title: The correlation between medial plica and trochlear dysplasis: An MRI study.
abstract: BACKGROUND
  Trochlear dysplasia is the most commonly encountered congenital etiologic factor of anterior knee pain.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the relationship between trochlear dysplasia with medial patellar plica as well as to investigate the distribution of plica types according to types of dysplasia.
  
  
  METHODS
  This is a retrospective case-control study.
  
  
  METHODS
  This study was conducted among 138 knee magnetic resonance imaging (MRI) scans. The presence of medial plica and its types were compared among 69 patients in whom trochlear dysplasia had been detected and 69 individuals with normal trochlear who were of the same age and gender as the patient group.
  
  
  METHODS
  Trochlear dysplasia and medial plica was compared by Chi-square with Yates correction and Fisher's exact probability tests (P< 0.001). The data were presented as mean, standard deviation, minimum-maximum, frequency, and percentage.
  
  
  RESULTS
  Of all the patients (n= 138), the number of patients in whom plica was observed wasn= 104 (75.3%), and the distribution of plica type was as follows:n= 70 (67.3%) Type 1,n= 25 (24%) Type 2, andn= 9 (8.6%) Type 3. Medial plica was more frequently observed in patients with trochlear dysplasia (P< 0.001). Type 2 and Type 3 medial plica were more frequently encountered in trochlear dysplasia (P< 0.001). Type 3 plica was not seen in patients with normal trochlea.
  
  
  CONCLUSIONS
  Medial patellar plica is more frequently seen in trochlear dysplasia. As the type of trochlear dysplasia progresses, the prevalence of thicker and shelf-shaped plica increases.
authors.affiliation: Department of Radiology, GOP Taksim Training and Research Hospital, İstanbul, Turkey.
authors.forename: Elif E
authors.initials: EE
authors.lastname: Ekin
authors.affiliation: Department of Radiology, GOP Taksim Training and Research Hospital, İstanbul, Turkey.
authors.forename: Hülya K
authors.initials: HK
authors.lastname: Yildiz
authors.affiliation: Department of Orthopaedics and Traumatology, GOP Taksim Training and Research Hospital, İstanbul, Turkey.
authors.forename: Harun
authors.initials: H
authors.lastname: Mutlu
authors.affiliation: Department Orthopaedics and Traumatology, Baltalimanı Education and Research Hospital, İstanbul, Turkey.
authors.forename: Engin
authors.initials: E
authors.lastname: Çetinkaya
keywords: Knee; medial plica; trochlear dysplasia