophylactic fixation may be considered in cases of multiple laminectomies.

Study Design:A prospective studyObjective:To investigate the paravertebral and lower extremity muscle activities using surface electromyography (S-EMG) in patients with adult spinal deformity (ASD) comparing with those of age-matched controls.Summary of Background Data:Although the paravertebral muscle is greatly involved in ASD pathology, little is known about the contribution of lower extremity muscle on maintaining standing posture.Methods:Fourteen patients with ASD (1 man, 13 women; mean age, 67.1 years) who underwent corrective fusion surgery with at least 2 years of follow-up and age-matched controls (1 men, 7 women; mean age, 69.3 years) were enrolled. The muscle activities of the thoracic and lumbar erector spinae (TES and LES), external oblique (EO), gluteus maximus (GM), rectus femoris (RF), and biceps femoris (BF) were recorded in the upright and anterior flexion positions using S-EMG pre-operatively and 1 year post-operatively.Results:Compared with controls, patients showed a significantly higher muscle activity in the LES and BF at rest in a standing position. After corrective fusion surgery, the muscle activity of LES decreased and that of RF increased (p

Purpose. Ligamentum flavum hypertrophy (HLF) is the most important component of lumbar spinal canal stenosis (LSCS). Analysis of hypertrophied ligamentum flavum (HLF) samples from patients with LSCS can be an important que. The current study analyzed the surgical samples of HLF samples in patients with LCSC using quantitative and qualitative high performance-liquid chromatography and mass spectrometry.Methods. We collected ligamentum flavum (LF) tissue from twelve patients with LSCS and from four patients with lumbar disk herniation (LDH). We defined LF from LSCS patients as HLF and that from LDH patients as non-hypertrophied ligamentum flavum (NHLF). Total lipids were extracted from the LF samples and evaluated for quantity and quality using liquid chromatography and mass spectrometry.Results. The total lipid amount of the HLF group was 3.6 times higher than that of the NHLF group. Phosphatidylcholines (PCs), ceramides (Cers), O-acyl-ω-hydroxy fatty acids (OAHFAs), and triglycerides (TGs) in the HLF group were more than 32 times higher than those of the NHLF group. PC(26:0)+H+, PC(25:0)+H+, and PC(23:0)+H+ increased in all patients in the HLF group compared to the NHLF group. The thickness of the LF correlated significantly with PC(26:0)+H+ in HLF. Conclusion. We identified the enriched specific PCs, Cers, OAHFAs, and TGs in HLF.

Study design A prospective, multicenter study. Objective To evaluate the usefulness of transcranial motor-evoked potentials (Tc-MEPs) during supine-to-prone position change for thoracic ossification of the posterior longitudinal ligament (T-OPLL). Summary of background data Supine-to-prone position change might be a risk of spinal cord injury in posterior decompression and fusion surgeries for T-OPLL. Methods The subjects were 145 patients with T-OPLL surgically treated with posterior decompression and fusion using Tc-MEPs in 14 institutes. Tc-MEPs were monitored before surgery from supine-to-prone position and intraoperatively in 7 institutes and only intraoperatively in the other 7 institutes because of disapproval of the anesthesia department. In cases of Tc-MEP alert after position change, we adjusted the cervicothoracic posture. When the MEP did not recover, we reverted the position to supine and monitored the Tc-MEPs in supine position. Results There were 83 and 62 patients with/without Tc-MEP before position change to prone (group A and B). The true-positive rate was lower in group A than group B, but without statistical significance (8.4% vs 16.1%, p = 0.12). In group A, 5 patients who had Tc-MEP alert during supine-to-prone position change were all female and had larger body mass index values and upper thoracic lesions. Among the patients, 3 underwent surgeries after cervicothoracic alignment adjustment, and 2 had postponed operations to 1 week later with halo-vest fixation because of repeated Tc-MEP alerts during position change to prone. The Tc-MEP alert at exposure was statistically more frequent in group B than in group A (p = 0.033). Conclusion Tc-MEP alert during position change is an important sign of spinal cord injury due to alignment change at the upper thoracic spine. Tc-MEP monitoring before supine-to-prone position change was necessary to prevent spinal cord injury in surgeries for T-OPLL.Level of Evidence: 4.

OBJECTIVE Achievement of minimal clinically important differences (MCIDs) in the Scoliosis Research Society–22r (SRS-22r) subdomains represents surgical efficacy. However, whether achievements of MCIDs in SRS-22r domains are associated with long-term satisfaction in patients with adult spinal deformity (ASD) is unclear. This study aimed to elucidate factors affecting patient satisfaction after thoracopelvic corrective fusion surgery in patients with ASD. METHODS Data obtained in 187 patients with ASD who underwent extensive corrective fusion surgery from the thoracic spine to the pelvis between 2010 and 2017 and underwent follow-up for 2 years were retrospectively reviewed. The authors investigated the likelihood of achieving MCIDs in the function, pain, self-image, mental health, and subtotal domains 2 years after surgery. The following MCID values were used: function, 0.90; pain, 0.85; self-image, 1.05; mental health, 0.70; and subtotal, 1.05. Multivariate analysis was performed to evaluate factors associated with patient satisfaction 2 years after surgery. RESULTS The average satisfaction scores in the group that achieved MCID and the group that did not were as follows: 3.97 and 3.37 for function (p < 0.001), 3.66 and 3.51 for pain (p = 0.221), 3.84 and 3.06 for self-image (p < 0.001), 3.82 and 3.28 for mental health (p < 0.001), and 3.96 and 3.30 for subtotal (p < 0.001), respectively. Except for the pain domain, the group that achieved MCIDs showed greater satisfaction than the group that did not achieve MCIDs. On multivariate analysis, factors related to postoperative satisfaction were achievement of SRS-22r self-image (standardization coefficient 0.322, p < 0.001) and function (standardization coefficient 0.179, p = 0.026) MCIDs. Perioperative complications and revision surgery were not related to patient satisfaction. CONCLUSIONS Multivariate analysis demonstrated that achievement of MCIDs in SRS-22r self-image and function domains was significantly associated with postoperative satisfaction. Given that patients with poor preoperative health-related quality of life are more likely to achieve MCIDs in SRS-22r domains, surgeons should carefully consider whether to operate on patients with relatively good baseline health-related quality of life when making surgical decisions.

