Search Results (146)

Background/Objective: International recommendations exist for MRI evaluation of sacroiliac joints (SIJs) in adult spondylarthritis (SpA) and other joints in juvenile (J)SpA. However, consensus recommendations for MRI acquisition protocols for SIJs in JSpA are lacking. Our survey gathered information on current imaging practices on SIJ MRI and expert opinions about imaging protocols. Methods: A survey was sent to an international group of pediatric radiologists and rheumatologists. Participants were asked about practices regarding sequences/planes, use of contrast, and preferred sequences/planes for evaluating individual lesions. Results: There were 38 unique survey respondents (North America, n = 19; South America, n = 1; Europe, n = 12; Asia, n = 2; Australia, n = 2; unknown = 2) from 32 institutions with a median of 15 (range 3–32) years of experience. Most (93%) institutions use the 2nd sacral vertebral body posterior cortex to plan coronal oblique sequences; most perform these as non-fat-suppressed T1W and fluid-sensitive sequences for evaluation of damage and inflammation, respectively. Among the 84% of institutions performing small field-of-view imaging, all include a coronal oblique plane, and 78% also do an axial oblique plane. Of all institutions, 22% utilize gradient echo (GRE) sequences. Most respondents (79%) did not consider contrast necessary for evaluating SIJs. Conclusions: Areas of agreement for a consensus MRI protocol for SIJ evaluation in JSpA include using a non-contrast-enhanced protocol and the S2 vertebral body posterior cortex to plan coronal oblique sequences. Further international consensus is required concerning the optimal scan plane to prescribe for axial sequences and the incorporation of an erosion-specific sequence into standard protocols. Full article

Osteonecrosis can cause significant and chronic musculoskeletal morbidity in children and adolescents with sickle cell disease (SCD). Although the femoral head is most frequently affected, lesions can also occur in the humeral head, vertebral bodies, knees, and other joints. Progressive joint damage can result in chronic pain, impaired mobility, loss of function, and the need for surgical intervention at a young age. As survival continues to improve in SCD, the long-term burden of osteonecrosis is becoming increasingly important. This narrative review summarizes the current understanding of osteonecrosis in pediatric and adolescent SCD. We review its epidemiology, pathophysiology, clinical presentation, imaging findings, and management. Disease burden increases with age and is closely linked to markers of severe SCD, including frequent vaso-occlusive crises and acute chest syndrome. Full article

Background and Clincal significance: Esophageal squamous cell carcinoma (ESCC) classically presents with progressive dysphagia and weight loss, but atypical presentations may redirect the diagnostic workup before the esophageal primary is identified. We report a case illustrating the simultaneous convergence of three diagnostic pitfalls: absence of dysphagia, bone-predominant metastatic presentation initially managed as carcinoma of unknown primary (CUP), and negative p40 staining in a vertebral biopsy in a patient subsequently confirmed to have invasive mid-esophageal squamous cell carcinoma. CasePresentation: A 66-year-old African American man with dementia, active tobacco exposure, and prior alcohol use disorder presented with constipation, abdominal pain, melena, fever, nausea, vomiting, and progressive back pain. Dysphagia or odynophagia was not documented. CT of the abdomen and pelvis demonstrated diffuse lytic osseous metastases. During evaluation and palliation of symptomatic L2 disease, kyphoplasty and radiofrequency ablation were performed, and bilateral core biopsies showed poorly differentiated carcinoma that was AE1/AE3-positive but negative for p40, CK7, CK20, TTF-1, S100, GATA-3, PAX8, and NKX3.1, yielding an initial diagnosis of CUP. Subsequent chest CT revealed esophageal wall thickening with intraluminal debris. Esophagogastroduodenoscopy (EGD) identified a non-obstructive ulcerated mid-esophageal lesion, and biopsy confirmed invasive squamous cell carcinoma. Poor performance status precluded systemic therapy; palliative external-beam radiation was initiated after diagnosis but discontinued because of clinical deterioration, and the patient transitioned to hospice before passing several weeks after diagnosis. Melena is a gastrointestinal alarm feature, and the combination of gastrointestinal bleeding and an esophageal imaging abnormality warrants timely endoscopic evaluation even when dysphagia is not reported or the symptom history is unreliable. Negative p40 staining in a poorly differentiated, potentially decalcified bone specimen may reflect loss of lineage-marker expression, technical antigen degradation, or both. Tissue or plasma genomic profiling and emerging cell-free DNA methylation classifiers could complement the workup but would not replace direct biopsy of a radiographically suspicious esophageal lesion. Conclusions: In metastatic poorly differentiated carcinoma, lack of documented dysphagia should not exclude an esophageal primary, particularly in patients with cognitive impairment. A p40-negative bone biopsy does not rule out squamous lineage. Timely EGD and integrated clinicopathologic assessment are essential when clinical or imaging findings suggest esophageal involvement. Full article

