PURPOSE: Proximal femoral fractures are among the most commonly sustained fractures. The current treatment of stable proximal femoral fractures located in trochanteric region primarily involves the use of two systems: extramedullary dynamic hip screws and intramedullary hip nails. Given that these fractures are mainly found in the elderly population, the necessity of a repeat, due to failure of the first, may jeopardize the patient's life. Decisive factors contributing to the healing of a fracture (or the failure thereof) include fracture pattern, technical implementation of the operation (i.e., position of the implant), implant's properties and its changes in relation to the surrounding bone tissue during loading. Each screw insertion variant results in damage to various load-bearing bone structures, which can be expected to influence healing quality and stability of newly formed bone. METHOD: With the aid of a numerical model and finite element methods, the authors analyzed several different positions of IMHN/PFH-nails in the proximal femur, with the objective of determining positions with an increased risk of failure. RESULTS AND CONCLUSION: In model situations, it has been shown that in stable fractures results do not depend on absolutely precise positioning and small deflections in the nails and neck screws positions do not significantly increase the risk of failure for the entire fixation. Damage to load-bearing structures relative to various implant placements does not impact the resultant overall fixation stability. Therefore, it is not necessary to re-introduce implants in the ideal position, which can lead to reduced patient radiation doses during surgery.

• Keywords
• Bone fixation, Complications, Finite element method analyses, Intramedullary hip nail, Stable pertrochanteric fracture,
• MeSH
• Finite Element Analysis MeSH
• Biomechanical Phenomena MeSH
• Femur injuries   surgery   MeSH
• Hip Fractures surgery   MeSH
• Fracture Fixation, Intramedullary instrumentation   methods   MeSH
• Bone Nails * MeSH
• Humans MeSH
• Treatment Failure MeSH
• Risk Factors MeSH
• Aged MeSH
• Models, Theoretical MeSH
• Weight-Bearing MeSH
• Check Tag
• Humans MeSH
• Aged MeSH
• Publication type
• Journal Article MeSH

PURPOSE: The purpose of our work was to verify the hypothesis that muscle insertions and ligament attachments have an impact on the course of typical break lines in the area of the trochanteric massif, i.e., to provide a more detailed description of the origins and insertions of the musculo-ligamentous apparatus on the surface of the proximal femur, and to find a potential morphological correlate between muscle insertions and ligament attachments to the proximal femur and the course of the break line in a typical pertrochanteric fracture. METHODS: A detailed dissection of areas of trochanter major et minor, linea et crista intertrochanterica was performed in 50 anatomical preparations of the proximal femur, and the insertions of the muscular-ligamentous structures were described. The set of 600 radiographs were used to obtain projections of typical break lines on the proximal femur, and corresponding areas of exposed bone surface were identified in the anatomical preparations based on the projections and on 15 real specimens of patients after the pertrochanteric fracture osteosynthesis. RESULTS AND CONCLUSION: Bone covered only with the periosteum, with no reinforcing elements of the origin or insertions of muscles or attachments of ligaments, represents the locus minoris resistentiae for beginning of fractures. Variability in the sizes and shapes of pertrochanteric fracture fragments also depends on variability of the locations and sizes of soft tissue attachment areas at specified sites on the proximal femur.

• MeSH
• Dissection MeSH
• Femoral Neck Fractures diagnostic imaging   surgery   MeSH
• Hip Fractures diagnostic imaging   surgery   MeSH
• Fracture Fixation, Intramedullary methods   MeSH
• Ligaments, Articular anatomy & histology   MeSH
• Muscle, Skeletal anatomy & histology   diagnostic imaging   MeSH
• Bone Nails MeSH
• Femur Neck anatomy & histology   MeSH
• Humans MeSH
• Cadaver MeSH
• Radiography MeSH
• Aged MeSH
• Sensitivity and Specificity MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH