Can high-functioning amputees with state-of-the-art prosthetics walk normally? A kinematic and dynamic study of 40 individuals

Background Previous work has highlighted the highly functional post-rehabilitation level of military individuals who sustained traumatic amputation. Understanding how these individuals walk with their prosthesis could be key to setting a precedent for what is realistically possible in the rehabilitation of individuals with amputations. Objective The aim of this paper is to answer how “normal” should the gait of an individual with an amputation(s) be and can we aspire to mimic able-bodied gait with the most advanced prosthetics in highly functioning individuals? Methods This was a cross-sectional study comparing the gait of severely injured and highly functional UK trans-tibial (n = 10), trans-femoral (n = 10) and bilateral trans-femoral (n = 10) military amputees after completion of their rehabilitation programme to that of able-bodied controls (n = 10). Joint kinematics and kinetics of the pelvis, hip, knee and ankle were measured with 3-D gait analysis during 5 min of walking on level ground at a self-selected speed. Peak angle, moment or range of motion of intact and prosthetic limbs were compared to control values. Results Joint kinematics of unilateral trans-tibial amputees was similar to that of controls. Individuals with a trans-femoral amputation walked with a more anterior tilted pelvis (P = 0.006), with reduced range of pelvic obliquity (P = 0.0023) and ankle plantarflexion (P < 0.001) than controls. Across all amputee groups, hip joint moments and power were greater and knee and ankle joint moments were less than for controls. Conclusions This is the first study to provide a comprehensive description of gait patterns of unilateral trans-tibial, trans-femoral and bilateral trans-femoral amputees as compared with healthy able-bodied individuals. The groups differed in joint kinematics and kinetics, but these can be expected in part because of limitations in prosthesis and socket designs. The results from this study could be considered benchmark data for healthcare professionals to compare gait patterns of other individuals with amputation who experienced similar injuries and rehabilitation services

Cerebral lateralisation during signed and spoken language production in children born deaf

The effect of sensory experience on hemispheric specialisation for language production is not well understood. Children born deaf, including those who have cochlear implants, have drastically different perceptual experiences of language than their hearing peers. Using functional transcranial Doppler sonography (fTCD), we measured lateralisation during language production in a heterogeneous group of 19 deaf children and in 19 hearing children, matched on language ability. In children born deaf, we observed significant left lateralisation during language production (British Sign Language, spoken English, or a combination of languages). There was no difference in the strength of lateralisation between deaf and hearing groups. Comparable proportions of children were categorised as left-, right-, or not significantly-lateralised in each group. Moreover, an exploratory subgroup analysis showed no significant difference in lateralisation between deaf children with cochlear implants and those without. These data suggest that the processes underpinning language production remain robustly left lateralised regardless of sensory language experience

Neurobiology of auditory statistical information processing.

While statistical information is crucial for language acquisition and online speech processing, experimental work has just begun identifying the neural mechanisms mediating these processes as well as their functional importance. We review these in the current chapter. Several core areas identified in this experimental work are regions of the supratemporal plane and lateral temporal cortex that appear to be sensitive to the degree of statistical regularity in an input and potentially initial word segmentation, and left inferior frontal regions that play a role in word recognition, but may not be involved in the coding of statistics per se. The basal ganglia appears to have a role in online temporal predictions and anticipation, with a particularly important role for the putamen, a core part of the cortico-basal motor loop. Finally, while there is some evidence for functional and structural connectivity between frontal, temporal and basal ganglia regions, future work is needed to examine the relation between statistical processing mechanisms and the strength of functional and structural connectivity within this network