N Bouguennec1, G A Odri2, N Graveleau3, P Colombet3. 1. Clinique chirurgicale traumatologique et orthopédique, CHU de Nantes, 1, place Alexis-Ricordeau, 44000 Nantes, France. Electronic address: nbouguennec@gmail.com. 2. Service de chirurgie orthopédique, CHR Orléans, 1, rue Porte-Madeleine, 45000 Orléans, France. 3. Clinique du sport de Bordeaux-Mérignac, 9, rue Jean-Moulin, 33700 Mérignac, France.
Abstract
BACKGROUND: TELOS™ is among the reference tools for the instrumental measurement of anterior tibial translation during the initial work-up and follow-up of patients with injuries to the anterior cruciate ligament (ACL). GRNB(®) is a non-irradiating but recently developed tool for which only limited data are available. HYPOTHESIS: The GRNB(®) offers better reproducibility than TELOS™ for measuring anterior tibial translation without rotation in normal knees. MATERIAL AND METHODS: We retrospectively evaluated instrumental laxity measurements in normal knees. Data were available for 60 TELOS™ measurements (9kg load) and 57 GNRB(®) measurements (89N and 134N loads). For each instrument, we compared the absolute variation in anterior tibial translation between two measurements performed 6 months apart. For each GNRB(®) measurement, patellar pressure was recorded. RESULTS: No significant differences were found between mean (± SD) variations in translation between the two instruments. A greater than 2.5mm variation between the two measurements was significantly more common with TELOS™ than with GRNB(®) (P<0.05, Chi(2) test). GRNB(®) translation values did not correlate with patellar pressure. DISCUSSION: The GNRB(®) device offers greater reproducibility than TELOS™ when used to quantitate anterior tibial translation. The limited sample size may have prevented the detection of a significant difference between mean values. In addition, disadvantages of the TELOS™ include radiation exposure of the patient, operator-dependency of measurements made on the radiographs, and absence of a biofeedback system to limit hamstring contraction. GNRB(®) does have hamstring contraction biofeedback control but uses another parameter, namely, patellar pressure, for which the optimal value is unknown. Quadriceps and hamstring co-contraction induced by excessive patellar pressure may influence anterior tibial translation. The optimal patellar pressure value needs to be determined.
BACKGROUND: TELOS™ is among the reference tools for the instrumental measurement of anterior tibial translation during the initial work-up and follow-up of patients with injuries to the anterior cruciate ligament (ACL). GRNB(®) is a non-irradiating but recently developed tool for which only limited data are available. HYPOTHESIS: The GRNB(®) offers better reproducibility than TELOS™ for measuring anterior tibial translation without rotation in normal knees. MATERIAL AND METHODS: We retrospectively evaluated instrumental laxity measurements in normal knees. Data were available for 60 TELOS™ measurements (9kg load) and 57 GNRB(®) measurements (89N and 134N loads). For each instrument, we compared the absolute variation in anterior tibial translation between two measurements performed 6 months apart. For each GNRB(®) measurement, patellar pressure was recorded. RESULTS: No significant differences were found between mean (± SD) variations in translation between the two instruments. A greater than 2.5mm variation between the two measurements was significantly more common with TELOS™ than with GRNB(®) (P<0.05, Chi(2) test). GRNB(®) translation values did not correlate with patellar pressure. DISCUSSION: The GNRB(®) device offers greater reproducibility than TELOS™ when used to quantitate anterior tibial translation. The limited sample size may have prevented the detection of a significant difference between mean values. In addition, disadvantages of the TELOS™ include radiation exposure of the patient, operator-dependency of measurements made on the radiographs, and absence of a biofeedback system to limit hamstring contraction. GNRB(®) does have hamstring contraction biofeedback control but uses another parameter, namely, patellar pressure, for which the optimal value is unknown. Quadriceps and hamstring co-contraction induced by excessive patellar pressure may influence anterior tibial translation. The optimal patellar pressure value needs to be determined.
Authors: Jerome Murgier; Jean Sebastien Béranger; Philippe Boisrenoult; Camille Steltzlen; Nicolas Pujol Journal: Int Orthop Date: 2018-02-02 Impact factor: 3.075
Authors: David Bade; Garrett Malayko; Liam Johnson; Kylie Bradford; Tristan Reddan; Chris Stockton; Kieran Frawley; Teresa Phillips; David Saxby; Robert S Ware; Joshua Byrnes; Christopher P Carty Journal: BMJ Open Date: 2022-08-19 Impact factor: 3.006