Skin Temperature Prediction in Lower Limb Prostheses

Abstract

Increased temperature and perspiration within a prosthetic socket is a common complaint of many amputees. The heat dissipation in prosthetic sockets is greatly influenced by the thermal conductive properties of the socket and interface liner materials. These materials influence the body's temperature regulation mechanism and might be the reason for thermal discomfort in prosthetic sockets. Monitoring interface temperature at skin level is notoriously complicated. The problem might be considered notorious because embedding wires and sensors in an elastomer eventually results in elastomer failures because of the high strain induced when donning a liner (amputees roll the liners onto their limbs). Another reason is because placing sensors and wires directly against the skin could cause irritation and chaffing over just a short period of time. We describe a route wherein if the thermal properties of the socket and liner materials are known, the in-socket residual limb temperature could be accurately predicted by monitoring the temperature between socket and liner rather than skin and liner using the Gaussian process technique.

Residual limb skin temperature and thermal comfort in people with amputation during activity in a cold environment

“…Many sensors broke during the protocol (44% ; Table 1) because we chose a thin-gauge wire to minimize the risk of residual limb abrasion during an hour of moderate activity. A potential solution would be to validate an algorithm based on the correlation between liner-socket interface temperatures and skin-mounted thermistors [8] at a range of freezing ambient temperatures. Choosing to minimize risk at the expense of a more complete data set and the challenges associated with recruiting a narrow population of participants with lowerlimb amputation (i.e., subjects who participated in snow sports) limited our ability to compare limb temperatures by thermistor location.…”

“…A prior study examined residual limb skin temperatures (n = 9) during a 30 min walking session in a moderate ambient room temperature (~20°C) and reported a 3°C increase in skin temperature followed by little cooling (<1°C) after prolonged rest (60 min) [2]. Mathur et al also reported a residual limb skin temperature increase (2°C) during a 10 min walk at 0.6 m/s in a 20°C chamber (n = 1), but temperatures remained constant when the chamber temperature was 10°C [8]. However, the effect of cold ambient temperatures (0°C), as are frequently experienced during winter months, on residual limb skin temperatures remains unknown.…”

The effect of liner design and materials selection on prosthesis interface heat dissipation

“…2 In lower limb prosthesis wearers, even light exercise causes an increase in temperature of the skin-prosthesis interface [3][4][5][6][7] that dissipates away slowly. 3,5,7 Prosthesis impermeability means sweat cannot evaporate, and when this hot and sweaty interface is subjected to ambulation forces, skin damage can rapidly occur. 6,[8][9][10][11] Components that aim to minimize or delay heat and sweat discomfort are emerging, 12,13 but more studies are required to comprehensively determine their efficacy.…”

Wearable mobile sensor and communication platform for the in-situ monitoring of lower limb health in amputees

“…The temperature profile of the residual limb and the liner were analysed for different ambient temperatures and it was noted that in all the cases the trace of the liner temperature was very closely correlated with that of the residual limb temperature. This enabled us to implement the Gaussian processes modelling technique to predict the residual limb temperature by monitoring the liner interface temperature with an accuracy of 95% [9], thereby providing a non-invasive measurement practice. The sensor data can be accessed from a central database which is username and password protected.…”