An international validation of the AO spine subaxial injury classification system

Purpose

To validate the AO Spine Subaxial Injury Classification System with participants of various experience levels, subspecialties, and geographic regions.

Methods

A live webinar was organized in 2020 for validation of the AO Spine Subaxial Injury Classification System. The validation consisted of 41 unique subaxial cervical spine injuries with associated computed tomography scans and key images. Intraobserver reproducibility and interobserver reliability of the AO Spine Subaxial Injury Classification System were calculated for injury morphology, injury subtype, and facet injury. The reliability and reproducibility of the classification system were categorized as slight (ƙ = 0–0.20), fair (ƙ = 0.21–0.40), moderate (ƙ = 0.41–0.60), substantial (ƙ = 0.61–0.80), or excellent (ƙ = > 0.80) as determined by the Landis and Koch classification.

Results

A total of 203 AO Spine members participated in the AO Spine Subaxial Injury Classification System validation. The percent of participants accurately classifying each injury was over 90% for fracture morphology and fracture subtype on both assessments. The interobserver reliability for fracture morphology was excellent (ƙ = 0.87), while fracture subtype (ƙ = 0.80) and facet injury were substantial (ƙ = 0.74). The intraobserver reproducibility for fracture morphology and subtype were excellent (ƙ = 0.85, 0.88, respectively), while reproducibility for facet injuries was substantial (ƙ = 0.76).

Conclusion

The AO Spine Subaxial Injury Classification System demonstrated excellent interobserver reliability and intraobserver reproducibility for fracture morphology, substantial reliability and reproducibility for facet injuries, and excellent reproducibility with substantial reliability for injury subtype.

     

AO Spine upper cervical injury classification system: a description and reliability study

Background ContextPrior upper cervical spine injury classification systems have focused on injuries to the craniocervical junction (CCJ), atlas, and dens independently. However, no previous system has classified upper cervical spine injuries using a comprehensive system incorporating all injuries from the occiput to the C2–3 joint.PurposeTo (1) determine the accuracy of experts at correctly classifying upper cervical spine injuries based on the recently proposed AO Spine Upper Cervical Injury Classification System (2) to determine their interobserver reliability and (3) identify the intraobserver reproducibility of the experts.Study Design/SettingInternational Multi-Center Survey.Patient SampleA survey of international spine surgeons on 29 unique upper cervical spine injuries.Outcome MeasuresClassification accuracy, interobserver reliability, intraobserver reproducibility.MethodsThirteen international AO Spine Knowledge Forum Trauma members participated in two live webinar-based classifications of 29 upper cervical spine injuries presented in random order, four weeks apart. Percent agreement with the gold-standard and kappa coefficients (?) were calculated to determine the interobserver reliability and intraobserver reproducibility.ResultsRaters demonstrated 80.8% and 82.7% accuracy with identification of the injury classification (combined location and type) on the first and second assessment, respectively. Injury classification intraobserver reproducibility was excellent (mean, [range] ?=0.82 [0.58-1.00]). Excellent interobserver reliability was found for injury location (? = 0.922 and ?=0.912) on both assessments, while injury type was substantial (?=0.689 and 0.699) on both assessments. This correlated to a substantial overall interobserver reliability (?=0.729 and 0.732).ConclusioNSEarly phase validation demonstrated classification of upper cervical spine injuries using the AO Spine Upper Cervical Injury Classification System to be accurate, reliable, and reproducible. Greater than 80% accuracy was detected for injury classification. The intraobserver reproducibility was excellent, while the interobserver reliability was substantial.     

Reliability assessment of AOSpine thoracolumbar spine injury classification system and Thoracolumbar Injury Classification and Severity Score (TLICS) for thoracolumbar spine injuries: results of a multicentre study

Purpose

The aim of this multicentre study was to determine whether the recently introduced AOSpine Classification and Injury Severity System has better interrater and intrarater reliability than the already existing Thoracolumbar Injury Classification and Severity Score (TLICS) for thoracolumbar spine injuries.

Methods

Clinical and radiological data of 50 consecutive patients admitted at a single centre with a diagnosis of an acute traumatic thoracolumbar spine injury were distributed to eleven attending spine surgeons from six different institutions in the form of PowerPoint presentation, who classified them according to both classifications. After time span of 6 weeks, cases were randomly rearranged and sent again to same surgeons for re-classification. Interobserver and intraobserver reliability for each component of TLICS and new AOSpine classification were evaluated using Fleiss Kappa coefficient (k value) and Spearman rank order correlation.

Results

Moderate interrater and intrarater reliability was seen for grading fracture type and integrity of posterior ligamentous complex (Fracture type: k = 0.43 ± 0.01 and 0.59 ± 0.16, respectively, PLC: k = 0.47 ± 0.01 and 0.55 ± 0.15, respectively), and fair to moderate reliability (k = 0.29 ± 0.01 interobserver and 0.44+/0.10 intraobserver, respectively) for total score according to TLICS. Moderate interrater (k = 0.59 ± 0.01) and substantial intrarater reliability (k = 0.68 ± 0.13) was seen for grading fracture type regardless of subtype according to AOSpine classification. Near perfect interrater and intrarater agreement was seen concerning neurological status for both the classification systems.

Conclusions

Recently proposed AOSpine classification has better reliability for identifying fracture morphology than the existing TLICS. Additional studies are clearly necessary concerning the application of these classification systems across multiple physicians at different level of training and trauma centers to evaluate not only their reliability and reproducibility, but also the other attributes, especially the clinical significance of a good classification system.

