Calcaneofibular ligament may act as a tensioner of peroneal tendons as revealed by a contactless three-dimensional scan system on cadavers

Abstract

The ligaments are believed to have a role in stabilizing joints and regulating joint motion. Here, we propose a novel function of the calcaneofibular ligament (CFL), which stabilizes the ankle joint. In human bipedal locomotion, the peroneal muscles maintain mediolateral stability and prevent involuntary ankle inversion. To investigate the functional relationship between the peroneal longus tendon (PLT), brevis tendon (PBT), and CFL, we quantitatively analyzed the positional changes of the tendons by using a contactless three-dimensional optical scan system. Eighteen cadaveric specimens were included in the study. Interestingly, with increased tension of the CFL, the tendons significantly moved toward the lateral direction (P < 0.001), compared with their position when the CFL was detached. The actual lift amount reached 2.0 ± 0.8 mm for the PLT and 1.9 ± 1.0 mm for the PBT. These results strongly suggest that a tensed CFL can lift the peroneal tendons and may act as a “tensioner” for the effective transmission of muscle contraction. This phenomenon contributes to postural control, especially in regaining balance on uneven terrain, and provides a new perspective for the exercise methods or understanding the ankle joint instability due to sprains.

The calcaneofibular ligament courses toward the groove at the inferior fibula and the CFL groove becomes a landmark for ultrasonography

“…The CFL coursed toward the CFL groove with curving in the deep layer of the peroneal muscle tendon and sheath, and when the CFL tenses according to the talocrural and subtalar joint motion, the bend and loosen state became straight and tense. In a biomechanical study using a 3D scan system, when the ankle is impelled into an inversion position, the tensed CFL lifts the peroneal muscle tendons laterally [41]. The CFL curved from the effect of the peroneal tendons.…”

Effect of foot position during plantarflexion on the neural drive to thegastrocnemiiin runners with Achilles tendinopathy

“…Greater instability can stimulate inhibitory proprioceptive feedback from muscle spindles and Golgi tendon organs, which may impact motor unit behaviour in various ways 32,33 , including reducing motor unit discharge rate. In addition, it is possible that this increased joint stretch created by the testing position feet in, may increase the contribution of passive joint structures (stretch-sensitive afferent receptors in ligaments) in conjunction with the ankle muscles to increase joint stiffness and provide better support and joint stability [33][34][35] . These afferent receptors from the ankle ligaments may assist with the adjustment of the activity of other ankle stabilizers during plantarflexion such as the soleus and the fibularis longus 36,37 .…”