The Use of High-Density Pedicle Screw Construct with Direct Vertebral Derotation of the Lowest Instrumented Vertebra in Selective Thoracic Fusion for Adolescent Idiopathic Scoliosis: Comparison of Two Surgical Strategies.

STUDY DESIGN: This study was a retrospective case series. PURPOSE: This study was designed to determine whether direct vertebral rotation (DVR) of the lowest instrumented vertebra (LIV) using a high-density (HD) construct can reduce fusion segments without increasing adverse outcomes in selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS). OVERVIEW OF LITERATURE: LIV DVR is used to maximize spontaneous lumbar curve correction and reduce adverse outcomes during STF for AIS. However, evidence is limited on whether LIV DVR can allow a proximally located LIV and reduce fusion segments without increasing adverse outcomes. METHODS: We reviewed consecutive patients with Lenke 1 AIS who underwent STF from 2000 to 2017. The patients were divided into two groups based on the surgical strategy used: low-density (LD) construct without DVR of the LIV (LD group) versus HD construct with DVR of the LIV (HD group). We collected data on the patient's demographic characteristics, skeletal maturity, operative data, and measured radiological parameters in the preoperative and final follow-up radiographs. The occurrence of adding-on (AO) and coronal decompensation was also determined. RESULTS: In this study, 72 patients (five males and 67 females) with a mean age of 14.1±2.3 years were included. No significant differences in the demographics, skeletal maturity, and Lenke type distribution were observed between the two groups; however, the follow-up duration was significantly longer in the LD group (64.3±25.7 months vs. 40.7±22.2 months, p <0.001). The HD group had significantly shorter fusion segments (7.1±1.3 vs. 8.5±1.2, p <0.001) and a more proximal LIV level (12.1±0.9 vs. 12.7±1.0, p =0.009). In the radiological measurements, the improvement of LIV+1 rotation (Nash-Moe scale) was significantly larger in the HD group (0.53±0.51 vs. 0.21±0.41, p =0.008). AO and decompensation occurred in 7 (9.7%) and 4 (5.6%) patients in the HD and LD groups, respectively, without any significant difference between the two groups. CONCLUSIONS: In this study, the HD group had a significantly shorter fusion level and a more proximal LIV than the LD group; however, the two groups had similar curve correction and adverse radiological outcome rates.

Influence of Handgrip Strength and Paraspinal Muscles' Volume on Clinical Outcomes in the Patients With Each Sagittal Imbalance and Lumbar Spinal Stenosis.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: To compare handgrip strength (HGS), paraspinal muscles' (PSM) volume, and their effects on clinical symptom severity between the patients with sagittal imbalance (SI) and symptomatic lumbar spinal stenosis (LSS). METHODS: A total of 54 paired consecutive patients with SI and LSS were enrolled after propensity score matching. Preoperative HGS, cross-sectional area (CSA) of psoas (PS) and multifidus (MF) muscles, and patient-reported measures, including visual analog scale (VAS) for back/ leg pain, Oswestry Disability Index (ODI), and EuroQOL (EQ-5D) were compared between both groups. Within each SI and LSS group, patient-reported measures were compared between high and low HGS subgroups. The correlation of HGS and CSA of PSMs to patient-reported measures was evaluated. RESULTS: There was no difference in HGS between 2 groups, however, the CSA of PS and MF muscles in SI group was significantly lower than those in LSS group. Patients with low HGS showed inferior results for ODI and EQ-5D, compared to those with high HGS subgroup in both SI and LSS groups. HGS and CSA of MF muscle were correlated with ODI in both groups. CONCLUSIONS: There was no significant difference between the SI and LSS groups in HGS, however, PSMs' volume in SI group were significantly lower than those in LSS group. Therefore SI would be associated with loss of localized muscle mass in back area, rather than global skeletal muscle weakness. HGS and PSMs' volume were adversely associated with functional status in SI and LSS patients.

Ice front retreat reconfigures meltwater-driven gyres modulating ocean heat delivery to an Antarctic ice shelf.

Pine Island Ice Shelf (PIIS) buttresses the Pine Island Glacier, the key contributor to sea-level rise. PIIS has thinned owing to ocean-driven melting, and its calving front has retreated, leading to buttressing loss. PIIS melting depends primarily on the thermocline variability in its front. Furthermore, local ocean circulation shifts adjust heat transport within Pine Island Bay (PIB), yet oceanic processes underlying the ice front retreat remain unclear. Here, we report a PIB double-gyre that moves with the PIIS calving front and hypothesise that it controls ocean heat input towards PIIS. Glacial melt generates cyclonic and anticyclonic gyres near and off PIIS, and meltwater outflows converge into the anticyclonic gyre with a deep-convex-downward thermocline. The double-gyre migrated eastward as the calving front retreated, placing the anticyclonic gyre over a shallow seafloor ridge, reducing the ocean heat input towards PIIS. Reconfigurations of meltwater-driven gyres associated with moving ice boundaries might be crucial in modulating ocean heat delivery to glacial ice.

