An independent inter- and intra-observer agreement assessment of the Eno classification of sacroiliac joint degeneration.

BACKGROUND: Recently, a scoring system to grade sacroiliac joint (SIJ) degeneration using computed tomography (CT) scans was described. No independent evaluation has determined the inter- and intra-observer agreement using this scheme. PURPOSE: To perform an independent inter- and intra-observer agreement assessment using the Eno classification and determining gas in the SIJ. MATERIAL AND METHODS: We studied 64 patients aged ≥60 years who were evaluated with abdominal and pelvic computed tomography scans. Six physicians (three orthopaedic spine surgeons and three musculoskeletal radiologists) assessed axial images to grade SIJ degeneration into grade 0 (normal), grade 1 (mild degeneration), grade 2 (significant degeneration), and grade 3 (ankylosis). We also evaluated the agreement assessing the presence of gas in the SIJ. After a four-week interval, all cases were presented in a random sequence for repeat assessment. We determined the agreement using the kappa (κ) or weighted kappa coefficient (wκ). RESULTS: The inter-observer agreement was moderate (wκ = 0.50 [0.44-0.56]), without differences among surgeons (wκ = 0.53 [0.45-0.61]) and radiologists (wκ = 0.49 [0.42-0.57]). The agreement evaluating the presence of gas was also moderate (κ = 0.45 [0.35-0.54]), but radiologists obtained better agreement (κ = 0.61 [0.48-0.72]) than surgeons (κ = 0.29 [0.18-0.39]). The intra-observer agreement using the classification was substantial (wκ = 0.79 [0.76-0.82]), without differences comparing surgeons (wκ = 0.75 [0.70-0.80]) and radiologists (wκ = 0.83 [0.79-0.87]). The intra-rater agreement evaluating gas was substantial (κ = 0.77 [0.72-0.82]), without differences between surgeons (κ = 0.71 [0.63-0.78]) and radiologists (κ = 0.84 [0.78-0.90]). CONCLUSION: Given the only moderate agreement obtained using the Eno classification, it does not seem adequate to be used in clinical practice or in research.

An inter- and intra-rater agreement assessment of a novel classification of pyogenic spinal infections.

PURPOSE: Pola et al. described a clinical-radiological classification of pyogenic spinal infections (PSI) based on magnetic resonance imaging (MRI) features including vertebral destruction, soft tissue involvement, and epidural abscess, along with the neurological status. We performed an inter- and intra-observer agreement evaluation of this classification. METHODS: Complete MRI studies of 80 patients with PSI were selected and classified using the scheme described by Pola et al. by seven evaluators. After a four-week interval, all cases were presented to the same assessors in a random sequence for repeat assessment. We used the weighted kappa statistics (wκ) to establish the inter- and intra-observer agreement. RESULTS: The inter-observer agreement was substantial considering the main categories (wκ = 0.77; 0.71-0.82), but moderate considering the subtypes (wκ = 0.51; 0.45-0.58). The intra-observer agreement was substantial considering the main types (wκ = 0.65; 0.59-0.71), and moderate considering the subtypes (wκ = 0.58; 0.54-0.63). CONCLUSION: The agreement at the main type level indicates that this classification allows adequate communication and may be used in clinical practice; at the subtypes level, the agreement is only moderate.

Update on the Diagnosis and Management of Spinal Infections.

Pyogenic spinal infections are uncommon, but their incidence has increased. Diagnosis is based on clinical, laboratory, and imaging findings. Delayed diagnosis occurs frequently and can lead to poor outcomes. Early radiographic findings are nonspecific; MRI is the best imaging study for diagnosis. The goal of treatment is to eradicate infection, prevent recurrence, preserve spinal stability, avoid deformity, relieve pain, and prevent or reverse neurologic deficit. Current guidelines recommend antibiotics be administered for 6 weeks if there is resolution of symptoms and normalization of inflammatory parameters. Surgery is required in patients with neurologic deficit, uncontrolled sepsis, spinal instability, deformity, and failure of medical treatment and to manage epidural abscess. Classic treatment of epidural abscess is surgical, but recent studies have challenged this approach. Surgical techniques used to manage these infections are varied; they include anterior, posterior, and combined approaches, and minimally invasive surgery. Current management has decreased mortality; however, the prognosis is affected by treatment failure, recurrent infection, or potential of persistent disability secondary to deformity, chronic pain, or permanent neurologic impairment.

