Comparison of non-compression and compression interlocking intramedullary nailing in rabbit femoral shaft osteotomy model
Mehmet Emre Baki1, Cengiz Aldemir2, Fatih Duygun2, Ali Doğan2, Gökçen Kerimoğlu3
1Department of Orthopedics and Traumatology, Medical Faculty of Karadeniz Technical University, Trabzon Turkey
2Department of Orthopedics and Traumatology, Antalya Training and Research Hospital, Antalya, Turkey
3Department of Histology and Embryology, Medical Faculty of Karadeniz Technical University, Trabzon Turkey
Keywords: Femoral fracture; finite element analysis; intramedullary nail.
Objectives: This study aims to compare non-compression and compression intramedullary nailing in an experimental femoral shaft osteotomy model in terms of radiological, histological, and biomechanical aspects. Materials and methods: Twenty-four white New Zealand rabbits (average weight 4.3 kg; range 4 to 4.8 kg) were divided into three groups. A right femoral osteotomy was performed in all rabbits and all femurs were fixed with titanium compression interlocking intramedullary nail. After locking of nails, no compression was performed in group 1 while 0.5 mm and 1 mm compressions were performed in group 2 and 3, respectively. All rabbits were sacrificed four weeks after operation. Fracture sites were examined histologically and radiologically. Finite element analyses were performed.
Results: Radiological scores of groups 2 and 3 were significantly higher than group 1. There was no significant difference between groups 2 and 3 radiologically. Best histological scores were achieved in group 2. According to finite element analyses, osteotomy site in group 2 was exposed to 1240 N of load and 34.5 MPa of mean stress.
Conclusion: Compression interlocking intramedullary nailing provides faster fracture healing than non-compression interlocking intramedullary nailing. Best histological fracture healing scores were obtained with 0.5 mm compression performed at the fracture site.