BMP-2 Induced Signaling Pathways and Phenotypes: Comparisons Between Senescent and Non-senescent Bone Marrow Mesenchymal Stem Cells.

The use of BMP-2 in orthopedic surgery is limited by uncertainty surrounding its effects on the differentiation of mesenchymal stem cells (MSCs) and how this is affected by cellular aging. This study compared the effects of recombinant human BMP-2 (rhBMP-2) on osteogenic and adipogenic differentiation between senescent and non-senescent MSCs. Senescent and non-senescent MSCs were cultured in osteogenic and adipogenic differentiation medium containing various concentrations of rhBMP-2. The phenotypes of these cells were compared by performing a calcium assay, adipogenesis assay, staining, real-time PCR, western blotting, and microarray analysis. rhBMP-2 induced osteogenic differentiation to a lesser extent (P < 0.001 and P = 0.005 for alkaline phosphatase activity and Ca2+ release) in senescent MSCs regardless of dose-dependent increase in both cells. However, the induction of adipogenic differentiation by rhBMP-2 was comparable between them. There was no difference between these two groups of cells in the adipogenesis assay (P = 0.279) and their expression levels of PPARγ were similar. Several genes such as CHRDL1, NOG, SMAD1, SMAD7, and FST encoding transcription factors were proposed to underlie the different responses of senescent and non-senescent MSCs to rhBMP-2 in microarray analyses. Furthermore, inflammatory, adipogenic, or cell death-related signaling pathways such as NF-kB or p38-MAPK pathways were upregulated by BMP-2 in senescent MSCs, whereas bone forming signaling pathways involving BMP, SMAD, and TGF- ß were upregulated in non-senescent MSCs as expected. This phenomenon explains bone forming dominance by non-senescent MSCs and possible frequent complications such as seroma, osteolysis, or neuritis in senescent MSCs during BMP-2 use in orthopedic surgery.

The Fate of Lumbar Facet Cyst After Indirect Decompression Using Oblique Lateral Interbody Fusion in Degenerative Spondylolisthesis.

Favorable clinical outcomes have been reported for oblique lateral interbody fusion (OLIF) for various lumbar degenerative diseases. However, there is only limited evidence on the safety and effectiveness of OLIF in degenerative spondylolisthesis with lumbar facet cyst (LFC), and OLIF is often regarded as a relative contraindication for these patients. The authors prospectively enrolled patients who underwent a single-level OLIF for degenerative spondylolisthesis with LFC to evaluate the morphological changes of LFC and their clinical significance following OLIF. Twenty patients with a mean age of 69.6 years (range, 65-86 years) were enrolled. At 1 week postoperative, 5 (25%) patients had a residual cyst, whereas 15 (75%) patients had completely resolved cysts on magnetic resonance imaging (MRI). No patient had a residual cyst on the 1-year postoperative MRI. Patients with cyst resolution (n=15) on the 1-week postoperative MRI had a larger slip percentage difference on the preoperative dynamic radiograph when compared with patients with no cyst resolution (n=5) (4.7%±2.8% vs 1.3%±0.3%, P=.002). The group with cyst resolution also showed a greater expansion of facet fluid width following OLIF, although this was not statistically significant (1.2±0.7 mm vs 0.7±0.5 mm, P=.098). For both groups, all preoperative clinical scores showed a significant improvement at 1 year after OLIF, but there was no significant difference between the groups at all time points. Preliminary 1-year follow-up results from this prospective series suggest that OLIF can be a useful option for fusion surgery in LFC patients with apparent segmental instability. [Orthopedics. 2021;44(5):306-312.].

Involvement of L5-S1 level as an independent risk factor for adverse outcomes after surgical treatment of lumbar pyogenic spondylitis: A multivariate analysis.

