Does the coronal deformity angular ratio affect bracing outcome in adolescent idiopathic scoliosis?

PURPOSE: To examine if coronal deformity angular ratio (C-DAR) serves as a predictor for progression to surgical magnitude in patients with Adolescent Idiopathic Scoliosis (AIS) treated with thoracolumbar sacral orthosis (TLSO). METHODS: Patients with AIS, prescribed a full-time TLSO, Cobb angle 20-40°, Risser 0-2, who wore the brace ≥ 12.9 h and reached skeletal maturity/surgery were included retrospectively. C-DAR was defined as the Cobb angle divided by the number of vertebrae in the curve, yielding a larger value in short curves. The association between C-DAR and the risk of progression to surgical magnitude (> 45°) was assessed. Secondly, we evaluated the association between pre-treatment Cobb angle and in-brace correction on the risk of progression to > 45°. RESULTS: We included 165 patients with a mean Cobb angle of 30 ± 6°. Of these, 46/165 (28%) progressed ≥ 6° and 26/165 (16%) reached surgical magnitude at the end of treatment. C-DAR was a significant predictor for risk of progression to surgical magnitude with an OR of 1.9 (CI 1.2-2.9) per unit increase in C-DAR. A threshold value of 5.15 was established and demonstrated an OR 5.9 (CI 2.1-17.9) for curve progression to a surgical magnitude. Likewise, pre-treatment Cobb angle showed a significant OR 1.3(CI 1.2-1.4) per degree increase in Cobb, whereas in-brace % correction showed OR 0.96 (CI 0.93-0.98). CONCLUSION: C-DAR is an independent predictor for progression to a surgical magnitude in AIS patients treated with bracing. Patients with a higher C-DAR should be counseled to help set realistic expectations regarding the likelihood of curve progression despite compliance with brace wear.

Pulmonary function in patients with idiopathic scoliosis 40 years after diagnosis.

BACKGROUND CONTEXT: Pulmonary function in patients with scoliosis has been a topic of concern, with some reports of markedly decreased ventilatory function leading to disability and increased mortality in patients with severe scoliosis. Only limited data is available concerning pulmonary function in adult patients with scoliosis. PURPOSE: To report the long-term pulmonary function (PF) in patients diagnosed with idiopathic scoliosis (IS) compared with an age-matched population using extended pulmonary function testing (EPFT). STUDY DESIGN/SETTING: Retrospective clinical follow-up. PATIENT SAMPLE: A total of 177 patients seen at our institution from 1972 to 1983 for a pediatric spinal deformity were assessed for inclusion in the study. About 77/129 eligible patients with IS (60%) partook in a clinical examination including radiographs, and EPFT. OUTCOME MEASURES: The EPFT values included forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC ratio, vital capacity (VC), total lung capacity (TLC), residual volume (RV), RV/TLC ratio, diffusion capacity of carbon monoxide (DLco), carbon monoxide transfer coefficient (KCO) and alveolar volume (VA). Results were expressed with z-scores derived from height and arm span normative data. Z-scores were calculated as z-score=Measured PF-Predicted PF /Relative standard deviation (RSD). The limits of normal, are defined as the 5th and 95th percentile limits (z-score between -1.645 and 1.645), respectively. METHODS: Patients underwent a clinical examination with full spine standing radiographs and EFPT. The results were compared between patients with thoracic and thoracolumbar/lumbar (TL/L) main curves, and overall compared with a background population. Results were expressed with z-scores derived from height and arm span normative data. RESULTS: Of 77 included patients, 76 (99%) were females with a mean age of 54.6±2.5 years. The mean follow-up time was 40.8±2.8 years. Forty-four patients had thoracic main curves, and 33 had TL/L main curves. We found no pulmonary impairment based on z-scores in the total cohort or between groups, with only patients who were current or previous smokers, having z-scores below the normal limits Patients with main thoracic curves displayed significantly lower PF on mean absolute values and mean z-scores on FEV1, FVC, FEV1/FVC ratio, VC, TLC, and DLco compared with main TL/L curves. Patients with thoracic curves had significantly larger Cobb angles at follow-up; 52±17° compared with 40±22° (p-value <.05) in the TL/L group. We found no linear association between thoracic Cobb angle and degree of pulmonary impairment assessed with DLco, TLC, and FVC. Comparison of pulmonary z-scores based on arm span data, differed significantly on FVC and TLC, with the arm span measurements showing lower mean z-scores (p-value <.05). CONCLUSIONS: Using EPFT, no pulmonary impairment could be demonstrated compared to the age-matched population 40 years after a diagnosis of IS. However, patients with thoracic curves had decreased PF compared to patients with TL/L curves although within the normal range. Thus, when treated as current guidelines suggest, patients with idiopathic scoliosis can expect the same long-term pulmonary function as the general population.