To quantitatively describe changes in skeletal radiopharmaceutical uptake during a training program including swimming in horses with neck and back pain, eighteen showjumping horses with documented vertebral lesions were prospectively included in a training program composed of 4 weeks of ridden work and then 8 weeks combining swimming and ridden exercise. Previously published data on this cohort did not demonstrate any clear change in thoracolumbar mobility. Bone scintigraphy was performed at the 4th and 12th weeks. Radiopharmaceutical uptake was quantified in 205 regions of interest (ROIs) and normalized using a Z-score approach. For each ROI, a linear mixed-effects model was fitted to evaluate the effect of the time point (W4, W12) on the normalized radiopharmaceutical uptake with the horse as a random effect. Overall variation in normalized signal intensity (Z-score difference W12–W04) was small (mean < 0.001; range −0.28 to 0.24). Significant changes between time points were identified in 21 ROIs. Thirteen ROIs located in the axial skeleton showed a decreased radiopharmaceutical uptake, whereas eight ROIs located in the limbs, including the humeral tubercles on both lateral views, showed an increased uptake. During a 2-month training program including swimming, axial skeletal radiopharmaceutical uptake did not increase in this cohort of horses with neck and back pain. However, substantial interindividual variability in scintigraphic changes was observed. Further controlled studies are needed to confirm these preliminary results and to better explore the effects of swimming on horses with axial musculoskeletal disorders. Full article

Methylmalonate semialdehyde dehydrogenase deficiency (MMSDD; OMIM #614265) is an ultra-rare autosomal recessive metabolic disorder caused by mutations in the ALDH6A1 gene, characterized by multi-system involvement including skeletal abnormalities, hypotonia, and visual impairment. To elucidate its pathogenic mechanisms, we characterized ALDH6A1/Aldh6a1 conservation and function using complementary zebrafish and mouse experimental systems. Bioinformatic and phylogenetic analyses revealed strong conservation of Aldh6a1/aldh6a1 gene structure, protein sequence, functional domains, and mitochondrial targeting across vertebrates. Spatiotemporal profiling also demonstrated dynamic embryonic expression in zebrafish neural tube, somites, liver, and intestine, as well as in metabolically active and developmentally relevant tissues of mice, with patterns that correspond to known MMSDD lesion sites in humans. Functional disruption of Aldh6a1 in zebrafish induced dose-dependent developmental defects, including spinal curvature, tail coiling, pericardial edema, and reduced survival, which were partially rescued by exogenous mRNA, confirming phenotype specificity effects. These findings support a role for ALDH6A1 in mitochondrial metabolism during neurogenesis, myogenesis, and organogenesis. Collectively, this cross-species framework highlights ALDH6A1/Aldh6a1 as essential for vertebrate development, provides mechanistic insight into the multi-system heterogeneity of MMSDD, and establishes a scalable platform for therapeutic discovery and precision intervention. Full article

Citrobacter freundii, an opportunistic Gram-negative bacterium belonging to the Enterobacteriaceae family, is emerging as a significant pathogen in diverse aquatic species, often associated with environmental stress and poor husbandry conditions. This study describes four distinct cases of fatal C. freundii-associated lesions in captive freshwater species in South Korea, including an Ocellate river stingray (Potamotrygon motoro), a Royal peacock bass (Cichla intermedia), a Japanese eel (Anguilla japonica), and a Poison dart frog (Dendrobates leucomelas). Bacterial DNA was analyzed using 16S rRNA PCR and sequence analysis, and FFPE tissues were additionally examined by PCR for molecular identification. Tissues were examined using routine hematoxylin and eosin (H&E) staining for detailed histopathology. Results: Molecular analysis detected C. freundii-associated DNA in the liver, kidney, and intestine of all samples. Histopathology consistently revealed severe bacterial enteritis with epithelial necrosis and abundant intraluminal bacterial aggregates (stingray, frog). Systemic manifestations included severe ulcerative skin lesions (peacock bass), hepatic fatty degeneration (peacock bass, eel), renal tubular degeneration (peacock bass), and prominent hepatic melanomacrophage center activation (frog); however, these findings should be interpreted as lesions observed in association with C. freundii detection, as several of these changes are not specific to bacterial infection. To our knowledge, this study provides one of the first comparative histopathological descriptions of naturally occurring C. freundii-associated cases across multiple captive freshwater vertebrate species in South Korea. Although bacterial culture, biochemical identification, and experimental infection were not performed, this retrospective investigation identified an association between molecular detection of C. freundii and histopathological lesions. Therefore, these findings should be interpreted as supportive diagnostic evidence rather than proof of a definitive causal relationship. These observations highlight the complementary value of histopathological examination alongside molecular detection in the diagnostic evaluation of aquatic animal diseases. Full article