STUDY DESIGN A prospective nutritional intervention study for adult spinal deformity (ASD) patients. OBJECTIVE To investigate how a nutritional intervention affects the incidence of postoperative medical complications and the nutritional status. SUMMARY OF BACKGROUND DATA The medical complication rate in ASD surgery is very high, and one risk factor is malnutrition. Nutritional intervention may improve the patient's nutritional status and reduce risk, but this is unexplored regarding ASD surgery. METHODS Malnourished patients (i.e., a Prognostic Nutritional Index (PNI) score of

Intraoperative neuromonitoring (IONM) is important for detecting neurological dysfunction, allowing for intervention and reversal of neurological deficits before they become permanent. Of the several IONM modalities, transcranial electrical stimulation of motor-evoked potential (TES-MEP) can help monitor the activity in the pyramidal tract. Surgery- and non-surgery-related factors could result in a TES-MEP alert during surgery. Once the alert occurs, the surgeon should immediately intervene to prevent a neurological complication. However, TES-MEP monitoring does not provide sufficient data to identify the non-surgery-related factors. Therefore, this study aimed to identify and describe these factors among TES-MEP alert cases.In this multicenter study, data from 1934 patients who underwent various spinal surgeries for spinal deformities, spinal cord tumors, and ossification of the posterior longitudinal ligament of the spine from 2017 to 2019 were collected. A 70% amplitude reduction was set as the TES-MEP alarm threshold. All surgeries with alerts were categorized into true-positive (TP) and false-positive (FP) cases according to the assessment of immediate postoperative neurological deficits.In total, TES-MEP alerts were observed in 251 cases during surgery: 62 TP and 189 FP IONM cases. Overall, 158 cases were related to non-surgery-related factors. We observed 22 (35.5%) TP cases and 136 (72%) FP cases, which indicated cases associated with non-surgery-related factors. A significant difference was observed between the two groups regarding factors associated with TES-MEP alerts (p 0.01). The ratio of TP and FP cases (related to non-surgery-related factors) associated with TES-MEP alerts was 13.9% (22/158 cases) and 86.1% (136/158 cases), respectively.Non-surgery-related factors are proportionally higher in FP than in TP cases. Although the surgeon should examine surgical procedures immediately after a TES-MEP alert, surgical intervention may not always be the best approach according to the results of this study.

Adult spinal deformity; Patient reported outcomes; Spinal deformity surgery Deformidad espinal en el adulto; Resultados informados por el paciente; Cirugía de deformidad espinal Deformitat espinal de l'adult; Resultats informats pel pacient; Cirurgia de deformitat espinal Study Design: Prospective cohort. Objective: To prospectively evaluate PROs up to 5-years after complex ASD surgery. Methods: The Scoli-RISK-1 study enrolled 272 ASD patients undergoing surgery from 15 centers. Inclusion criteria was Cobb angle of >80°, corrective osteotomy for congenital or revision deformity, and/or 3-column osteotomy. The following PROs were measured prospectively at intervals up to 5-years postoperative: ODI, SF36-PCS/MCS, SRS-22, NRS back/leg. Among patients with 5-year follow-up, comparisons were made from both baseline and 2-years postoperative to 5-years postoperative. PROs were analyzed using mixed models for repeated measures. Results: Seventy-seven patients (28.3%) had 5-year follow-up data. Comparing baseline to 5-year data among these 77 patients, significant improvement was seen in all PROs: ODI (45.2 vs. 29.3, P < 0.001), SF36-PCS (31.5 vs. 38.8, P < 0.001), SF36-MCS (44.9 vs. 49.1, P = 0.009), SRS-22-total (2.78 vs. 3.61, P < 0.001), NRS-back pain (5.70 vs. 2.95, P < 0.001) and NRS leg pain (3.64 vs. 2.62, P = 0.017). In the 2 to 5-year follow-up period, no significant changes were seen in any PROs. The percentage of patients achieving MCID from baseline to 5-years were: ODI (62.0%) and the SRS-22r domains of function (70.4%), pain (63.0%), mental health (37.5%), self-image (60.3%), and total (60.3%). Surprisingly, mean values (P > 0.05) and proportion achieving MCID did not differ significantly in patients with major surgery-related complications compared to those without. Conclusions: After complex ASD surgery, significant improvement in PROs were seen at 5-years postoperative in ODI, SF36-PCS/MCS, SRS-22r, and NRS-back/leg pain. No significant changes in PROs occurred during the 2 to 5-year postoperative period. Those with major surgery-related complications had similar PROs and proportion of patients achieving MCID as those without these complications. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was funded by AO Spine through the AO Spine Knowledge Forum Deformity, the Scoliosis Research Society (SRS), and Norton Healthcare. AO Spine Knowledge Forum Deformity is a focused group of international deformity experts. AO Spine is a clinical division of the AO Foundation, which is an independent medically-guided not-for-profit organization. Study support was provided directly through the AO Spine Research Department and the AO Innovation Translation Center, Clinical Evidence.

Study DesignCombination of retrospective and prospective study.PurposeWe aimed to compare the clinical outcomes between local fixation surgery and spinopelvic fixation surgery for the treatment of kyphosis secondary to osteoporotic vertebral fractures with spinopelvic malalignment.Overview of LiteratureThe clinical characteristics of patients with rigid kyphosis due to osteoporotic vertebral fracture differ from that of middle-aged patients with vertebral fractures in terms of bone fragility and presence of spinopelvic malalignment. Little is known about the surgical strategies for these deformities, most especially the extent of fusion of vertebra involved.MethodsWe analyzed 24 patients with vertebral osteotomy at the level of the fracture and spinal fixation without pelvic fixation (local group), and 22 patients with vertebral osteotomy and pelvic fixation (pelvic group). Radiographic parameters, the incidence of proximal junctional kyphosis (PJK), distal junctional kyphosis (DJK), rod fractures, and the Oswestry Disability Index (ODI) were compared between the two groups over a 2-year follow-up period.ResultsIn the pelvic group, postoperative spinopelvic parameters significantly improved, with the improvements maintained. No remarkable changes in spinopelvic parameters were seen in the local group. The mean ODI scores 2 years after surgery were 45.3 and 33.0 in the local and pelvic group, respectively (p-value

Introduction: Chronic low back pain (CLBP) is a leading cause of disability, yet there is limited high-quality evidence to identify the most suitable pharmacological therapy. The purpose of this Japanese nationwide, multicenter, prospective study was to compare the effectiveness of four representative drug therapies―acetaminophen, celecoxib, loxoprofen, and a tramadol and acetaminophen (T+A) combination drug―to establish evidence for a drug of choice for CLBP. Methods: Patients with CLBP (N=471) received one of the four treatments and were evaluated, prospectively and comprehensively, once every month for six months using a visual analog scale (VAS) for LBP, the Japanese Orthopedic Association (JOA) score, the JOA Back Pain Evaluation Questionnaire (JOABPEQ), the Roland-Morris Disability Questionnaire (RDQ), the EuroQol five-dimensions three-levels (EQ-5D-3L), and the Short Form-8 item health survey (SF-8). We conducted multivariable linear regression analyses of the four drugs at 1 and 6 months after drug allocation. Differences with P

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.

