BackgroundChildren with cerebral palsy often have problems to support the body centre of mass, seen as increased ratio between excessive vertical ground reaction forces during weight acceptance and decreased below bodyweight in late stance. We aimed examine whether increasing ankle range motion through surgery restraining ankle-foot orthoses postoperatively would impact on force stance.MethodsG...

The amount of force developed by a muscle is related to many factors including where the muscle operates on its length-tension curve. It is well documented that placing the triceps surae muscle group in a lengthened state (i.e.: near maximal dorsiflexion) elicits maximum plantar flexion torque [1, 2]. Isolated gastrocnemius contracture (IGC) is characterized by limited dorsiflexion with the kne...

The responses of group III and IV triceps surae muscle afferents to intra-arterial injection of alpha,beta-methylene ATP (50 microg/kg) was examined in decerebrate cats. We found that this P2X(3) agonist stimulated only three of 18 group III afferents but 7 of 9 group IV afferents (P < 0.004). The three group III afferents stimulated by alpha,beta-methylene ATP conducted impulses below 4 m/s. P...

Background It is reported that 75% of long distance runners use a rearfoot strike (RFS) technique. This percentage decreases in faster runners, where the incidence of midfoot and forefoot strikers (FFS) increases [1]. It is possible that FFS better utilises the passive-elastic mechanisms of the lower limb reducing energy cost. Williams et al. [2] found runners who converted from RFS to FFS duri...

The Achilles tendon (AT) moment arm is an important determinant of ankle moment and power generation during locomotion. Load and depth-dependent variations in the AT moment arm are generally not considered, but may be relevant given the complex triceps surae architecture. We coupled motion analysis and ultrasound imaging to characterize AT moment arms during walking in 10 subjects. Muscle loadi...