Correlation Analysis Between Computed Tomography and Magnetic Resonance Imaging for Assessing Thoracic Pedicle Morphology.

OBJECTIVE: This study aimed to determine the accuracy and reliability of using magnetic resonance imaging (MRI) to characterize thoracic pedicle morphology in the normal population. METHODS: Computed tomography (CT) and MRI datasets of 63 surgically treated patients were included in the study. Bilateral T3, T6, T9, and T12 vertebral levels were evaluated for the type of pedicle, pedicle chord length, and pedicle isthmic diameter on both MRI and CT scans. Pedicles were classified according to Sarwahi et al. into type A (normal pedicle), >4 mm cancellous channel; type B, 2-4 mm channel; type C, completely cortical channels >2 mm; and type D, <2 mm cortical bone channel. RESULTS: Of 504 pedicles, 294 were classified as type A, 173 as type B, 24 as type C, and 13 as type D based on a CT scan. MRI had an overall accuracy rate of 92.86% for detecting type A, 96.53% for type B, and 100% for type C and type D compared with CT scans. Regarding the thoracic levels, MRI had an overall concordance of 97.98% at T3 level, 94.43% at T6 level, 98.11% at T9 level, and 99.3% at T12 level with CT readings. Comparing measurements between MRI and CT studies for pedicle isthmic diameter and pedicle chord length showed moderate to good reliability at all measured levels. CONCLUSIONS: Pedicle measurements obtained by MRI may be used to estimate pedicle dimensions, allowing surgeons to preoperatively determine pedicle screw sizes based on MRI scans alone.

Diagnostic Reliability of Computed Tomography in Predicting Posterior Ligamentous Complex Injury in Traumatic Lower Lumbar Fracture.

OBJECTIVE: Though magnetic resonance imaging (MRI) is the primary modality of investigation for determining the extent of PLC injuries in lower lumbar fractures (L3-L5), the reliability of computed tomography (CT) has not been well defined. The main objective of this study is to analyze the diagnostic accuracy of combined CT findings for detecting posterior ligamentous complex injury in patients with lower lumbar fractures. METHODS: We retrospectively analyzed data from 108 patients who presented with traumatic lower lumbar fractures. CT parameters like loss of vertebral body height, local kyphosis, retropulsion of fracture fragment, interlaminar distance (ILD), interspinous distance (ISD), supraspinous distance (SSD), interpedicular distance (IPD), canal compromise, facet joint diastasis in axial images (FJDA) and sagittal images (FJDS), presence of lamina and spinous process fracture were calculated using axial and sagittal CT images. The presence or absence of PLC injury was determined using MRI as a reference standard. RESULTS: Among 108 patients PLC injury was identified in 57 (52.8%). On univariate analysis local kyphosis, retropulsion of fracture fragment, ILD, IPD, FJDS, FJDA, and the presence of spinous process fracture were found to be significant (P < 0.05) in predicting PLC injury. Whereas on multivariate logistic regression analysis, FJDS (P= 0.039), and FJDA (P= 0.003) were found to be variables independently associated with PLC injury. CONCLUSION: Among the various CT parameters, facet joint diastasis (FJDS > 4.2 mm and FJDA > 3.5 mm) is the most reliable factor in determining PLC injury.

Multivertebral Kaposiform hemangioendothelioma presenting as scoliosis - A case report and review of literature.

Kaposiform hemangioendothelioma (KHE) is a rare, locally invasive vascular tumour of childhood that may occur in soft tissue or bones, and is associated with cutaneous plaques and Kasabach-Merritt phenomenon (KMP). We present an instance of a 9-year-old girl with primary vertebral involvement of KHE, whose clinical presentation was with painless, progressive scoliosis alone, sans cutaneous markers. We highlight the imaging features of this rare manifestation and importance of histopathological diagnosis for optimal management.

Role of impaction bone grafting of allografts in the management of benign lesions of the proximal femur.

