ÜLKÜ ÇÖMELEKOĞLU, HÜSEYİN MUTLU, SERAP YALIN, Selda BAĞIŞ, Altan YILDIZ, OYA ÖGENLER

Normal ve osteoporotik sıçan femurunda kemiğin biyomekanik kalitesinin biyomekanik testle ve sonlu elemanlar analizi ile belirlenmesi

Amaç: Bu çalışmada, normal ve osteoporotik sıçan kortikal femurunun biyomekanik özellikleri hem deneysel biyomekanik analiz hem de sonlu elemanlar analizi (SEA) ile değerlendirildi. Çalışma Planı: Ağırlıkları 225-250 gram arasında değişen 14 adet genç erişkin Sprague-Dawley cinsi dişi sıçan eşit sayıda iki gruba ayrıldı. Bir gruba ketamin anestezisi altında iki taraflı ovariektomi yapıldı. Ovariektomiden 14 hafta sonra, çift enerjili X ışınları absorbsiyometrisi ile tüm sıçanlarda kemik mineral yoğunluğu (KMY) ölçüldü; daha sonra yüksek dozda ketamin ile deneklerin yaşamı sonlandırılarak sağ ve sol femurları çıkarıldı. Sol femurlara biyomekanik germe testi uygulandı. Sağ femurlarda ise kortikal kemik kesiti bilgisayarlı tomografi ile görüntülendi, bilgisayara aktarılan görüntülerden kemiklerin üçboyutlu modelleri elde edildi. ANYSIS 9.0 paket programı kullanılarak SEA yapıldı. Her iki yöntemle elde edilen kemiklerin deformasyon, stres ve strain dağılımları karşılaştırıldı. Sonuçlar: Ovariektomi grubunda KMY değerinin kontrol grubuna göre yaklaşık %29 oranında azaldığı görüldü (p

Anahtar Kelimeler:

Hastalık modelleri, hayvan, Biyomekanik, Femur, Sıçan, Sprague-Dawley, Hayvanlar, Osteoporoz, Overektomi, Absorptiyometri, foton, Sonlu eleman analizi

Determining the biomechanical quality of normal and osteoporotic bones in rat femora through biomechanical test and finite element analysis

Objectives: This study aimed to determine the biomechanical quality of cortical bone in normal and osteoporotic rat femora with the use of biomechanical analysis and finite element analysis. Methods: Fourteen young adult female Sprague-Dawley rats weighing 225-250 g were randomized into two groups equal in number. One group underwent bilateral ovariectomy under ketamine anesthesia. Fourteen weeks after ovariectomy, bone mineral density was measured by dual energy X–ray absorptiometry in two groups and the rats were sacrificed under high-dose ketamine anesthesia for removal of all the femora. The right femora were subjected to biomechanical tension tests. In the left femora, cortical bone sections were visualized by computed tomography and finite element analysis was performed on computer-generated three dimensional images using the ANYSIS 9.0 software. Deformation, stress, and strain values obtained by the two analyses were compared. Results: Compared to the control group, bone mineral density decreased by 29%, and decreases in deformation, stress, and strain values were 39%, 51%, and 64%, respectively, in the ovariectomized rats (p<0.05). No significant differences were found between the results of biomechanical measurements and finite element analysis (p>0.05). Conclusion: Our data suggest that finite element analysis can be used in vivo to determine biomechanical quality of the bone in osteoporotic patients.

Keywords:

Disease Models, Animal, Biomechanics, Femur, Rats, Sprague-Dawley, Animals, Osteoporosis, Ovariectomy, Absorptiometry, Photon, Finite Element Analysis,

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