Clinical Application And Biomechnical Study Of Femoral Neck Preservation In Total Hip Replacement

Partâ… : Clinical application of femoral neck preservation in total hip replacement.Paper 1 The treatment of hip disease with femoral neck preservation in total hipreplacementObjective:To evaluate the clinical results of CFP prosthesis in total hip replacement..Methods:From march 2003 to april 2008 52 hip of 42 patients underwent total hip arthroplastywith preservation of femoral neck. The study group included 27 males and 15 females with anaverage age of 41 years from 17 to 65 years.10 patients underwent bilateral THA and 32patients one side. Operation time ,blood loss, average postoperative hospitalization ,Harris hipscore and operation related complications were analyzed.Results:The patients were followed up from 12 to 61 months with an average of 39 months.Theoperation time was 30-70 mins with an average of 45 mins. The blood loss was 70-200mlwith an average of 110ml. All the patients were ambulatory 5 days after surgery with the helpof a walker.None of infection ,dislocation,deep venous thrombosis,thigh pain and heterotopicossification happened. Harris hip score are 88-97 points with an average age of 93.2 points 3months after surgery.Conclusion:Total hip arthroplasty with preservation of femoral neck has the advantages of minimalinvasion,less blood loss, good biodynamic harmony ,excellent stability of the prosthetic hip,and less prosthesis wear. It can replace traditional total hip arthroplasty as a new option. Paper 2 Total hip replacement with femoral neck preservation for the treatment ofsub-capitated femoral neck fractureObjective:To evaluate the clinical results of CFP prosthesis in the treatment of sub-capitatedfemoral neck fracture.Methods:From march 2003 to may 2008, 12 hip of 12 patients underwent total hip arthroplastywith preservation of femoral neck. The study group included 8 males and 4 females with anaverage age of 50.4 years from 45 to 65 years.All patients underwent one side THA.Operation time ,blood loss, average postoperative hospitalization ,Harris hip score andoperation related complications were analyzed.Results:The patients were followed up from 29 to 50months with an average of 37 months.Theoperation time was 35-65 mins with an average of 46.5 min mins. The blood loss was 80-200mL with an average of 120 mL. All the patients were ambulatory 5 days after surgery with thehelp of a walker.None of infection ,dislocation,deep venous thrombosis,thigh pain andheterotopic ossification happened. Harris hip score are 86-97 points with an average age of93.3 points 3 months after surgery.Conclusion:Total hip arthroplasty with preservation of femoral neck has the advantages of goodbiodynamic harmony, excellent stability of the prosthetic hip, and less prosthesis wear.Itprolong the waiting time and provide good bone condition for the hip revision. It will be anew option for the treatment of sub-capitated femoral neck fracture. Partâ…¡: Construction of Three-dimensional Finite Element Model ofFemur Based on DICOM Data and its biomechanical significanceObjective:To introduce a way of quick and precise construction of the three-dimensional finiteelement femur model and provide a new method for the construction of femur model.Methods:Normal male human femur was used as specimen for CT scan to obtain configuration,three-dimensional finite element model of the femur was obtained using MIMICS andABQUS 6.8 software.Results:Based on DICOM data, the three-dimensional finite element model of femur wasconstructed more quickly and precisely. The models were divided into 38636 nodes, 201422units. The model include the parts of coetical and cancellous bone. The biomechanical testresults accords with the previous results,so the model objectively reflected the real femurarthroplasty shape and biomechanical behavior.Conclusion:The research provides a more simple and precise method forthe construction of femur model and improve the efficiency based on Dicom standard andMimics software. The model was accurate and can be used for the reaseach on biomechanicalbehavior of femur. Partâ…¢The FEA research of CFP Prosthesis in total hip replacementObjective:To analyze the stress distribution on the femur after the hip arthroplasty with CFPprosthesis and provide biomechanical evidence for the improvement of femoral neckpreservation anhroplasty.Methods:The patients with the preservation of femoral neck in total hip replacement was used forCT scan to obtain configuration data to construct the three-dimensional finite elementmodel.The model was simulated under the load of body weight,and me stress distribution onthe femoral part was calculated.Results:The stress mode of the femoral part did not change in total hip replacement with collumfemoris reserved. There was no stress shielding around the femur prosthesis. The stress of 1zone increases and the stress of 4 and 8 zone decrease in total hip replacement with collumfemoris reserved.Conclusion:The stress mode of the femoral part did not change in total hip replacement with collumfemoris reserved. There was no stress shielding at the proximal part of the femurprosthesis. Illustrate this brachypus, proximal fixed prosthesis is excellent on thebiomechanical performance.