Background and Clinical Significance: Marfan syndrome (MFS) is an autosomal-dominant connective-tissue disorder caused by pathogenic FBN1 variants. Aortic-root dilation and dissection are the canonical complications, whereas spontaneous vertebral artery dissection (VAD) is described only sporadically. Yet, cerebrovascular events are several-fold more common in MFS, and up to 74% of patients exhibit increased vertebral artery tortuosity, a validated predictor of dissection; Case Presentation: A 32-year-old African man with hypertension, type 2 diabetes mellitus, tobacco use, and headaches labelled as migraine presented with acute agitation, visual disturbance, vertigo, dysarthria, and right-sided weakness of two hours’ duration. Examination disclosed previously unrecognised marfanoid stigmata: arachnodactyly with positive wrist and thumb signs, reduced upper-to-lower segment ratio, increased arm-span-to-height ratio, dolichocephaly, pectus excavatum, and a high-arched palate. Non-contrast CT showed left occipital and posterior inferior cerebellar hypodensities. CT angiography demonstrated discontinuous intraluminal filling defects in the left vertebral artery at C4 and C2, and MR angiography confirmed long-segment occlusion/stenosis of the intracranial left vertebral artery. Echocardiography revealed mild aortic-root dilation (4.0 cm; Z-score +2.53) and a small patent foramen ovale (PFO) with a positive bubble study. The patient received intravenous thrombolysis followed by antiplatelet therapy, a high-intensity statin, antihypertensive therapy, and intensified glycaemic control. Because the infarct territory matched the dissected vessel and the small PFO carried no high-risk features (RoPE score 6; PASCAL category “unlikely”), VAD was designated the culprit lesion and the PFO incidental; Conclusions: Spontaneous VAD may be the inaugural manifestation of unrecognised MFS, antedating aortic complications. In young adults with cryptogenic posterior-circulation stroke and marfanoid features, early cervical imaging and Ghent assessment are warranted, and a coexistent PFO should not be assumed causal. Multidisciplinary evaluation supports accurate attribution and surveillance. Full article

