ISO 22675:2016

Overview - ISO 22675:2016 (Prosthetics: ankle‑foot devices and foot units)

ISO 22675:2016 specifies requirements and test methods for assessing the strength, durability and service life of prosthetic ankle‑foot devices and foot units used in external lower‑limb prostheses. The standard focuses on realistic mechanical testing - chiefly a cyclic test that simulates the stance phase from heel strike to toe‑off, and static tests (proof and ultimate strength) that reproduce peak heel and forefoot loading.

Important: ISO 22675:2016 is intended for conformity assessment with the strength requirements of ISO 22523:2006 (clause 4.4). It is not a clinical selection guide for prescribing devices - misuse can pose safety risks for amputees.

Key technical topics and requirements

• Cyclic test procedure: standardized loading and locomotion profiles that combine vertical and anterior‑posterior ground reaction forces and tibia angle to simulate realistic walking loads for durability and service‑life verification.
• Static tests: static proof test and static ultimate strength test configured to generate heel and forefoot forces at lines of action corresponding to instants of maximum loading in the cyclic test.
• Coordinate system & test configurations: defined origin, axes, reference points, lines of action and effective ankle‑joint center for repeatable test setup.
• Test samples and preparation: requirements for sample selection (complete and partial structures), alignment, identification, and “worst‑case” alignment positions.
• Accuracy, equipment and end attachments: specification of test equipment, jigs, end‑attachment proof tests, and measurement accuracy for both static and cyclic rigs.
• Compliance, reporting and lab responsibilities: defined compliance conditions, number of tests, test submission documentation, laboratory log and detailed test report requirements.

Practical applications - who uses ISO 22675:2016

• Prosthetic manufacturers - to demonstrate device strength, durability and compliance with ISO 22523 strength requirements.
• Test laboratories and certification bodies - for standardized test methods, repeatable test setups and reporting.
• Regulators and conformity assessment authorities - to evaluate claims of strength and durability.
• Design and R&D teams - to validate new ankle‑foot designs under realistic loading profiles.

Note: Devices already tested to ISO 10328:2006 for the relevant strength requirements may not need retesting under ISO 22675:2016.

Related standards

• ISO 22523:2006 - strength requirements for prosthetic components (reference for conformity).
• ISO 10328:2006 - structural testing of lower‑limb prostheses (alternative test route referenced in the scope).

Keywords: ISO 22675:2016, prosthetics testing, ankle‑foot devices, foot units, cyclic test, static proof test, durability testing, prosthetic standards, ISO 22523, ISO 10328.