A new screw and technique for the treatment of ruptured multiaxial joint ligaments: a preliminary study on the scapholunate dissociation of the wrist

A wide range of techniques on ligament reconstruction have been proposed, summarized in three main categories: The direct suturing or indirect reconstruction of the ligament using adjuvant devices, the “biological ligament ” substitution with the use of autografts or allograft and the “artificial ligament substitution”, with polyester fibers. We propose a new orthopedic screw, the Flexy Screw (FS) and the FS technique for repairing unstable joints due to ligament damage. The tools used for the FS insertion and removal, is all included in the overall flexyscrew system (FSS).In this work we have particularly developed the FS technique for the scapholunate ligament rupture (SLR). The value 18.03N/mm (SD9.6) for the linear elastic mean stiffness for the SLIL, and 14.4N/mm for the FS, furthermore the FS max load 138N at 10mm, in comparison with the average elastic limit of 47N at 3mm for the SLIL are considered satisfactory. Furthermore, the FS technique is aiming to be applied in a wide spectrum of unstable joints needing “ligament substitution”, because, as a mechanical orthopedic device can be adapted in order to simulate more closely the physiological mechanical properties of the ligaments.