Purpose of study: The use of allografts to reconstruct benign lesions of the proximal femur after curettage has seldom been reported. We report our experience of impaction bone grafting of only allografts combined with osteosynthesis to manage benign lesions involving the proximal femur. Materials and methods: Between 2013 and 2019, 35 patients of a mean age of 23.8 years (14-41) who had a biopsy proven benign pathology and a median pre-operative Mirels' score of 9 (8-11) were managed using extended curettage, impaction bone grafting of allografts combined with osteosynthesis through a lateral approach. Radiographs were assessed to see for any recurrence at follow-ups, and functional outcomes were assessed using Musculoskeletal Tumour Society (MSTS) score and Harris hip score (HHS). Results: At a mean follow-up was 41.5 months (23-80), patients demonstrated favorable functional outcomes with a mean MSTS of 28.3 (18-30) and a mean HHS of 94.3 (66-100) at the last follow-up. Two cases (GCT = 1; fibrous dysplasia = 1) had a recurrence of disease. Allografts demonstrated a particular integration pattern on radiographs that involved an intermediate period of lucency followed by consolidation and integration with the parent bone. Conclusion: Impaction grafting of allografts in benign lesions of the proximal femur allows adequate bony consolidation of the cavity after extended curettage and can be effectively used as a permanent solution to manage such lesions in most cases. The intermediate period of lucency seen on radiographs must not be confused for recurrence, and patients must be followed up continuously. Study design: Retrospective Case Series. Level of evidence: Level IV.

Peek screw displacement after PCL reconstruction: A radiographic red herring solved by MRI.

Posterior cruciate ligament (PCL) repair has been increasingly performed as opposed to conservative management of PCL tears, in order to protect against future osteoarthrosis and meniscal degeneration. Fixation of the graft to bone can be done with interference screws, of which those composed of a bioresorbable material such as polyetheretherketone (PEEK) are preferred, owing to their inertness, good fixation strength and superior MR imaging compatibility. However, PEEK screws (unlike titanium screws) are radiolucent, and can make accurate post-operative evaluation by radiographs challenging. This is the first reported case of loosening of PEEK screw post-PCL repair, which highlights the importance of MRI and potential pitfall of radiography in evaluating post-surgical ligament laxity.

Advanced disc degeneration, bi-planar instability and pathways of peri-discal gas suffusion contribute to pathogenesis of intradiscal vacuum phenomenon.

PURPOSE: Intradiscal vacuum phenomenon (IDVP), despite being ubiquitous, is poorly understood. The dynamic passage of peri-discal gases into the degenerated disc is a commonly accepted theory. But the reasons behind its selective appearance in some discs are unevaluated. METHODS: 721 patients with chronic low back pain ± radiculopathy, were evaluated with AP and flexion-extension lateral radiographs and MRI. IDVP was classified based on its morphology and location. Radiographic parameters including sagittal translation, sagittal angulation, lateral listhesis, eccentric disc collapse, Pfirrmann's grade, disc height, Modic changes, anterior longitudinal ligament status, and primary spinal disease at the level of IDVP was analyzed. RESULTS: IDVP was present in 342 patients, and they had a higher mean age (57.2 ± 12.5 years) than controls (p < 0.001). Eccentric disc space narrowing (26.5% vs 1.3%, p < 0.01), coronal listhesis (7.83% vs 1.1%, p < 0.001), sagittal angular motion difference (11.3 ± 4.6°, p < 0.001), higher mean disc degeneration (4.36 ± 0.69, p < 0.001), ALL disruption (30.3% vs 2.2%, p < 0.001) and Modic changes (88.6% vs 17.5%, p < 0.001) were significantly higher in IDVP discs (vs. non-IDVP). Binary logistic regression analysis indicated sagittal angular motion difference was the most predictive factor. IDVP was classified into three types-dense type (47.5%), linear (29.5%), dot type (23%). Dense type matched radiological correlations of IDVP while dot types behaved like non-IDVP discs. CONCLUSION: Modic disc-endplate contacts, ALL disruption and coronal translation could be pathways for the passage of peri-discal gases into the degenerated disc. In the pathogenesis of IDVP, advanced disc degeneration, the presence of pathways of gas transfer and angular/coronal instability seem to play complementary roles.

Modic changes are associated with activation of intense inflammatory and host defense response pathways - molecular insights from proteomic analysis of human intervertebral discs.

