A comparison of gastrocnemius muscle–tendon unit length during gait using anatomic, cadaveric and MRI models

Comparison of the efficacy of three isolated gastrocnemius recession procedures in a cadaveric model of gastrocnemius tightness

“…Moreover, the gastrocnemius spans three joints, so when the subtalar joint was held in the neutral position, the length of the gastrocnemius influenced the angle of the knee and ankle during ambulation [19]. According to the MRI-based model, the gastrocnemius muscle-tendon unit may be divided into three parts by the joint centres of the knee and ankle [20]. Our modeling method only comparatively shortens the middle part of the gastrocnemius between the two joint centres by increasing the length of the tibia, without disturbing the moment arm at the knee and the ankle.…”

Medial gastrocnemius muscle behavior during human running and walking

“…Average sarcomere lengths, which were estimated by dividing the fascicle length by the average number of sarcomeres in series in fascicles [22], have been estimated during human locomotion and superimposed on a force-length relationship for human muscle derived from the data of Walker and Schrodt (see Refs. [17] and [20] for details). The shaded areas refer to the estimation which is based on the present results.…”

“…Ref. [20]) between the models for the MTU length calculation, which can influence the estimation of TT length. In our understanding, these differences deal mainly with the calculation of the moment arms.…”

Experimental study on the role of the ankle push off in the walk-to-run transition by means of a powered ankle-foot-exoskeleton

“…Although the endogenous gastrocnemius muscle-tendon length depends both on the knee and ankle angle [26] it is likely that the experimental conditions mostly affected the ankle because of the uni-articular insertion of the pneumatic muscles. As such the lower ankle angle at toe off constitutes a more favourable configuration for the plantarflexors [27].…”