PURPOSE: To identify the independent risk factors for adverse outcomes and determine the effect of L5-S1 involvement on the outcome of surgical treatment of lumbar pyogenic spondylitis (PS). METHODS: A retrospective analysis was performed for all consecutive patients who underwent surgery for lumbar PS between November 2004 and June 2020 at a single institution. The patients were divided into two groups based on the outcomes: good and adverse (treatment failure, relapse, or death). Treatment failure was defined as persistent or worsening pain with C-reactive protein (CRP) reduction less than 25% from preoperative measurement or requiring additional debridement. Relapse was defined as the reappearance of symptoms and signs with an elevated white blood cell count, erythrocyte sedimentation rate, and CRP after the first period of treatment. Binary logistic regression analyses were performed to identify the independent risk factors for adverse outcomes. RESULTS: Twenty-four (21.2%) of the 113 patients were classified as having adverse outcomes: treatment failure, relapse, and death occurred in 15, 7, and 2 patients, respectively. The involvement of L5-S1 (adjusted odds ratio [aOR] = 6.561, P = 0.004), Methicillin-resistant Staphylococcus aureus (MRSA) infection (aOR = 6.870, P = 0.008), polymicrobial infection (aOR = 12.210, P = 0.022), and Charlson comorbidity index (CCI; P = 0.005) were identified as significant risk factors for adverse outcomes. CONCLUSION: Involvement of L5-S1, MRSA, polymicrobial infection, and CCI were identified as independent risk factors for adverse outcomes after surgical treatment of lumbar PS. Because L5-S1 is anatomically demanding to access anteriorly, judicious access and thorough debridement are recommended in patients requiring anterior debridement of L5-S1.

Clinical outcomes of selective fusion for the thoracolumbar-lumbar curve in patients with Lenke type 6C adolescent idiopathic scoliosis: a preliminary study.

Limited evidence is available in the literature regarding the fate of the unfused structural thoracic curve following selective thoracolumbar-lumbar curve fusion (SLF) in Lenke 6C adolescent idiopathic scoliosis (AIS) patients. Therefore, we compared the outcomes of SLF between Lenke 6C and 5C AIS patients. We retrospectively reviewed 31 patients Lenke 5C (n = 18) and Lenke 6C (n = 13) AIS patients who underwent SLF at a single institution. Multiple radiological parameters were measured using whole-spine radiographs taken before and after surgery and at the last follow-up visit. SRS-22 at the final follow-up was obtained for clinical assessment. A total of 31 patients with a mean age of 14.6 years at operation who were followed for a mean of 6.4 years were included in this study. The Cobb angle of the unfused thoracic curve was spontaneously corrected immediately following SLF and increased slightly but not significantly at the final follow-up in both groups (Lenke 5C: pre 33.0°, post 14.4°, final 19.4°, Lenke 6C: pre 46.1°, post 31.7°, final 34.2°). At every time point, the thoracic Cobb angle was significantly larger in the Lenke 6C. SRS-22 score at the final follow-up, including the self-image domain, did not differ between the two groups. In this study, SLF for Lenke 6C AIS achieved a significant spontaneous correction of the unfused thoracic curve and yielded a comparable SRS-22 result at the final follow-up to that of Lenke 5C. Our findings suggest that SLF is a viable treatment option for Lenke 6C AIS.

Sagittal Alignment in Patients with Thoracic Myelopathy Caused by the Ossification of the Ligamentum Flavum: A Retrospective Matched Case-Control Study.

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: The aim of this study was to describe and compare the sagittal spinal alignment between patients with and without the ossification of the ligamentum flavum in the thoracic spine (TOLF). SUMMARY OF BACKGROUND DATA: Although mechanical factors play an important role in the development of TOLF, limited evidence exists on the association of sagittal spinal alignment and TOLF in the literature. METHODS: The present study assessed the preoperative sagittal alignment parameters in consecutive patients who underwent posterior decompression for TOLF in a single institution between January 2014 and December 2019. The sagittal parameters of the patients with TOLF were compared to those of the age- and sex-matched control group with lumbar spondylosis. RESULTS: The TOLF group (n = 43 [23 men, 20 women]), with a mean age of 69.5 (range: 41-86) years, and the control group (n = 86) were compared. The TOLF group had a significantly smaller sacral slope (27.60 ±â€Š7.49 vs. 30.61 ±â€Š8.15, P = 0.045) and lumbar lordosis (36.84 ±â€Š13.63 vs. 45.08 ±â€Š9.90, P < 0.001) and a larger pelvic incidence minus lumbar lordosis (PI-LL, 8.06 ±â€Š15.05 vs.1.00 ±â€Š11.34, P = 0.004) than the control group. Moreover, the thoracic kyphosis was smaller in the TOLF group, although the difference was not statistically significant (25.73 ±â€Š11.29 vs. 28.22 ±â€Š9.34, P = 0.187). The TOLF group had a significantly smaller slope angle at the inflection point (11.97 ±â€Š5.85 vs. 15.78 ±â€Š5.62, P < 0.001) and a higher tendency to have a Roussouly type 2 morphology (46.5% vs. 36.0%, P = 0.252) than the control group. CONCLUSION: This is the first study to describe the sagittal alignment in patients with TOLF. The TOLF group showed a hypolordotic spine with a larger PI-LL mismatch compared to the age- and sex-matched control group with lumbar spondylosis.Level of Evidence: 4.

Risk factors for postoperative ileus after oblique lateral interbody fusion: a multivariate analysis.