[¹⁸F]-PSMA PET/CT is a high-impact modality for the staging and restaging of prostate cancer, but its wide anatomic coverage and tracer biology generate frequent incidental findings on both PET and the accompanying low-dose CT (LDCT). This narrative review is restricted in scope to fluorine-18 PSMA tracers because tracer-specific biodistribution and pitfall profiles shape what is perceived as incidentaloma: how confidently lesions can be categorized, and how often borderline findings trigger downstream testing, particularly for skeletal foci with [¹⁸F]-PSMA-1007. Specifically, [¹⁸F]-PSMA-1007 shows substantially higher rates of focal unspecific bone uptake than [⁶⁸Ga]-PSMA-11—reported in multicenter studies as affecting up to 40–50% of patients—which directly inflates the pool of potential incidentalomas and creates a tracer-specific false-positive problem with no parallel in gallium-68 practice. Additionally, [¹⁸F]-DCFPyL has different urinary clearance kinetics that affect bladder and ureteral uptake patterns, altering what qualifies as physiologic versus incidental in the pelvis. These differences mean that the threshold for Category B versus C classification—and the appropriate cascade-resistant language—must be tuned to the specific tracer in use. A framework built on [⁶⁸Ga]-PSMA-11 data would systematically underestimate bone pitfall frequency in [¹⁸F]-PSMA-1007 practice and could therefore paradoxically increase rather than reduce cascades if applied uncritically across tracers. These biodistribution differences have direct and concrete consequences for reporting behaviour and downstream management. In [¹⁸F]-PSMA-1007 practice, a focal bone uptake without a CT correlate in a mechanically plausible location—such as an anterior rib or vertebral endplate—should trigger Category B language in the report conclusion: the finding is documented in the body with explicit safety netting (“most consistent with unspecific uptake; no routine workup unless interval growth, new pain, or aggressive CT morphology”), and no referral to bone scintigraphy or MRI is generated. Without tracer-specific awareness, the same finding would typically prompt a reflex bone scan or whole-body MRI referral, delaying definitive prostate cancer management by weeks and adding imaging costs without diagnostic gain. By contrast, in [⁶⁸Ga]-PSMA-11 practice, an equivalent focal bone uptake without a CT correlate carries a higher prior probability of true metastatic disease given the lower background rate of unspecific uptake and should more often be reported at Category B with a lower threshold for escalation or more cautious language. For [¹⁸F]-DCFPyL, the higher urinary activity in the pelvis means that ureteral segments can mimic lymph node disease; recognizing this as a physiologic variant (Category C) rather than an equivocal nodal finding (Category B) avoids unnecessary pelvic MRI referrals that would otherwise be triggered by an uncontextualized report. In practical terms, the tracer-specific calibration of the overlay therefore changes not only the category assigned but also the specific safety-netting language and the escalation trigger, which directly modifies the downstream management pathway for each affected finding type. The scanned population—predominantly older men with a high prevalence of degenerative, inflammatory, and vascular abnormalities—creates substantial background noise that can drive low-value diagnostic cascades if incidental findings are communicated without actionability context. We integrate society-endorsed frameworks (EANM/SNMMI procedure guideline 2.0; E-PSMA; PSMA-RADS; and PROMISE/miTNM with miPSMA score) and propose a cascade-aware overlay for incidental findings that can be appended to existing PSMA reporting standards rather than replacing them. The A/B/C actionability overlay is a structured expert-consensus framework informed by existing evidence-based guidelines for specific finding types and by tracer-specific cohort data; it has not yet been prospectively validated as a standalone tool, and its current level of evidence is therefore analogous to a structured expert recommendation rather than an evidence-based clinical guideline. We operationalize a three-tier actionability scheme across PET- and CT-dominant findings, provide cascade-resistant language for conclusions, and clarify why SUVmax-only “probability scales” for lymph nodes are not recommended in routine reports. Three practical tables summarize PET incidental findings, lymph node reporting frameworks, and LDCT incidental findings, and two structured report templates are provided (concise and extended), with the extended version explicitly labelling actionability tiers and escalation triggers. Finally, we outline concrete AI use cases for standardization and triage while emphasizing governance to avoid the amplification of false positives and paradoxical growth of cascades. Full article

Background: Cervical osteochondromas invading the vertebral canal are rare but may cause spinal cord compression requiring surgical resection. Conventional open laminectomy may disrupt posterior stabilizing structures and potentially increase the risk of postoperative cervical deformity. This technical note describes a contralateral-structure-preserving endoscopic technique for cervical osteochondroma resection. Methods: A 25-year-old man with multiple hereditary exostosis presented with neck pain, mild numbness, and a positive Lhermitte’s sign. Computed tomography and magnetic resonance imaging revealed a 9 × 6 × 10 mm osteochondroma originating from the base of the C3 spinous process and extending into the vertebral canal with spinal cord compression and cord signal change. Preoperative clinical assessment included a Visual Analog Scale (VAS) for neck pain of 6/10, a modified Japanese Orthopedic Association (mJOA) score of 16/18, a Neck Disability Index (NDI) of 30%, and Nurick grade 1. The lesion was treated using unilateral biportal endoscopic spine surgery through a partial unilateral laminectomy and sublaminar endoscopic corridor, aiming for en bloc resection while preserving the contralateral lamina, posterior ligamentous complex, and posterior tension band. Continuous intraoperative neurophysiological monitoring (SSEP and MEP) was used throughout the procedure. Results: The osteochondroma was completely resected en bloc using a diamond burr and Kerrison rongeur. Histopathological examination confirmed osteochondroma, and negative margins were identified without residual tumor. The patient’s symptoms resolved completely without postoperative complications, and he was discharged on postoperative day 3. At the 18-month clinical and radiological follow-up, the patient remained symptom-free, with VAS improved to 1–2/10, mJOA improved to 18/18, NDI improved to 4%, and Nurick grade improved to 0, with partial regression of the cord signal change and no evidence of tumor recurrence on follow-up imaging. Cervical lordosis was maintained at the immediate postoperative timepoint. Conclusions: Contralateral-structure-preserving endoscopic resection may represent a potential minimally invasive alternative to conventional wide laminectomy or fusion-based approaches in carefully selected cases of benign cervical osteochondroma. Larger comparative studies with long-term follow-up are required to confirm the potential biomechanical and clinical benefits of this approach. Full article