BACKGROUND CONTEXT: Patients with modic changes (MC) form a distinct clinical subset with reports of higher intensity of pain, poor clinical and surgical outcomes and higher incidence of recurrence. MC also is an independent risk factor for increased post-operative surgical site infection. PURPOSE: This study aimed to investigate the biological changes at molecular level, in discs with MCs. We also aim to identify biological biomarkers and potential targets for molecular therapy. STUDY DESIGN: Experimental analysis MATERIALS AND METHODS: Nucleus pulposus (NP) from 24 patients undergoing microdiscectomy for disc herniation [14 discs with MC and 10 without modic changes (NMC)] were procured. The overall expression of proteins, biological processes, protein-protein and metabolite interactions were analysed and compared. Host defense response proteins (HDRPs) and immunological pathways activated in patients with MC were documented and analysed. RESULTS: Label-free proteomic approach with stringent filters revealed a total of 208 proteins in MC and 193 in NMC groups. 45 proteins were specific to MC; 30 to NMC and 163 common to both. Downregulated proteins in MC belonged to components of extracellular matrix such as collagens (COL- 6A1, 6A2, 6A3, 11A1, 12A1, and 20A1), and proteoglycans (versican (VCAN), and biglycan (BGN)). Inflammatory molecules [plasminogen (PLG), angiogenin (ANG), fibroblast growth factor-binding protein 2 (FGFBP2), tetranectin (CLEC3B), cartilage acidic protein 1(CRTAC1), kininogen (KNG-1), chitinase-3-like protein 2 (CHI3L2), and ferritin (FTL) were expressed only in the MC group. The significantly altered pathways in MC included Fc Fragment of IgG Receptor IIIa (FCGR3A)-mediated phagocytosis, regulation of Toll-like receptors (TLR) by endogenous ligand, neutrophil and platelet degranulation. 50 HDRPs were identified in the study, 14 of which were specific to MC and included acute phase reactants, antimicrobial peptides, complement cascade proteins, inflammatory molecule and stress response proteins. Metabolite-protein interaction analysis revealed a significant interaction between 19 proteins, specifically involving ubiquitin mediating proteasome degradative pathway and an association with the metabolite-glutamic acid in the MC group. Accumulation of glutamic acid in MC discs was confirmed by quantitative amino acid analysis using High-performance liquid chromatography. CONCLUSION: Our study confirms that MC represents an intense inflammatory status and activation of host defense response and immunological pathways. Downstream effects leading to ubiquitin mediated proteasomal degradation of ECM proteins and the resulting metabolites such as glutamic acid could cause excessive pain and needs further investigation. CLINICAL SIGNIFICANCE: We have documented the expression of inflammatory molecules, immune mechanisms and host defense response proteins which throw molecular insights into the pathological mechanisms of MC. Further, ubiquitin mediated proteasomal degradation and accumulation of glutamate in discs with MC might serve as targets for molecular therapy.

Updates in postoperative imaging modalities following musculoskeletal surgery.

Postoperative imaging following orthopaedic surgeries is essential in assessing complications post-surgery and also helps plan further treatment. Combining a high degree of clinical insight with appropriate imaging can guide the treating clinician to the correct diagnosis. Imaging is quite challenging because of surgery-related soft tissue changes, especially in the early postoperative period and the presence of metal implants resulting in image scatter and metal artifacts. Newer modalities and advances in imaging have helped overcome shortcomings and assess better, especially in procedures that involve implants. Collaborative decision-making involving radiologists and clinicians has shown to be beneficial and is the way forward. This narrative review discusses the utility of imaging in evaluating postoperative complications following musculoskeletal surgeries with specific relation to trauma, arthroplasty, and tumour by discussing commonly encountered clinical scenarios.

Imaging in polytrauma - Principles and current concepts.

