Prosthetic Prescription Assessment and Candidacy

Prosthetic prescription assessment and candidacy is the reasoning that determines whether a person who has lost a limb is an appropriate candidate for a prosthesis, what functional level they are likely to achieve, and which components and design the prescription should specify. It is the front end of prosthetic care, where clinical, functional and personal factors are weighed before a device is built.

Definition

Prosthetic prescription assessment and candidacy is the clinical evaluation of a person's suitability for a prosthesis and of the functional level they can be expected to attain, which together inform the specification of an appropriate device.

Scope

The entry covers candidacy evaluation, the use of functional-classification systems (such as the Medicare Functional Classification Level, or K-level, scheme), performance-based and self-report mobility outcome measures used to support prescription, and the link between predicted function and component selection. It is a methodological and reference topic, not individualised advice on whether a given person should be fitted.

Key concepts

• Candidacy evaluation
• Functional classification (K-level)
• Medicare Functional Classification Level system
• Amputee Mobility Predictor
• Self-report mobility measures
• Component selection by functional level
• Predicted versus achieved mobility

Mechanisms

Assessment combines history, physical examination, and standardised measures to estimate a person's potential mobility, which is then expressed through a functional-classification level that guides component choice. Performance-based tools such as the Amputee Mobility Predictor and self-report instruments such as mobility questionnaires quantify function and have been used to support level assignment; studies have examined how well such measures predict assigned levels. Because the assigned level constrains which components are prescribed and reimbursed, the validity and consistency of this classification step directly shapes the device a person receives.

Clinical relevance

Candidacy and functional-level judgements underpin who receives a prosthesis and what kind, and they frame how prosthetic outcomes are studied. This entry describes the structure and evidence of that decision process for reference and education; it does not provide criteria for deciding an individual person's candidacy, which requires direct clinical assessment.

Evidence & guidelines

The evidence base includes validation studies of functional-classification systems and mobility outcome measures, and surveys of how practitioners use them. Practitioner surveys have raised questions about the validity of functional-level classification, and several studies have examined whether performance-based measures can support or predict level assignment; much of this work is observational and single-centre.

Debates

Is functional-level classification valid and reliable enough to drive prescription?

A practitioner survey found substantial concern about the validity of the Medicare Functional Classification Level system and support for using objective outcome measures to aid level assignment, while other studies test whether measures such as the Amputee Mobility Predictor can predict the assigned level.

Seminal works

• borrenpohl-2016
• dillon-2018
• davies-2003

Frequently asked questions

What is a functional classification level (K-level)?

It is a category that describes a person's current or expected functional ability with a prosthesis, ranging from limited household ambulation to high-impact activity. It is widely used to justify and select prosthetic components, though its validity has been debated.

How are mobility outcome measures used in candidacy assessment?

Performance-based tools such as the Amputee Mobility Predictor and self-report questionnaires quantify a person's mobility, and they have been studied as ways to support or predict functional-level assignment that guides the prescription.