Ercan OLCAY, Ertuğrul ALLAHVERDI, TURGUT GÜLMEZ, Dilek Olgun ERDİKMEN, CELAL ŞAHİN ERMUTLU, Zihni MUTLU

Evaluation of the effects of holes of various sizes on fracture rates in sheep femurs

Uzun kemiklerdeki defektlerin patololojik kırığa neden olduğu bilinmektedir. Delikler özellikle torsiyonel güçlere maruz kalınca bükülme esnasında kemiği zayıflatır ve kırık riskini artırır. Buradaki çalışmamızda biz koyun femur kemiklerinde drille delinmiş çeşitli sayı ve boyutlardaki deliklerin etkilerini araştırdık. 96 tane taze koyun kemiği her biri ilaveten 3 kemiği içeren 4lü alt gruplara bölünerek 8 gruba ayrıldı. Her bir grubta 2 mmden 5.5 mmye kadar değişen 1den 4e kadar delikler femurlar delinerek açıldı ve kemikler rotasyon testine tabi tutuldular. Kırığa neden olan kuvvetler ve kuvvet eğrileri ölçüldü ve kayıt edildi. Delik açılan femurlarda kırık oluşturan deliklerin boyutları ve sayısının etkisi iki yönlü varyans analizi ve Tukeyin çoklu karşılaştırma testi ile mukayese edildi. P

Koyun femurlarında çeşitli boyutlardaki deliklerin kırık oranları üzerine etkilerinin değerlendirilmesi

Defects in long bones are known to lead to increased risk of pathologic fracture. Holes weaken bones and increase the risk of fracture during bending, especially on exposure to torsional forces. Here, we investigated the effect of holes of varying numbers and sizes drilled into sheep femur bones on the resistance of the bone to torsional forces. Ninety-six fresh sheep femur bones were allocated to 8 groups, which were further subdivided into 4 groups of 3 bones each. In each group, 1 to 4 holes ranging from 2 to 5.5 mm were drilled into the femurs, and the bones were subjected to a rotation test. Forces that caused fractures and the force curves were measured and recorded. The effect of the number and size of the holes drilled in the femurs on the occurrence of fractures was compared using two-way analysis of variance, and Tukeys multiple comparison test was used for multiple comparisons. P<0.05 was considered statistically significant. We found that the resistance of a bone to torsional forces decreased significantly with increase in the number and size of the drilled holes (P<0.001). The rate of fractures increased as the number and sizes of the holes increased. The resistance of the bones to torsional forces decreased as the number of holes increased. We showed that the size of a defect in a bone is extremely important for torsional resistance and is, in fact, more important than the number of defects.

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