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Observational Study
. 2025 Apr 9;49(4):368-377.
doi: 10.1097/PXR.0000000000000449.

Evaluation of activity and function before and immediately after the provision of a microprocessor knee in individuals with transfemoral amputation

Silvia Caggiari  1 , Tim Randell  2 , Chantel Ostler  3   4 , Alex Dickinson  4   5 , Peter Worsley  1   4
Affiliations
Observational Study

Evaluation of activity and function before and immediately after the provision of a microprocessor knee in individuals with transfemoral amputation

Silvia Caggiari et al. Prosthet Orthot Int. .

Abstract

Background: In many cases, individuals with lower limb amputation become less active because of impaired balance and stability and increased risk of falling. Microprocessor knees (MPKs) have been shown to reduce the risk of falls, improve balance, and increase function, evaluated with self-reported scales and questionnaires. This study aims at investigating whether the patient-reported improvements are reflected in objective physical activity (PA) parameters estimated from actimetry sensors and assess the short-term provision of an MPK.

Study design: Transfemoral amputee patients (n=29) undertaking an MPK trial at 2 prosthetic centers in the South of England were recruited for this study. Self-reported and functional test outcomes (Activities Balance Confidence, Reintegration of Normal Living Index, Prosthesis Evaluation Questionnaire scores, and 2-min walk test) were obtained before and after (4 weeks) the provision of the MPK. Activity levels were recorded over 7 consecutive days pre- and post-MPK.

Results: Self-reported scores and function test outcomes showed a general improvement in most of the patients after the provision of the MPK, with a statistically significant change ( p < 0.05) in Activities Balance Confidence, Reintegration of Normal Living Index, Prosthesis Evaluation Questionnaire scores, and 2-min walk test. By contrast, the activity-based parameters estimated from actimetry showed no statistically significant changes ( p > 0.05). Associations between self-reported and functional outcomes and actimetry parameters were limited.

Conclusions: Perceived and in-clinic outcome measures improved after short-term provision of an MPK for transfemoral amputees. However, PA did not change in this cohort of patients over the study period. More longitudinal studies are needed to characterize the impact of MPK provision on PA and societal participation.

Keywords: activity monitor; function; lower limb amputation; microprocessor knees; mobility; physical activity.

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Conflict of interest statement

The author(s) disclosed no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
Mean values of (top left) ABC, (top right) RNLI, (bottom left) PEQ, and (bottom right) 2MWT, collected with the nMPK (blue) and after the provision of the MPK (orange). Error bars indicate the standard deviation, and * indicates a statistically significant difference (p < 0.05). 2MWT, 2-min walk test; ABC, Activities Balance Confidence; PEQ, Prosthesis Evaluation Questionnaire; MPK, microprocessor knee; nMPK, non-MPK; RNLI, Reintegration of Normal Living Index.
Figure 2.
Figure 2.
Pin wheel view of data estimated from the actimetry for P#1.
Figure 3.
Figure 3.
Mean values of number of steps (top left), upright time (top middle), sedentary time (top right), active time (bottom left), and number of sit to stand events (bottom middle), collected with the nMPK (blue) and after the provision of the MPK (orange). Error bars indicate the standard deviation. MPK, microprocessor knee; nMPK, non-MPK.
See this image and copyright information in PMC

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References

    1. Saunders TJ, McIsaac T, Douillette K, et al. Sedentary behaviour and health in adults: an overview of systematic reviews. Appl Physiol Nutr Metab 2020;45(suppl 2):S197–s217. - PubMed
    1. Public Health England. Health Matters: Getting Every Adult Active Every Day; 2016. Available at: https://www.gov.uk/government/publications/health-matters-getting-every-.... Accessed January 03, 2019.
    1. Public Health England. Physical Activity: Applying All Our Health; 2018. Available at: https://www.gov.uk/government/publications/physical-activity-applying-al.... Accessed January 13, 2019.
    1. Bull FC, Al-Ansari SS, Biddle S, et al. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. Br J Sports Med 2020;54:1451–1462. - PMC - PubMed
    1. Guthold R, Stevens GA, Riley LM, Bull FC. Worldwide trends in insufficient physical activity from 2001 to 2016: a pooled analysis of 358 population-based surveys with 1·9 million participants. Lancet Global Health 2018;6:e1077–e1086. - PubMed

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