Mid and lower thoracic kyphosis changes during adulthood: the influence of age, sex and thoracic coronal curvature.

INTRODUCTION: There is conflicting data on how thoracic kyphosis changes throughout adulthood. We evaluated mid and lower thoracic kyphosis (MTK) in various age groups and the influence of age, sex and coronal curve (CC) on MTK. MATERIAL AND METHODS: We studied 1323 patients 15-80 years-old (54.4% females) previously evaluated with chest radiographs. We established three groups: patients 15-40 (group 1); 41-60 (group 2) and 61-80 years old (group 3). MTK (T5-T12) and CC were measured using Cobb's method. We established differences in MTK between groups using ANOVA with Bonferroni correction. We performed a correlation analysis of MTK with age and CC, and a linear regression analysis to determine if age, sex and CC independently predicted MTK. RESULTS: MTK increased with older age: mean MTK group 1 = 23.4°; group 2 = 27.9° and group 3 = 34.4°, p < 0.01. The increase in MTK was observed in both genders. Scoliosis was more common in females (15.4%) than in males (6.7%), p < 0.01. MTK was correlated with age (r = 0.4; p < 0.01) and slightly correlated with CC (r = 0.07, p < 0.01). MTK was larger in females than in males (29.1° vs. 27.6°, p < 0.01). Age (ß-coefficient = 0.26) and CC (ß-coefficient = 0.14), but not sex, independently influenced MTK in the regression analysis. CONCLUSION: MTK increases with advancing age during adulthood in both genders; CC, but not sex, was an independent predictor of MTK.

A novel intraoperative technique seeding morselized bone tissue into pediatric blood culture bottles improves microbiological diagnosis in patients with foot and ankle osteomyelitis.

BACKGROUND: Osteomyelitis, particularly cases involving the foot and ankle, is a challenging situation that frequently leads to amputations and major sequelae. Targeted antibiotics treating an identified pathogen are key to a successful outcome; however, traditional culture methods for bone tissue have poor sensitivity. This study prospectively compared a novel method for obtaining and processing infected bone tissue with the standard technique. METHODS: 107 patients presenting with a diagnosis of osteomyelitis of the foot and ankle between 2008 and 2017 were prospectively included. Diagnosis was done according to clinical, laboratory and imaging findings. We obtained paired samples of bone tissue from all patients; they were processed through a usual culture method (UCM), but they were also morselized and seeded into pediatric blood culture bottles (PBCBs). We compared the culture yield and the number of agents detected using both the McNemar and the Mann-Whitney tests, respectively. RESULTS: We studied 107 patients (63 with diabetic foot infection and 44 with nondiabetic osteomyelitis). The causative agent was identified in 60.7% of cases using the UCM and in 97.2% of cases using PBCBs (p < 0.001). We detected a mean of 1.05 ± 1.03 bacteria using the UCM and 1.67 ± 0.92 bacteria using PBCBs (p < 0.01). CONCLUSION: Cultures using morselized bone seeded in PBCBs identified the causative agent in a significantly larger percentage than the UCM. Additionally, this method identified a larger number of pathogen agents. A better agent identification method has advantages such as identifying more specific antibiotic treatment in these cases.

Scheuermann's disease in patients 15-40 years old: A study to determine its prevalence and its relationship with age and sex using chest radiographs as screening tool.

