Simultaneous Strain Measurement With Determination of a Zero Strain Reference for the Medial and Lateral Ligaments of the Ankle

Abstract

The strain changes of the central part of the anterior talofibular ligament (ATFL), the posterior talofibular ligament (PTFL), the calcaneofibular ligament (CFL), and the tibiocalcaneal ligament (TCL) were measured simultaneously for a full range of ankle motion. Twelve fresh frozen amputated ankles were used. To measure the strain changes of the ligaments, a Galium-Indium-filled silastic strain transducer was implanted in the center of each ligament. The zero strain reference was determined immediately after the measurement of strain changes in five of the 12 ankles by tensile testing of each bone-ligament-bone preparation. The maximum strain change of the ATFL, the PTFL, the CFL and the TFL were 7.9%, 5.9%, 5.3% and 5.2%, respectively. The ATFL was elongated in plantar flexion and shortened in dorsiflexion. The PTFL and the CFL were shortened in plantar flexion and elongated in dorsiflexion. The TCL was the longest around the neutral position and became shorter in planter flexion and dorsiflexion. The results showed that the ATFL was taut in plantar flexion over 16.2 degrees, the PTFL and the CFL were taut in dorsiflexion over 18 degrees and 17.8 degrees respectively, and the TCL was taut between 9.5 degrees of dorsiflexion and 9.5 degrees of plantar flexion. The length change pattern was different among the ankle ligaments, although there was only a slight difference between that of the PTFL and the CFL. This study provides fundamental data useful in studying ankle ligament reconstruction.

Determination of dynamic ankle ligament strains from a computational model driven by motion analysis based kinematic data

“…A cadaver study by Ozeki et al (2002) shows that maximum strains in the ATaFL, PTaFL, CaFL, and ATiFL for a physiological range of ankle motion are 7.9%, 5.9%, 5.3%, and 5.2%, respectively. Similarly Colville et al (1990), using cadavers with 201 of dorsiflexion, document ankle ligament strains of approximately 4%, 6% and 8% in the ATaFL, ATiFL and PTiFL, respectively, which have been recently simulated by Wei et al (2011) using the current computational model.…”

“…Approximately 80% of ankle sprains are lateral ankle sprains caused by excessive inversion (Fong et al, 2009) while high ankle sprains comprise about 10% (Boytim et al, 1991). Some studies have examined ankle ligament strains using cadavers (Colville et al, 1990;Ozeki et al, 2002;Tochigi et al, 2005). Using a combined dual-orthogonal fluoroscopic and magnetic resonance imaging (MRI) technique, De Asla et al (2009) measure in vivo changes in length of the anterior talofibular ligament (ATaFL) and calcaneofibular ligament (CaFL) in four static foot positions.…”

A robot-driven computational model for estimating passive ankle torque with subject-specific adaptation

“…Data based on the published literature [14,16,[30][31][32] and passive torque collected from participants were used for model validation. The lengths of ankle ligaments depend on not only the bone geometry, but also their origin and insertion points on bones.…”

“…Ankle assessment at the level of muscles and ligaments usually consists of cadaver-based sectioning studies [13,14], invasive techniques [15] and image-based methods [16]. Cadaver-based and invasive methods are not suitable for rehabilitation.…”

Orthopaedic sport biomechanics – a new paradigm

“…In-vivo strain of ligament is often measured by differential variable reluctance transducer (DVRT), liquid mercury strain gauge, and Hall-effect strain transducers (Woo et al, 1999). Studies of in-vivo strain of ankle ligaments with cadaver ankles revealed that ATFL is elongated in plantarflexion and shortened in dorsiflesion, but the reverse is found in calcaneofibular ligament (CFL) and posterior talofibular ligament (PTFL) (Ozeki et al, 2002). Butler and Walsh (2004) added that every ligament at lateral ankle does relax when the loaded is less than 5N, however, the ATFL does not relax to same extent as the other ligaments.…”