BACKGROUND CONTEXT: Oblique lateral interbody fusion (OLIF)-has become a widely used, efficient surgical tool for various degenerative lumbar conditions. Postoperative ileus (POI) is a relatively common complication after anterior lumbar interbody fusion due to the manipulation of the intestine during the surgical approach. However, to our knowledge, little is known about POI following OLIF even though it also involves bowel manipulation during a surgical procedure. PURPOSE: To assess the incidence of POI and identify independent risk factors for POI development after OLIF. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: All consecutive patients who underwent OLIF and percutaneous pedicle screw instrumentation from August 2012 until October 2019 at a single institution OUTCOME MEASURES: Patient demographics (sex, age, body weight, height, and body mass index), comorbidities (diabetes mellitus, gastroesophageal reflux disease, antithrombotic medication, previous abdominal surgery, and previous lumbar surgery), and perioperative details (preoperative diagnosis, number of levels fused, inadvertent endplate fracture during cage insertion, type of interbody graft, intraoperative estimated blood loss, duration of surgery and anesthesia, the amount of intraoperative remifentanil and propofol used as anesthetic agents, the total postoperative retroperitoneal closed-suction drainage output, and the cumulative opioid dosage administered in the first 72 hours postoperatively). METHODS: POI was defined as 2 or more of the following at 72 hours postoperatively: (1) ongoing nausea or vomiting postoperatively, (2) the absence of flatus over last 24-hour period, (3) inability to tolerate an oral diet over last 24-hour period, (4) ongoing abdominal distention postoperatively, and (5) radiological confirmation. The subjects were divided into 2 groups: patients with POI and those without POI. Binary logistic regression analyses were performed on demographics, comorbidities, and perioperative factors to identify independent risk factors for POI. RESULTS: Eighteen (3.9%) of 460 patients experienced POI after OLIF and percutaneous pedicle screw instrumentation. Patients with POI had a significantly longer postoperative length of hospital stay than those without POI (8.61 ± 2.66 vs 6.48 ± 2.64, p = .001). Multivariate logistic regression analysis identified inadvertent endplate fracture (adjusted odds ratio = 6.017, p = .001) and the amount of intraoperative remifentanil (adjusted odds ratio = 1.057, p = .024) as independent risk factors for the occurrence of POI following OLIF. CONCLUSION: This study identified inadvertent endplate fracture and the amount of intraoperative remifentanil as independent risk factors for the development of POI after OLIF.

Influence of Hand Grip Strength on Surgical Outcomes After Surgery for Adult Spinal Deformity.

STUDY DESIGN: A prospective observational study. OBJECTIVE: This study was done to examine the influence of hand grip strength (HGS) on surgical outcomes of adult spinal deformity (ASD) patients. SUMMARY OF BACKGROUND DATA: No study has investigated the relation between hand grip strength and treatment outcome of adult spinal deformity correction surgery. METHODS: A total of 78 consecutive patients who underwent adult spinal deformity correction surgery were included in this study. Patients were assigned to either the high HGS (≥ 26 kg for men and ≥ 18 kg for women, n = 26) or the low HGS (< 26 kg for men and < 18 kg for women, n = 52) based on their preoperative measurements. The Oswestry disability index (ODI), EQ-5D, and visual analog scale (VAS) for back pain were assessed preoperatively, and 3 months, 6 months, and 12 months postoperatively. The primary outcome measure was ODI scores 12 months after surgery. The secondary outcome measures included the overall ODI scores, EQ-5D, and VAS for back pain, assessed at each time point during the 12-months follow-up. RESULTS: The ODI score at 12 months after surgery was significantly lower in the high HGS group than the low HGS group (P < 0.001), which was best predicted by a multivariate regression model including age, gender, BMI, HGS, and preoperative ODI scores. The overall ODI score, EQ-5D, and VAS for back pain had better outcomes in the high HGS group across each follow-up assessment (P < 0.001 for all follow-ups), while they improved significantly with time after surgery in both groups. CONCLUSIONS: Patients with higher preoperative HGS displayed better surgical outcomes, in terms of disability and health-related quality of life at 12 months after reconstructive spinal surgery for ASD. LEVEL OF EVIDENCE: 2.

The impact of COVID-19 pandemic on orthopaedic resident education: a nationwide survey study in South Korea.