BACKGROUND: There is insufficient knowledge of the epidemiology of Scheuermann's disease. The data available comes from estimations from young adults with obvious deformity, from studies evaluating children who may not have developed the deformity yet, or from older populations who can develop vertebral wedging secondary to other causes. We aimed to determine the prevalence of Scheuermann's disease in patients 15-40 years old using plain chest radiographs as a screening tool. METHODS: We evaluated 454 patients aged 15-40 years old studied using standing plain chest radiographs. We measured thoracic kyphosis from T5 to T12; using the intraclass correlation coefficient (ICC), we determined inter- and intra-observer agreement. To determine the prevalence of Scheuermann's disease we used the Sorensen criteria. We performed a correlation analysis of thoracic kyphosis and age, and a linear regression to determine the impact of age and sex on the kyphosis angle. RESULTS: The prevalence of Scheuermann's disease was 2.2% (0.9-3.5%). The prevalence was not different in females (1.4%) and males (2.8%), p = 0.36. Inter-and intra-observer agreements were excellent: ICC = 0.93 (0.84-0.97) and 0.97 (0.95-0.98). There was a small positive correlation of kyphosis angle with age (r = 0.110; p = 0.019). Linear regression revealed that age (ß = 0.138; p = 0.019) was an independent predictor of kyphosis angle, but sex was not (ß-coefficient = 0.007; p = 0.994). CONCLUSION: We found a prevalence of Scheuermann's disease of 2.2%, without significant differences between males and females. Age independently influenced the kyphosis angle; sex did not. This study allows a better understanding of the epidemiology of Scheuermann's disease.

Incidental identification of vertebral compression fractures in patients over 60 years old using computed tomography scans showing the entire thoraco-lumbar spine.

INTRODUCTION: Vertebral compression fractures (VCF) are frequently asymptomatic; incidental diagnosis is a valuable opportunity to identify low bone mass and to start treatment. We aimed to determine the proportion of patients over 60 years old evaluated with chest plus abdominal and pelvic computed tomography (CT) scans, allowing visualization of the entire thoraco-lumbar spine, who incidentally present VCF. MATERIALS AND METHODS: We evaluated 300 patients over 60 years old who under went chest plus abdominal and pelvic CT scans. Using sagittal reformats we looked for VCF using the method described by Genant. Accordingly, VCF were classified into mild, moderate or severe. We also determined the percentage of VCF described in the radiological reports. RESULTS: In our cohort [median age 72.5 years (61-94)], 45.67% were males and 54.33% were females. In total, 43 patients (14.33%) had at least one VCF; 32 (10.67%) had one VCF, whereas 11 (3.67%) exhibited multiple VCF, with a total of 84 fractures. 42 were mild fractures, 29 moderate and 13 severe. The proportion of males (13.87%) and females (14.72%) with VCF was not different (p = 0.83). Patients with VCF were older than those without VCF (p < 0.01). Only age but not sex was independently associated with the presence of VCF. Only 32.56% of patients we identified as having a VCF had a description in their report (14 patients). CONCLUSION: An important proportion of patients over 60 years old evaluated with chest plus abdominal and pelvic CT scans present VCF. The reporting of these VCF is insufficient; radiologists and clinicians should include their detection in their search pattern.

Prevalence of lumbar high-intensity zone: assessment using a screening tool independent of spinal symptoms.

High-intensity zone is an area of high-intensity signal within the posterior annulus fibrosus observed in magnetic resonance imaging; initially described in painful discs, recent studies have described similar prevalence in symptomatic and asymptomatic subjects. Since its' prevalence in the general population has not been established, we used a screening tool independent of spinal symptoms to determine high-intensity zone prevalence. We studied 217 patients evaluated with abdominal-pelvic magnetic resonance imaging; we looked for high-intensity zone, disc degeneration, spondylolysis, spondylolisthesis, Modic changes and scoliosis. We determined if these variables, age and sex affected the presence of high-intensity zone; through a logistic regression analysis we evaluated their independent effect. Patients' mean age was 56.3±17.4 years; 66.8% were females. Prevalence of high-intensity zone (11.06%) was larger in males (18.06%) than females (7.59%), p = 0.02. Patients with and without high-intensity zone did not differ in age or presence of scoliosis. High-intensity zone was more frequent in degenerated discs, but not in levels with spondylolisis, spondylolisthesis or Modic changes. Male sex (OR = 2.3, 1.04-5.38) and disc degeneration (OR = 6.76, 1.77-25.81) independently influenced the presence of high-intensity zone. The prevalence of high-intensity zone in this sample of the general population, including 217 subjects, was 11.06%. Similarly, a recent meta-analysis mentioned a 9.5% prevalence in asymptomatic subjects; on the other hand it stressed a 10.4% prevalence in symptomatic subjects. All these data do not plead for a strict correlation between high-intensity zone and low back pain complaints.