Imaging forms a crucial component in reducing mortality of polytraumatized patients by aiding appropriate diagnosis and guiding the emergency and definitive treatment. With the exponential expansion in the radiological armamentarium and introduction of protocols like Extended focused assessment with sonography for trauma (EFAST) and Whole body Computed tomography (WBCT), the role of imaging has considerably increased. Emergency imaging protocols should be done for rapid diagnosis of life-threatening injuries allowing simultaneous evaluation and resuscitation. Subsequent comprehensive imaging is essential to diagnose the often clinically missed injuries to reduce the overall morbidity. Imaging protocols must adapt to the patient's clinical scenario, which can be dynamically changing. Each trauma team should devise clear guidelines, protocols, and algorithms suitable for their center depending on the local availability of types of equipment and expertise. Radiologists must efficiently communicate and adopt patient-centered approach to ensure early appropriate care to these severely injured patients. Future research should involve multicentre studies to formulate the most appropriate imaging protocol in polytrauma to increase diagnostic accuracy and thereby reduce patient mortality.

Presence of preoperative Modic changes and severity of endplate damage score are independent risk factors for developing postoperative surgical site infection: a retrospective case-control study of 1124 patients.

PURPOSE: There is increasing evidence of an association between Modic changes (MC) and subclinical infection. However, the association of MC with postoperative surgical site infection (SSI) has not been adequately probed. This study primarily aimed to investigate a probable association between preoperative MC, total endplate damage score (TEPS), and SSI. METHODS: A retrospective analysis of 1124 patients who underwent surgery in a single institution (2016-2018) was performed, using both univariate and multiple logistic regression analyses to identify independent risk factors for SSI. RESULTS: The prevalence of SSI was 4% (44/1124 patients), with no association with age or sex. The prevalence of MC in the SSI group was significantly higher-79.54% (35/44) compared to 58.79% (635/1080) (p value = 0.006) in the control group with no specific relation to type or location of MC. A higher TEPS was associated with SSI (p value = 0.009). A receiver operating characteristic (ROC) curve for TEPS values to assess predictiveness of SSI showed TEPS ≥ 5.5 to have a better sensitivity of 84% than 72% for a TEPS ≥ 6.5. Univariate analysis showed TEPS > 6 (odds ratio 3.887) to have a stronger association with SSI than the presence of MC (odds ratio 2.725). Among various types of surgeries, discectomy had a higher association with SSI (p value = 0.03) when compared to fusion (p value = 0.071). However, multiple logistic regression analysis revealed only TEPS > 6, presence of MC and hypothyroidism as independent risk factors for SSI. CONCLUSION: Our data suggest that preoperative MC and TEPS > 6 are independent risk factors for developing surgical site infections. MC could be foci of chronic subclinical infection and not mere markers of degeneration, as initially described.

An Institutional Review of Tuberculosis Spine Mimics on MR Imaging: Cases of Mistaken Identity.

Although MRI has a spectrum of findings which help in the diagnosis of tuberculosis (TB) spine, a broad spectrum of spine pathologies resemble Pott's spine on MRI and are often missed due to inadequate clinical details. As a result, patients are often subject to unnecessary biopsy. A blinded radiologist may misdiagnose such mimic cases as TB. Our aim is to enable the reader to learn the main criteria that differentiate spine TB from other spine etiologies that mimic TB. A retrospective search was done and authors collected only MRI spine reports that showed a differential diagnosis or diagnosis of TB spine from the computer-based data records of the institution over a four-year period. This revealed 306 cases of TB spine out of which 78 cases with an alternate diagnosis that resembled TB spine were included. We describe a single institute review of 78 such cases that resemble and mimic Pott's spine on MRI. The cases being: (n = 15) pyogenic spondylitis, (n = 1) brucellar spondylodiscitis, (n = 12) rheumatoid arthritis, (n = 12) metastases, (n = 8) lymphoma, (n = 5) post-trauma fractures, (n = 10) degenerative disc disease, (n = 2) Baastrup's disease, (n = 9) osteoporotic fracture, (n = 3) spinal neuropathic arthritis, and (n = 1) case of Rosai-Dorfman disease. The clinical and radiological findings of all these cases were correlated with lab findings and histopathology wherever necessary. Appropriate recognition of these entities that resemble and mimic TB spine on MRI is important for optimal patient care. This paper exposes radiologists to a variety of spine pathologies for which biopsy is not indicated, and highlights key imaging findings of these entities to facilitate greater diagnostic accuracy in clinical practice.