     

Reliability analysis of the AOSpine thoracolumbar spine injury classification system by a worldwide group of naïve spinal surgeons

Purpose

The aims of this study were (1) to demonstrate the AOSpine thoracolumbar spine injury classification system can be reliably applied by an international group of surgeons and (2) to delineate those injury types which are difficult for spine surgeons to classify reliably.

Methods

A previously described classification system of thoracolumbar injuries which consists of a morphologic classification of the fracture, a grading system for the neurologic status and relevant patient-specific modifiers was applied to 25 cases by 100 spinal surgeons from across the world twice independently, in grading sessions 1 month apart. The results were analyzed for classification reliability using the Kappa coefficient (κ).

Results

The overall Kappa coefficient for all cases was 0.56, which represents moderate reliability. Kappa values describing interobserver agreement were 0.80 for type A injuries, 0.68 for type B injuries and 0.72 for type C injuries, all representing substantial reliability. The lowest level of agreement for specific subtypes was for fracture subtype A4 (Kappa = 0.19). Intraobserver analysis demonstrated overall average Kappa statistic for subtype grading of 0.68 also representing substantial reproducibility.

Conclusion

In a worldwide sample of spinal surgeons without previous exposure to the recently described AOSpine Thoracolumbar Spine Injury Classification System, we demonstrated moderate interobserver and substantial intraobserver reliability. These results suggest that most spine surgeons can reliably apply this system to spine trauma patients as or more reliably than previously described systems.

     

Reliability and reproducibility analysis of the AOSpine Sacral Fractures Classification System by spinal and pelvic surgeons

Study DesignRetrospective Cohort StudyObjectivesThe AOSpine Sacral Classification System was proposed as a comprehensive and universally accepted new classification for Sacral Fractures, and was recently internally validated. However, an external, independent and multidisciplinary reports on validation of this classification is lacking. Aim of the present study is to analyze the interobserver reliability and intraobserver reproducibility of the AOSpine Sacral Classification System for Sacral Fractures between orthopedic spinal and pelvic surgeons with different levels of experience.MethodsOur institutional database was searched to retrieve patients with acute, traumatic sacral injury admitted from June 2017 to June 2020. For each patients, X-Rays and CT scans were collected. Three Orthopedic Pelvic Surgeons (Group A) and three Spine Surgeons (Group B), with different level of experience (Junior, 〈 5 years; Middle, 5–10 years; Expert 〉 10 years) independently classified all the sacral fractures included in the dataset, with two separate evaluation three weeks apart. Both intra and interobserver reliability were calculated with k-coefficient.ResultsOverall, 150 patients were included in the final dataset, for a total of 1800 different assessments, with all the subtypes reported. The intraobserver reproducibility for the whole group was substantial (κ=0.72). Overall, the interobserver reliability was moderate, with a κ=0.57. When only fracture type was taken in account, the κ value became substantial (κ=0.62). No significant differences were found comparing group A and group B (0.55 vs κ 0.55, p>0.05). No significant differences according to surgeon's experience were found; however, the κ value was slightly lower among the junior surgeons.ConclusionsOur findings confirmed the reliability and reproducibility of this classification in clinical practice. In the current study the surgeon's expertise (pelvic and spinal trauma) and the level of experience does not influence the reliability of the classification system.     

Percutaneous dorsal instrumentation for thoracolumbar extension-distraction fractures in patients with ankylosing spinal disorders: a case series

Background contextThoracolumbar extension-distraction fractures are rare injuries mainly restricted to patients suffering from ankylosing spinal disorders. The most appropriate surgical treatment of these unstable spinal injuries remains to be clarified.PurposeTo report on a cohort of 10 patients treated with closed reduction and percutaneous dorsal instrumentation.Study designCase series.Patient sampleTen consecutive patients with ankylosing spinal disorders and thoracolumbar extension-distraction fractures (Type B3 according to the AOSpine Thoracolumbar Spine Injury Classification System).Outcome measuresPostoperative reduction, alignment, and implant position were analyzed by computed tomography. Loss of reduction was assessed on lateral radiographs by using the Cobb technique. Ambulation ability and pain were assessed at follow-up.MethodsMinimally invasive dorsal percutaneous instrumentation was performed in 10 consecutive patients (3 men, 7 women) with a mean age of 81.5 (range 72–90) years between May 2010 and December 2012. The mean postoperative follow-up time was 7.9 (range 4–28) months.ResultsAll 10 patients were treated with closed reduction and dorsal instrumentation; in no case was conversion to an open approach required. The mean operation time was 60.2 (range 32–135) minutes. None of the patients presented neurologic deficits. Cement-augmented screws were implanted in two cases. Sufficient radiographic correction was achieved in all patients; no case of loss of reduction was noted at final follow-up. In one case, complete hardware removal was performed 9 months after the index operation because of persistent back pain at the level of the implant. One patient died of postoperative inferior vena cava obstruction. At discharge, all patients were able to ambulate without the need for crutches or opioid analgesics. At final follow-up, all patients ambulated with full weight bearing; four patients reported persistent back pain.ConclusionsIn fragile patients with ankylosing spinal disorders and thoracolumbar extension-distraction fractures, closed reduction and percutaneous dorsal instrumentation provide a satisfying midterm functional outcome while minimizing perioperative risks compared with conventional dorsoventral procedures.     