PURPOSE: There have not been well-designed survey studies investigating the impact of the coronavirus disease 2019 (COVID-19) pandemic on orthopaedic resident education. METHODS: A 58-question, web-based survey was administered to orthopaedic residents in South Korea. A total of 229 orthopaedic residents from 43 hospitals completed the survey questionnaire. RESULTS: The average working time of 72.7 hours/week before the pandemic was decreased to 65.6 hours/week during the pandemic (p < 0.001). The time working in the operating room was significantly decreased during the pandemic, but not in the emergency centre and outpatient clinic. The education times for lecture and clinical case discussion were decreased during the pandemic (both, p < 0.001), respectively. While the use of traditional teaching methods was decreased, the use of online-based teaching methods was increased (p < 0.001). However, satisfaction level with online-based teaching methods was significantly lower compared with that of traditional teaching methods. The average working time exposed to the patients with COVID-19 was 9.7 hours/week. About 47.6% of orthopaedic residents experienced isolation or quarantine. The average score for quality of life, which was 68.9 out of 100 scores before the pandemic, decreased to 61.7 during the pandemic (p < 0.001). The most stressful factor for orthopaedic residents during the pandemic was family/relative health, followed by their own health and residency program. CONCLUSION: The COVID-19 pandemic had a significant impact on orthopaedic resident education in South Korea. Therefore, flexible and sustainable strategies are necessary to prepare for the future as well as the current pandemic situation.

Predictive Value of Comprehensive Geriatric Assessment on Early Postoperative Complications Following Lumbar Spinal Stenosis Surgery: A Prospective Cohort Study.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: The aim of this study was to evaluate the predictive value of comprehensive geriatric assessment (CGA) for early postoperative complications in elderly patients (aged 65 years or older) following lumbar spinal stenosis surgery. SUMMARY OF BACKGROUND DATA: CGA is a multidisciplinary evaluation modality proven to be effective in various fields of geriatrics. However, limited evidence exists on the effectiveness of CGA in lumbar spinal stenosis patients in the literature. METHODS: We prospectively enrolled consecutive patients who were at least 65 years' old and were scheduled to undergo elective surgery for lumbar spinal stenosis. One day before the operation, multidomain CGA was performed on the patient's functional status, comorbidities, nutrition, cognition, and psychological status. Patients with deficits in three or more CGA domains were defined as frail. The occurrence of postoperative complications (Clavien and Dindo grade 2 or higher) within 30 days after the surgery was assessed as the outcome. The predictive value of CGA was evaluated using crosstab and logistic regression analysis and compared to that of other risk stratification systems, including modified Frailty Index-5, -11, and American Society of Anesthesiologists Physical Classification System. RESULTS: A total of 261 patients were included in the study, and 25 (9.6%) patients were assigned to the "frail" group. There were 27 (10.3%) patients with a postoperative complication (general: n = 20, 7.7%, surgical: n = 7, 2.7%) within postoperative 30 days. Patients with a complication showed significantly more deficits on preoperative CGA than those without complications (P = 0.004). On multivariate logistic regression analysis, frailty based on CGA (odds ratio = 3.51, P = 0.031) and the modified Frailty Index-11 (odds ratio = 3.13, P = 0.038) were associated with the occurrence of general complications. CONCLUSION: Frailty based on CGA was significantly associated with early general complications following surgery for lumbar spinal stenosis in patients older than 65 years. LEVEL OF EVIDENCE: 2.

Clinical Significance of Radiologic Improvement Following Single-Level Oblique Lateral Interbody Fusion With Percutaneous Pedicle Screw Fixation.

Indirect decompression using oblique lateral interbody fusion (OLIF) improves spinal canal dimensions by reducing spondylolisthesis and restoring intervertebral disk height in patients with degenerative lumbar diseases. However, the clinical significance of these radiological improvements has not been fully evaluated in the literature. To examine the relationship between the clinical and radiological outcomes following OLIF, the authors prospectively studied 41 patients who underwent single-level OLIF with percutaneous pedicle screw fixation for lumbar degenerative disease, including degenerative and spondylolytic spondylolisthesis and spinal stenosis with disk height loss. Clinical scores were obtained preoperatively and at 1 year postoperatively using multiple questionnaires. Radiological outcomes were evaluated using plain radiographs, computed tomography (CT) scans, and magnetic resonance imaging (MRI) at 1 year postoperatively. Following a single-level OLIF, all categories of clinical scores showed statistically significant improvement. Rate of cage subsidence was 14.6% and 31.7% at 1 week and 1 year postoperatively, respectively. Patients with subsidence had higher Oswestry Disability Index (P=.026) scores and lower physical composite summary scores on the Short Form-36 Health Survey (P=.007). On CT scan, 28 (68.3%) patients showed a complete interbody fusion and 13 (31.7%) had intermediate fusion. All parameters from the MRI, except for foraminal width, showed significant improvement at 1 year postoperatively. The improvement ratio of foraminal height was associated with the percent improvement of lower-extremity radiating pain (Pearson coefficient=0.384; P=.013) and the walking ability score of the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (Pearson coefficient=0.319; P=.042) at 1 year postoperatively. Restoration of foraminal height while preserving the endplates is associated with favorable results following OLIF. [Orthopedics. 2020;43(4):e283-e290.].