Study design A prospective multicenter observational study. Objective To elucidate the efficacy of transcranial motor-evoked potentials (Tc(E)-MEPs) in degenerative cervical myelopathy (DCM) surgery by comparing cervical spondylotic myelopathy (CSM) to cervical ossification of the posterior longitudinal ligament (OPLL) and investigate the timing of Tc(E)-MEPs alerts and types of interventions affecting surgical outcomes. Summary of background data Although CSM and OPLL are the most commonly encountered diseases of DCM, the benefits of Tc(E)-MEPs for DCM remain unclear and comparisons of these two diseases have not yet been conducted. Methods We examined the results of Tc(E)-MEPs from 1176 DCM cases (840 CSM /336 OPLL) and compared patients background by disease, preoperative motor deficits, and the type of surgical procedure. We also assessed the efficacy of interventions based on Tc(E)-MEPs alerts. Tc(E)-MEPs alerts were defined as an amplitude reduction of more than 70% below the control waveform. Rescue cases were defined as those in which waveform recovery was achieved after interventions in response to alerts and no postoperative paralysis. Results Overall sensitivity was 57.1%, and sensitivity was higher with OPLL (71.4%) than with CSM (42.9%). The sensitivity of acute onset segmental palsy including C5 palsy was 40% (OPLL/CSM: 66.7%/0%) whereas that of lower limb palsy was 100%. The most common timing of Tc(E)-MEPs alerts was during decompression (63.16%), followed by screw insertion (15.79%). The overall rescue rate was 57.9% (OPLL/CSM: 58.3%/57.1%). Conclusion Since Tc(E)-MEPs are excellent for detecting long tract injuries, surgeons need to consider appropriate interventions in response to alerts. The detection of acute onset segmental palsy by Tc(E)-MEPs was partially possible with OPLL, but may still be difficult with CSM. The rescue rate was higher than 50% and appropriate interventions may have prevented postoperative neurological complications.Level of Evidence: 3.

OBJECTIVE Extensive corrective fusion surgery was performed on elderly patients with adult spinal deformity (ASD) to improve abnormal posture. Varying improvements in postoperative walking function were expected owing to differences in muscular strength and bone quality between patients in their 40s and those over 75 years of age. The purpose of this study was to compare preoperative and postoperative gait posture and physical functionality in elderly patients with ASD who underwent extensive corrective fusion to the thoracic spine. METHODS A prospectively maintained surgical database was reviewed for patients with ASD who underwent corrective fusion surgery (thoracic spine to pelvis) between 2011 and 2016. The cohort was divided into three age groups: nonelderly (40–64 years), young-old (65–74 years), and old-old (> 75 years). Patients underwent a 4-m walk test preoperatively and 2 years postoperatively to measure gait-trunk tilt angle and walking speed (meters per minute). RESULTS Among 291 patients with ASD who underwent corrective fusion surgery, 56 patients (14 men and 42 women; mean age 68.8 years) were included. Mean preoperative gait-trunk tilt angle (12.9° vs 5.2°, p < 0.01) and walking speed (41.2 m/min vs 45.7 m/min, p < 0.01) significantly improved postoperatively. Intergroup analysis revealed that the mean preoperative gait-trunk tilt angles in the nonelderly (n = 13), young-old (n = 28), and old-old (n = 15) groups were 11.9°, 10.0°, and 19.3°, respectively; postoperatively, these improved to 4.5°, 4.5°, and 7.2°, respectively. Mean preoperative walking speeds of 47.9, 40.0, and 37.7 m/min improved to 52.4, 44.8, and 41.5 m/min postoperatively in the nonelderly, young-old, and old-old groups, respectively. There were no statistically significant differences in degree of improvement in gait-trunk tilt angle and walking speed among groups. CONCLUSIONS Extensive corrective fusion surgery improved the postoperative walking posture of patients with ASD. Statistical analysis of gait measurements demonstrated intergroup equivalence, indicating comparable improvement in physical functionality in elderly and middle-aged patients after corrective fusion surgery.

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.

Study Design: Multicenter prospective study. Objectives: Although intramedullary spinal cord tumor (IMSCT) and extramedullary SCT (EMSCT) surgeries carry high risk of intraoperative motor deficits (MDs), the benefits of transcranial motor evoked potential (TcMEP) monitoring are well-accepted; however, comparisons have not yet been conducted. This study aimed to clarify the efficacy of TcMEP monitoring during IMSCT and EMSCT resection surgeries. Methods: We prospectively reviewed TcMEP monitoring data of 81 consecutive IMSCT and 347 EMSCT patients. We compared the efficacy of interventions based on TcMEP alerts in the IMSCT and EMSCT groups. We defined our alert point as a TcMEP amplitude reduction of ≥70% from baseline. Results: In the IMSCT group, TcMEP monitoring revealed 20 true-positive (25%), 8 rescue (10%; rescue rate 29%), 10 false-positive, a false-negative, and 41 true-negative patients, resulting in a sensitivity of 95% and a specificity of 80%. In the EMSCT group, TcMEP monitoring revealed 20 true-positive (6%), 24 rescue (7%; rescue rate 55%), 29 false-positive, 2 false-negative, and 263 true-negative patients, resulting in a sensitivity of 91% and specificity of 90%. The most common TcMEP alert timing was during tumor resection (96% vs. 91%), and suspension surgeries with or without intravenous steroid administration were performed as intervention techniques. Conclusions: Postoperative MD rates in IMSCT and EMSCT surgeries using TcMEP monitoring were 25% and 6%, and rescue rates were 29% and 55%. We believe that the usage of TcMEP monitoring and appropriate intervention techniques during SCT surgeries might have predicted and prevented the occurrence of intraoperative MDs.

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%.

STUDY DESIGN Prospective multicenter study. OBJECTIVE To examine transcranial motor evoked potential (Tc-MEP) waveforms in intraoperative neurophysiological monitoring (IONM) in surgery for intradural extramedullary (IDEM) tumors, focused on the characteristics for cervical, thoracic and conus lesions. SUMMARY OF BACKGROUND DATA IDEM tumors are normally curable after resection, but neurological deterioration may occur after surgery. IONM using Tc-MEPs during surgery is important for timely detection of possible neurological injury. METHODS The subjects were 233 patients with IDEM tumors treated surgically with Tc-MEP monitoring at 9 centers. The alarm threshold was ≥70% waveform deterioration from baseline. A case with a Tc-MEP alert that normalized and had no new motor deficits postoperatively was defined as a rescue case. A deterioration of manual muscle test (MMT) score ≥1 compared to the preoperative value was defined as postoperative worsening of motor status. RESULTS The 233 patients (92 males, 39%) had a mean age of 58.1 ± 18.1 years, and 185 (79%), 46 (20%) and 2 (1%) had schwannoma, meningioma, and neurofibroma. These lesions had cervical (C1-7), thoracic (Th1-10), and conus (Th11-L2) locations in 82 (35%), 96 (41%) and 55 (24%) cases. There were no significant differences in preoperative motor deficit among the lesion levels. Thoracic lesions had a significantly higher rate of poor baseline waveform derivation (0% cervical, 6% thoracic, 0% conus, p