Machine learning identifies clusters of the normal adolescent spine based on sagittal balance.

PURPOSE: This study applied a machine learning semi-supervised clustering approach to radiographs of adolescent sagittal spines from a single pediatric institution to identify patterns of sagittal alignment in the normal adolescent spine. We sought to explore the inherent variability found in adolescent sagittal alignment using machine learning to remove bias and determine whether clusters of sagittal alignment exist. METHODS: Multiple semi-supervised machine learning clustering algorithms were applied to 111 normal adolescent sagittal spines. Sagittal parameters for resultant clusters were determined. RESULTS: Machine learning analysis found that the spines did cluster into distinct groups with an optimal number of clusters ranging from 3 to 5. We performed an analysis on both 3 and 5-cluster groups. The 3-cluster groups analysis found good consistency between methods with 96 of 111, while the analysis of 5-cluster groups found consistency with 105 of 111 spines. When assessing for differences in sagittal parameters between the groups for both analyses, there were differences in T4-12 TK, L1-S1 LL, SS, SVA, PI-LL mismatch, and TPA. However, the only parameter that was statistically different for all groups was SVA. CONCLUSIONS: Based on machine learning, the adolescent sagittal spine alignments do cluster into distinct groups. While there were distinguishing features with TK and LL, the most important parameter distinguishing these groups was SVA. Further studies may help to understand these findings in relation to spinal deformities.

The effect of Providence night-time bracing on the sagittal profile in adolescent idiopathic scoliosis.

PURPOSE: Adolescent idiopathic scoliosis (AIS) is characterized by coronal scoliosis and often a sagittal hypokyphosis. The effect of bracing on the sagittal profile is not well understood. The aim of this study is to assess the effect of night-time bracing on the sagittal profile in patients with AIS. METHODS: We retrospectively included AIS patients with a main curve of 25-45° treated with a night-time brace in our institution between 2005 and 2018. Patients with estimated growth potential based on either Risser stage, hand X-rays, or menarchal status were included. Coronal and sagittal radiographic parameters were recorded at both brace- initiation and -termination. Patients were followed until surgery or one year after brace termination. Results were compared to a published cohort of full-time braced patients. RESULTS: One hundred forty-six patients were included. Maximum thoracic kyphosis (TK) increased 2.5° (± 9.7) (p = 0.003), corresponding to a 3.5-fold relative risk increase post bracing in TK compared to a full-time brace cohort. Twenty-seven percent (n = 36) of the patients were hypokyphotic (T4/T12 < 20°) at brace initiation compared with 19% (n = 26) at brace termination (p = 0.134). All other sagittal parameters remained the same at follow-up. We found no association between progression in the coronal plane and change in sagittal parameters. CONCLUSION: This is the first study to indicate that night-time bracing of AIS does not induce hypokyphosis. We found a small increase in TK, with a substantially lower risk of developing flat back deformity compared to full-time bracing. The coronal curve progression was not coupled to a change in TK.

The influence of night-time bracing on curve progression is not affected by curve magnitude in adolescent idiopathic scoliosis: a study of 299 patients.