Definitions of unfavorable surgical outcomes and their risk factors based on disability score after spine surgery for lumbar spinal stenosis.

BACKGROUND: Risk factors for unfavorable surgical outcomes are dependent on the definitions of the unfavorable surgical outcomes. The aims of this study were to compare risk factors for each unfavorable surgical outcome according to two different definitions of "unfavorable" surgical outcomes after surgery for lumbar spinal stenosis (LSS) as well as compare the clinical course from the preoperative period to 3 years postoperatively between cases with favorable and unfavorable outcomes according to the two different definitions. METHODS: Overall, 295 patients who underwent spine surgery for LSS and a follow-up evaluation at 3 years postoperatively were enrolled and divided into favorable and unfavorable groups, based on two different definitions for unfavorable surgical outcomes, as evaluated at 12 months postoperatively: the patient-reported outcome (PRO) and minimal clinically important difference (MCID) methods. In the PRO method, patients with a postoperative Oswestry Disability Index (ODI) score > 22 were considered as having an "unfavorable" outcome, whereas in the MCID method, those with a postoperative ODI score that changed < 12.8 points from the preoperative value were classified as having an "unfavorable" outcome. As a primary outcome, risk factors for unfavorable surgical outcomes according to each definition were investigated at 12 months postoperatively. RESULTS: In the PRO method, female sex (P = 0.011; odds ratio (OR): 2.340), elementary school attainment (vs. university attainment; P = 0.035; OR: 2.875), and higher preoperative ODI score (P = 0.028; OR: 2.340) were associated with higher odds for an unfavorable surgical outcome. In the MCID method, a higher preoperative ODI score was associated with higher odds (P <  0.001; OR: 0.920) of a favorable surgical outcome. In the PRO method, the favorable outcome group demonstrated significantly lower visual analog scale for back and leg pain and lower ODI scores than the unfavorable outcome group at 3 years postoperatively, whereas in the MCID method, clinical outcomes were not different between the two groups at 3 years postoperatively. CONCLUSION: A higher preoperative ODI score may be a risk factor for postoperative ODI > 22 after surgery for LSS. It may also be associated with higher odds for improvements in the ODI score of > 12.8.

A Long-Term Follow-up, Multicenter, Comparative Study of the Radiologic, and Clinical Results Between a CaO-SiO2-P2O5-B2O3 Bioactive Glass Ceramics (BGS-7) Intervertebral Spacer and Titanium Cage in 1-Level Posterior Lumbar Interbody Fusion.

STUDY DESIGN: This is a prospective, stratified randomized, multicenter, 4-year follow-up study. OBJECTIVE: The authors aimed to evaluate the long-term clinical efficacy and safety of CaO-SiO2-P2O5-B2O3 glass ceramics (BGS-7) spacers in 1-level posterior lumbar interbody fusion (PLIF) at a 4-year follow-up. SUMMARY OF BACKGROUND DATA: According to 1-year follow-up results, BGS-7 spacer showed similar fusion rates and clinical outcomes compared with titanium cage. A long-term follow-up study beyond 2 years is necessary to investigate the status of intervertebral bone graft volumes. Moreover, longer follow-up is mandatory to also evaluate the safety and efficacy of BGS-7 spacers, because they remain in the intervertebral space for a long time. MATERIALS AND METHODS: In this prospective, randomized, multicenter, 4-year follow-up study, we evaluated 62 of the 74 patients who underwent 1-level PLIF. During 1-level PLIF, titanium cages filled with autologous local bone were inserted into the control group patients and BGS-7 spacers were inserted to the experimental group patients. Bone fusion was evaluated by plain radiography and thin-section computed tomography. Visual Analog Scale (VAS), the Oswestry Disability Index (ODI), Short Form-36 Health Survey (SF-36), and evaluation of safety were conducted after 48 months. RESULTS: Computed tomography scan showed a bone fusion rate of 90.6% in the BGS-7 spacer group and 93.3% in the control group, with no significant differences between groups. The BGS-7 spacer group showed a significantly larger area directly fused to the endplate than the control group (P<0.001). The BGS-7 spacer group showed a significant increase in the fused area compared with the titanium group at 1- and 4-year follow-up. The ODI, SF-36, back pain, and lower limb pain in both groups showed significant improvement after surgery, and no significant differences were observed between the groups. Both groups showed no additional adverse events. CONCLUSIONS: The 4-year follow-up study showed similar fusion rates and clinical outcomes in both the BGS-7 spacer and autologous bone with a titanium cage in 1-level PLIF. However, the BGS-7 spacer implants showed a larger area of fusion with the endplates than that of autologous bone with a titanium cage. Therefore, the results demonstrated that the BGS-7 spacer can be considered as a novel intervertebral spacer to achieve successful spinal fusion without safety concerns for long-term use.

