Knee joint kinematics with dynamic augmentation of primary anterior cruciate ligament repair - a biomechanical study

Abstract

BackgroundDynamic augmentation of anterior cruciate ligament tears seems to reduce anteroposterior knee translation close to the pre-injury level. The aim of the present study is to biomechanically investigate the course of translation during a simulated early post-operative phase. It is hypothesized that anteroposterior translation is maintained at the immediate post-operative level over a simulated rehabilitation period of 50’000 gait cycles.MethodsEight fresh-frozen human cadaveric knee joints from donors with a mean age of 35.5 (range 25–40) years were subjected to 50’000 cycles of 0°-70°-0° flexion-extension movements in a custom-made test setup. Anteroposterior translation was assessed with simulated Lachman/KT-1000 testing in 0°, 15°, 30°, 60° and 90° of flexion in knee joints treated with the novel technique initially and after 50’000 cycles testing. Statistical analysis was performed using the Wilcoxon Signed-Rank Test. The level of significance was set at p = 0.05.ResultsAnteroposterior translation changed non-significantly for all flexion angles between cycle 0 and 50’000 (p = 0.39 to p = 0.89), except for 30° flexion, where a significant increase by 1.4 mm was found (p = 0.03).ConclusionIncrease in anteroposterior translation of knees treated with this dynamic augmentation procedure is low. The procedure maintains translation close to the immediate post-operative level over a simulated rehabilitation period of 50’000 gait cycles and therefore supports anterior cruciate ligament repair during biological healing.

ADVANTAGES AND FEATURES OF ARTHROSCOPIC REINSERTION OF THE ANTERIOR CRUCIATE LIGAMENT OF THE KNEE JOINT WITH INTERNAL SPLINTING (internal brace technology)

“…Their results confirm ACL protection during its biological recovery. The resistance to load is 60-80N, cycle 50,000, is similar in an intact joint and after the internal bracing [1,8].…”

Implant preloading in extension reduces spring length change in dynamic intraligamentary stabilization: a biomechanical study on passive kinematics of the knee

“…The polyethylene braid as well as the specimens are, however, subjected to plastic deformation and wear under cyclic loading. It can be assumed that spring shortening will, therefore, decrease with time [8].…”

A Narrative Review of Four Different New Techniques in Primary Anterior Cruciate Ligament Repair: “Back to the Future” or Another Trend?

“…Häberli et al performed a biomechanical study to evaluate the course of translation during a simulated early postoperative phase after dynamic augmentation of anterior cruciate ligament tears [ 45 ]. The authors found a low increase in anteroposterior translation of the knees that were investigated and noted that this procedure supported ACL repair during biological healing.…”

“…Furthermore, Häberli et al in a biomechanical study of eight fresh-frozen human cadaveric knee joints showed that anteroposterior translation of knees treated with this dynamic augmentation procedure is low [ 45 ]. In another cadaveric study, it was shown that DIS with a preload of 80 N restores knee joint kinematics to a level comparable to that of an ACL-intact knee and is therefore capable of providing knee joint stability during ACL healing [ 35 ].…”