BACKGROUND AND PURPOSE: The efficacy of bracing larger curves in adolescent idiopathic scoliosis (AIS) patients is uncertain. We aimed to assess the influence of night-time bracing in AIS patients with main curves exceeding 40° Cobb angle at brace initiation. METHODS: We reviewed AIS patients treated with nighttime braces between 2005 and 2018. Patients with curves ≥ 25° and estimated growth potential were included. Patients were monitored with radiographs from brace initiation until brace weaning at skeletal maturity. Patients were grouped based on curve magnitude at initial evaluation: a control group (25-39°) and a large-curves group (≥ 40°). Progression was defined as > 5° increase. RESULTS: We included 299 patients (control group, n = 125; large-curves group, n = 174). In the control group, 65 (52%) patients progressed compared with 101 (58%) in the large-curves group (P = 0.3). The lower-end vertebra (LEV) shifted distally post-bracing in 41 (23%) patients in the largecurves group. Patients with progressive large curves were younger (age 13.2 [SD 1.5] vs. 13.9 [SD 1.1], P = 0.009) and more premenarchal (n = 36 [42%] vs. n = 6 [9%], P < 0.001) compared with non-progressive large curves. CONCLUSION: Progression risk in patients with curves exceeding 40° treated with night-time bracing is similar to smaller curves. The LEV moved distally in almost one-fourth of the larger curves, possibly affecting fusion levels in cases of surgery.

Carbon Instrumentation in Patients with Metastatic Spinal Cord Compression.

Recently carbon spinal implants have been introduced in the treatment of patients with metastatic spinal cord compression (MSCC). This is expected to decrease the deflection of radiation and improve diagnostic imaging and radiotherapy when compared to titanium implants. The aim of this study was to determine the safety and effectiveness of spinal carbon instrumentation (CI) in patients with MSCC in a large cohort study. A total of 163 patients received instrumentation between 1 January 2017 and 31 December 2021. A total of 80 were stabilized with CI and 83 with TI. The outcome measures were surgical revision, postsurgical survival, peri-operative bleeding, and surgery time. The peri-operative blood loss in the CI-group was significantly lower than that in the TI-group: 450mL vs. 630mL, (p = 0.02). There were no significant differences between the groups in mean survival (CI 9.9) vs. (TI 12.9) months (p = 0.39), or the number of patients needing a revision (CI 6) vs. (TI 10), (p = 0.39). The median duration of surgery was 121 min, (p = 0.99) with no significant difference between the two groups. Surgical treatment with CI for MSCC is safe and an equally sufficient treatment when compared to TI.

Postoperative lordosis distribution index, patient reported outcome measures, and revision surgery following transforaminal lumbar interbody fusion.

Objective: Lordosis Distribution Index (LDI) is a new radiographic parameter associated with postoperative residual symptoms in patients undergoing Transforaminal Lumbar Interbody Fusion (TLIF). Recently, it has been applied on patients undergoing instrumented spine surgery, however not correlated to Patient Related Outcome Measures (PROMs). This study investigates whether the obtained the postoperative LDI after TLIF surgery correlates with the clinical outcome measured with PROMs. Methods: This study was based on prospectively obtained data in patients undergoing TLIF throughout 2017 at a Danish university hospital. Medical records and the DaneSpine Database were accessed to obtain preoperative, operative and follow-up data. Primary outcome was Oswestry Disability Index (ODI) 12 months postoperatively. Secondary outcomes included revision rate and additional PROMs. Results: 126 patients were included. 70 patients were classified with normolordosis (56 %), 42 hypolordosis (33 %) and 14 hyperlordosis (11 %). All groups experienced significant radiological changes undergoing surgery. Average reduction in ODI at 12 months postoperatively was -15.3 (±20.0). Minimally clinical important difference was achieved in 68 patients (54.0 %). No significant difference in PROMs between LDI-groups was observed in unadjusted or adjusted analyses. Revision surgery was performed in 8 patients with normolordosis (11.4 %), 7 hypolordosis (16.7 %) and 4 hyperlordosis (28.6 %). Conclusions: We found no significant correlation between postoperative LDI subgroups of normolordotic, hypo- or hyperlordotic patients and the clinical outcome of posterolateral fusion and TLIF surgery. A trend towards lower rate of revision surgery in the normolordotic group compared to the hypo- and hyperlordotic group was observed.

Does Risser stage accurately predict the risk of curve progression in patients with adolescent idiopathic scoliosis treated with night-time bracing?

