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This study aimed at evaluating spatiotemporal parameters (STP) and symmetry index (SI), commonly used for evaluating amputee gait for routine clinical use, in individuals with unilateral transtibial amputations wearing energy storage and return (ESAR) feet with fixed ankles, prosthetic feet with adaptive ankles (PFAA) and prosthetic feet with microcontrolled adaptive ankles (PFAA-MC) in ramp ascent and descent. Thirteen individuals with transtibial amputations walked up and down a ramp. The STPs were measured in the amputated and intact legs and the relationship between them was quantified using the SI. The results showed that the use of PFAA-MC decreases walking speed in ramp descent (P < 0.018). However, this was the only parameter that showed a significant change. Hence, the differences in the amputees’ gait pattern when using the above-mentioned prostheses may not be reflected by STP and their SI.

Background Minimum Toe Clearance (MTC) is defined as the minimum vertical distance between the lowest point under the front part of the foot and the ground, during mid-swing. Low values of MTC and walking on inclines are both related to higher probability of tripping and falling in lower limb amputees. New prosthetic designs aim at improving MTC, especially on ramps, however the real effect on MTC still needs investigation. The objective of this study was then to evaluate the effect of different prosthetic designs on MTC in inclined walking. Methods Thirteen transtibial amputees walked on a ramp using three different prostheses: non articulating ankle (NAA), articulating hydraulic ankle (AHA), and articulating hydraulic ankle with microprocessor (AHA-MP). Median MTC, coefficient of variation (CV), and tripping probability (TP) for obstacles of 10 and 15 mm were compared across ankle type in ascent and descent. Findings When using AHA-MP, larger MTC median values for ascending (P ≤ 0.001, W = 0.58) and descending the ramp (P = 0.003, W = 0.47) were found in the prosthetic limb. Also significantly lower CV was found on the prosthetic limb for both types of AHA feet when compared to NAA for descending the ramp (P = 0.014, W = 0.45). AHA-MP showed the lowest TP for the prosthetic leg in three conditions evaluated. On the sound limb results showed the median MTC was significantly larger (P = 0.009, W = 0.43) and CV significantly lower (P = 0.005, W = 0.41) when using an AHA in ascent. Interpretation Both AHA prosthetic designs help reduce the risk of tripping of the prosthetic limb by increasing the median MTC, lowering its variability and reducing TP for both legs when ascending and descending the ramp. For most of the conditions, AHA-MP showed the lowest TP values. Findings suggest that AHA prostheses, especially AHA-MP could reduce the risk of tripping on ramps in amputees.

Musculoskeletal modelling could be a potential tool in diagnosis and treatment design. In particular, in children with cerebral palsy, it is thought that gait modelling and simulation could contribute to improve clinical decisions. Nevertheless, the models used to simulate crouch gait are not as accurate as necessary to bring the results into the clinic. In this study, two models proposed in the literature are compared. The results showed differences in joints moments and in the static optimization process possibly caused by differences in estimations of anthropometric segment inertial values and the use of different cost functions, respectively. However, both models provided good agreement with the recorded EMG data.

This study measured spatio temporal parameters (STP) and their symmetry index (SI) in order to evaluate the differential effect on the gait pattern of individuals with unilateral transtibial amputations when using two different prostheses. Twelve individuals with transtibial amputations walked on level ground using an Energy Storage and Return (ESAR) prosthesis with fixed ankle and a prosthetic foot with adaptive ankle (PFAA). The STP were measured in the prosthetic and sound limbs and the symmetry index for each parameter was calculated afterwards. The results showed no statistically significant differences between the prostheses for the STP measured, and this was the case both for the prosthetic and sound limbs. Similarly, the SI did not reflect statistically significant differences when the different prostheses were used. Thus, the results suggest that the STP studied and their SI may not reflect differences when evaluating ESAR versus PFAA prostheses in the conditions proposed in this study.