STUDY DESIGN Prospective multicenter study. OBJECTIVE The purpose of the study is to examine cases with poor baseline waveform derivation for all muscles in multichannel monitoring of transcranial motor-evoked potentials (Tc-MEPs) in spine surgery. SUMMARY OF BACKGROUND DATA Intraoperative neuromonitoring (IONM) is useful for identifying neurologic deterioration during spinal surgery. Tc-MEPs are widely used for IONM, but some cases have poor waveform derivation, even in multichannel Tc-MEP monitoring. METHODS The subjects were 3625 patients (mean age 60.1 years, range 4-95; 1886 females, 1739 males) who underwent Tc-MEP monitoring during spinal surgery at 16 spine centers between April 2017 and March 2020. Baseline Tc-MEPs were recorded from the deltoid, abductor pollicis brevis, adductor longus, quadriceps femoris, hamstrings, tibialis anterior, gastrocnemius, and abductor hallucis (AH) muscles after surgical exposure of the spine. RESULTS The 3625 cases included cervical, thoracic, and lumbar lesions (50%, 33% and 17%, respectively) and had preoperative motor status of no motor deficit, and motor deficit with manual muscle testing (MMT) ≥3 and MMT

Aim The 25-question Geriatric Locomotive Function Scale (hereafter, "GLFS-25") is a simple screening tool to detect elderly individuals at high risk of locomotive syndrome and promote interventions. This cohort study aimed to clarify if it can predict the need for nursing care certification in the near future. Methods Participants were 531 Japanese adults aged ≥65 years who had undergone a healthcare checkup in 2012 and never received nursing care certification until 2012. We collected baseline information and conducted a physical examination in 2012. We investigated the presence of nursing care certification and care need level from 2013 to 2018. Relationships of these factors with nursing care certification after 6 years were assessed. A receiver operating characteristic curve for both the GLFS-25 and physical examination were used to determine optimal threshold value. Results From 2013 to 2018, 114 volunteers (21.4%) applied for nursing care certification and 29 volunteers died. The group with nursing care certification (over support level 1) had an average age of 79.9 years and a mean score of 17.8 on the scale. Those without nursing care certification had an average age of 74.1 years and a mean score of 8.7. When the GLFS-25 score was 12.5, sensitivity was 0.658 and specificity was 0.760. The area under the curve was 0.736 (95% confidence interval 0.682-0.789). Conclusions The GLFS-25 has enabled early detection of individuals with locomotive syndrome who are more likely to need nursing care certification in the near future. We propose using a cutoff score of 13 for the scale. Geriatr Gerontol Int ••; ••: ••-•• Geriatr Gerontol Int 2021; ••: ••-••.

Mini abstractWe summarized the cost-effectiveness of surgical treatment for adult spinal deformity by operative method over 2 years post-surgery. Cost/ QALY 2 years after surgery was USD 492,276 on average (USD 509,370 for the multiple Grade-2 osteotomy, USD 518,406 for the 3-column osteotomy, and USD 463,798 for the LLIF group)., Structured abstractStudy design: Retrospective cohort study.Objective: To summarize the cost-effectiveness of surgical treatment for adult spinal deformity (ASD) according to the operative method over 2 years postoperatively.Summary of background data: Extensive corrective fusion surgery for ASD requires numerous expensive implants, greatly contributing toward the national medical expenses. Previous national studies reported high complication rates in spinal surgeries using instrumentation. However, the cost-effectiveness of such procedures has not been scrutinized.Methods: In total, 173 ASD patients (151 women; mean age 69.1 years) who underwent corrective fusion between 2010 and 2017 were included. Cost-effectiveness was evaluated according to the cost of obtaining 1 quality-adjusted life year (QALY). Patients were divided into three groups, the “corrective fusion surgery using multiple Grade 2 osteotomy” (Grade-2) group, 3-column osteotomy group (3-column), and lateral lumbar interbody fusion (LLIF) group.Results: The average medical cost for the initial surgery was USD 72,240, and that during the 2 years after the initial surgery was USD 76,294. The medical expenses for the initial surgery and those over the 2 years were higher in the LLIF group. The cumulative improvement in QALY over the 2 years did not significantly differ among the groups (0.13, 0.15, and 0.18 in the Grade-2, 3-column, and LLIF groups, respectively). Cost/QALY 2 years after the surgery was USD 509,370, 518,406, and 463,798 in the Grade-2, 3-column, and LLIF groups, respectively.Conclusion: We summarized the medical costs and cost-effectiveness of three different surgical methods for ASD in patients with different backgrounds over 2 years postoperatively. The medical expense for the initial surgery was highest in the LLIF group, and the cumulative improvement in QALY over the 2 years tended to be higher in the LLIF group, but the difference was not significant; the overall cost-effectiveness was lowest in the LLIF group.

OBJECTIVENonunion after posterior lumbar interbody fusion (PLIF) is associated with poor long-term outcomes in terms of health-related quality of life. Biomechanical factors in the fusion segment may influence spinal fusion rates. There are no reports on the relationship between intervertebral union and the absorption of autografts or vertebral endplates. Therefore, the purpose of this retrospective study was to evaluate the risk factors of nonunion after PLIF and identify preventive measures.METHODSThe authors analyzed 138 patients who underwent 1-level PLIF between 2016 and 2018 (75 males, 63 females; mean age 67 years; minimum follow-up period 12 months). Lumbar CT images obtained soon after the surgery and at 6 and 12 months of follow-up were examined for the mean total occupancy rate of the autograft, presence of a translucent zone between the autograft and endplate (more than 50% of vertebral diameter), cage subsidence, and screw loosening. Complete intervertebral union was defined as the presence of both upper and lower complete fusion in the center cage regions on coronal and sagittal CT slices at 12 months postoperatively. Patients were classified into either union or nonunion groups.RESULTSComplete union after PLIF was observed in 62 patients (45%), while nonunion was observed in 76 patients (55%). The mean total occupancy rate of the autograft immediately after the surgery was higher in the union group than in the nonunion group (59% vs 53%; p = 0.046). At 12 months postoperatively, the total occupancy rate of the autograft had decreased by 5.4% in the union group and by 11.9% in the nonunion group (p = 0.020). A translucent zone between the autograft and endplate immediately after the surgery was observed in 14 and 38 patients (23% and 50%) in the union and nonunion groups, respectively (p = 0.001). The nonunion group had a significantly higher proportion of cases with cage subsidence and screw loosening at 12 months postoperatively in comparison to the union group (p = 0.010 and p = 0.009, respectively).CONCLUSIONSA lower occupancy rate of the autograft and the presence of a translucent zone between the autograft and endplate immediately after the surgery were associated with nonunion at 12 months after PLIF. It may be important to achieve sufficient contact between the autograft and endplate intraoperatively for osseous union enhancement and to avoid excessive absorption of the autograft. The achievement of complete intervertebral union may decrease the incidence of cage subsidence or screw loosening.

Solitary fibrous tumors are rare mesenchymal neoplasms with highly recurrence rates after intratumor resection. We report 2 cases of solitary fibrous tumors treated with combination therapy with embolization and en bloc laminectomy using thread saw. To the best of our knowledge, this is the first such report. In the 2 cases, the hypervascular tumors were located in the spinal process and infiltrating the multifidus. Preoperative embolization was useful for decreasing intraoperative bleeding, and using thread saw was an ideal technique for deciding the cut surface height of the pedicle to achieve gross total resection.