PURPOSE: Risser stage is widely used as a marker for skeletal maturity (SM) and thereby an indirect measure for the risk of progression of adolescent idiopathic scoliosis (AIS). The Scoliosis Research Society recommends bracing for Risser stages 0-2 as Risser stage 3 or above is considered low risk. Very few studies have assessed the risk of progression during bracing in Risser stages 3-4. The objective of the current study is to determine if Risser stages 3-4 provide a meaningful cutoff in terms of progression risk in patients with AIS treated with night-time bracing. METHODS: AIS patients treated with night-time brace from 2005 to 2018 with a Cobb angle between 25 and 40 degrees and Risser stages 0-4 were retrospectively included. Curve progression (> 5 degrees increase) was monitored until surgery or SM. Skeletal maturity was defined as either 2 years postmenarchal, no height development or closed ulnar epiphyseal plates on radiographs. RESULTS: One hundred and thirty-five patients were included (Risser stages 0-2: n = 86 and 3-4: n = 49). Overall, radiographic curve progression occurred in 52% while progression beyond 45 degrees was seen in 35%. The progression rate in the Risser 0-2 group was 60% and 37% in the Risser 3-4 group (p = 0.012). In multivariate logistic regression analysis, adjusted for Risser stages and age, only premenarchal status showed a statistically significant association with progression (OR: 2.68, 95%CI 1.08-6.67). CONCLUSION: Risser stage does not provide a clinically meaningful differentiation of progression risk in AIS patients treated with a night-time brace. Risk assessment should include other more reliable measures of skeletal growth potential.

Demineralized cortical fibers are associated with a low pseudarthrosis rate in patients undergoing surgery for adult spinal deformity without three-column osteotomy.

Introduction: Following surgical treatment for adult spinal deformity (ASD) there is an increased risk of revision surgery due to mechanical failure or pseudarthrosis. Demineralized cortical fibers (DCF) were introduced at our institution aiming to reduce the risk of pseudarthrosis after ASD surgery. Research question: We wanted to investigate the effect of DCF on postoperative pseudarthrosis compared with allogenic bone graft in ASD surgery without three-column osteotomies (3CO). Materials & Methods: All patients undergoing ASD surgery between January 1, 2010 to June 31, 2020 were included in this interventional study with historical controls. Patients with current or previous 3CO were excluded. Before February 1, 2017, patients undergoing surgery received auto- and allogenic bone graft (non-DCF group) whilst patients after received DCF in addition to autologous bone graft (DCF group). Patients were followed for at least two years. The primary outcome was radiographic or CT-verified postoperative pseudarthrosis requiring revision surgery. Results: We included 50 patients in the DCF group and 85 patients in the non-DCF group for final analysis. Pseudarthrosis requiring revision surgery at two-year follow-up occurred in seven (14%) patients in the DCF group compared with 28 (33%) patients in the non-DCF group (p â€‹= â€‹0.016). The difference was statistically significant, corresponding to a relative risk of 0.43 (95%CI: 0.21-0.94) in favor of the DCF group. Conclusion: We assessed the use of DCF in patients undergoing ASD surgery without 3CO. Our results suggest that the use of DCF was associated with a considerable decreased risk of postoperative pseudarthrosis requiring revision surgery.

The Collateral Effect of Enhanced Recovery After Surgery Protocols on Spine Patients With Neuromuscular Scoliosis.