The AO spine upper cervical injury classification system: Do work setting or trauma center affiliation affect classification accuracy or reliability?

PurposeTo assess the accuracy and reliability of the AO Spine Upper Cervical Injury Classification System based on a surgeons’ work setting and trauma center affiliation.MethodsA total of 275 AO Spine members participated in a validation of 25 upper cervical spine injuries, which were evaluated by computed tomography (CT) scans. Each participant was grouped based on their work setting (academic, hospital-employed, or private practice) and their trauma center affiliation (Level I, Level II or III, and Level IV or no trauma center). The classification accuracy was calculated as percent of correct classifications, while interobserver reliability, and intraobserver reproducibility were evaluated based on Fleiss’ Kappa coefficient.ResultsThe overall classification accuracy for surgeons affiliated with a level I trauma center was significantly greater than participants affiliated with a level II/III center or a level IV/no trauma center on assessment one (p₁<0.0001) and two (p₂ = 0.0003). On both assessments, surgeons affiliated with a level I or a level II/III trauma center were significantly more accurate at identifying IIIB injury types (p₁ = 0.0007; p₂ = 0.0064). Academic surgeons and hospital employed surgeons were significantly more likely to correctly classify type IIIB injuries on assessment one (p₁ = 0.0146) and two (p₂ = 0.0015). When evaluating classification reliability, the largest differences between work settings and trauma center affiliations was identified in type IIIB injuries.ConclusionType B injuries are the most difficult injury type to correctly classify. They are classified with greater reliability and classification accuracy when evaluated by academic surgeons, hospital-employed surgeons, and surgeons associated with higher-level trauma centers (I or II/III).     

Do 3-D Printed Handheld Models Improve Surgeon Reliability for Recognition of Intraarticular Distal Radius Fracture Characteristics?

BackgroundFor fracture care, radiographs and two-dimensional (2-D) and three-dimensional (3-D) CT are primarily used for preoperative planning and postoperative evaluation. Intraarticular distal radius fractures are technically challenging to treat, and meticulous preoperative planning is paramount to improve the patient’s outcome. Three-dimensionally printed handheld models might improve the surgeon’s interpretation of specific fracture characteristics and patterns preoperatively and could therefore be clinically valuable; however, the additional value of 3-D printed handheld models for fractures of the distal radius, a high-volume and commonly complex fracture due to its intraarticular configuration, has yet to be determined.Questions/purposes(1) Does the reliability of assessing specific fracture characteristics that guide surgical decision-making for distal radius fractures improve with 3-D printed handheld models? (2) Does surgeon agreement on the overall fracture classification improve with 3-D printed handheld models? (3) Does the surgeon’s confidence improve when assessing the overall fracture configuration with an additional 3-D model?MethodsWe consecutively included 20 intraarticular distal radius fractures treated at a Level 1 trauma center between May 2018 and November 2018. Ten surgeons evaluated the presence or absence of specific fracture characteristics (volar rim fracture, die punch, volar lunate facet, dorsal comminution, step-off > 2 mm, and gap > 2 mm), fracture classification according to the AO/Orthopaedic Trauma Association (OTA) classification scheme, and their confidence in assessing the overall fracture according to the classification scheme, rated on a scale from 0 to 10 (0 = not at all confident to 10 = very confident). Of 10 participants regularly treating distal radius fractures, seven were orthopaedic trauma surgeons and three upper limb surgeons with experience levels ranging from 1 to 25 years after completion of residency training. Fractures were assessed twice, with 1 month between each assessment. Initially, fractures were assessed using radiographs and 2-D and 3-D CT images (conventional assessment); the second time, the evaluation was based on radiographs and 2-D and 3-D CT images with an additional 3-D handheld model (3-D printed handheld model assessment). On both occasions, fracture characteristics were evaluated upon a surgeon’s own interpretation, without specific instruction before assessment. We provided a sheet demonstrating the AO/OTA classification scheme before evaluation on each session. Multi-rater Fleiss’s kappa was used to determine intersurgeon reliability for assessing fracture characteristics and classification. Confidence regarding assessment of the overall fracture classification was assessed using a paired t-test.ResultsWe found that 3-D printed models of intraarticular distal radius fractures led to no change in kappa values for the reliability of all characteristics: volar rim (conventional kappa 0.19 [95% CI 0.06 to 0.32], kappa for 3-D handheld model 0.23 [95% CI 0.11 to 0.36], difference of kappas 0.04 [95% CI -0.14 to 0.22]; p = 0.66), die punch (conventional kappa 0.38 [95% CI 0.15 to 0.61], kappa for 3-D handheld model 0.50 [95% CI 0.23 to 0.78], difference of kappas 0.12 [95% CI -0.23 to 0.47]; p = 0.52), volar lunate facet (conventional kappa 0.31 [95% CI 0.14 to 0.49], kappa for 3-D handheld model 0.48 [95% CI 0.23 to 0.72], difference of kappas 0.17 [95% CI -0.12 to 0.46]; p = 0.26), dorsal comminution (conventional kappa 0.36 [95% CI 0.13 to 0.58], kappa for 3-D handheld model 0.31 [95% CI 0.11 to 0.51], difference of kappas -0.05 [95% CI -0.34 to 0.24]; p = 0.74), step-off > 2 mm (conventional kappa 0.55 [95% CI 0.29 to 0.82], kappa for 3-D handheld model 0.58 [95% CI 0.31 to 0.85], difference of kappas 0.03 [95% CI -0.34 to 0.40]; p = 0.87), gap > 2 mm (conventional kappa 0.59 [95% CI 0.39 to 0.79], kappa for 3-D handheld model 0.69 [95% CI 0.50 to 0.89], difference of kappas 0.10 [95% CI -0.17 to 0.37]; p = 0.48). Although there appeared to be categorical improvement in kappa values for some fracture characteristics, overlapping CIs indicated no change. Fracture classification did not improve (conventional diagnostics: kappa 0.27 [95% CI 0.14 to 0.39], conventional diagnostics with an additional 3-D handheld model: kappa 0.25 [95% CI 0.15 to 0.35], difference of kappas: -0.02 [95% CI -0.18 to 0.14]; p = 0.81). There was no improvement in self-assessed confidence in terms of assessment of overall fracture configuration when a 3-D model was added to the evaluation process (conventional diagnostics 7.8 [SD 0.79 {95% CI 7.2 to 8.3}], 3-D handheld model 8.5 [SD 0.71 {95% CI 8.0 to 9.0}], difference of score: 0.7 [95% CI -1.69 to 0.16], p = 0.09).ConclusionsIntersurgeon reliability for evaluating the characteristics of and classifying intraarticular distal radius fractures did not improve with an additional 3-D model. Further studies should evaluate the added value of 3-D printed handheld models for teaching surgical residents and medical trainees to define the future role of 3-D printing in caring for fractures of the distal radius.Level of EvidenceLevel II, diagnostic study.     