Does the META score evaluating osteoporotic and metastatic vertebral fractures have enough agreement to be used by orthopaedic surgeons with different levels of training?

PURPOSE: Differentiating osteoporotic vertebral fractures (OVF) from metastatic vertebral fractures (MVF) is difficult. A magnetic resonance imaging (MRI)-based score (META score) aiming to differentiate OVF and MVF was recently published; however, an independent agreement assessment is required before the score is used. We performed such independent agreement evaluation, including raters with different levels of training. METHODS: Sixty-four patients with confirmed OVF or MVF were evaluated by six raters (three spine surgeons and three orthopaedic residents) using the META score. We used the intra-class correlation coefficient (ICC) to evaluate inter- and intra-observer agreement and the kappa statistic (κ) to determine the agreement for individual score criteria. We calculated the area under the receiver-operating characteristic curve (AUC) to establish the score accuracy. RESULTS: The inter-observer agreement was poor [ICC = 0.22 (0.12-0.33)]; spine surgeons [ICC = 0.75 (0.66-0.83)] had better agreement than that of residents [ICC = 0.06 (- 0.07 to 0.23)]. The intra-observer agreement was poor [ICC = 0.15 (- 0.04 to 0.30)]; both spine surgeons [ICC = 0.21 (0.05-0.41)] and residents exhibited poor agreement [ICC = - 0.06 (- 0.40 to 0.20)]. The agreement for each specific criterion varied from κ = 0.24 to κ = 0.38. The AUC was 0.57 (0.64 for spine surgeons and 0.51 for residents, p < 0.01). CONCLUSION: The inter-observer agreement using the META score was adequate for spine surgeons but not for residents; the intra-observer agreement was poor. These results do not support the standard use of the META score to differentiate OVF and MVF. These slides can be retrieved under Electronic Supplementary Material.

Is a single-level measurement of paraspinal muscle fat infiltration and cross-sectional area representative of the entire lumbar spine?

PURPOSE: Lumbar paraspinal muscle morphology has recently been evaluated in several studies with conflicting results. Several studies have performed single-slice evaluations of paraspinal muscle morphology, whereas other studies have done a multi-level assessment; this methodological difference might explain the observed different results. Our study evaluated if a single-slice axial measurement is representative of the entire lumbar musculature. METHODS: We included 80 adult patients who were consecutively evaluated with magnetic resonance imaging (MRI) for spinal symptoms. Using T2-weighted axial images, we measured the fat signal fractions (FSF) and cross-sectional area (CSA) of the erector spinae and multifidus at the five levels of the lumbar spine (from L1-L2 to L5-S1). We used the ANOVA test for repeated measurements (with Bonferroni correction) to compare the FSF and CSA among the levels. RESULTS: Erector spinae showed an increasing FSF from L1-L2 to L5-S1; all erector spinae FSF comparisons among the different levels were significantly different. Multifidus FSF also increased caudally below L2-L3, although significant differences were observed only with two or more levels of distance. The CSA of the erector spinae showed a caudal decrease (L4-L5 and L5-S1 being significantly smaller than all the levels above). The CSA of the multifidus showed that all levels exhibited a significantly different area compared to their adjacent level (except L5-S1 compared to L4-L5). CONCLUSIONS: No single-level FSF or CSA is representative of the whole lumbar spine. A standardized multi-level evaluation of the paraspinal musculature should be used in future research.