This is the first report using intraoperative CT navigation for Tumor-induced Osteomalacia (TIO) lesions of the spine. TIO is a rare paraneoplastic disorder caused by tumors secret Fibroblast growth factor 23 secreted by tumor tissue. Surgical resection of the main tumor is the only definitive treatment. However, the tumor is usually small, and it hard to find it, and it tends to be seen when the recurrence is caused by the difficulty of whole tumor resection. A 57-year-old woman presented with a rare case of TIO located in T10 vertebra body. Using the intraoperative CT navigation, we resected the tumor in the T10 vertebral body very effective for accurate localization of the tumor and helpful for guidance of resection area and confirmation for excision of tumor. As a treatment for TIO, we report a tumor resection with intraoperative computed tomography navigation that made it possible to resect tumor in T10 vertebrae precisely and safely, which is small and difficult and dangerous access.

Study design Prospective, multicenter, observational study. Objective The aim of this study was to investigate the efficacy of intervention after an alert in intraoperative neurophysiological monitoring (IONM) using transcranial motor-evoked potentials (Tc-MEPs) during surgery for thoracic ossification of the posterior longitudinal ligament (T-OPLL). Summary of background data T-OPLL is commonly treated with posterior decompression and fusion with instrumentation. IONM using Tc-MEPs during surgery reduces the risk of neurological complications. Methods The subjects were 79 patients with a Tc-MEP alert during posterior decompression and fusion surgery for T-OPLL. Preoperative muscle strength (manual muscle testing [MMT]), waveform derivation rate at the start of surgery (baseline), intraoperative waveform changes; and postoperative motor paralysis were examined. A reduction in MMT score of ≥1 on the day after surgery was classified as worsened postoperative motor deficit. An alert was defined as a decrease in Tc-MEP waveform amplitude of ≥70% from baseline. Alerts were recorded at key times during surgery. Results The patients (35 males, 44 females; age 54.6 years) had OPLL at T1-4 (n = 27, 34%), T5-8 (n = 50, 63%), and T9-12 (n = 16, 20%). The preoperative status included sensory deficit (n = 67, 85%), motor deficit (MMT ≤4) (n = 59, 75%), and nonambulatory (n = 26, 33%). At baseline, 76 cases (96%) had a detectable Tc-MEP waveform for at least one muscle, and the abductor hallucis had the highest rate of baseline waveform detection (n = 66, 84%). Tc-MEP alerts occurred during decompression (n = 47, 60%), exposure (n = 13, 16%), rodding (n = 5, 6%), pedicle screw insertion (n = 4, 5%), posture change (n = 4, 5%), dekyphosis (n = 2, 3%), and other procedures (n = 4, 5%). After intraoperative intervention, the rescue rate (no postoperative neurological deficit) was 57% (45/79), and rescue cases had a significantly better preoperative ambulatory status and a significantly higher baseline waveform derivation rate. Conclusion These results show the efficacy of intraoperative intervention following a Tc-MEP alert for prevention of neurological deficit postoperatively.Level of Evidence: 2.

Background The Global Alignment and Proportion (GAP) score, based on pelvic incidence-based proportional parameters, was recently developed to predict mechanical complications after surgery for spinal deformities in adults. However, this score has not been validated in an independent external dataset. Questions/purposes After adult spinal deformity surgery, is a higher GAP score associated with (1) an increased risk of mechanical complications, defined as rod fractures, implant-related complications, proximal or distal junctional kyphosis or failure; (2) a higher likelihood of undergoing revision surgery to treat a mechanical complication; and (3) is a lower (more proportioned) GAP score category associated with better validated outcomes scores using the Oswestry Disability Index (ODI), Scoliosis Research Society-22 (SRS-22) and the Short Form-36 questionnaires? Methods A total of 272 patients who had undergone corrective surgeries for complex spinal deformities were enrolled in the Scoli-RISK-1 prospective trial. Patients were included in this secondary analysis if they fulfilled the original inclusion criteria by Yilgor et al. From the original 272 patients, 14% (39) did not satisfy the radiographic inclusion criteria, the GAP score could not be calculated in 14% (37), and 24% (64) did not have radiographic assessment at postoperative 2 years, leaving 59% (159) for analysis in this review of data from the original trial. The GAP score was calculated using parameters from early postoperative radiographs (between 3 and 12 weeks) including pelvic incidence, sacral slope, lumbar lordosis, lower arc lordosis and global tilt, which were independently obtained from a computer software based on centralized patient radiographs. The GAP score was categorized as proportional (scores of 0 to 2), moderately disproportional (scores of 3 to 6), or severely disproportional (scores higher than 7 to 13). Receiver operating characteristic area under curve (AUC) was used to assess associations between GAP score and risk of mechanical complications and risk of revision surgery. An AUC of 0.5 to 0.7 was classified as "no or low associative power", 0.7 to 0.9 as "moderate" and greater than 0.9 as "high". We analyzed differences in validated outcome scores between the GAP categories using Wilcoxon rank sum test. Results A total of 159 patients were included in this study, with a mean age of 58 ± 14 years at the time of surgery. Most patients were female (72%, 115 of 159), the mean number of levels involved in surgery was 12 ± 4, and three-column osteotomy was performed in 76% (120 of 159) of patients. At a minimum of 2 years' follow-up, a higher GAP score was not associated with increased risks of mechanical complications (AUC = 0.60 [95% CI 0.50 to 0.70]). A higher GAP score was not associated with a higher likelihood of undergoing a revision surgery to treat a mechanical complication (AUC = 0.66 [95% 0.53 to 0.78]). However, a moderately disproportioned GAP score category was associated with better SF-36 physical component summary score (36 ± 10 versus 40 ± 11; p = 0.047), better SF-36 mental component summary score (46 ± 13 versus 51 ± 12; p = 0.01), better SRS-22 total score (3.4 ± 0.8 versus 3.7 ± 0.7, p = 0.02) and better ODI score (35 ± 21 versus 25 ± 20; p = 0.003) than severely disproportioned GAP score category. Conclusions Based on the findings of this external validation study, we found that alignment targets based on the GAP score alone were not associated with increased risks of mechanical complications and mechanical revisions in patients with complex adult spinal disorders. Parameters not included in the original GAP score needed to be considered to reduce the likelihood of mechanical complications. Level of evidence Level III, diagnostic study.

