“Crowned dens syndrome”（冠齿综合征）是一种较为罕见的口腔疾病，具体定义和临床表现可能因学术研究和临床实践的不同而有所差异。该术语首次被提出可能是为了描述与牙齿结构或周围组织异常相关的特定病例群。如果您对这一术语有更详细的信息需求，或者希望了解与之相关的医学研究或治疗方法，建议咨询口腔科医生或相关医学专家

《Spine Research》：Crowned dens syndrome

皇冠齿综合征（CDS）是急性颈椎疼痛伴环枕区钙化的临床综合征，本研究回顾性分析50例CT确诊CDS患者，发现52%有症状（女性占比73%，平均年龄71.34岁），治疗以NSAIDs或类固醇为主，症状缓解率达100%，但34.6%复发。影像学显示钙化多位于后侧（24%）及前侧（56%），CT为确诊金标准。

　　
Crowned dens syndrome (CDS) has emerged as a critical clinical entity in orthopedics and neurology, particularly given the rising aging population and diagnostic challenges. This syndrome, characterized by acute neck pain and peri-odontoid calcifications, was traditionally underestimated due to limited awareness among clinicians. A recent study conducted at Guangxi International Zhuang Medicine Hospital between 2019 and 2025 analyzed 50 CT-confirmed CDS cases to clarify its epidemiology, diagnostic nuances, and management efficacy.

Key findings reveal a significant gender and age discrepancy. Among 50 patients, 52% displayed symptoms like severe neck pain and restricted mobility, while 48% were asymptomatic despite visible calcifications. The female predominance (61% in symptomatic group vs. 50% in asymptomatic) and advanced age (71.34 years in symptomatic vs. 64.05 years in asymptomatic) highlight gender-specific vulnerabilities and age-related pathophysiological changes. Notably, older females with comorbidities such as hypertension or diabetes were disproportionately affected, suggesting interactions between degenerative processes and crystal deposition.

The study introduces a novel classification system distinguishing symptomatic and asymptomatic CDS. Symptomatic cases showed stronger correlations with structural abnormalities like atlantoaxial subluxation (18%) and foramen stenosis (22%), implying potential mechanical-chemical crosstalk between crystal deposition and spinal instability. Imaging analysis revealed calcifications distributed across anterior (56%), posterior (24%), lateral (14%), and circumferential (6%) odontoid regions, challenging previous assumptions about typical localization. The mean attenuation value of 561.5 HU significantly区别于常规骨密度（约1000 HU），为CT鉴别诊断提供新指标。

Clinical management strategies demonstrated strong efficacy against symptomatic cases. NSAIDs and corticosteroids achieved complete pain resolution in 100% of cases within 1-12 months, with recurrence rates at 34.6% over follow-up. This recurrence pattern underscores the importance of long-term monitoring and possibly addressing underlying crystal metabolic disorders. Notably, the absence of fever in symptomatic patients contradicts historical diagnostic criteria, emphasizing the need for updated clinical algorithms that prioritize imaging over inflammatory markers.

The study's methodological rigor includes multi-slice CT reconstruction with 3D visualization, which not only confirmed the crown-like calcification pattern but also quantified spatial relationships with the C1-C2 complex. This technical advancement reduced misdiagnosis risks with other entities like atlantoaxial subluxation or cervical spondylosis. However, limitations such as small sample size (n=50) and retrospective design necessitate cautious interpretation. The observed 9% rate of spinal cord compression on MRI without neurological deficits raises questions about the threshold for clinical intervention.

Pathophysiological insights from the research suggest CPPD crystal deposition in the transverse ligament and surrounding soft tissues as the primary mechanism. Inflammatory cascades triggered by crystal phagocytosis explain the acute pain and mobility restrictions, even though laboratory markers like CRP and ESR showed variable correlations. The study challenges traditional notions by showing that 31-year-old females can develop symptomatic CDS through occupational strain, expanding the demographic spectrum beyond typical elderly populations.

Clinical implications are substantial. First, CDS should be considered in patients presenting with acute neck pain and age >70, especially women. Second, noncontrast CT with 3D reconstruction is indispensable for diagnosis, as it distinguishes CDS from other spinal pathologies. Third, early NSAID therapy within 72 hours of symptom onset is crucial to prevent structural complications. Finally, the recurrence pattern suggests that while NSAIDs effectively manage acute symptoms, underlying crystal metabolic abnormalities require long-term attention.

The study's recommendation to implement CT screening protocols in elderly populations with neck pain could significantly improve diagnostic rates. For instance, the 19% initial misdiagnosis rate to neurology or rheumatology departments highlights the importance of orthopedic triage. The observed 65% prevalence of comorbidities like hypertension in symptomatic cases suggests that managing systemic risk factors may reduce CDS progression.

Future research directions identified include longitudinal tracking of crystal deposition dynamics, comparative studies between CPPD and hydroxyapatite deposition types, and investigation into hypomagnesemia's role in crystal formation. The discovery that 34.6% of patients experience symptom recurrence despite initial treatment success emphasizes the need for standardized protocols for follow-up imaging and therapeutic adjustments.

This work bridges the gap between radiological findings and clinical outcomes, establishing CDS as a distinct inflammatory crystal disease entity. The integration of imaging parameters (calcification distribution patterns, attenuation values) with clinical features provides a comprehensive diagnostic framework. Clinicians should maintain high suspicion for CDS in elderly female patients with acute cervico-occipital pain, even in the absence of fever, and adopt CT-based diagnostic protocols to prevent mismanagement. The observed treatment efficacy with NSAIDs supports current guidelines for crystal deposition diseases, while recurrence patterns warrant development of secondary prevention strategies.