Indolent systemic mastocytosis (ISM) is an under-recognised cause of secondary osteoporosis, and skeletal fragility may be the only presenting feature, delaying diagnosis. We describe four adults referred to a tertiary endocrinology service for unexplained osteoporosis or low-trauma fractures, in whom systemic mastocytosis (SM) was identified during work-up. All had elevated basal serum tryptase (41.4–87.0 µg/L), bone-marrow biopsy showing atypical mast cells and the KIT D816V variant; cutaneous lesions were absent in every case. Three patients fulfilled WHO 2022 criteria for ISM. The fourth had coexistent JAK2 V617F-positive post-essential-thrombocythaemia myelofibrosis and was classified as SM with associated haematological neoplasm (SM-AHN); his mast cell clone (tryptase 43.7 µg/L; KIT D816V VAF 0.391%) behaved indolently and contributed clinically through osteoporosis alone, illustrating that an indolent mast cell component can be overlooked when a chronic myeloid neoplasm dominates the picture. Presentations ranged from an isolated low-energy L5 fracture in a 55-year-old man, to multiple vertebral compression fractures despite denosumab in a 71-year-old woman with primary hyperparathyroidism, to severe wasp-sting anaphylaxis in a 43-year-old man. After multidisciplinary review, all received intravenous zoledronic acid with vitamin D repletion; KIT-targeted therapy is under consideration in selected patients. Although causal inferences cannot be drawn from four retrospectively identified cases, the series illustrates how ISM may be missed in unexplained or treatment-refractory osteoporosis—particularly in younger men, those with prior severe anaphylaxis, and those fracturing on antiresorptive therapy—and supports combining basal serum tryptase with high-sensitivity peripheral-blood KIT D816V testing, in line with the WHO/ICC/AIM-ECNM 2022–2024 criteria. Prospective studies are needed. Full article

Introduction: The concomitant occurrence of myeloproliferative neoplasms (MPNs) and plasma cell dyscrasias is rare and presents significant diagnostic challenges. Accurate distinction between overlapping features is essential, particularly when bone marrow fibrosis (BMF) is present. Case Description: We report a 57-year-old female, with a 10-year history of thrombocytosis managed with antiplatelet therapy, who presented with anemia and severe lumbar pain. Bone marrow biopsy revealed marked fibrosis, and imaging revealed multiple vertebral lesions. Diagnostic workup identified features consistent with myelofibrosis (MF) and coexisting IgG-Kappa multiple myeloma (MM). Although the patient initially fulfilled WHO criteria for MF, the rapid resolution of fibrosis following first-line plasma-cell-directed therapy suggested a secondary, cytokine-mediated process rather than a true concomitant MPN. Conclusions: This case highlights the importance of an integrated diagnostic approach in patients with overlapping features of hematologic malignancies. Differentiating between MM-associated fibrosis and true concurrent MPN and MM is critical, as misclassification may alter both prognosis and therapeutic strategy. In triple-negative cases, the histologic response to plasma-cell-directed therapy can serve as a key discriminating criterion. Awareness of the potential association between MM with fibrosis and extramedullary disease is also essential for clinical management. This case underscores the importance of an integrated diagnostic approach in patients with overlapping hematologic features. Full article

Background: The rising incidence of vertebral body fractures, vertebral infections and metastatic disease increases the need for diagnostic modalities with high specificity. Biopsy remains essential, yet comparative data on CT-guided versus intraoperative percutaneous fluoroscopy-guided biopsy are limited. Methods: This retrospective study compared two cohorts biopsied for spinal lesions between April 2015 and April 2024: CT-guided biopsy (n = 62), and intraoperative percutaneous biopsy (n = 154). Groups were analyzed for demographic and clinical characteristics, and diagnostic yield was defined by the conclusiveness of the primary biopsy; statistical comparisons were performed using Fisher’s exact test. Results: CT-guided biopsy yielded conclusive results in 46 of 62 cases (74.2%), whereas intraoperative, fluoroscopy-guided biopsy was conclusive in 41 of 154 cases (26.6%), representing a statistically significant difference (p < 0.001). In analogy, propensity score matching (1:1) resulted in similar significant (p < 0.001) results (CT-guided group vs. intraoperative, fluoroscopy-guided group: 86.7% vs. 35.6%) Conclusions: CT-guided biopsy demonstrated a substantially higher rate of conclusive results compared with intraoperative biopsy in this cohort. Further studies with larger and more balanced cohorts are needed to strengthen clinical recommendations. Full article