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. 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. Postoperatively, 43 patients (3.9%) experienced SSI. Univariate analysis showed that preoperative PNI (48.5 vs 51.7; p

Objective:To measure the medial opening gap and examine a technique for preserving the tibial posterior slope (TPS) in open wedge high tibial osteotomy (OWHTO) using computer-simulated three-dimensional (3D) surgery.Materials and Methods:This study included 24 symptomatic knees from 20 patients (7 men and 13 women; mean age, 67.9 years; range 54–89 years). Digital imaging and communications from computed tomography examination were applied to a 3D picture software program, and several anatomical landmarks were registered. Then, computer simulation of OWHTO as a virtual surgery was performed: the correction angle was decided to make the femorotibial angle 170° and the TPS did not differ between pre- and post-planification. The distance between the proximal and distal cortices of the medial tibia was measured at three points, which were the anterior (AD), posterior (PD), and longest (LD) distance sites in the sagittal plane, using the 3D view, and the ratios of AD/PD and AD/LD were measured. The anteromedial opening gap was compared to the posteromedial gap and the longest distance gap at the osteotomy site. Spearman’s rank correlation coefficient test was used in statistical analysis.Results:Mean AD/PD was 0.740±0.051 (range 0.651–0.850), and mean AD/LD was 0.652±0.040 (range 0.571–0.768). The correction angle was not associated with the values of both AD/PD and AD/LD.Conclusions:The difference in both AD/PD and AD/LD between each patient was regarded as a significant variation. Therefore, preoperative planification with 3D computer simulation to measure AD/PD and AD/LD may be helpful to avoid a significant increase in TPS.

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 6 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 (TK), T1 slope (TS), cervical lordosis (CL), 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

Background Ossification of the posterior longitudinal ligament of the spine (OPLL) is characterized by heterotopic bone formation in the posterior longitudinal ligament of the spine. We know that the size and distribution of the ossified lesions in patients with OPLL are different in each case. However, the characteristics of the patients with radiologically severe cervical OPLL remain unknown. Methods The participants of our study were symptomatic patients with cervical OPLL who were diagnosed by standard radiographs of the cervical spine. Whole-spine CT data and demographic data such as age and sex were obtained from 20 institutions belonging to the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament. According to the number of the levels involved by OPLL, we stratified the patients into two subgroups: severe group (S-group) and non-severe group (NS-group) to delineate the characteristics of radiologically severe patients with cervical OPLL. We also evaluated the most compressed level and the degree of occupying ratio of cervical spinal canal by OPLL at the most compressed level. Results A total of 234 patients with a mean age of 65 years were recruited. The S-group consisted of 48 patients (21%, 12 females and 36 males) and the NS-group consisted of 92 patients (79%, 22 females and 70 males). The mean age of males in the S-group (68 years old) was significantly higher than that of males in the NS-group (64 years old); however there was no significant difference in the mean age in females between the S-group (69 years old) and the NS-group (66 years old). No significant difference of body mass index, ossification of the nuchal ligament-positivity and presence of diabetes mellitus were found between the S- and the NS-group. Conclusions It is likely that the manner of extension of cervical OPLL is different between male and female patients.

Background Since 1929, only 171 epidural hemangioma cases have been reported. We report five epidural hemangiomas and review cases reported over the past decade in terms of radiological features and clinical findings. Methods Among patients operated on for spinal tumors at our hospital between 2009 and 2020, five had epidural hemangiomas. We retrospectively examined patient records and images and reviewed relevant English literature in PubMed from 2009 to 2019. Eighty-seven epidural hemangioma cases were reported in the last 10 years. Results Among 87 cases, the average age was 49.58 years; 43 and 44 cases were male and female, respectively. The most common lesion level was thoracic (59.8%), while common symptoms were back pain (42.5%); numbness, hypoesthesia, or anesthesia (37.9%); paraparesis (34.5%); and radicular pain (20.7%). On magnetic resonance imaging (MRI), 77.1% showed hypo-isointensity on T1-weighted image (WI), hyperintensity on T2WI, and homogenous enhanced patterns with contrast. Total resection was performed in most cases, with good clinical outcomes. Preoperative embolization was performed in four cases, with good surgical outcomes. The median follow-up duration of postoperative MRI was 16 months, and no case had recurrence. Conclusions Epidural hemangiomas are extremely rare and may be difficult to diagnose preoperatively. They should be considered if a dumbbell-shaped or epidural hypervascular lesion is noted. The treatment of choice for epidural hemangioma is total resection, with most cases having good clinical outcomes. Preoperative embolization may be useful for reducing bleeding. Although there were almost no recurrences after resection, careful follow-up for longer periods is required.

OBJECTIVEMany complications are likely to occur in patients with malnutrition. The prognostic nutritional index (PNI) is often used when evaluating a patient’s nutritional condition. However, no studies have investigated the association between nutritional status and postoperative medical complications or prognosis by using the PNI in the field of spinal surgery. The purpose of this retrospective study was to investigate postoperative medical complications and prognoses of patients who had undergone adult spinal deformity (ASD) surgery, according to their preoperative nutritional status.METHODSAll patients aged ≥ 40 years who had undergone scheduled ASD surgery in the authors’ hospital between March 2010 and June 2017 were eligible for study inclusion and were divided into groups according to their PNI (< 50, group L; ≥ 50, group H). Medical complications diagnosed within 30 days postoperatively were evaluated; however, surgical site infection and death were evaluated until 1 and 5 years after surgery, respectively.RESULTSAmong the 285 eligible patients, groups L and H consisted of 118 and 167 patients, whose mean ages were 68.6 and 68.3 years, respectively. There was a significant difference in body mass index (22 vs 24 mg/kg2, respectively, p = 0.000), PNI (46 vs 55, p = 0.000), comorbidity of osteoporosis (50% vs 32%, p = 0.005) and autoimmune disease (13% vs 5%, p = 0.036), medical history of malignant disorder (17% vs 6%, p = 0.007), and medical complications (49% vs 23%, p = 0.000) between groups L and H. Multiple logistic regression analysis suggested that significant risk factors for postoperative medical complications were male sex (p = 0.000, OR 3.5, 95% CI 1.78–6.96), PNI < 50 (p = 0.000, OR 2.9, 95% CI 1.69–4.93), and days to ambulation (p = 0.003, OR 1.1, 95% CI 1.02–1.09).CONCLUSIONSMedical complication rates are significantly higher in patients with PNI < 50, those with delayed ambulation, and male patients. In malnourished patients scheduled for ASD surgery, improvement of preoperative nutritional status and postoperative early ambulation are important to avoid medical complications.

Introduction: Chronic low back pain (CLBP) is a major health burden worldwide and requires patient satisfaction with treatment. Consultation length can be an important factor in patient satisfaction, but few studies have investigated the impact of consultation length on satisfaction in patients with CLBP. This study tried to elucidate the impact of consultation length on clinical outcomes in patients with CLBP. Methods: This study is part of an analysis using the database of the nationwide, multicenter cohort for CLBP performed by the Project Committee of the Japanese Society for Spine Surgery and Related Research. A total of 427 patients aged 20-85 years (median age, 73.0 years; female, 58.6%) with CLBP were prospectively followed-up monthly for 6 months. Multivariable nonlinear regression analyses were performed to assess the effect of consultation length on outcome measures including subjective satisfaction score, EuroQol 5-dimension, Japanese Orthopaedic Association (JOA) score, Roland-Morris Disability Questionnaire, JOA Back Pain Evaluation Questionnaire, visual analog scale (VAS) and Medical Outcome Survey short-form 8-item health survey that evaluated at the next phase. Furthermore, we assessed whether the effect of consultation length on patient satisfaction was modified by the baseline Brief Scale for Psychiatric Problems in Orthopaedic Patients (BS-POP) score for patient and physician versions. Results: VAS for CLBP was the only score that correlated significantly with consultation length (P = 0.018). Satisfaction score showed a significant positive correlation with consultation length in patients with the highest baseline BS-POP scores (P < 0.2). Moreover, consultation lengths more than 7.6 min and 15.1 min offered increase of satisfaction if patients show the highest BS-POP scores on patient and physician versions, respectively. Conclusions: These findings suggest that a sufficiently long consultation is an important factor for subjective satisfaction in the patients with CLBP, particularly in patients with psychological problems.

