Ligament force and joint motion in the intact ankle: a cadaveric study

Abstract

The aims of this study were to measure the forces in the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) and the motion in the tibiotalar and subtalar joints during simulated weight-bearing in eight cadaver ankle specimens. An MTS test machine was used to apply compressive loads to specimens held in a specially designed testing apparatus in which the ankle position (dorsiflexion-plantarflexion and supination-pronation) could be varied in a controlled manner. The forces in the ATFL and CFL were measured with buckle transducers. Tibiotalar motion and total ankle joint motion were measured with an instrumented spatial linkage. The specimens were positioned sequentially at 10 degrees dorsiflexion, neutral, and 10 degrees and 20 degrees plantarflexion, and this sequence was repeated at 15 degrees supination, neutral pronation/supination, and 15 degrees pronation. Force and motion measurements were recorded in each of these positions with and without a 375 N compressive load simulating weight-bearing. From 10 degrees dorsiflexion to 20 degrees plantarflexion, all motion occurred in the tibiotalar joint. In contrast, the ratio of subtalar motion to tibiotalar motion was 3:1 for supination-pronation and 4:1 for internal-external rotation. Inverse loading patterns were observed for the ATFL and CFL from plantarflexion to dorsiflexion. Compressive loading did not affect CFL tension, but it magnified the pattern of increasing ATFL tension with plantarflexion. The largest increase in ATFL force was observed in supination and plantarflexion with a compressive load (76 +/- 23 N), whereas CFL tension mainly increased in supination and dorsiflexion with a compressive load (109 +/- 28 N). In conclusion, the results showed that the ATFL acted as a primary restraint in inversion, where injuries typically occur (combined plantarflexion, supination and internal rotation). Also, the subtalar joint was of primary importance for normal supination-pronation and internal-external rotation.

Kinematics and kinetics of an accidental lateral ankle sprain

“…The primary ligamentous restraint to an inversion moment in a plantarflexed position is the anterior talofibular ligament (Bahr et al, 1998). In line with this, inversion sprains have traditionally been described as resulting from a combination of inversion and plantar flexion (Andersen et al, 2004).…”

Differences in Lateral Ankle Laxity Measured via Stress Ultrasonography in Individuals With Chronic Ankle Instability, Ankle Sprain Copers, and Healthy Individuals

“…Bahr et al 3 indicated that variability in ligament orientation could be a source of variability in the results of talocrural joint displacement testing in cadaver ankles; however, Taser et al 34 found that the anatomical orientation of the ATFL between the origin and insertion is not widely variable, despite variability in ATFL lengths among studies. These factors, along with differences in injury history, may account for the wide variability observed within each group on these laxity measures.…”

A Composite Athletic Tape With Hyperelastic Material Properties Improves and Maintains Ankle Support During Exercise

“…Within the functional range of motion, the ligament provides little resistance to motion; however, as the ankle approaches the end of its range of motion, the ligament reaches high strains and greatly increases its resistance to further motion, providing passive ankle support. 4,8,25,26,31 The second disadvantage of conventional athletic tape as compared to natural ligament is that the former looses much of its support characteristics within a relative short time after the initiation of exercise. In the present study, conducted on 11 athletes, we found that conventional athletic tape reduced ankle flexibility in inversion by an average of 33% initially but by only 15% following a 30-minute exercise session, a 55% loss of support.…”