Inter-rater reliability of the Quebec Task Force classification system for recent-onset Whiplash Associated Disorders

PurposeThe inter-rater reliability of the Quebec Task Force (QTF) classification system for Whiplash-Associated Disorders (WAD) remains unknown. Our objective was to determine the inter-rater reliability of the WAD classification between an experienced chiropractic clinician and two chiropractic residents.MethodsWe conducted an inter-rater reliability study using baseline clinical data from 80 participants assessed for inclusion in a randomized clinical trial of the conservative management of WAD grades I and II. We reported reliability using Cohen’s kappa (k) and 95% confidence intervals (CI).ResultsThe mean duration of WAD symptoms was 7.6 days (s.d.=5.2). In our study, the interrater reliability of the WAD grade classification varied from k=0.04 (95% CI -0.04 to 0.12) to k=0.80 (95% CI 0.67 to 0.94).ConclusionInter-rater reliability of the WAD classification varied greatly across raters and may be associated with the experience of the raters and with their understanding of the criteria. Our results suggest that clinicians may benefit from training to standardize how they classify WAD. Furthermore, our results need to be tested in a different sample of patients and with a range of clinicians from different clinical disciplines.     

A new way to use transit-time flow measurement for coronary artery bypass grafting

 Open in a separate windowOBJECTIVESTransit-time flow measurement is a recognized method for graft evaluation in coronary surgery. However, single flow measurement has been associated with a low specificity for detecting graft dysfunction. The goal of this study was to assess the value of transit-time flow measurement for assessing in situ internal mammary artery grafts during non-existent native coronary circulation and the relevance of collateral blood flow in target vessels.METHODSBetween 2014 and 2018, a total of 134 patients undergoing on-pump coronary artery bypass grafting were evaluated using transit-time flow measurement. We analysed 111 single left internal mammary artery and 57 single right internal mammary artery bypasses. Correlations between coronary relevant parameters were calculated using Spearman’s ρ coefficient. Risk factors for decreased flow with an arrested heart (FAH) <30 ml/min and an increased pulsatility index (PI) >3.0 as well as flow reduction >30% were calculated.RESULTSFAH correlated with the diameter of the target vessel (Spearman’s ρ = 0.32; P < 0.001), the amount of blood distribution (Spearman’s ρ = 0.34; P < 0.001), the PI (Spearman’s ρ = 0.19; P = 0.019) and the degree of stenosis (Spearman’s ρ = −0.17; P = 0.042). The percentage of flow change was found to correlate with the PI (Spearman’s ρ = −0.47; P < 0.0001), the degree of stenosis (Spearman’s ρ = 0.42; P < 0.001), the diameter of the target vessel (Spearman’s ρ = −0.22; P = 0.008) and the area of blood distribution (Spearman’s ρ = −0.19; P = 0.018). A small blood distribution area was the only risk factor for decreased FAH [odds ratio (OR) 8.43, confidence interval (CI) 95% (3.04–23.41); P < 0.001]. Binary logistic regression identified PI [OR 2.05, CI 95% (1.36–3.10); P = 0.001], FAH [OR 0.98, CI 95% (0.97–0.99); P = 0.005] and degree of stenosis [OR 0.95, CI 95% (0.92–0.99); P = 0.011] as risk factors for decreased flow after cardiopulmonary bypass (<30 ml/min). An increased PI (>3) was mainly influenced by percentage of flow change [OR 0.99, CI 95% (0.98–1.00); P = 0.031].CONCLUSIONSFAH and percentage of flow change are related to the dimensions of the target vessel and the degree of stenosis. The addition of flow measurements with the heart arrested provides additional information about the bypass graft, the quality of the anastomosis and the physiology of the coronary circulation.     

