Effects of elevated vacuum on in-socket residual limb fluid volume: Case study results using bioimpedance analysis

Abstract

Abstract-Bioimpedance analysis was used to measure the residual limb fluid volume of seven transtibial amputee subjects using elevated vacuum sockets and nonelevated vacuum sockets. Fluid volume changes were assessed during sessions with the subjects sitting, standing, and walking. In general, fluid volume losses during 3 or 5 min walks and losses over the course of the 30 min test session were less for elevated vacuum than for suction. Numerous variables, including the time of day that data were collected, soft tissue consistency, socket-tolimb size and shape differences, and subject health, may have affected the results and had an equivalent or greater effect on limb fluid volume compared with elevated vacuum. Researchers should well consider these variables in the study design of future investigations on the effects of elevated vacuum on residual limb volume.

Systematic review of effects of current transtibial prosthetic socket designs—Part 2: Quantitative outcomes

“…They pointed out that two factors had been neglected in the studies: (1) the effect of VAS sockets on participants with comorbidities and/or other causes of amputation than trauma and (2) the employment of in-socket, real-time residual limb volume measurement technique to further assess the effect of VAS sockets on volume control. These two factors were later considered in a case series study with somewhat promising results in favor of the VAS socket [47].…”

“…The most frequent design was a crossover design (n = 9) [27][28][30][31][32][33][41][42][43], followed by five single-subject/case studies [34][35][38][39]44], four randomized crossover trials [13][14]21,29], and three case series [26,[46][47]. The remaining studies were repeated-measure design (n = 1) [45], randomized controlled trials (n = 2) [22,24], cross-sectional design (n = 2) [36][37], and prospective study (n = 1) [40] Table 1.…”

“…Five studies reported the effects of VAS and TSB sockets on residual limb volume, from which one study was classified as having robust evidence [13], one as having moderate evidence [21], and three as having weak evidence [35,42,47].…”

“…In a case series, Sanders et al (DBS 13) examined the effect of a VAS socket on in-socket volume changes using bioimpedance [47]. They compared the results obtained with a TSB (non-VAS) socket and a TSB socket with pin lock system.…”

Elevated vacuum suspension preserves residual-limb skin health in people with lower-limb amputation: Randomized clinical trial

“…Both terms differentiate the suspension method from passive suction or valve systems. EVS sockets continue to grow in popularity on the basis of improved fit and function [5][6][7][8] through a reduction of pistoning [5,[9][10][11] and residual-limb volume management [5,[12][13]. A recent systematic review of EVS studies [14] identified only two peer-reviewed journal publication related to the effects of EVS on residual-limb physiology [5,15] and underscores the need for more evidence-based research in this underserved field.…”