title: Morphology of proximal tibia in Iranian population and its correlation with available prostheses.
abstract: BACKGROUND
  Total knee arthroplasty is a complex procedure aiming to relieve pain and improve function. It is critical to select prosthesis that best cover the bone surfaces. Ethnicity may affect fitness of the components mainly designed for Caucasian populations. This study aimed to evaluate morphometric features of proximal tibia in Iranian population.
  
  
  METHODS
  During 2013, 150 consecutive patients (96 males and 54 females) form orthopedics department of Rasoul-Akram hospital with knee CT scan were randomly enrolled. We entered cases with apparent normal extremity alignment and bone maturity. Cases with history of fracture or conditions affecting knee profile were excluded. Standard cuts were simulated on CT scan. Anteroposterior (AP), mediolateral (ML) and aspect ratio (ML/AP) were measured for general morphology. Medial and lateral AP distance of tibia and their distance to tibial center were measured for checking symmetry.
  
  
  RESULTS
  Mean age was 43.0± 10.4 years (rang 11-80). Males showed significantly larger values in ML dimension and aspect ratio than females under a given AP value (p<0.001). However, the aspect ratio was suggestive of similar configuration of proximal tibia profiles among genders. Totally, close correlations were observed among simulated cuts and size-matched tibial components of the prostheses. However, better coverage was provided by some brands via designing interchangeable components for a given dimension. Medial and lateral condyles of tibia were almost symmetrical.
  
  
  CONCLUSIONS
  Our findings indicated that some alterations in the shape of the components are needed to provide optimal coverage in Iranian population. We propose symmetrical configuration in designing tibial components as well.
authors.affiliation: MD, Associate Professor of Orthopedics, Department of Orthopedic Surgery, Rasoul-e-Akram Hospital, Iran University of Medical Sciences, Tehran, Iran. mmoghtadaei@gmail.com.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Moghtadaei
authors.affiliation: MD, Orthopedic Surgeon, Department of Orthopedic Surgery, Rasoul-e-Akram Hospital, Iran University of Medical Sciences, Tehran, Iran. moghimi_javad@yahoo.com.
authors.forename: Javad
authors.initials: J
authors.lastname: Moghimi
authors.affiliation: MD, Professor of Orthopedics, Department of Orthopedic Surgery, Rasoul-e-Akram Hospital, Iran University of Medical Sciences, Tehran, Iran. dr.farahini@gmail.com.
authors.forename: Hossein
authors.initials: H
authors.lastname: Farahini
authors.affiliation: Orthopedic Surgeon, Clinical Fellow of the Knee Surgery, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran. Iran. a_jahansouz@yahoo.com.
authors.forename: Ali
authors.initials: A
authors.lastname: Jahansouz
keywords: Iranian; Proximal tibia; Total knee arthroplasty; computed tomography; morphometry