Efficacy and safety of expanded hemodialysis in hemodialysis patients: a meta-analysis and systematic review

BackgroundExpanded hemodialysis (HDx) is a new dialysis modality, but a systematic review of the clinical effects of using HDx is lacking. This systematic review and meta-analysis aimed to assess the efficacy and safety of HDx for hemodialysis (HD) patients.MethodsPubMed, the Cochrane library, and EMBASE databases were systematically searched for prospective interventional studies comparing the efficacy and safety of HDx with those of high flux HD or HDF in HD patients.ResultsEighteen trials including a total of 853 HD patients were enrolled. HDx increased the reduction ratio (RR) of β2-microglobulin (SMD 6.28%, 95% CI 0.83, 1.73, p = .02), κFLC (SMD 15.86%, 95% CI 6.96, 24.76, p = .0005), and λFLC (SMD 22.42%, 95% CI, 17.95, 26.88, p < .0001) compared with high flux HD. The RR of β2-microglobulin in the HDx group was lower than that in the HDF group (SMD −3.53%, 95% CI −1.16, −1.9, p < .0001). HDx increased the RRs of κFLC (SMD 1.34%, 95% CI 0.52, 2.16, p = .001) and λFLC (SMD 7.28%, 95% CI 1.08, 13.48, p = .02) compared to HDF. There was no significant difference in albumin loss into the dialysate between the HDx and HDF groups (SMD 0.35 g/session, 95% CI −2.38, 3.09, p = .8).ConclusionsThis meta-analysis indicated that compared with high-flux HD and HDF, HDx can increase the clearance of medium and large-molecular-weight uremic toxins. And it does not increase the loss of albumin compared with HDF.     

The Ghent Global IAD Monitoring Tool (GLOBIAD‐M) to monitor the healing of incontinence‐associated dermatitis (IAD): Design and reliability study

The aim of this study was to design and evaluate the reliability of the Ghent Global incontinence‐associated dermatitis (IAD) Monitoring Tool (GLOBIAD‐M). The tool was designed based on the internationally validated Ghent Global IAD Categorisation Tool (GLOBIAD). After designing and validation by experts, one trained researcher carried out 36 observations of 9 patients affected with IAD. Photographs of the IAD lesions were independently assessed by a second trained researcher. Measures for inter‐rater agreement (p _o ) and reliability [Cohen''s Kappa (ĸ) and intra‐class correlation coefficients (ICC)] were analysed. The p _o ranged between 0.86 for the item ‘maceration’ and 0.97 for the item ‘clinical signs of infection’. The ĸ for the item ‘GLOBIAD classification’ was 0.61 [95% confidence interval (CI) 0.28‐0.95] and 0.72 (95% CI 0.50‐0.95) for ‘maceration’. The lowest ĸ was found for the item ‘oedema’ (0.27; 95% CI −0.24‐0.79). The ICC of the item ‘redness’ was 0.83 (95% CI 0.69‐0.91) and 0.87 (95% CI 0.76‐0.93) for ‘skin loss’. The inter‐rater agreement and reliability of the GLOBIAD‐M appears to be good for the assessment of photographs by experts. This tool could support clinical decision‐making for IAD treatment. Further validation with clinicians is, however, needed.     

Altered kidney function induced by SARS-CoV-2 infection and acute kidney damage markers predict survival outcomes of COVID-19 patients: a prospective pilot study

BackgroundLiterature with regard to coronavirus disease 2019 (COVID-19) associated morbidities and the risk factors for death are still emerging. In this study, we investigated the presence of kidney damage markers and their predictive value for survival among hospitalized subjects with COVID-19.MethodsForty-seven participants was included and grouped as: ‘COVID-19 patients before treatment’, ‘COVID-19 patients after treatment’, ‘COVID-19 patients under treatment in intensive care unit (ICU)’, and ‘controls’. Kidney function tests and several kidney injury biomarkers were compared between the groups. Cumulative rates of death from COVID-19 were determined using the Kaplan–Meier method. The associations between covariates including kidney injury markers and death from COVID-19 were examined, as well.ResultsSerum creatinine and cystatin C levels, urine Kidney Injury Molecule-1 (KIM-1)/creatinine ratio, and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), CKD-EPI cystatin C, and CKD-EPI creatinine–cystatin C levels demonstrated significant difference among the groups. The most significant difference was noted between the groups ‘COVID-19 patients before treatment’ and ‘COVID-19 patients under treatment in ICU’. Advancing age, proteinuria, elevated serum cystatin C, and urine KIM-1/creatinine ratio were all significant univariate correlates of death (p < 0.05, for all). However, only elevated urine KIM-1/creatinine ratio retained significance in an age, sex, and comorbidities adjusted multivariable Cox regression (OR 6.11; 95% CI: 1.22–30.53; p = 0.02), whereas serum cystatin C showing only a statistically non-significant trend (OR 1.42; 95% CI: 0.00–2.52; p = 0.09).ConclusionsOur findings clearly demonstrated the acute kidney injury related to COVID-19. Moreover, urine KIM-1/creatinine ratio was associated with COVID-19 specific death.     