Several studies indicated the influence of age and sex on spinal alignment using spino-pelvic radiographic parameters. However, information regarding the geometrical assessment of the sagittal spinal plane in the elderly population remains limited. This study aimed to determine the apices of lumbar lordosis and thoracic kyphosis, and spinal inflection point in elderly individuals and clarify the effect of age, sex, and pelvic incidence (PI) on sagittal geometry.In total, 440 volunteers (193 men; 247 women) were enrolled. The spino-pelvic radiographic parameters were measured. The apices of thoracic kyphosis and lumbar lordosis, and the inflection point where the vertebral curvature changes from kyphosis to lordosis were investigated. We analyzed the differences in the sagittal curve shape according to the sex, age, and PI magnitude.On average, the apices of thoracic kyphosis and lumbar lordosis, and the inflection point were located at the levels of the T8/9 intervertebral disc, L3/4 disc, and L1 vertebra, respectively. Significant differences between men and women were observed with respect to the spino-pelvic parameters; however, the positions of the apices were significantly different only with respect to the lumbar apex offsets among individuals in their 70s. The inflectional point and apex of thoracic kyphosis among individuals aged80 years were located significantly anteriorly and caudally in comparison to those among individuals aged69 years. The apex of lumbar lordosis and the inflection point in individuals with high PI were located significantly anteriorly and cranially in comparison to those in individuals with low PI.The apices of thoracic kyphosis and lumbar lordosis, and the inflection point were located at the T8/9 intervertebral disc, L3/4 disc, and L1 vertebra, respectively. The shape of the sagittal spinal curve varied according to age and the magnitude of PI, and these findings cannot be evaluated using the conventional spino-pelvic parameters. Knowledge of standard geometrical spine shape could be useful for spinal deformity treatment in elderly patients.

Study design This was a retrospective analysis of a prospectively collected consecutive case series of patients with adult spinal deformity (ASD). Objective This study aimed to investigate the impact of the geometrical sagittal shape of the corrected spine on the development of proximal junctional kyphosis (PJK). Several studies have documented risk factors for PJK in ASD surgery. Geometrical assessment is vital for evaluating sagittal spinal deformity. It is essential to assess the postoperative geometrical shape of the spine and the location of the correction in the spine to decrease postoperative junctional stress and PJK. Methods Consecutive patients with ASD who underwent corrective fusion with long constructs to the pelvis were included. Patients with neuromuscular disease, congenital and adolescent scoliosis, infection, and spinal tumor were excluded. We investigated the spinopelvic and geometrical parameters of the whole spine. The locations of the thoracic and lumbar apical vertebrae and the inflection vertebrae (IV), where the curvature of the associated adjacent vertebral bodies changes from kyphosis to lordosis, were investigated. The subjects were divided into PJK included patients who underwent revision surgery for junctional failure or with a change in proximal junctional angle ≥ 20°, and non-PJK groups. Results A total of 139 patients (mean age, 69.6 years; range 18-82 years) were included. There were 47 and 92 patients in the PJK and non-PJK groups, respectively. The IV were located significantly cranial and posterior, the lumbar apex were located significantly posterior in the PJK group at the immediate postoperative time points. The significant risk factors for PJK on binary logistic regression were cranial IV and posterior lumbar apical vertebrae. The incidence of PJK in patients with IV at T12 or cranial tends PJK significantly higher (69%) than at L1 or caudal (26%). Conclusions Geometrical spinal shape should be taken into account to reduce the rate of postoperative mechanical complications. Level of evidence Level of evidence III.

Upper instrumented vertebra (UIV) fracture in adult spinal deformity surgery leads serious complications, such as spinal cord injury in 0.5–0.8%. Although tip-apex distance is important for preventing screw cut-out in proximal femoral fracture surgery, this suggest that the screw occupancy rate for bone fragments is also important. The purpose of this study was to investigate how the occupancy rate of pedicle screws (ORPS) affects UIV fracture. Patients with UIV fracture 1 year after surgery were defined as the fracture group (F); others were defined as the no fracture group (NF). ORPS, cut-out of pedicle screw (PS), medications, and bone mineral density were evaluated. Significant differences (P

OBJECTIVEThe Scoliosis Research Society-22r questionnaire (SRS-22r) has been shown to be reliable, valid, and responsive to change in patients with adult spinal deformity (ASD) undergoing surgery. The minimal clinically important difference (MCID) is the smallest difference in a health-related quality of life score that is considered to be worthwhile or clinically important to the individual. The authors hypothesized that the proportion of patients with ASD achieving an MCID in the SRS-22r score would be different between two culturally different cohorts. The purpose of this study was to compare the proportion of patients with ASD achieving MCID for the SRS-22r domains in North American (NA) and Japanese cohorts.METHODSA total of 137 patients from North America (123 women, mean age 60.0 years) and 60 patients from Japan (56 women, mean age 65.5 years) with at least 2 years of follow-up after corrective spine surgery for ASD were included. Except for self-image, published Japanese MCID values of SRS-22r for ASD were higher (function = 0.90, pain = 0.85, self-image = 1.05, subtotal = 1.05) than the published NA MCID values (function = 0.60, pain = 0.40, self-image = 1.23, subtotal = 0.43).RESULTSThere was a statistically significant improvement in all SRS-22r domain scores at 2 years compared to baseline in both cohorts. Except for mental health (NA = 0.32, Japanese = 0.72, p = 0.005), the mean improvement from baseline to 2 years was similar between the NA and Japanese cohorts. The proportion of patients achieving MCID was higher in North America for function (NA = 51%, Japanese = 30%, p = 0.006), pain (NA = 80%, Japanese = 47%, p < 0.001), and subtotal (NA = 72%, Japanese = 35%, p < 0.001), while there was no significant difference for self-image (NA = 53%, Japanese = 58%, p = 0.454).CONCLUSIONSDespite similar improvements in SRS-22r domain scores from baseline to 2 years postoperatively, the proportion of patients reaching SRS-22r MCID for function, pain, and subtotal after ASD surgery was higher in the NA cohort than in the Japanese cohort. This may imply that patients in North America and Japan may value observed changes in clinical status differently.

