Economic benefits of microprocessor controlled prosthetic knees: a modeling study

Abstract

BackgroundAdvanced prosthetic knees allow for more dynamic movements and improved quality of life, but payers have recently started questioning their value. To answer this question, the differential clinical outcomes and cost of microprocessor-controlled knees (MPK) compared to non-microprocessor controlled knees (NMPK) were assessed.MethodsWe conducted a literature review of the clinical and economic impacts of prosthetic knees, convened technical expert panel meetings, and implemented a simulation model over a 10-year time period for unilateral transfemoral Medicare amputees with a Medicare Functional Classification Level of 3 and 4 using estimates from the published literature and expert input. The results are summarized as an incremental cost effectiveness ratio (ICER) from a societal perspective, i.e., the incremental cost of MPK compared to NMPK for each quality-adjusted life-year gained. All costs were adjusted to 2016 U.S. dollars and discounted using a 3% rate to the present time.ResultsThe results demonstrated that compared to NMPK over a 10-year time period: for every 100 persons, MPK results in 82 fewer major injurious falls, 62 fewer minor injurious falls, 16 fewer incidences of osteoarthritis, and 11 lives saved; on a per person per year basis, MPK reduces direct healthcare cost by $3676 and indirect cost by $909, but increases device acquisition and repair cost by $6287 and total cost by $1702; on a per person basis, MPK is associated with an incremental total cost of $10,604 and increases the number of life years by 0.11 and quality adjusted life years by 0.91. MPK has an ICER ratio of $11,606 per quality adjusted life year, and the economic benefits of MPK are robust in various sensitivity analyses.ConclusionsAdvanced prosthetics for transfemoral amputees, specifically MPKs, are associated with improved clinical benefits compared to non-MPKs. The economic benefits of MPKs are similar to or even greater than those of other medical technologies currently reimbursed by U.S. payers.Electronic supplementary materialThe online version of this article (10.1186/s12984-018-0405-8) contains supplementary material, which is available to authorized users.

Cost-effectiveness and budget impact of the microprocessor-controlled knee C-Leg in transfemoral amputees with and without diabetes mellitus

“…Prosthesis subject-specific publications in prosthetic and orthotic journals where identified manually. In addition, results of a literature review of a recently published health economic study [20] were considered. Input parameters are summarized in Table 1.…”

“…According to Wong et al [39], 26.8% of all falls had medical consequences. Chen et al [20] calculated a lower proportion of medical falls (10.4%) based on three studies [40][41][42] in the elderly general US population. We tested this value in the sensitivity analysis.…”

“…Therefore, it is important to investigate whether the price of the C-Leg is justified by the additional benefits. Four studies [16][17][18]20] have assessed the cost-effectiveness of the C-Leg compared to NMPKs. Three studies were from Europe [16][17][18] and one study from the US [20].…”

“…Four studies [16][17][18]20] have assessed the cost-effectiveness of the C-Leg compared to NMPKs. Three studies were from Europe [16][17][18] and one study from the US [20]. Results varied from the C-Leg-dominating NMPKs in a patient cohort with an average age of 45-46 years old (societal perspective) [18] to an ICER of close to 90,000 Euros per quality-adjusted life year (QALY) gained in a cohort of amputees aged 40+ years old at the time of first prosthesis (payer's perspective) [17].…”

“…Results varied from the C-Leg-dominating NMPKs in a patient cohort with an average age of 45-46 years old (societal perspective) [18] to an ICER of close to 90,000 Euros per quality-adjusted life year (QALY) gained in a cohort of amputees aged 40+ years old at the time of first prosthesis (payer's perspective) [17]. Only one study included the medical and economic consequences of falling, which had a major impact on the cost-effectiveness of the C-Leg [20].…”