Prognostic implications of predialysis patients’ symptoms in peritoneal dialysis patients

BackgroundAs kidney disease progresses, patients often experience a variety of symptoms. There are very few studies reporting spectrum of predialysis patients’ symptoms in peritoneal dialysis (PD) patients. Furthermore, the clinical significance of predialysis patients’ symptoms for PD patients’ prognosis remains unknown.MethodsIn this retrospective cohort study, patients who started PD during 1 January 2006 to 31 January 2018 were included. Patients’ predialysis symptoms and clinical parameters were obtained. Both the short- and long-term patients’ outcome were investigated by Cox regression and Kaplan–Meier’s survival analysis to identify the relationship between clinical symptoms and patients'' mortality on PD.ResultsA total of 898 incident PD patients were included. The anorexia (58%) was the most common predialysis symptom in the present cohort, followed by insomnia (32.7%), fatigue (27.6%), syndromes of heart failure (27.6%), and nausea (20.5%). The only symptom significantly associated with both six-months and 12-months mortality on PD was nausea (HR 2.359, 95% CI 1.377–4.040, p=.002 and HR 1.791, 95% CI 1.176–2.729, p=.007, respectively). But in the long-term, anorexia (HR 1.392, 95% CI 1.070–1.811, p=.014) was the only symptom significantly associated with patient''s all-cause mortality after adjusting for other confounding factors.ConclusionsOur study demonstrated that nausea and anorexia were the most important predialysis symptoms, which was associated with patients’ short- and long-term mortality on PD treatment, respectively. The results indicated that predialysis evaluation and management of symptoms of nausea and anorexia may be a possible way to improve patients’ outcome on PD.     

Radiographic Anatomy of the Native Anterior Cruciate Ligament: a Systematic Review

BackgroundIn an attempt to improve the accuracy and reproducibility of tunnel positioning, radiographs are being analyzed in an attempt to recreate the native anatomy of the ACL. Understanding the native ACL radiographic anatomy is an essential prerequisite to understand the relevance of postoperative tunnel position.Questions/PurposesWe performed a systematic review of the literature to delineate the radiographic location of the native ACL femoral and tibial footprints.MethodsA search was performed in March 2014 in PubMed, the Cochrane Collaboration Library, and EMBASE to identify all studies that evaluated the native anterior cruciate ligament (ACL) anatomy on radiographs. Various measurement methods were used in each study, and averages were obtained of the data from studies with the same measurement methods.ResultsFifteen papers were identified (which included data on 177 femora and 207 tibiae in total). Evaluation of the femoral footprint using the quadrant method on lateral knee radiographs showed that the average percent distance location of the anteromedial (AM) bundle and posterolateral (PL) bundle was 22.8% (95% confidence interval (CI) 16.59–28.90) and 32.5% (95% CI 27.71–37.26) from the posterior condyle, respectively, and 23.2% (95% CI 19.52–26.94) and 50.0% (95% CI 46.16–53.76) from Blumensaat’s line, respectively. Using the Amis and Jacob method, the tibial footprint on the lateral knee radiograph average percent distances was 35.1% (95% CI 34.46–35.72) for the center of the AM bundle and 47.3% (95% CI 41.69–52.95) for the center of the PL bundle of the ACL. The femoral and tibial ACL footprints on the anteroposterior (AP) views of the knee were not well delineated by these studies.ConclusionThe information presented in this systematic review offers surgeons another important tool for accurate ACL footprint identification.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-014-9417-5) contains supplementary material, which is available to authorized users.     

Blood Transfusions May Have Limited Effect on Muscle Oxygenation After Total Knee Arthroplasty

BackgroundTraditionally, blood transfusions in the perioperative setting are used to maintain adequate delivery of nutrients and oxygen to organs. However, the effect of blood administration on tissue oxygenation in the perioperative setting remains poorly understood.Questions/PurposesThe aim of this study was to determine changes in muscle tissue oxygenation saturation (SmO₂) in response to perioperative blood transfusions.ResultsTwenty-eight patients were included in the analysis. Mean (±SD) SmO₂ before transfusion was 63.18 ± 10.04%, SpHb was 9.27 ± 1.16 g/dl, and cardiac index was 2.62 ± 0.75 L/min/m². A significant increase during the course of blood transfusion was found for SmO₂ (+3.44 ± 5.81% [95% confidence interval (CI) 1.04 to 5.84], p = 0.007), SpHb (0.74 ± 0.92 g/dl [95% CI 0.35 to 1.12], p < 0.001), and cardiac index (0.38 ± 0.51 L/min/m2 [95% CI 0.15 to 0.60], p = 0.002), respectively. However, the correlation between SmO₂ and SpHb over the course of the transfusion was negligible (ρ = 0.25 [95% CI −0.03 to 0.48]). A similar lack of correlation was found when analyzing data of those patients who showed a positive leg raise test before the start of the transfusion (ρ = 0.37 [95% CI −0.11 to 0.84]).ConclusionWe detected a statistically significant increase in SmO₂ during the course of a single unit blood transfusion compared to baseline. However, there was no evidence of a correlation between longitudinal SmO₂ and SpHb measurements.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-015-9434-z) contains supplementary material, which is available to authorized users.     