Spinal epidural empyema (SEE) is an uncommon but potentially severe cause of spinal cord compression and neurological dysfunction in veterinary patients. Bite wounds involving the vertebral column may result in deep tissue contamination, paraspinal abscessation, and secondary epidural infection; however, such injuries are poorly described in wildlife species. We report a case of SEE associated with chronically infected bite wounds in an adult Indian crested porcupine (Hystrix indica) with paraplegia. Physical and neurological examinations revealed exudative paravertebral wounds, paraplegia with preserved nociception, and findings consistent with a thoracolumbar spinal cord lesion. Survey radiography and contrast myelography demonstrated an extradural compressive lesion at L1–L2. Surgical exploration revealed a purulent tract extending from the skin and paraspinal tissues into the vertebral canal, and a left L1–L2 hemilaminectomy was performed with drainage, debridement, lavage, and Penrose drain placement. Staphylococcus aureus was isolated from the abscess, and antimicrobial therapy was adjusted based on susceptibility testing. Postoperative management included physiotherapy and environmental modifications to support ambulation. The porcupine regained ambulation within 4 days after surgery and was released back into the wild approximately 50 days postoperatively with normal gait and tail-rattling behaviour. This case highlights bite-wound-associated SEE as an important differential diagnosis in porcupines presenting with paraplegia and draining paraspinal wounds and suggests that surgical decompression combined with prolonged culture-guided antimicrobial therapy and environmental modifications may result in a favourable outcome. Full article

Background/Objectives: Stereotactic body radiation therapy (SBRT) provides improved pain response and local control for spinal metastases. However, management of local failure after initial SBRT is challenging. We report institutional outcomes, dosimetry, and toxicity for reSBRT following SBRT. Methods: We retrospectively reviewed 61 lesions (55 patients) treated with reSBRT after prior SBRT. Both SBRT courses delivered a median dose of 27 Gy. Patients underwent clinical and radiological evaluation every three months. Toxicity was graded using CTCAE v5.0. Dosimetric parameters for the spinal cord (SC), cauda equina (CE), planning organ-at-risk volumes (PRV), and thecal sac were converted to equivalent dose in 2 Gy fractions (EQD₂) using the linear–quadratic model (α/β = 2). Results: Median follow-up was 10.3 months. Forty lesions (65%) were cervicothoracic and 21 (35%) were lumbosacral. One- and two-year overall survival (OS) were 45% and 29%, respectively, and one- and two-year local control (LC) were 89% and 88%, respectively. Gastrointestinal primary tumors were associated with inferior LC (HR 2.41, 95% CI 1.11–5.23, p = 0.026). Fifteen patients (27%) reported myelitis/neuropathic symptoms during follow-up; four (7%) developed new post-radiation myelitis or neuropathy (RMN) without radiologic progression. Five patients (9%) developed vertebral compression fractures (VCF). Cumulative EQD₂ was not significantly associated with RMN (p = 0.344); all affected patients had thecal sac EQD₂ > 95.5 Gy and relevant nerve roots EQD₂ > 108 Gy. Conclusions: ReSBRT provided a favorable LC with acceptable toxicity. High cumulative dose to the thecal sac and nerve roots may contribute to neurologic toxicity as peripheral nerve injury. Full article

Background and Clinical Significance: Immunoglobulin G4-related disease (IgG4-RD) is a systemic immune-mediated fibroinflammatory disorder that can mimic infection or malignancy. Spinal involvement is exceedingly rare and usually limited to pachymeningitis or epidural pseudotumors. True vertebral bone destruction has been reported only sporadically. Case Presentation: A 54-year-old man presented to our emergency department with severe neck pain after a fall. CT and MRI revealed extensive osteolysis of the C1 posterior arch and odontoid process with atlantoaxial subluxation. Following a second inpatient fall, he developed acute tetraparesis. Emergency posterior occipitocervical fusion (C0–C4) with C1–C2 laminectomy and foramen magnum decompression was performed. Histopathology demonstrated dense lymphoplasmacytic infiltration and fibrosis with up to 36 IgG4⁺ plasma cells per high-power field and an IgG4⁺/IgG ratio > 40%, confirming IgG4-RD. The patient recovered substantial motor function postoperatively and regained independent ambulation after neurological rehabilitation. Conclusions: IgG4-RD can rarely present as destructive craniovertebral osteolysis with neurological compromise. Unexplained C1–C2 osteolytic lesions should prompt evaluation for IgG4-RD, a rare but treatable cause of cervical instability. Full article