Author/Authors :
Wagner, Ferdinand Institute of Health and Biomedical Innovation - Queensland University of Technology - Brisbane, Australia , Holzapfel, Boris M. Institute of Health and Biomedical Innovation - Queensland University of Technology - Brisbane, Australia , Maderbacher, G ̈unther Department of Orthopaedic Surgery for the University of Regensburg at the Asklepios Clinic Bad Abbach - Abbach, Germany , Matussek, Jan Department of Orthopaedic Surgery for the University of Regensburg at the Asklepios Clinic Bad Abbach - Abbach, Germany , Anders, Sven Department of Orthopaedic Surgery for the University of Regensburg at the Asklepios Clinic Bad Abbach - Abbach, Germany , Winkler, Sebastian Department of Orthopaedic Surgery for the University of Regensburg at the Asklepios Clinic Bad Abbach - Abbach, Germany , Grifka, Joachim Department of Orthopaedic Surgery for the University of Regensburg at the Asklepios Clinic Bad Abbach - Abbach, Germany , Keshmiri , Armin Department of Orthopaedic Surgery for the University of Regensburg at the Asklepios Clinic Bad Abbach - Abbach, Germany , Kammer, Birgit Pediatric Radiology - Department of Radiology, Dr. von Hauner Children’s Hospital - Ludwig-Maximilians-University - Lindwurmstrasse - Munich, Germany , Hubertus, Jochen Pediatric Radiology - Department of Radiology, Dr. von Hauner Children’s Hospital - Ludwig-Maximilians-University - Lindwurmstrasse - Munich, Germany
Abstract :
Patellar instability (PI) is a common finding in children. Current parameters describing patellofemoral jointalignment do not account for knee size. Additionally, most parameters utilize joint-crossing tibiofemoral landmarks and are proneto errors. )e aim of the present study was to develop a knee size-independent parameter that is suitable for pediatric or smallknees and determines the malpositioning of the distal patellar tendon insertion solely utilizing tibial landmarks.Methods. Sixty-one pediatric knees were included in the study. )e tibial tubercle posterior cruciate ligament distance (TTPCL) was measured viamagnetic resonance imaging (MRI). )e tibial head diameter (THD) was utilized as a parameter for knee size. An index wascalculated for the TTPCL and THD (TTPCL/THD). One-hundred adult knees were analyzed to correlate the data with anormalized cohort.Results. )e THD was significantly lower in healthy females than in males (69.3 mm±0.8 mm vs.79.1 mm±0.7 mm;p<0.001) and therefore was chosen to serve as a knee size parameter. However, no gender differences werefound for the TTPCL/THD index in the healthy adult study cohort. )e TTPCL/THD was significantly higher in adult PI patientsthan in the control group (0.301±0.007 vs. 0.270±0.007;p�0.005). )is finding was repeated in the PI group when the pediatriccohort was analyzed (0.316±0.008 vs. 0.288±0.010;p�0.033).Conclusion. )e TTPCL/THD index represents a novel knee size-independent measure describing malpositioning of the distal patellar tendon insertion determined solely by tibial landmarks
Keywords :
A Knee Size-Independent Parameter , Malalignment , Distal Patellofemoral Joint , Children