Lumbar paraspinal muscle fat infiltration is independently associated with sex, age, and inter-vertebral disc degeneration in symptomatic patients.

PURPOSE: To determine the association of paraspinal muscles and psoas relative cross-sectional area (RCSA) and fat signal fraction (FSF) with sex, age, and intervertebral disc degeneration (IDD) in symptomatic patients. METHODS: We retrospectively evaluated 80 adult patients with spinal symptoms using T2-weighted magnetic resonance images. We determined RCSA and FSF of the paraspinal muscles (erector spinae and multifidus) and psoas from L1-L2 to L5-S1; we determined IDD using the Pfirrmann classification. We compared differences in muscle RCSA and FSF based on sex and IDD, and we correlated age and IDD with RCSA and FSF. Using multivariate linear regression analyses, we determined the impact of sex, age, and IDD on RCSA and FSF. RESULTS: Men exhibited larger psoas RCSA but not larger paraspinal muscles RCSA than women. Women had larger FSF in the paraspinal muscles and psoas. Increasing IDD was associated with larger FSF if ≥2 Pfirrmann grades were observed. IDD correlated with FSF of the paraspinal muscles, and age correlated with FSF of the paraspinal muscles and psoas. IDD was less consistently correlated with RCSA, but age correlated negatively with RCSA of all three muscles. Linear regression analyses demonstrated that sex, age, and IDD were each independently associated with FSF of the paraspinal muscles; additionally, sex and age, but not IDD, were associated with psoas FSF. RCSA was less consistently influenced by these three variables. CONCLUSIONS: Sex, age, and IDD are independently associated with paraspinal muscles FSF; only sex and age influence psoas FSF.

Calcium hydroxyapatite crystal deposition with intraosseous penetration involving the posterior aspect of the cervical spine: a previously unreported cause of neck pain.

PURPOSE: Calcific tendinitis is a frequent disorder caused by hydroxyapatite crystal deposition; however, bone erosions from calcific tendinitis are unusual. The spinal manifestation of this disease is calcific tendinitis of the longus colli muscle; this disease has never been described in the posterior aspect of the spine. We report a case of calcium hydroxyapatite crystal deposition involving the posterior cervical spine eroding the bone cortex. METHODS: A 57-year-old woman presented with a 5-month history of left-sided neck pain. Radiographs showed C4-C5 interspinous calcification with lytic compromise of the posterior arch of C4. Magnetic resonance imaging confirmed a lytic lesion of the posterior arch of C4, with a soft tissue mass extending to the C4-C5 interspinous space; calcifications were observed as very low signal intensity areas on T1 and T2 sequences, surrounded by gadolinium-enhanced soft tissues. A computed tomography (CT) scan confirmed the bone erosions and the soft tissue calcifications. RESULTS: A CT-guided needle biopsy was performed; it showed vascularized connective tissue with inflammatory histiocytic infiltration and multinucleated giant cells; Alizarin Red stain confirmed the presence of hydroxyapatite crystals. The patient was treated with anti-inflammatories for 2 weeks. She has been asymptomatic in a 6-month follow-up; a CT scan at the last follow-up revealed reparative remodeling of bone erosions. CONCLUSION: This is the first report of calcium hydroxyapatite crystal deposition with intraosseous penetration involving the posterior aspect of the cervical spine. Considering that this unusual lesion can be misinterpreted as a tumor or infection, high suspicion is required to avoid unnecessary surgical procedures.

Do Orthopaedic Oncologists Agree on the Diagnosis and Treatment of Cartilage Tumors of the Appendicular Skeleton?