Kaposiform Hemangioendothelioma in Adolescent-Onset Scoliosis: A Case Report and Review of Literature.

Background and Objectives. Kaposiform hemangioendothelioma (KHE) is a vascular tumor of very low incidence, which occurs mostly in children and infants. The tumor is recognized for its locally aggressive, yet rarely metastatic behavior. It may cause consumptive coagulopathy known as Kasabach-Merritt phenomenon. We report a distinctive case, where an 11-year-old boy is presented with progressive thoracolumbar scoliosis without any symptom or neurological sign. Case Report. The patient underwent spinal deformity correction via posterior pedicle screw instrumentation and fusion, along with tumor biopsy. The pathology report confirmed KHE. The patient did not show a prominent progression of scoliosis after the surgery without any further treatments. Conclusions. Many of scoliotic patients do not have any apparent cause, thereby regarded as idiopathic scoliosis. The presented case is where kaposiform hemangioendothelioma is likely to be linked to the patient's scoliosis. We demonstrate the possibility of secondary scoliosis should always be kept in mind of orthopaedic doctors. We also conclude that secondary scoliosis does not show exacerbation after growth completion.

Sleep Disturbance in Patients With Lumbar Spinal Stenosis: Association With Disability and Quality of Life.

STUDY DESIGN: This was a cross-sectional cohort study. OBJECTIVE: The objective of this study was to identify the prevalence of sleep disturbance in patients with symptomatic lumbar spinal stenosis (LSS) and to establish the relationship between sleep disturbance and both functional disability and health-related quality of life in patients with symptomatic LSS. SUMMARY OF BACKGROUND DATA: Despite the possible association between LSS and poor sleep quality, there has been no study regarding the relationship between LSS and sleep disturbance. MATERIALS AND METHODS: A total of 148 patients with LSS were divided into the poor sleeper and nonpoor sleeper groups according to Global Pittsburgh Sleep Quality Index (PSQI) score. Demographic data, Visual Analog Scale (VAS) score for back and leg pain, Oswestry Disability Index (ODI), and EuroQol 5-dimension questionnaire (EQ-5D) were compared between both groups. Multiple regression analysis was performed with ODI or ODI without sleep component as the dependent variable and age, sex, PSQI, VAS for back pain, VAS for leg pain as independent variables. RESULTS: Of the 148 patients who participated in this study, 54 (36.5%) and 94 (63.5%) patients were classified into nonpoor sleeper and poor sleeper groups. Although there were no differences in demographic data or VAS for back or leg pain between the nonpoor sleeper and poor sleeper groups, poor sleepers demonstrated significantly higher ODI scores, and lower EQ-5D than nonpoor sleepers (P=0.003 and 0.004, respectively). There were significant correlations between the global PSQI score and both the ODI score and EQ-5D. Although the surgical treatment group showed significantly higher VAS for back pain, VAS for leg pain, ODI scores, and lower EQ-5D than the conservative treatment group, the ratio of poor to nonpoor sleepers was not different between both groups (P=0.733). In the surgical treatment group, the percent of poor sleeper decreased from 65.1% to 47.6% 6 months after surgery (P<0.001). CONCLUSIONS: The present study demonstrated that 'poor sleep quality' is a prevalent condition (63.5%) in patients with symptomatic LSS. Poor sleep quality has an adverse effect on functional disability and health-related quality of life in symptomatic LSS patients.

Analysis of pelvic compensation for dynamic sagittal imbalance using motion analysis.

PURPOSE: To analyze pelvic compensation during walking in patients with severe sagittal plane deformity by using motion analysis. METHODS: A total of 44 patients with sagittal plane deformity who were scheduled to undergo surgery were included. Motion analysis was performed 3 consecutive times during walking to estimate the anterior pelvic tilt (Ant-PT) angle, trunk kyphosis (TK) angle, and distance of the center of gravity (CoG) from the center of mass (CoM) of the pelvic segment, and hip and knee joint angles during gait. The patients were classified into Ant-PT+/Ant-PT-, TK+/TK-, and CoG+/CoG- groups according to the changes in Ant-PT angle, TK angle, and distance of the CoG from the CoM of the pelvic segment. Increases and decreases in the values of the variables from the first trial to the third trial were indicated with "+" and "-" signs, respectively. RESULTS: The mean Ant-PT angle, TK angle, and distance of the CoG from the CoM of the pelvic segment increased progressively, and the differences in the values of these variables from the first to the third trials were statistically significant (P = 0.046, P = 0.004, and P = 0.007 for the Ant-PT angle, TK angle, and distance of the CoG from the CoM of pelvic segment, respectively). Among the 44 patients, 27 and 34 were classified into the Ant-PT+ and CoG+ groups, respectively. Older age and higher body mass index (BMI) were significantly associated with the Ant-PT+ group. The CoG+ group demonstrated a significantly higher height and weight than the CoG- group. CONCLUSIONS: Higher BMI, height, and weight are risk factors for progressive worsening of dynamic sagittal imbalance. These slides can be retrieved under Electronic Supplementary Material.

