Evaluation of Odontoid Process Bone Quality with Hounsfield Unit Values in the Adult Population

Abstract

Objectives: In this study, the aim is to investigate the changes in bone density and quality of the odontoid tip, neck and second cervical vertebral body located beneath the base of odontoid with advancing age. Materials and Methods: Seven study groups were formed, each consisting of healthy individuals in the age ranges of 18-29, 30-39, 40-49, 50-59, 60-69, 70-79, and 80 years and above. The odontoid bone structure of each individual was identified on cervical computed tomography images in both sagittal and coronal planes. Mean Hounsfield unit (HU) values were calculated for the odontoid tip, odontoid neck, and the C2 body portion below the odontoid base areas in both midsagittal and midcoronal planes. The HU values were compared and analyzed. Results: There is a significant, negative correlation between age and the HU values measured in the sagittal plane for the odontoid tip, odontoid neck, and C2 vertebral body portion under the odontoid base (the correlation coefficients are -0.795 r, -0.766 r, and -0.789 r, respectively). Similarly, there is a significant, negative correlation between age and the HU values measured in the coronal plane for the odontoid tip, odontoid neck, and C2 vertebral body portion under the odontoid base (the correlation coefficients are -0.836 r, -0.680 r, and -0.802 r, respectively). These results indicate that as age increases, the quality of the odontoid bone decreases. Conclusion: The assessment of bone quality through computed tomography, based on HU values, reveals a significant decrease in the bone quality of both the odontoid bone and C2 vertebral body with increasing age.

Keywords

• Odontoid bone
• odontoid fractures
• Hounsfield unit

Erişkin Popülasyonda Hounsfield Ünitesi Değerleri ile Odontoid Proses Kemik Kalitesinin Değerlendirilmesi

Abstract

Amaç: İlerleyen yaş ile birlikte odontoid proses fraktürlerindeki artışın kemik kalitesinin zaman içinde azalması ile ilişkili olabileceği gösterilmektedir. Bu çalışmada, ilerleyen yaşla birlikte odontoid proses, boyun ve ikinci servikal vertebra gövdesindeki kemik yoğunluğu ve kalitesindeki değişikliklerin araştırılması amaçlanmıştır. Gereç ve Yöntem: Her biri 18-29, 30-39, 40-49, 50-59, 60-69, 70-79 ve 80 yaş ve üzeri sağlıklı bireylerden oluşan yedi çalışma grubu oluşturuldu. Her bireyin odontoid kemik yapısı bilgisayarlı tomografi görüntülerinde tanımlandı. Ortalama Hounsfield ünitesi (HU) değerleri odontoid proses, odontoid boynu ve C2 gövde kısmı için hem midsagittal hem de midkoronal planlarda hesaplandı. Elde edilen veriler söz konusu 7 grup arasında karşılaştırıldı ve istatistiksel olarak analiz edildi. Bulgular: Yaş ile odontoid proses, odontoid boynu ve C2 vertebra gövdesi kısmı için sagital düzlemde ölçülen HU değerleri arasında anlamlı, negatif bir korelasyon vardı (korelasyon katsayıları sırasıyla -0,795 r, -0,766 r ve -0,789 r’dir). Benzer şekilde, yaş ile odontoid ucu, odontoid boynu ve odontoid tabanının altındaki C2 vertebra gövdesi kısmı için koronal düzlemde ölçülen HU değerleri arasında anlamlı, negatif bir korelasyon vardı (korelasyon katsayıları sırasıyla -0,836 r, -0,680 r ve -0,802 r’dir). Bu sonuçlar, yaş arttıkça odontoid kemiğin kalitesinin azaldığını göstermektedir. Sonuç: HU değerlerine dayalı olarak bilgisayarlı tomografi ile kemik kalitesinin değerlendirilmesi, artan yaşla birlikte hem odontoid kemiğin hem de C2 vertebra gövdesinin kemik kalitesinde önemli bir düşüş olduğunu ortaya koymaktadır.

Keywords

• Odontoid kemik
• odontoid kırıklar
• Hounsfield ünitesi

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