Study Design: Retrospective cohort study.Purpose: This study aimed to investigate how participation in sporting activity affects patient-reported outcome (PRO), including Neck Disability Index (NDI), in males and females.Overview of Literature: Previously, our study reported that factors with a negative influence on the NDI in females were a lack of sporting activities. However, it was still unclear why it affected poor scores of NDI.Methods: The subjects were 473 volunteers. They were divided into two groups (activity and non-activity) according to participation or non-participation in sporting activities using a self-filled questionnaire. The evaluation items were height, weight, grip strength, bone density, Hospital Anxiety and Depression Scale (HADS) score, standing radiographic parameters, PRO (evaluated by EuroQol-5 dimension [EQ-5D], Oswestry Disability Index [ODI]), and NDI.Results: There were 101 males in the non-activity group and 69 in the activity group and 178 females in the non-activity group and 125 in the activity group. For the males, the evaluation items with significant influence were cervical lordosis (non-activity group:activity group, 17°:22°) and T1 slope minus cervical lordosis (10°:6°, p p

The study aimed to examine the factors affecting the clinical outcomes of anterior talofibular ligament (ATFL) repair surgery with arthroscopy for chronic lateral ankle instability (CLAI). From 2015 to 2018, 18 consecutive patients diagnosed with CLAI after conservative treatment for 3 months or more underwent arthroscopic ATFL repair surgery using the Broström-Gould technique. Clinical scores at 1 year postoperatively involving the Karlsson scoring scale (median, 85 points) and the Japanese Society for Surgery of the Foot scale (median, 90 points) were significantly improved compared to preoperative scores (median, 50 and 66 points; p, 発行年：2020年5-6月

Study design Retrospective multicenter cohort study. Objective We evaluated a new upper instrumented vertebra (UIV) selection method that used the modified Shinshu line (MSL) to establish the selected UIV as the MSL vertebra (MSLV). Summary of background data No reports have addressed optimal UIV selection according to the lower instrumented vertebra (LIV) for good trunk balance in Lenke 1A curves. Methods Forty-five consecutive patients (44 female, 14.4 ± 2.4 yrs) receiving posterior spinal fusion (PSF) for a Lenke 1A adolescent idiopathic scoliosis (AIS) curve were analyzed. We defined the novel MSL as the line between the center of the spinous process of C7 and that of the spinous process of the LIV. The vertebral body with which the MSL first contacted proximally was defined as the MSLV. The groups in which the UIV was at, proximal to, or distal to the MSLV were defined as the matched group (M-group; 15 cases [15 female], 14.7 ± 2.1 yrs), proximal group (P-group; 20 cases, [19 female], 15.0 ± 2.2 yrs), and distal group (D-group; 10 case [10 female], 14.8 ± 2.5 yrs), respectively. We measured Cobb angle, main thoracic (MT) curve correction rate, and C7 plumb line absolute value (C7PL) at pre- and 2 years postoperatively for comparisons using Dunnett test, with the M-group as the control. Results In the M-group, P-group, and D-group, the Cobb angle correction rate between pre- and postoperative time points were 65.3 ± 1.3%, 62.4 ± 1.6%, and 52.8 ± 6.8%, respectively, and comparable apart from a smaller correction tendency in the D-group versus the M-group (P = 0.08). At 2 years postoperatively, C7PL was 0.5 ± 0.4, 1.0 ± 0.6, and 1.3 ± 0.9 cm, respectively, and significantly smaller for the M-group (both P Conclusion Better trunk balance were obtained without reducing correction rate by setting the novel MSLV as the UIV in PSF for Lenke type 1A curves. Level of evidence 3.

Study design Four-year, longitudinal cohort study. Objective To investigate the effect of original spinal shape on incidental vertebral fractures and to identify the influence of changes in pre- and post-fracture geometrical spinal shape. Summary of background data Clinical evidence demonstrates that vertebral fractures cause spinal kyphosis, morbidities, and deteriorating quality of life in elderly people. However, knowledge of geometrical spinal shapes that affect incidental vertebral fractures is limited. Methods Three hundred and seventeen volunteers underwent whole spine radiography as part of a health screening in both 2012 and 2016. We extracted volunteers with incidental vertebral fracture in 2016. Sex- and age-matched volunteers without vertebral fracture were enrolled as controls. Baseline demographic variables, geometrical spinal shape, and spinopelvic parameters were compared between the two groups. In volunteers with incidental vertebral fracture, we investigated the association between baseline spinal shape and post-fracture shape. Results Twenty-seven volunteers (12 men; mean age 75.4 ± 5.4 and 15 women; mean age 71.6 ± 7.9) with vertebral fracture were enrolled, and 175 volunteers (48 men, 127 women) without vertebral fracture were selected as controls. In men with vertebral fracture, the thoracic kyphosis apex was located significantly more posteriorly and caudally than in those without vertebral fracture. In women with vertebral fracture, the lordosis apex was located significantly more posteriorly and caudally than in those without vertebral fracture. After fractures occurring above the inflexion vertebra, the low anterior apex spine (L5) changed its geometrical shape in that the posterior apex and the inflexion vertebra shifted significantly more posteriorly compared to the high anterior apex spine (L4/5). Conclusions Original geometrical spinal shape affected the occurrence of vertebral fracture, and post-fracture spinal shape depended on the positional relationship between the inflexion vertebra and fractured vertebra. Our study helps to understand the influence of geometrical spinal shape on the risks of vertebral fracture. Level of evidence 3.

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. 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. 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

Study design Case-control study from a continuous series OBJECTIVES.: To study the impact of perioperative sitting radiographs in adult spinal deformity (ASD) patients and determine whether proximal junctional kyphosis (PJK) can be prevented using preoperative sitting radiograph. Summary of background data Radiographic analysis of ASD comprises standing whole-spine radiography which cannot evaluate the relaxed posture without head-to-foot compensation. Methods Preoperative and postoperative whole-spine standing and sitting radiographs and proximal mechanical complications in surgically treated spinal disorders with a minimum of 1-year follow-up were studued. Whole-spinal alignment was defined by cervical lordosis (CL), sagittal vertical axis (SVA), T1 slope (T1S), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and level of kyphotic apex (KA). Proximal mechanical complication was described as a PJK (proximal junctional angle >20°) or reoperation due to proximal junctional failure. Results Surgically treated 113 patients were prospectively investigated. Patients were divided into either the ASD (thoracic to ilium posterior corrective fusion), or non-ASD groups. In the ASD group, ten patients had postoperative PJK, and three revision surgeries were carried out due to PJF with neurological deficit. Comparing standing with sitting positions, CL, TK, and PT became larger, SVA became frontal, LL and SS became smaller, and KA became caudal particularly in the ASD group. Logistic regression analysis demonstrated that the most influenced plumb line for PJK was the upper instrumented vertebra (UIV) to C2 plumb line distance, with a cutoff value of 115 mm for predicting PJK. Conclusions Our findings highlight the usefulness of sitting spinal alignment evaluation, particularly in ASD patients, with maximum effort of thoracic spine and lower extremity compensation at standing. Mechanical complications such as PJK could be predicted using the distance from the planned UIV to the C2 plumb line in preoperative sitting radiographs. Level of evidence 3.