INTRODUCTION: Enhanced recovery after surgery (ERAS) protocols are often specific to a specific type of surgery without assessing the overall effect on the ward. Previous studies have demonstrated reduced length of stay (LOS) with ERAS protocols in patients with adolescent idiopathic scoliosis (AIS), although the patients are often healthy and with few or no comorbidities. In 2018, we used ERAS principles for patients undergoing AIS surgery with a subsequent 40% reduced LOS. The current study aims to assess the potential collateral effect of LOS in patients surgically treated for neuromuscular scoliosis admitted to the same ward and treated by the same staff but without a standardized ERAS protocol. METHODS: All patients undergoing neuromuscular surgery 2 years before and after ERAS introduction (AIS patients) with a gross motor function classification score of 4 to 5 were included. LOS, intensive care stay, and postoperative complications were recorded. After discharge, all complications leading to readmission and mortality were noted with a minimum of 2 years of follow-up using a nationwide registry. RESULTS: Forty-six patients were included; 20 pre-ERAS and 26 post-ERAS. Cross groups, there were no differences in diagnosis, preoperative curve size, pulmonary or cardiac comorbidities, weight, sex, or age. Postoperative care in the intensive care unit was unchanged between the two groups (1.2 vs 1.1; P = 0.298). When comparing LOS, we found a 41% reduction in the post-ERAS group (11 vs 6.5; P < 0.001) whereas the 90-day readmission rates were without any significant difference (45% vs 34% P = 0.22) We found no difference in the 2-year mortality in either group. CONCLUSION: The employment of ERAS principles in a relatively uncomplicated patient group had a positive, collateral effect on more complex patients treated in the same ward. We believe that training involving the caregiving staff is equally important as pharmacological protocols.

Health-related quality of life in patients 40 years after diagnosis of an idiopathic scoliosis.

AIMS: Only a few studies have investigated the long-term health-related quality of life (HRQoL) in patients with an idiopathic scoliosis. The aim of this study was to investigate the overall HRQoL and employment status of patients with an idiopathic scoliosis 40 years after diagnosis, to compare it with that of the normal population, and to identify possible predictors for a better long-term HRQoL. METHODS: We reviewed the full medical records and radiological reports of patients referred to our hospital with a scoliosis of childhood between April 1972 and April 1982. Of 129 eligible patients with a juvenile or adolescent idiopathic scoliosis, 91 took part in the study (71%). They were evaluated with full-spine radiographs and HRQoL questionnaires and compared with normative data. We compared the HRQoL between observation (n = 27), bracing (n = 46), and surgical treatment (n = 18), and between thoracic and thoracolumbar/lumbar (TL/L) curves. RESULTS: The mean time to follow-up was 40.8 years (SD 2.6) and the mean age of patients was 54.0 years (SD 2.7). Of the 91 patients, 86 were female (95%) and 51 had a main thoracic curve (53%). We found a significantly lower HRQoL measured on all the Scoliosis Research Society 22r instrument (SRS-22r) subdomains (p < 0.001) with the exception of mental health, than in an age-matched normal population. Incapacity to work was more prevalent in scoliosis patients (21%) than in the normal population (11%). The median SRS-22r subscore was 4.0 (interquartile range (IQR) 3.3 to 4.4) for TL/L curves and 4.1 (IQR 3.8 to 4.4) for thoracic curves (p = 0.300). We found a significantly lower self-image score for braced (median 3.6 (IQR 3.0 to 4.0)) and surgically treated patients (median 3.6 (IQR 3.2 to 4.3)) than for those treated by observation (median 4.0 (IQR 4.1 to 4.8); p = 0.010), but no statistically significant differences were found for the remaining subdomains. CONCLUSION: In this long-term follow-up study, we found a significantly decreased HRQoL and capacity to work in patients with an idiopathic scoliosis 40 years after diagnosis.Cite this article: Bone Joint J 2023;105-B(2):166-171.

Prevention of Surgical Site Infections in Spine Surgery: An International Survey of Clinical Practices Among Expert Spine Surgeons.

STUDY DESIGN: Questionnaire-based survey. OBJECTIVES: Surgical site infection (SSI) is a common complication in spine surgery but universal guidelines for SSI prevention are lacking. The objectives of this study are to depict a global status quo on implemented prevention strategies in spine surgery, common themes of practice and determine key areas for future research. METHODS: An 80-item survey was distributed among spine surgeons worldwide via email. The questionnaire was designed and approved by an International Consensus Group on spine SSI. Consensus was defined as more than 60% of participants agreeing to a specific prevention strategy. RESULTS: Four hundred seventy-two surgeons participated in the survey. Screening for Staphylococcus aureus (SA) is not common, whereas preoperative decolonization is performed in almost half of all hospitals. Body mass index (BMI) was not important for surgery planning. In contrast, elevated HbA1c level and hypoalbuminemia were often considered as reasons to postpone surgery. Cefazoline is the common drug for antimicrobial prophylaxis. Alcohol-based chlorhexidine is mainly used for skin disinfection. Double-gloving, wound irrigation, and tissue-conserving surgical techniques are routine in the operating room (OR). Local antibiotic administration is not common. Wound closure techniques and postoperative wound dressing routines vary greatly between the participating institutions. CONCLUSIONS: With this study we provide an international overview on the heterogeneity of SSI prevention strategies in spine surgery. We demonstrated a large heterogeneity for pre-, peri- and postoperative measures to prevent SSI. Our data illustrated the need for developing universal guidelines and for testing areas of controversy in prospective clinical trials.

