Background Suture tape is a recent development to augment a Brostrom repair at least during the healing phase of the native tissues used for stabilization of the lateral ankle ligaments. The purpose of this study was to evaluate whether suture tape is an effective mechanical stabilizer against anterior talar drawer in a cadaver experiment when tested with a validated arthrometer. Methods Different stability conditions were created in 14 cadaveric foot and leg specimens. Following anterior talofibular ligament (ATFL) dissection, isolated suture tape ATFL reconstruction was compared to the unaltered specimens, to the condition with ATFL cut, to the ATFL plus calcaneofibular ligament (CFL) cut conditions, and to the ATFL, CFL, and posterior talofibular ligament transected specimens. Three-dimensional bone-to-bone movement between fibula and calcaneus were simultaneously recorded using bone pin markers. Anterior translation was analysed between 20 and 40 N anterior talar drawer load, applied by an ankle arthrometer. Test conditions were compared using non-parametric statistics. Results Dissection of ATFL increased anterior talar drawer in arthrometer and bone pin marker analyses ( p = 0.003 and 0.004, respectively). When the CFL was additionally cut, no further increase of the anterior instability could statistically be documented ( p = 0.810 and 0.626, respectively). Following suture tape reconstruction of the ATFL, stability was not different from the unaltered ankle ( p = 0.173). Conclusions Suture tape augmentation of the ATFL effectively protects the unstable anterolateral ankle in the sagittal plane. The CFL does not seem to stabilize against the anterior talar drawer load.

A new instrumented device was developed to quantify ankle joint stability during an anterior talar drawer test. The aim of the present study was to validate this device comparing bone kinematics with arthrometer measurement outcomes. An anterior talar drawer test was performed with 14 cadaver legs using a custom instrumented ankle arthrometer. Using clusters of bone-pin markers, the relative three-dimensional movement of calcaneus, talus, and fibula was simultaneously measured. Anterior drawer test was applied on the intact foot and after sequentially sectioning the anterior talofibular ligament, the calcaneofibular ligament, and the posterior talofibular ligament. Cutting the anterior talofibular ligament caused a significant increase in bone-pin measured anterior translations of calcaneus and talus as well as in the anterior translation of the arthrometer. Analysis of receiver operating characteristic curves indicates a fair to good ability to discriminate between the intact and the sectioned conditions with the arthrometer. Distal distraction, inversion, and internal rotation movements were observed when two and three ligaments were cut. Results revealed that the ankle arthrometer was sensitive to detect changes in bone-to-bone movements during an anterior talar drawer test, when the anterior talofibular ligament was sectioned. Presumably due to movements in additional planes of motion, the arthrometer was not able to differentiate between situations with one or more ligaments cut. In conclusion, the instrumented anterior talar drawer tester may augment current procedures in assessing ankle instability primarily caused by ruptures of the anterior talofibular ligament.