Study On Morphometrical Measurements Of Resected Surface Of Femurs In Total Knee Arthroplasty Of Chinese

With the prolong of the average life expectancy of Chinese and the ageing of the population in urban areas, there is a significant growing trend in the rate of serious knee disease. Total knee arthroplasty (TKA) has been successful in relieving pain for patients with serious and advanced knee disease, so that they may resume their normal life and have a improved wellbeing. With a history of over 100 years, Total knee arthroplasty (TKA), is the most mature technology and the most widely applied up till now. Such surgeries as unicompartmental arthroplasty, artificial patellofemoral arthroplasty has not yet been widely accepted, Surgical indications are rather narrow. Currently TKA has been the focus of the study both at home and abroad. In-depth and extensive study on the anatomy of the knee, biomechanics, kinematics has been continuing with a view to further improve the prosthesis, design of surgical tools and the improvement of surgical technique , for a more reliable and excellent surgical results.At present, the wide clinical application of artificial knee joint prosthesis system is designed in accordance with anatomical characteristics of Europeans and Americans. It was found that there prosthesis mismatch problem, when a considerable number of Chinese people use the foreign joint replacement system due to the ethnic differences. In artificial knee surgery we often encounter such problems as: the size of the Femoral prosthesis models is larger than that of tibial prosthesis. Chinese people have low and flat front condyle and high back condyle. In the femoral side, though femoral AP may match, it often occurs that the bone cutting surface wont match satisfactorily. Besides the technical factors in surgery, the contributing factor is there is morphologic difference between femoral prosthesis designed of basis of Western anatomical characteristics and the Osteotomy of the distal femur of the Chinese. There might be mismatch between implant and resected surface of femurs when the knee prosthesis design system designed on basis of Western anatomical characteristics is adopted in the TKA surgery for Chinese people.In order to design the artificial knee joint more in line with Chinese anatomical characteristics, reduce the incidence of postoperative complications and improve surgical results, we have done Study on Morphometrical measurements of resected surface of femurs of a certain number of corpses and Study on Morphometrical measurements of resected surface of femurs in Total Knee Arthroplasty of a larger sample size. An analysis of the testing findings in the surgery and the corpses was conducted afterwards, which may provide reference data for implant design.Purposeresearch on the morphological characteristics of resected surface of femurs of Chinese knee. Obtain precise data about relevant parameters about resected surface of femurs. Analyze internal relations among femoral anterior-posterior length, femoral medial-lateral width and femoral aspect rate of resected surface of femurs. Provide reference for establishing database of Chinese knee.Methodology1. subjects: select 60 fresh knee joints from Chinese corpses and randomly select 90 patients who come to Changzheng Orthopedic for TKA surgery2.divide corpses measurement group and surgery measurement group into three groups according to the height respectively 151—160cm, 161—170cm, 171—180cm) . corpses measurement group: 10 male and 10 female subjects in each group with a total of 60 subject. The average age ranges from 62.25±12.22 and average height is 164.42±8.39mm; surgery measurement group: 15 male and 15 female subjects in each group with a total of 90 subject. The average age ranges from 65.77±9.79mm and average height is 165.20±8.37mm3. The methodology of TKA is observed in the corpses measurement and surgery measurement observe. Resected surface of femurs is obtained. Such Precision Measuring Tools as Vernier caliper are used to measure femoral anterior-posterior length and femoral medial-lateral width and date is precisely recorded. femoral aspect rate is calculated;4. The data is presented by x|-±s and processed through SPSS 13.0 and SAS 8.0for Regression Analysis,Analysis of variance and T test. A p value of <0.05 indicated a significant effect. An analysis of the impact of sex, age and height on femoral anterior-posterior length, femoral medial-lateral width and femoral aspect rate of resected surface of femurs and the inner law among femoral anterior-posterior length, femoral medial-lateral width and femoral aspect rate of resected surface of femurs are conducted.Results1 . In the corpses measurement the femoral anterior-posterior length is 58.21±7.54mm; femoral medial-lateral width is 71.27±7.12mm; femoral aspect rate is 123.39±12.13%; in the surgery measurement, femoral anterior-posterior length is 57.96±6.83mm; femoral medial-lateral width is 70.48±6.72mm; femoral aspect rate is 122.22±9.56%;2. The Multiple regression analysis shows that, both in the corpses measurement and the surgery measurement, sex and age have no impact on femoral anterior-posterior length, femoral medial-lateral width and femoral aspect rate of resected surface of femurs, while height has a statistically significant effect on femoral anterior-posterior length, femoral medial-lateral width and femoral aspect rate of resected surface of femurs.3. The Related test of femoral anterior-posterior length, femoral medial-lateral width and femoral aspect rate of resected surface of femurs shows that in the corpses measurement there is linear relationship between femoral anterior-posterior length and femoral medial-lateral width, femoral anterior-posterior length and femoral medial-lateral width is positively correlative both in male and female subjects, there is linear relationship between femoral anterior-posterior length and femoral aspect rate, and femoral anterior-posterior length and femoral aspect rate is negatively correlative both in male and female subjects. It cannot be proved that there is linear relationship between male femoral medial-lateral width and femoral aspect rate, or there is a positive correlation between female femoral medial-lateral width and femoral aspect rate. In the surgery measurement there is linear relationship between femoral anterior-posterior length and femoral medial-lateral width , femoral anterior-posterior length and femoral medial-lateral width is positively correlative both in male and female subjects, there is linear relationship between femoral anterior-posterior length and femoral aspect rate and femoral anterior-posterior length and femoral aspect rate is negatively correlative both in male and female subjects. It cannot be proved that there is linear relationship between femoral medial-lateral width and femoral aspect rate;4. The Completely random analysis of variance test of the results in the corpses measurement and the surgery measurement shows that findings of cadavers and surgery are consistent.ConclusionThere is an increase in femoral anterior-posterior length and femoral medial-lateral width, yet a decrease in femoral aspect rate with the increase of the height in Chinese. The testing findings show that femoral aspect rate of the Chinese is larger than that of the Western people, which means that Chinese use smaller femoral implant compared with western people in TKA surgery. In another words, there is a mismatch between the implant and the characteristics of the Chinese resected surface of femurs. So the Chinese knee anatomic characteristics should be taken into account in the design of Prosthesis.