Complications Following Surgery for Adult Scheuermann's Kyphosis: A 2-Year Follow-Up in 22 Patients.

AIM: To determine the rate of postoperative complications following surgery for Scheuermann?s kyphosis (SK) and ascertain whether restoration to an ideal Roussouly spine type reduced the incidence of postoperative proximal junctional kyphosis (PJK). MATERIAL AND METHODS: We retrospectively screened all patients undergoing SK surgery at our institution (2010?2017) and excluded patients with less than two years of follow-up. Postoperative complications were identified as early or late and minor or major. Successful restoration of Roussouly spine type was assessed and patients were classified as ?restored? or ?non-restored.? Associations between ideal Roussouly restoration and postoperative PJK were evaluated using logistic regression analysis. RESULTS: The study included 22 patients with a median age of 23 (IQR, 20.0?43.8) years. Postoperative complications developed in 17 (77%) of these cases. All 17 patients developed minor complications; seven (32%) patients also exhibited major complications. PJK was diagnosed in 55% of the patients with an 18% overall two-year revision rate. Forty-four percent of the patients in the restored group developed PJK compared to 83% in the non-restored group (p=0.162). Multivariable logistic regression analysis revealed a trend towards an increased incidence of PJK in the non-restored group, albeit without statistical significance (OR, 9.4; 95% CI, 0.7?122.5, p=0.087). CONCLUSION: Our study revealed that 77% of patients undergoing surgery for SK developed at least one complication with a two-year revision rate of 18%. PJK was detected less frequently in patients who were restored to their ideal Roussouly spine type, although this finding did not achieve statistical significance.

Is preoperative S-albumin associated to postoperative complications and readmission in patients with adult spinal deformity: a prospective analysis of 128 patients using the Spine AdVerse Event Severity (SAVES) system.

PURPOSE: To assess the association between preoperative S-albumin and postoperative outcome following adult spinal deformity (ASD) surgery. METHODS: All patients undergoing ASD surgery from February 1, 2017 and January 31, 2018 at a single quaternary referral center were prospectively included. Adverse events (AE) during admission were assessed using the Spine AdVerse Events Severity (SAVES) system. Based on preoperative S-albumin, patients were categorized as "normal" or "abnormal" and compared regarding postoperative outcome, adverse events (AEs), 30- and 90-day readmission, revision surgery, and mortality. RESULTS: A total of 128 patients aged ≥ 18 years were included, and S-albumin was available in 88%. Of these, 73% (n = 93) were classified as "normal", 16% (n = 20) as "abnormal", and 12% (n = 15) as "missing". The "normal" albumin group had less comorbidity burden [ASA score 2 (2, 3) vs 3 (2, 3), p = 0.011], higher hemoglobin levels (8.4 (± 0.9) mmol/L vs 7.4 (± 1.1) mmol/L, p < 0.001), and higher S-albumin (38.9 (± 2.7) g/L vs 31.9 (± 4.4) g/L, < 0.001). The rate of 90-day readmission was significantly increased in the "abnormal" group (65% vs 36%), corresponding to a relative risk increase of 1.25 (95% CI 1.02-1.52, p = 0.029). Similar increased risks were found in subsequent logistic regression analyses, although results were not significant in multivariable analysis (p = 0.102). Comparing remaining outcome parameters, point estimates revealed increased AEs, 30-day readmission, and revision in the "abnormal" albumin group, although effects did not reach statistical significance. CONCLUSIONS: In a prospective, consecutive, single-center cohort of 128 patients undergoing ASD surgery, we found a significant association between "abnormal" preoperative S-albumin and increased 90-day readmission. Furthermore, although the findings were not statistically significant, we did find that AEs, 30-day readmission, and revision were numerically more frequent in the "abnormal" group, suggesting an expected tendency that should be further investigated. We conclude that nutritional status prior to ASD surgery could be important to consider and suggest validation in larger prospective cohorts. LEVEL OF EVIDENCE: Prognostic II.