Reliability of the modified lateral pillar classification for Legg Calvé Perthes disease performed by a large group of international paediatric orthopaedic surgeons

PurposeThe modified lateral pillar classification (mLPC) is used for prognostication in the fragmentation stage of Legg Calvé Perthes disease. Previous reliability assessments of mLPC range from fair to good agreement when evaluated by a small number of observers with pre-selected radiographs. The purpose of this study was to determine the inter-observer and intra-observer reliability of mLPC performed by a group of international paediatric orthopaedic surgeons. Surgeons self-selected the radiograph for mLPC assessment, as would be done clinically.MethodsIn total, 40 Perthes cases with serial radiographs were selected. For each case, 26 surgeons independently selected a radiograph and assigned mLPC and 21 raters re-evaluated the same 40 cases to establish intra-observer reliability. Rater performance was determined through surgeon consensus using the mode mLPC as ‘gold standard’. Inter-observer and intra-observer reliability data were analysed using weighted kappa statistics.ResultsThe weighted kappa for inter-observer correlation for mLPC was 0.64 (95% confidence interval: 0.55 to 0.74) and was 0.82 (range: 0.35 to 0.99) for intra-observer correlation. Individual surgeon’s overall performance varied from 48% to 88% agreement. Surgeon mLPC performance was not influenced by years of experience (p = 0.51). Radiograph selection did not influence gold standard assignment of mLPC. There was greater agreement on cases of mild B hips and severe C hips.ConclusionsmLPC has low good inter-observer agreement when performed by a large number of surgeons with varied experience. Surgeons frequently chose different radiographs, with no impact on mLPC agreement. Further refinement is needed to help differentiate hips on the border of group B and C.Level of evidenceIII     

How Common Is Femoral Retroversion and How Is it Affected by Different Measurement Methods in Unilateral Slipped Capital Femoral Epiphysis?

BackgroundAlthough femoral retroversion has been linked to the onset of slipped capital femoral epiphysis (SCFE), and may result from a rotation of the femoral epiphysis around the epiphyseal tubercle leading to femoral retroversion, femoral version has rarely been described in patients with SCFE. Furthermore, the prevalence of actual femoral retroversion and the effect of different measurement methods on femoral version angles has yet to be studied in SCFE.Questions/purposes(1) Do femoral version and the prevalence of femoral retroversion differ between hips with SCFE and the asymptomatic contralateral side? (2) How do the mean femoral version angles and the prevalence of femoral retroversion change depending on the measurement method used? (3) What is the interobserver reliability and intraobserver reproducibility of these measurement methods?MethodsFor this retrospective, controlled, single-center study, we reviewed our institutional database for patients who were treated for unilateral SCFE and who had undergone a pelvic CT scan. During the period in question, the general indication for obtaining a CT scan was to define the surgical strategy based on the assessment of deformity severity in patients with newly diagnosed SCFE or with previous in situ fixation. After applying prespecified inclusion and exclusion criteria, we included 79 patients. The mean age was 15 ± 4 years, 48% (38 of 79) of the patients were male, and 56% (44 of 79) were obese (defined as a BMI > 95th percentile (mean BMI 34 ± 9 kg/m²). One radiology resident (6 years of experience) measured femoral version of the entire study group using five different methods. Femoral neck version was measured as the orientation of the femoral neck. Further measurement methods included the femoral head’s center and differed regarding the level of landmarks for the proximal femoral reference axis. From proximal to distal, this included the most-proximal methods (Lee et al. and Reikerås et al.) and most-distal methods (Tomczak et al. and Murphy et al.). Most proximally (Lee et al. method), we used the most cephalic junction of the greater trochanter as the landmark and, most distally, we used the center base of the femoral neck superior to the lesser trochanter (Murphy et al.). The orientation of the distal femoral condyles served as the distal reference axis for all five measurement methods. All five methods were compared side-by-side (involved versus uninvolved hip), and comparisons among all five methods were performed using paired t-tests. The prevalence of femoral retroversion (< 0°) was compared using a chi-square test. A subset of patients was measured twice by the first observer and by a second orthopaedic resident (2 years of experience) to assess intraobserver reproducibility and interobserver reliability; for this assessment, we used intraclass correlation coefficients.ResultsThe mean femoral neck version was lower in hips with SCFE than in the contralateral side (-2° ± 13° versus 7° ± 11°; p < 0.001). This yielded a mean side-by side difference of -8° ± 11° (95% CI -11° to -6°; p < 0.001) and a higher prevalence of femoral retroversion in hips with SCFE (58% [95% CI 47% to 69%]; p < 0.001) than on the contralateral side (29% [95% CI 19% to 39%]). These differences between hips with SCFE and the contralateral side were higher and ranged from -17° ± 11° (95% CI -20° to -15°; p < 0.001) based on the method of Tomczak et al. to -22° ± 13° (95% CI -25° to -19°; p < 0.001) according to the method of Murphy et al. The mean overall femoral version angles increased for hips with SCFE using more-distal landmarks compared with more-proximal landmarks. The prevalence of femoral retroversion was higher in hips with SCFE for the proximal methods of Lee et al. and Reikerås et al. (91% [95% CI 85% to 97%] and 84% [95% CI 76% to 92%], respectively) than for the distal measurement methods of Tomczak et al. and Murphy et al. (47% [95% CI 36% to 58%] and 60% [95% CI 49% to 71%], respectively [all p < 0.001]). We detected mean differences ranging from -19° to 4° (all p < 0.005) for 8 of 10 pairwise comparisons in hips with SCFE. Among these, the greatest differences were between the most-proximal methods and the more-distal methods, with a mean difference of -19° ± 7° (95% CI -21° to -18°; p < 0.001), comparing the methods of Lee et al. and Tomczak et al. In hips with SCFE, we found excellent agreement (intraclass correlation coefficient [ICC] > 0.80) for intraobserver reproducibility (reader 1, ICC 0.93 to 0.96) and interobserver reliability (ICC 0.95 to 0.98) for all five measurement methods. Analogously, we found excellent agreement (ICC > 0.80) for intraobserver reproducibility (reader 1, range 0.91 to 0.96) and interobserver reliability (range 0.89 to 0.98) for all five measurement methods in healthy contralateral hips.ConclusionWe showed that femoral neck version is asymmetrically decreased in unilateral SCFE, and that differences increase when including the femoral head’s center. Thus, to assess the full extent of an SCFE deformity, femoral version measurements should consider the position of the displaced epiphysis. The prevalence of femoral retroversion was high in patients with SCFE and increased when using proximal anatomic landmarks. Since the range of femoral version angles was wide, femoral version cannot be predicted in a given hip and must be assessed individually. Based on these findings, we believe it is worthwhile to add evaluation of femoral version to the diagnostic workup of children with SCFE. Doing so may better inform surgeons as they contemplate when to use isolated offset correction or to perform an additional femoral osteotomy for SCFE correction based on the severity of the slip and the rotational deformity. To facilitate communication among physicians and for the design of future studies, we recommend consistently reporting the applied measurement technique.Level of EvidenceLevel III, prognostic study.     