Biportal endoscopic versus microscopic lumbar decompressive laminectomy in patients with spinal stenosis: a randomized controlled trial.

BACKGROUND CONTEXT: Biportal endoscopic decompressive laminectomy is a widely performed procedure and shows acceptable clinical outcomes. However, the evidence regarding the advantages of biportal endoscopic surgery is weak, a randomized controlled trial is therefore warranted. PURPOSE: To compare the clinical efficacies of biportal endoscopic and microscopic decompressive laminectomy in patients with lumbar spinal stenosis. STUDY DESIGN: Randomized controlled trial. PATIENT SAMPLE: Sixty-four participants suffering from low back and leg pain with single-level lumbar spinal stenosis who required decompressive laminectomy. OUTCOME MEASURES: Outcomes were assessed with the use of patient-reported outcome measures, visual analog scale (VAS) score for low back and lower extremity radiating pain, Oswestry disability index (ODI), European Quality of Life-5 Dimensions (EQ-5D) score, and painDETECT for neuropathic pain. Surgery-related outcomes including operation time, length of hospital stay, postoperative drainage, and serum creatine phosphokinase were evaluated. Perioperative (<30 days) and late (1-12 months) complications were also noted. METHODS: All participants were randomly assigned in a 1:1 ratio to undergo biportal endoscopic or microscopic decompressive laminectomy. The primary outcome was the ODI score at 12 months after surgery based on a modified intention-to-treat strategy. The secondary outcomes included VAS score for low back and lower extremity radiating pain, ODI scores, EQ-5D score, and painDETECT score. There were no sources of funding and no conflicts of interest associated with this study. RESULTS: There was no significant difference between groups in the mean ODI score at 12 months after surgery (30 in the microscopy vs. 29 in the biportal endoscopy group, p=.635). There were also no significant differences in low back and lower extremity pain VAS scores, ODI, EQ-5D scores, and painDETECT scores at the 3-, 6-, or 12-month follow-up. Operation time, length of hospital stay, serum creatine phosphokinase, and perioperative complications, such as durotomies and symptomatic hematoma, showed no significant differences between the groups; however, one participant underwent additional revision surgery 9 months after the index surgery in the microscopy group. CONCLUSIONS: Despite the study design limitation of relatively short duration of follow-up, this trial suggests that biportal endoscopic decompressive laminectomy is an alternative to and offers similar clinical outcomes as microscopic open surgery in patients with symptomatic lumbar spinal stenosis.

Clinical Significance of Improved Intraoperative Neurophysiological Monitoring Signal during Spine Surgery: A Retrospective Study of a Single-Institution Prospective Cohort.

STUDY DESIGN: Retrospective case series. PURPOSE: We reviewed the cases that showed significant improvement of intraoperative neurophysiological monitoring (IONM) signals during spine surgery to assess whether there is a correlation with signal improvement and postoperative clinical status and its clinical significance. OVERVIEW OF LITERATURE: To reduce the risk of neural injury, many spine surgeons are using multimodality IONM. Although many studies attempted to identify valid alarm criteria for predicting postoperative neurologic deterioration, studies concerning the improvement of IONM signals are rare. METHODS: We reviewed all spine surgery cases with IONM data treated at our department between January 2013 and May 2017. We found cases showing significant IONM signal improvements. We prospectively analyzed the neurological and clinical outcomes of these patients and compared outcomes pre- and postoperatively. RESULTS: Among 317 cases with the IONM data, we found 29 cases that showed IONM signal improvement compared with baseline. There were 27 cases of compressive myelopathy: 22 had a degenerative cause at the cervical spine, and five, at the thoracic spine. There were two cases of huge neurogenic tumor each at the craniovertebral junction and at the lumbar spine. Both motor-evoked potentials (MEPs) and somatosensory-evoked potentials (SSEPs) signals were improved in six cases, only the MEPs signal improved in 10, and only SSEP signal improved in 13 cases. All cases showed the IONM signal improvement consistently after the decompression procedure during surgery. All patients had a significant improvement in neurological function and subjective symptoms, and none had neurologic deterioration postoperatively. CONCLUSIONS: Improvement of IONM signals during surgery may indicate that no unrecognized neural injury occurred during surgery and a favorable postoperative neurological outcome can be expected.