2021 ISAKOS Biennial Congress Paper
Lateral Elbow Laxity Is Affected By The Integrity Of The Radial Lateral Collateral Complex. A Cadaveric Model With Sequential Releases And Varus Load Simulating Everyday Activities.
Davide Cucchi, MD, Bonn, Deutschland GERMANY
Francesco Luceri, MD, Milano, Italy/Lombardia ITALY
Alessandra Menon, MD, Milano, Milano ITALY
Carlo Eugenio Zaolino, MD, Milan ITALY
Andrea Zagarella, MD, Milano GERMANY
Michele Catapano, MD, Milano GERMANY
Mattia Radici, MD, Milan ITALY
Nicola Migliaccio, MD, Milan ITALY
Dario Polli, Prof., Milano ITALY
Pietro Simone Randelli, MD, Prof., Milan ITALY
Paolo Arrigoni, Milan ITALY
ICLO Teaching Centre, Verona, ITALY
FDA Status Not Applicable
Summary
The radial lateral collateral complex is confirmed as an important static lateral stabilizer, supporting a pathological model based on its insufficiency and culminating with a symptomatic minor instability of the lateral elbow.
Abstract
Background
An elongation of the radial lateral collateral complex (R-LCL) can provoke a symptomatic minor instability of the lateral elbow (SMILE) leading to lateral elbow pain. Biomechanical models investigated the effects of elongation, partial or complete lesions of the R-LCL on lateral elbow stability are lacking. To evaluate how partial and complete R-LCL release affect the radiocapitellar joint stability in a setting of controlled varus load and progressive soft tissue release.
Methods
Ten fresh-frozen specimens were obtained and mounted on a custom-made support to control elbow flexion/extension and allow controlled varus loading. Stress tests were performed on all intact specimens under gravity load alone, 0.5 kg load applied to the hand and 1 kg load applied to the hand. After load application, anteroposterior radiographs were obtained. The following release sequence was applied to all specimens: release of the anterior half of the common extensor origin; pie crusting of the R-LCL; R-LCL release. After each release, stress tests and radiographs were performed. The varus joint angulation of the elbow (a), was measured by two examiners as main outcome parameter.
Results
Significant changes in a from the initial condition occurred after each release and a significant effect of varus load on a was documented for all release steps. A significant effect of the releases on a could be documented for all identical varus load conditions. A linear regression model
to describe the effect of varus load on a was generated.
Conclusions
Varus loads simulating everyday activities produce changes in a already in the intact specimen, which are linearly dependant on the applied moment and persist also after releasing the lateral stabilizing structures. With progressive load, a pie crusting of the R-LCL is the minimal procedure able to provoke a significant change in a and a complete R-LCL release produces additional increase in a in all testing conditions.