October – December 2017/ Vol 3/ Issue 4 Print ISSN: 2456-9518, Online ISSN: 2455-5436 Original Research Article Surgical Update: International Journal of Surgery & Orthopedics Available online at: www.surgicalreview.in 175 | Page An epidemiological study to calculate angle between transepicondylar axis and posterior condylar axis of distal femur on MRI in Indian population Uikey S. 1 , Mehta S. 2 , Agrawal R. 3 , Goyal N. 4 1 Dr. Suresh Uikey, Assistant Professor, 2 Dr. Sonu Mehta, Senior Resident, Gandhi Medical College Bhopal, 3 Dr. Rahul Agrawal, Registrar, Fortis Hospital, Mulund, 4 Dr. Nikita Goyal, Lecturer, Sri Aurobindo Institute of Medical Science, Indore, MP, India. Corresponding Author: Dr. Sonu Mehta, Senior Resident, Gandhi Medical College Bhopal, Email: sonu_mehta1987@yahoo.com ………………………………………………………………………………………………………………………..................... Abstract Introduction: Rotational positioning of femoral component is a critical aspect of total knee arthroplasty and evaluation of the landmark for rotation of distal femur is a challenge. Most Orthopaedic Surgeons prefer to use more available posterior femoral condyle axis. Objectives: Aim of this study is to calculate the angle between TEA and PCA of distal femur on MRI in Indian population. This study is focused on the fact that angle between TEA and PCA may vary from 3 degrees and not fixed as most of the surgeons consider and most of the TKA implants are designed considering it fixed 3 degrees which can seriously affect the outcome and longevity of TKA. Method: In this study MRI KNEE of 152 patients were studied to calculate angle between TEA AND PCA of distal femur. Software called LEONARDO wasutilized to calculate the angle on MRI images. Results: Study shows the average angle of 4.54 degrees. No gender related disparity noted. No age-related increase or decrease of angle noted. In our study we found that, minimum angle between TEA and PCA is 2 degrees while maximum angle is 7.1 degrees. Conclusion: Based on our study and results we conclude that the average angle between TEA and PCA in Indian population is 4.54 degrees. Thus, further studies will be required to investigate the effect of this angle over rotational alignment of femoral component during TKA’s and its immediate and longtermoutcomes. Study proves the angle not fixed to 3 degrees and individualistic approach from case to case basis maybe beneficial. Key words: Epidemiological, arthroplasty, TEA. ………………………………………………………………………………………………………………………..................... Introduction Rotational positioning of femoral component is a critical aspect of total knee arthroplasty and evaluation of the landmark for rotation of distal femur is a challenge. Most Orthopaedic Surgeons prefer to use more available posterior femoral condyle axis, but other landmark especially surgical transepicondylar axis may be more valid. MRI scan helps to evaluate these landmarks more accurately. The purpose of our study was to ascertain the angle between transepicondylar axis and posterior condylar axis in Indian population on MRI scan. Most of the surgeons consider it as fixed 3 degrees of external rotation in all the cases but purpose of this study is to actually calculate it on MRI images of Indian population. As rotational alignment plays an immense role in TKA outcomes it is important to put the implant in geometrically anatomical position. The geometry of the proximal tibia and distal femur is intimately linked with the biomechanics of the tibio-femoral and patella-femoral joints [1]. Rotational positioning of femoral and tibial component is appeared as critical aspect of total knee arthroplasty (TKA). Since the consequences of mal rotation may produce patellofemoral problems, flexion instability, stiffness, and abnormal gait patterns [2,3]. Despite the current high success rate of TKA, patellofemoral complication remains one of common cause of revision surgeries[3]. Proper positioning of TKA components is vital for the functional outcome of the procedure. Although the desired positions and guiding landmarks for placement of the femoral and tibial components in the coronal and sagittal planes have been well defined, rotational positioning of the components might still be challenging [4]. Manuscript Received: 28 th November 2017 Reviewed: 7 th December 2017 Author Corrected: 14 th December 2017 Accepted for Publication: 20 th December 2017