Medical Imaging and Radiology

Medical Imaging and Radiology

ISSN 2054-1945
Original Research

Measurement of knee articulation laxity by videofluoroscopy image analysis: CINARTRO

Franco Simini1*, Dario Santos1,2,3, José Artigas1, Verónica Gigirey4, Luis Dibarboure4 and Luis Francescoli5

*Correspondence: Franco Simini

1. Núcleo de Ingeniería Biomédica, Facultades de Medicina e Ingeniería, Universidad de la República - Montevideo, Uruguay.

Author Affiliations

2. Departamento de Rehabilitación - Biomecánica Clínica, Hospital de Clínicas, Montevideo, Uruguay.

3. Escuela Universitaria de Tecnología Médica, Universidad de la República, Montevideo, Uruguay.

4. Departamento de Imagenología Clínica, Hospital de Clínicas, Montevideo Uruguay.

5. Clínica de Ortopedia y Traumatología, Facultad de Medicina, Montevideo Uruguay.


Several methods are used to evaluate knee articulation during movement, such as the Tibio Femoral Contact Point migration or the Instantaneous Centre of Rotation displacement and even the Moment Arm variations during extension. Such evaluation is important in case of Anterior Cruciate Ligament reconstruction or Total Knee Replacement, but unfortunately, it is only available in research settings. We have devised a novel clinical methodology based on serial images of knee movement videofluoroscopy, which are interactively analysed to allow automatic determination of kinematics parameters. The method, called CINARTRO, compares values with the contralateral knee and produces a standard Clinical Document Architecture file ready for Electronic Medical Record systems. To correct the “pin cushion” effect of X ray intensifiers, a 10 mm apart lead spheres phantom was developed. To validate the interactive selection of anatomical points, cadaver limbs were marked with lead markers and compared with points marked on the blind image. Anterior Cruciate Ligament (injured and reconstructed) and contralateral Moment Arms averages of 53mm, 39mm and 43mm respectively were found. Similarly the Total Knee Replacement patient`s Moment Arm was reduced to 33mm. These findings justify the use of our methodology to help clinicians during rehabilitation follow-up.

Keywords: Knee Kinematics, Tibio Femoral Contact Point, Quadriceps Moment Arm, Videofluoroscopy, CINARTRO

ISSN 2054-1945
Volume 5
Abstract Download