Reliability and reproducibility analysis of the AOSpine thoracolumbar spine injury classification system by Chinese spinal surgeons

Purpose

The objective of this study was to analyze the interobserver reliability and intraobserver reproducibility of the new AOSpine thoracolumbar spine injury classification system in young Chinese orthopedic surgeons with different levels of experience in spinal trauma. Previous reports suggest that the new AOSpine thoracolumbar spine injury classification system demonstrates acceptable interobserver reliability and intraobserver reproducibility. However, there are few studies in Asia, especially in China.

Methods

The AOSpine thoracolumbar spine injury classification system was applied to 109 patients with acute, traumatic thoracolumbar spinal injuries by two groups of spinal surgeons with different levels of clinical experience. The Kappa coefficient was used to determine interobserver reliability and intraobserver reproducibility.

Results

The overall Kappa coefficient for all cases was 0.362, which represents fair reliability. The Kappa statistic was 0.385 for A-type injuries and 0.292 for B-type injuries, which represents fair reliability, and 0.552 for C-type injuries, which represents moderate reliability. The Kappa coefficient for intraobserver reproducibility was 0.442 for A-type injuries, 0.485 for B-type injuries, and 0.412 for C-type injuries. These values represent moderate reproducibility for all injury types. The raters in Group A provided significantly better interobserver reliability than Group B (P < 0.05). There were no between-group differences in intraobserver reproducibility.

Conclusions

This study suggests that the new AO spine injury classification system may be applied in day-to-day clinical practice in China following extensive training of healthcare providers. Further prospective studies in different healthcare providers and clinical settings are essential for validation of this classification system and to assess its utility.

     

Vascular repair after firearm injury is associated with increased morbidity and mortality

ObjectiveFirearm injuries have high morbidity and mortality. Presentation of injuries requiring concurrent vascular repair and its outcomes are unclear. Our study's objective was to characterize the injury details and to assess the associated mortality and morbidity after vascular repair.MethodsThe National Inpatient Sample was queried from 1993 to 2014 for all firearm injuries. International Classification of Diseases, Ninth Revision codes were used to identify firearm injuries and those who also underwent a vascular repair. Multivariable analysis was used to assess the effect of a concurrent vascular repair on outcomes.ResultsThere were 648,662 firearm injuries identified; 63,973 (9.9%) involved a vascular repair. Overall, 88.7% of patients were male, and Medicaid was the most common insurance (40.2%). Intents were assault or legal intervention (60%), unintentional (24.2%), and suicide (8.6%). Patients undergoing vascular repair were younger, more often of black race and male sex, and on Medicaid insurance, with a lower household income and assault/legal intent (P < .005). Patients who underwent vascular repair had a higher frequency of abdomen/pelvis and extremity injuries as well as an elevated New Injury Severity Score (P < .005). Patients with vascular repair were more frequently treated at urban, teaching, and large hospitals (P < .005). Overall mortality rate was 2.2%; patients who underwent vascular repair had a higher mortality compared with those without (5.51% vs 1.98%; P < .001). Patients with vascular repair had higher rates of acute renal failure (3.1% vs 0.8%), venous thromboembolic events (0.5% vs 0.3%), pulmonary-related events (0.6% vs 0.28%), cardiac-related events (0.8% vs 0.2%), sepsis (1.4% vs 0.5%), and any complication (5.7% vs 2%; all P < .0001). Vascular repair was independently associated with mortality (odds ratio [OR], 2.68; 95% confidence interval [CI], 2.43-2.95; P < .0001). Age older than 46 years (OR, 2.01; 95% CI, 1.71-2.35; P < .0001), male sex (OR, 1.15; 95% CI, 1.05-1.25; P = .003), self-pay/no insurance (OR, 1.6; 95% CI, 1.47-1.75; P < .0001), suicide intent (OR, 3.73; 95% CI, 3.36-4.13; P < .0001), unintentional intent (OR, 1.12; 95% CI, 1.03-1.22; P < .0001), head/neck location (OR, 13.9; 95% CI, 12.5-15.6; P < .0001), Northeast region, and New Injury Severity Score >4 were independently associated with in-hospital mortality. Vascular repair was also independently associated with any complication (OR, 2.12; 95% CI, 1.98-2.28; P < .0001).ConclusionsFirearm injuries with vascular repair were independently associated with higher injury severity score and mortality. A majority of vascular repairs were performed for injury to the abdomen/pelvis and extremity with assault/legal intent, whereas head and neck injury and suicide intent were the least frequent.