title: Prediction of flexor tendon graft diameter in reconstruction of the anterior cruciate ligament by means of magnetic resonance imaging.
abstract: OBJECTIVE
  To evaluate the diameter of the flexor tendons in preoperative magnetic resonance imaging (MRI) examinations and compare this with the diameter of the graft obtained intraoperatively.
  
  
  METHODS
  This was a retrospective longitudinal epidemiological study. Forty-four patients were eligible for the study and their MRI examinations and surgical data were evaluated. The tendons were measured on MRI across their largest diameter in the axial plane, using the medial epicondyle of the femur as the slice level. In the surgery, routine graft preparation was performed, consisting of folding the gracilis and semitendinosus tendons to form a four-strand graft. Its measurement was recorded.
  
  
  RESULTS
  To evaluate the association between the variables, Pearson's correlation coefficient was estimated. A significant correlation was found between the measurements of the gracilis and semitendinosus tendons and the final diameter of the graft (p < 0.001). A ROC curve was fitted to the sum of the tendon diameters in order to determine a cutoff point associated with the graft diameter (≤8 mm or >8 mm). If the sum was greater than 5.28 mm, the chance of obtaining a graft larger than 8 mm would be 75%.
  
  
  CONCLUSIONS
  Measurement of the diameters of the gracilis and semitendinosus tendons through a preoperative MRI examination is a simple and effective way to predict the final size of the graft to be used in ACL reconstruction surgery.
authors: Pontifícia Universidade Católica do Paraná (PUC-PR), Hospital Universitário Cajuru, Curitiba, PR, Brazil.
authors: Fabiano
authors: F
authors: Kupczik
authors: Pontifícia Universidade Católica do Paraná (PUC-PR), Hospital Universitário Cajuru, Curitiba, PR, Brazil.
authors: Luiz Otávio Bombonatto
authors: LO
authors: Tauscheck
authors: Pontifícia Universidade Católica do Paraná (PUC-PR), Hospital Universitário Cajuru, Curitiba, PR, Brazil.
authors: Marlus Eduardo Gunia
authors: ME
authors: Schiavon
authors: Pontifícia Universidade Católica do Paraná (PUC-PR), Hospital Universitário Cajuru, Curitiba, PR, Brazil.
authors: Bruno
authors: B
authors: Sbrissia
authors: Instituto de Joelho e Ombro, Curitiba, PR, Brazil.
authors: Lucio Sergio Rocha
authors: LS
authors: Ernlund
authors: Pontifícia Universidade Católica do Paraná (PUC-PR), Hospital Universitário Cajuru, Curitiba, PR, Brazil.
authors: Ricardo Augusto Lass
authors: RA
authors: Alves
keywords: Anterior cruciate ligament; Anterior cruciate ligament reconstruction; Magnetic resonance spectroscopy; Orthopedic procedures