Use of demineralized cortical fibers is associated with reduced risk of pseudarthrosis after pedicle subtraction osteotomy for adult spinal deformity.

PURPOSE: To assess the effect of demineralized cortical fibers (DCF) on postoperative pseudarthrosis requiring revision surgery in patients undergoing pedicle subtraction osteotomy (PSO) for adult spinal deformity (ASD). METHODS: The use of DCF was introduced across all procedures in 2017 and subsequent patients undergoing PSO surgery were prospectively and consecutively registered. Following sample-size estimation, a retrospective cohort was also registered undergoing the same procedure immediately prior to the implementation of DCF. The non-DCF group underwent surgery with ABG. Minimum follow-up was 2 years in both groups. The main outcome was postoperative pseudarthrosis, either CT-verified or verified intraoperatively during revision surgery due to rod breakage and assessed using Kaplan-Meier survival analyses. RESULTS: A total of 48 patients were included in the DCF group and 76 in the non-DCF group. The DCF group had more frequently undergone previous spine surgery (60% vs 36%) and had shorter follow-up (32 ± 2 vs 40 ± 7 months). Pseudarthrosis occurred in 7 (15%) patients in the DCF group and 31 (41%) in the non-DCF group, corresponding to a relative risk increase of 2.6 (95%CI 1.3-2.4, P < 0.01). 1-KM survival analyses, taking time to event into account and thus the difference in follow-up, also showed increased pseudarthrosis in the non-DCF group (log-rank P = 0.022). Similarly, multivariate logistic regression adjusted for age, instrumented levels and sacral fusion was also with significantly increased odds of pseudarthrosis in the non-DCF group (OR: 4.3, 95%CI: 1.7-11.3, P < 0.01). CONCLUSION: We found considerable and significant reductions in pseudarthrosis following PSO surgery with DCF compared to non-DCF. LEVEL OF EVIDENCE: III.

Rapid Discharge Protocol Reduces Length of Stay and Eliminates Postoperative Nausea and Vomiting After Surgery for Adolescent Idiopathic Scoliosis.

BACKGROUND: Implementing standardized pathways following adolescent idiopathic scoliosis surgery have been shown to reduce length of stay (LOS). However, controversies still exist. This applies especially to the transition to solid foods, postoperative pruritus, and postoperative nausea and vomiting (PONV). The aim of this proposed protocol is to present an option to reduce these factors while reducing the LOS. METHODS: The protocol was designed with reduction of morphine. One-hundred and eight patients were included in this study, including 66 controls before intervention. All patients underwent posterior scoliosis surgery. All patients were scored daily using a numeric rating scale, and they noted if any nausea, vomiting, or pruritus was present. All medications were recorded. For every 20 patients included, the steering committee met to identify any implementation issues. RESULTS: LOS was reduced from 6.3 to 3.6 days (43% reduction, P = 0.003). PONV was reduced from affecting 82% to 9% of patients (P < 0.0001). The number of patients experiencing postoperative pruritus was reduced from 40% to 2% (P < 0.001). Time spent in postoperative recovery was reduced from 278 (117 - 470) minutes to 199 (128 - 643), P < 0.001. Patients' pain scores remained unchanged compared with controls (mean 4 [3 - 8]). We found no adverse effects of solid food intake from postoperative day 0. CONCLUSIONS: We found a significant reduction in length of stay, PONV, and pruritus after implementation of the protocol. This allowed for no restrictions in regards to solid food intake postoperatively.

Lordosis Distribution Index in Short-Segment Lumbar Spine Fusion - Can Ideal Lordosis Reduce Revision Surgery and Iatrogenic Deformity?