BACKGROUND: Distinguishing a benign enchondroma from a low-grade chondrosarcoma is a common diagnostic challenge for orthopaedic oncologists. Low interrater agreement has been observed for the diagnosis of cartilaginous neoplasms among radiologists and pathologists, but, to our knowledge, no study has evaluated inter- and intraobserver agreement among orthopaedic oncologists grading these lesions using initial clinical and imaging information. Determining such agreement is important since it reflects the certainty in the diagnosis by orthopaedic oncologists. Agreement also is important as it will guide future treatment and prognosis, considering that there is no gold standard for diagnosis of these lesions. QUESTIONS/PURPOSES: (1) to determine inter- and intraobserver agreement among a multinational panel of expert orthopaedic oncologists in diagnosing cartilaginous neoplasms based on their assessment of clinical symptoms and imaging at diagnosis. (2) To describe the most important clinical and imaging features that experts use during the initial diagnostic process. (3) To determine interobserver agreement for proposed initial treatment strategies for cartilaginous neoplasms by this panel of evaluators. METHODS: Thirty-nine patients with intramedullary cartilaginous neoplasms of the appendicular skeleton of various histopathologic grades were selected and classified as having benign, low-grade malignant, or intermediate- or high-grade malignant neoplasms by 10 experienced orthopaedic oncologists based on clinical and imaging information. Additionally, they chose the three most important clinical or imaging features for the diagnosis of these neoplasms, and they proposed a treatment strategy for each patient. The Kappa coefficient (κ) was used to determine inter- and intraobserver agreement. RESULTS: Inter- and intraobserver agreements were only fair to good, κ = 0.44(95% CI, 0.41-0.48) and κ = 0.62 (95% CI, 0.52-0.72), respectively. The three factors most frequently identified as helpful in making the diagnosis by our panel were cortical involvement in 65% of evaluations (253/390), neoplasm size in 51% (198/390), and pain in 50% (194/390). The interobserver agreement for the proposed initial treatment strategy after diagnosis was poor (κ = 0.21; 95% CI, 0.18-0.24). CONCLUSIONS: This study showed barely fair interobserver and fair to good intraobserver agreement for grading of intramedullary cartilaginous neoplasms by orthopaedic oncologists using initial clinical and imaging findings. These results reflect the insufficient guidance interpreting clinical and imaging features, and the limitations of the systems we use today when making these diagnoses. In the same way, they generate concern for the implications that this may have on different treatment strategies and the future prognosis of our patients. Future studies should build on these observations and focus on clarifying our criteria of diagnosis so that treatment recommendations are standardized regardless of the treating institution or oncologist. LEVEL OF EVIDENCE: Level III, diagnostic study.

Spondylolysis and spina bifida occulta in pediatric patients: prevalence study using computed tomography as a screening method.

PURPOSE: The prevalence of spondylolysis reported from radiograph-based studies has been questioned in recent computed tomography (CT)-based studies in adults; however, no new data are available in pediatric patients. Spina bifida occulta (SBO), which has been associated to spondylolysis, may be increasing its prevalence, according to recent studies in adults in the last decades, but without new data in pediatric patients. We aimed to determine the prevalence of spondylolysis and SBO in pediatric patients using abdomen and pelvis CT as a screening tool. METHODS: We studied 228 patients 4-15 years old (107 males), who were evaluated with abdomen and pelvis CT scans for reasons not related to the spine. The entire lumbo-sacral spine was evaluated to detect the presence of spondylolysis and SBO. We compared the prevalence of spondylolysis in patients with and without SBO. A logistic regression analysis was performed to determine the effect of age and sex as independent predictors of spondylolysis and SBO. RESULTS: The prevalence of spondylolysis was 3.5 % (1.1-5.9 %); 2/8 patients presented with olisthesis, both with grade I slip. The prevalence of SBO was 41.2 % (34.8-59.2 %) (94 patients). Spondylolysis was not more frequent in patients with SBO than in patients without SBO. Male sex and decreasing age independently predicted the presence of SBO, but not of spondylolysis. CONCLUSION: We observed a 3.5 % prevalence of spondylolysis and a 41.2 % prevalence of SBO. SBO was significantly more frequent in males and younger patients.

The prevalence of degenerative or incidental findings in the lumbar spine of pediatric patients: a study using magnetic resonance imaging as a screening tool.

