ISO 7206-13 is an ISO test method used in orthopedic implant verification to measure the torque required to loosen the fixation between a femoral head and the neck/stem (cone) on stemmed femoral components for partial or total hip joint prostheses.
Because head-to-cone junction designs vary (tapers and other fixation approaches), setup details and acceptance expectations are typically tied to the exact device design and the edition cited. If you need help aligning your fixture concept, transducer range, and data capture with your specific implant configuration, talk with our team.
ISO 7206-13:2016 — Implants for surgery — Partial and total hip joint prostheses — Part 13: Determination of resistance to torque of head fixation of stemmed femoral components
ISO 7206-13 focuses on a single mechanical integrity question for hip implants: how resistant the assembled head fixation is to loosening when torque is applied under defined laboratory conditions.
The method is intended for femoral components where the head and the cone (neck/stem) are separate components secured together (commonly via a conical taper or another fixation method), including metallic and non-metallic material combinations.
Quick Definition
What it is: A laboratory method to determine the torque required to loosen the fixation of a hip prosthesis head relative to the neck/stem (cone) when the head is not intended to rotate in service.
What it supports: Design verification, process validation, and comparative evaluation of head-to-cone fixation robustness for stemmed femoral components.
What This Standard Covers
ISO 7206-13 describes how to apply torque to an assembled head-and-cone junction and determine the torque needed to loosen that fixation under specified lab conditions.
It is specific to stemmed femoral components used in partial or total hip joint replacements where the head is a separate part attached to the cone (neck/stem).
The standard does not prescribe how to examine test specimens after testing; that is typically agreed between the lab and the party submitting the specimen.
Why This Standard Matters in Testing
The head-to-cone interface is a critical mechanical junction in many hip systems. Torque-to-loosen testing provides a direct, quantitative check on how strongly the assembled head fixation resists rotational loosening.
This type of result is commonly used to support documented verification evidence, compare assembly approaches, and check consistency when manufacturing or assembly variables (surface condition, seating method, contamination control, or assembly tooling) are under review.
Common Materials, Product Types, or Applications Covered
Common products: Stemmed femoral components for total hip arthroplasty (THA) and partial hip replacements where a separate femoral head is secured to a cone/neck/stem.
Common junction types: Locking conical tapers and other head fixation approaches where the head is intended to remain rotationally fixed relative to the cone.
Common material combinations: Metallic and non-metallic components, including mixed-material head/cone assemblies, where applicable to the implant system.
Common Test or Verification Workflow
Most ISO 7206-13 programs are run as part of a broader implant verification plan, with the torque-to-loosen test positioned as an assembly/junction integrity evaluation rather than a full fatigue or wear program.
Typical workflow steps:
- Define the specific head and cone components to be evaluated (including sizes, materials, and surface/finish variants).
- Assemble the head onto the cone using the specified or controlled assembly approach for the study (tooling and method selection can materially affect outcomes).
- Secure the specimen in a fixture that constrains the cone while allowing controlled torque application to the head.
- Apply torque per the method and record the torque value associated with loosening of the head fixation.
- Document specimen identification, assembly conditions, and the measured torque-to-loosen results in the test report.
Equipment Commonly Used for This Standard
ISO 7206-13 is equipment-driven: accurate torque application and measurement require a rigid mechanical setup, controlled alignment, and traceable instrumentation.
Common equipment families: Torque test systems or servohydraulic/electromechanical test frames fitted with a torque application mechanism; calibrated torque transducers; rigid specimen fixturing to clamp the cone/neck/stem and drive the head; and data acquisition/software to capture torque and test events.
Selection cautions: The required torque range, allowable compliance, fixture geometry, and how “loosening” is defined/observed depend on the implant junction design and the edition cited. If you are scoping a new setup or need to size transducer capacity and fixture stiffness for your device, you can request pricing for a torque test configuration matched to your lab workflow.
How to Read This Designation or Revision
Base standard: ISO 7206-13:2016 refers to Part 13 of the ISO 7206 series, published in 2016.
Amendments: ISO also publishes amendments that apply to the base document. ISO 7206-13 has an amendment published as ISO 7206-13:2016/Amd 1:2022, which may affect how the method is applied or referenced in documentation.
Practical tip: When a customer or regulator cites ISO 7206-13, confirm whether the citation expects the base edition alone or the base edition plus applicable amendments.
Related Standards, Methods, or Frameworks
ISO 7206-13 is one part of the ISO 7206 series for partial and total hip joint prostheses. Many verification programs pair multiple ISO 7206 parts to cover different mechanical or dimensional questions across the implant system.
When planning a test matrix, keep ISO 7206-13 narrowly scoped to head fixation torque resistance, and use other references as needed for complementary requirements (for example, other mechanical tests in the ISO 7206 family or device-specific verification plans).
Talk to a testing specialist about ISO 7206-13 setups
If you need a torque-to-loosen setup for head fixation testing—fixture concepting, transducer sizing, and a practical data capture package—share your implant geometry and target torque range and we can help you configure the right system. Start by contacting our team.