OBJECTIVE: The demand for spinal fusion is increasing, with concurrent reports of iatrogenic adult spinal deformity (flatback deformity) possibly due to inappropriate lordosis distribution. This distribution is assessed using the lordosis distribution index (LDI) which describes the upper and lower arc lordosis ratio. Maldistributed LDI has been associated to adjacent segment disease following interbody fusion, although correlation to later-stage deformity is yet to be assessed. We therefore aimed to investigate if hypolordotic lordosis maldistribution was associated to radiographic deformity-surrogates or revision surgery following instrumented lumbar fusion. METHODS: All patients undergoing fusion surgery ( ≤ 4 vertebra) for degenerative lumbar diseases were retrospectively included at a single center. Patients were categorized according to their postoperative LDI as: "normal" (LDI 50-80), "hypolordotic" (LDI < 50), or "hyperlordotic" (LDI > 80). RESULTS: We included 149 patients who were followed for 21 ± 14 months. Most attained a normally distributed lordosis (62%). The hypolordotic group had increased postoperative pelvic tilt (PT) (p < 0.001), pelvic incidence minus lumbar lordosis (PI-LL) mismatch (p < 0.001) and decreased global lordosis (p = 0.007) compared to the normal group. Survival analyses revealed a significant difference in revision surgery (p = 0.03), and subsequent multivariable logistic regression showed increased odds of 1-year revision in the hypolordotic group (p = 0.04). There was also a negative, linear correlation between preoperative pelvic incidence (PI) and postoperative LDI (p < 0.001). CONCLUSION: In patients undergoing instrumented lumbar fusion surgery, hypolordotic lordosis maldistribution (LDI < 50) was associated to increased risk of revision surgery, increased postoperative PT and PI-LL mismatch. Lordosis distribution should be considered prior to spinal fusion, especially in high PI patients.

[Treatment of metastatic spinal cord compression].

Metastatic spinal cord compression is an oncologic emergency, and the most frequent initial symptom is radicular backpain. Urgent diagnostics with acute MRI and early treatment is essential to prevent permanent neurologic damage. Treatment is mainly palliative. For patients who have a good prognosis, the treatment of choice is decompressive surgery followed by radiotherapy, but only few patients are candidates to surgery due to significant comorbidities and poor performance status. Optimal therapy is required to maintain high quality of life at an acceptable risk, as argued in this review.

[Spinefractures - diagnosis and treatment].

Acute onset back pain is a common reason for referral to primary health care or emergency departments. In this review, the different spine fracture types are highlighted, and a treatment algorithm is proposed. CT is the modality of choice when a spine fracture is suspected. MRI should be performed when disc or ligamentous lesions are suspected or in patients with known ankylosis or diffuse idiopathic skeletal hyperostosis. Treatment is mainly conservative with bracing, but unstable fractures and patients with neurological deficits should be treated surgically.

A Comparison of Mortality and Morbidity Between Complex and Degenerative Spine Surgery in Prospectively Collected Data From 2,280 Procedures.

OBJECTIVE: The reported incidence of complications and/or adverse events (AEs) following spine surgery varies greatly. A validated, systematic, reproducible reporting system to quantify AEs was used in 2 prospective cohorts, from 2 spine surgery centers, conducting either complex or purely degenerative spine surgery; in a comparative fashion. The aim was to highlight the differences between 2 distinctly different prospective cohorts with patients from the same background population. METHODS: AEs were registered according to the predefined AE variables in the SAVES (Spine AdVerse Events Severity) system which was used to record all intra- and perioperative AEs. Additional outcomes, including mortality, length of stay, wound infection requiring revision, readmission, and unplanned revision surgery during the index admission, were also registered. RESULTS: A total of 593 complex and 1,687 degenerative procedures were consecutively included with 100% data completion. There was a significant difference in morbidity when comparing the total number of AEs between the 2 groups (p < 0.001): with a mean number of 1.42 AEs per patient (n = 845) in the complex cohort, and 0.97 AEs per patient (n = 1,630) in the degenerative cohort. CONCLUSION: In this prospective study comparing 2 cohorts, we report the rates of AEs related to spine surgery using a validated reproducible grading system for registration. The rates of morbidity and mortality were significantly higher following complex spine surgery compared to surgery for degenerative spine disease.