PURPOSE: Several studies using magnetic resonance imaging (MRI) to evaluate the lumbar spine in adults have shown a large prevalence of degenerative changes in asymptomatic subjects; however, studies in pediatric patients are scarce. Those studies have suggested a lower rate of degenerative findings in adolescents than in adults, but the actual prevalence of MRI findings in the pediatric population has not yet been determined. We aimed to determine the prevalence of degenerative changes in the lumbar spine of pediatric patients using abdominal and pelvic MRI as the screening tool. METHODS: We studied 103 patients (mean age 6.6 years) who were evaluated with abdominal and pelvic MRI for indications that were not spine related. The entire lumbo-sacral spine was evaluated to detect the presence of disc degeneration (DD), disc displacement, anular rupture with high-intensity zone (HIZ) and Modic changes. RESULTS: In our population, 10.7 % [4.9-16.5] had at least one disc classified as Pfirrmann 2, and no patients presented discs classified as Pfirrmann 3, 4 or 5; patients exhibiting discs classified as Pfirrmann 2 were significantly older than patients who had only Pfirrmann 1 discs. The prevalence of disc bulging was 1 % [0-2.9]. No patients presented disc herniation (including protrusion or extrusions); additionally, no patients exhibited HIZ or Modic changes. CONCLUSIONS: Incidental findings related to DD are very uncommon at this early age, in contrast to findings described in adults or later in adolescence.

The Pfirrmann classification of lumbar intervertebral disc degeneration: an independent inter- and intra-observer agreement assessment.

PURPOSE: Grading inter-vertebral disc degeneration (IDD) is important in the evaluation of many degenerative conditions, including patients with low back pain. Magnetic resonance imaging (MRI) is considered the best imaging instrument to evaluate IDD. The Pfirrmann classification is commonly used to grade IDD; the authors describing this classification showed an adequate agreement using it; however, there has been a paucity of independent agreement studies using this grading system. The aim of this study was to perform an independent inter- and intra-observer agreement study using the Pfirrmann classification. METHODS: T2-weighted sagittal images of 79 patients consecutively studied with lumbar spine MRI were classified using the Pfirrmann grading system by six evaluators (three spine surgeons and three radiologists). After a 6-week interval, the 79 cases were presented to the same evaluators in a random sequence for repeat evaluation. The intra-class correlation coefficient (ICC) and the weighted kappa (wκ) were used to determine the inter- and intra-observer agreement. RESULTS: The inter-observer agreement was excellent, with an ICC = 0.94 (0.93-0.95) and wκ = 0.83 (0.74-0.91). There were no differences between spine surgeons and radiologists. Likewise, there were no differences in agreement evaluating the different lumbar discs. Most differences among observers were only of one grade. Intra-observer agreement was also excellent with ICC = 0.86 (0.83-0.89) and wκ = 0.89 (0.85-0.93). CONCLUSIONS: In this independent study, the Pfirrmann classification demonstrated an adequate agreement among different observers and by the same observer on separate occasions. Furthermore, it allows communication between radiologists and spine surgeons.

A comparative agreement evaluation of two subaxial cervical spine injury classification systems: the AOSpine and the Allen and Ferguson schemes.

