Review of Diagnosis Value of Knee Joint Axial Compare to the Knee Joint Arthroscopy in Diagnosis of Patellofemoral Malalignment

Abstract

• Background: Every orthopedist everyday encounter with at least one patient with anterior knee pain and for further evaluation will request radiography, especially axial knee radiography. This descriptive study was planned to determine the sensitivity, specificity, positive predictive value and negative predictive value of axial knee view respect to arthroscopic finding, as gold standard technique for evaluation of patellofemoral malalingnment. • Methods: In convenient manner from 61 patients who was candidate for arthroscopy, irrespective to initial diagnosis, axial view was done and reported by radiologist and according to his report, patient was classified to lateral tilt positive, lateral subluxation positive or negative. Then, patellofemoral joint was studied arthroscopically from anterolateral portal to determine if central ridge of patella seat in trochlear groove before 450 of knee flexion or not? If seating was not occur 450 of knee flexion, the patella was consider arthroscopically positive for patellofemoral malalignment. Then radiographic findings, based on arthroscopic finding, were classified to true positive, true negative, false positive, false positive and false negative. • Finding: Sensitivity, specificity, positive predictive value and negative predictive value were 71%, 38%, 60% and 50%, respectively. Sensitivity and specificity of positive tilt axial view compare to arthroscopy were 56% and 41%, respectively. • Conclusion: Based on the results of this study, the most valuable diagnostic method for patellofemoral malalingnment was physical examination; however, axial view has good correlation to arthroscopy.

Keywords

• Patellofemoral malalignment
• Anterior knee pain
• Axial view
• Arthroscopy
• Chondromalacia of patella