Study of Anterior Tibial Laxity Using GNRBandreg; in Healthy Knees in Children Aged 8 to 15

Abstract

Introduction: The ruptures of the anterior cross ligament are increasing in the child. The risk of minuscular injury \n and premature arthrosis degradation, therefore, explain the evolution of ligamentoplasty in the growing child. The \n GnRB device is used in clinical practice in the preoperative evaluation of anterior cross ligament ruptures in adults \n and in the postoperative assessment of ligamentoplasties. The child has an evolutionary intrinsic peripheral laxity \nwith growth. \nThe objective of this study is to analyze anterior tibial translational physiology in a healthy population of children \n to obtain reference values and to assist in the analysis of the pre-or post-operative assessment of past cross \nligament ruptures in a growing child. \nMaterial and Methods: 60 children under the age of 15 were included in this monocentric prospective study \n conducted between November 2017 and April 2018. The inclusion criteria were: age between 8 and 15 years, no \n history of pathology or knee surgery, no muscular pathology. 30 girls and 30 boys, divided into three age groups \n8-10 years, 10-12 years and >12-15 years were included on a voluntary basis during an orthopedic consultation. \nA laximetry test by the GnrB device was carried out at various successive thrusts (134, 150 and 200 N). A \nStudent test was used for statistical analysis \nResults: The average age was of 11,21 years ± 2,14. The youngest children presented pains during the pushes \nof 200 N, leading to a stop of the test. The values of travel on the set of the children were respectively in 134 N, 150 N and 200 N of 7,01 mm ± 2,7 mm; 7,34 mm ± 2,59 mm and of 9,03 mm ± 2,57 mm. There was no significant difference between the left and right knees at each press (p=0, 09; 0,11 and 0,31). There was no significant difference between girls and boys. The values of three age groups for every push were compared. There is no \nsignificant difference in the travel neither between the groups >12-15 years old and 10-12 ans and 8-10 ans nor \nbetween the groups 10-12 ans and 8-10 ans. \nDiscussion: By comparing the results with the literature, the laxity at the child seems superior to the adult. The \n device GnRB is a technique for diagnosing rupture and postoperative evaluation of previous cruciate ligament \n rupture in adults with a valuable defined threshold. If the device GnRB is available for clinical practice in an 8-yearold \nchild, the presence of physiological relaxation must be considered when interpreting the results.