PURPOSE: We performed an agreement study using two subaxial cervical spine classification systems: the AOSpine and the Allen and Ferguson (A&F) classifications. We sought to determine which scheme allows better agreement by different evaluators and by the same evaluator on different occasions. METHODS: Complete imaging studies of 65 patients with subaxial cervical spine injuries were classified by six evaluators (three spine sub-specialists and three senior orthopaedic surgery residents) using the AOSpine subaxial cervical spine classification system and the A&F scheme. The cases were displayed in a random sequence after a 6-week interval for repeat evaluation. The Kappa coefficient (κ) was used to determine inter- and intra-observer agreement. RESULTS: Inter-observer: considering the main AO injury types, the agreement was substantial for the AOSpine classification [κ = 0.61 (0.57-0.64)]; using AO sub-types, the agreement was moderate [κ = 0.57 (0.54-0.60)]. For the A&F classification, the agreement [κ = 0.46 (0.42-0.49)] was significantly lower than using the AOSpine scheme. Intra-observer: the agreement was substantial considering injury types [κ = 0.68 (0.62-0.74)] and considering sub-types [κ = 0.62 (0.57-0.66)]. Using the A&F classification, the agreement was also substantial [κ = 0.66 (0.61-0.71)]. No significant differences were observed between spine surgeons and orthopaedic residents in the overall inter- and intra-observer agreement, or in the inter- and intra-observer agreement of specific type of injuries. CONCLUSION: The AOSpine classification (using the four main injury types or at the sub-types level) allows a significantly better agreement than the A&F classification. The A&F scheme does not allow reliable communication between medical professionals.

An assessment of the Chilean National Examination of Orthopaedic Surgery.

BACKGROUND: The Chilean National Examination of Orthopaedic Surgery (EMNOT) has been administered since 2009. It was developed to determine whether individual residents are meeting minimal knowledge standards at the end of their training programs. METHODS: We performed a retrospective evaluation of the EMNOT for all years it has been administered (2009-2015). The test was analyzed for content, taxonomy of questions asked (1: direct recall; 2: diagnosis; 3: evaluation/decision-making), residents' performance, difficulty index and discrimination index. RESULTS: During the years of EMNOT administration, the most frequently tested areas have been pediatric orthopaedics (22.9 %), spine (13.8 %), general orthopaedics (13.8 %) and musculoskeletal trauma (9.9 %). A significant increase in questions with images was observed, as well as a significant decrease in the percentage of Type 1 and an increase in Type 3 questions. The Difficulty Index showed a medium level of difficulty for all years the examination has been administered. The Discrimination Index showed good discrimination in 2009, fair discrimination from 2010 through 2012, and excellent discrimination from 2013 through 2015. CONCLUSION: The EMNOT has evolved over several years to include better quality questions, better discrimination, and a more representative distribution of questions covering the different orthopaedic sub-specialties. This examination represents an effective instrument for quality assurance of orthopaedic residency programs in Chile.

Does Pathogen Identification Influence the Clinical Outcomes in Patients With Pyogenic Spinal Infections?

STUDY DESIGN: Retrospective study. OBJECTIVE: To study the clinical outcomes of patients suffering from pyogenic spinal infections (PSI), by comparing the outcomes of patients with an identified microbiological agent with those of patients without an identified pathogen. SUMMARY OF BACKGROUND DATA: PSI is associated with significant risks for morbidity and mortality. Specific antibiotic treatment has been considered a key to successful medical treatment; however, clinicians frequently treat patients with PSI without an identified agent. A paucity of data is available comparing the clinical outcomes of patients with or without an identified pathogen. MATERIALS AND METHODS: The records of 97 consecutive patients discharged from a University Hospital with the diagnosis of PSI during a 14-year period were retrospectively reviewed. Patients' demographics, etiological agent, comorbidities, site of infection, white blood cell count, erythrocyte sedimentation rate, C-reactive protein at the time of presentation, neurological impairment, length of hospital stay, and mortality were registered to compare the clinical outcomes of patients with an identified pathogen with those of patients without an identified agent. RESULTS: The causative organism was identified in 74 patients (76.3%). Patients with microbiological diagnosis were younger, and a larger percentage of them exhibited elevated C-reactive protein value; however, they were not different from those without an identified agent in terms of sex, site of infection, comorbidities, and the presence of a concomitant infection. Our study could not demonstrate different neurological outcomes, length of stay, or mortality rates among the 2 groups. CONCLUSIONS: In a large series of patients with PSI, we did not demonstrate differences in clinical outcomes using empirical antibiotics in patients without an identified pathogen compared with patients with an identified microbiological agent receiving specific antibiotics. Future prospective multicenter studies should be conducted to obtain an answer to this important clinical question.