A new ISO standard will help ensure that spinal disc prostheses meet requirements for wear resistance, particularly important as once implanted these will need to absorb the impact from the body’s daily activities for years to come.
The primary users of this ISO standard will be medical device manufacturers and laboratories in public and private sectors, providing biomechanical testing services for medical devices. The estimated worldwide market size for artificial disc prostheses will exceed USD 1 billion by the year 2010.
Intervertebral spinal discs act as cushions that absorb shocks to a person’s back resulting from their daily activities. These discs can be damaged through age or following an accident and put pressure on spinal nerves, which can be very painful. Most people will experience back ache due to damaged intervertebral discs at some stage in their lifetime. Unfortunately, the most common methods to deal with neck and back pain fail in a significant number of patients.
Implant surgery of spinal disc prostheses provides an innovative alternative with a tremendous potential that could help patients with conditions such as spondylosis – a degenerative disorder that can result in a loss of normal spinal structure and function. However, the development of prosthetic discs presents a number of challenges. The device must allow movement, provide stability, and be resistant to impact from a person’s daily activities. It should not be destructive and exhibit great endurance.
ISO 18192 will promote the development of safe and resistant prostheses for patients and constitute a useful tool for the medical industry. The first part of what is intended as a multi-part standard outlines a test procedure for the relative angular movement between articulating components and specifies the pattern of the applied force, speed and duration of testing, sample configuration and test environment.
ISO 18192-1 will allow the uniform testing and comparison of this relatively new technology ensuring the performance of different prosthesis. Its consensus based methodology will provide a reliable and concise reference. Within the medical industry, this standard will provide transparency, improve communication and level the playing field for competing suppliers. Surgeons will be able to rely on soundly based comparative information for different devices.
Dr. Christian Kaddick, project leader for the development of the standard commented “The value of this standard to the medical community is that it provides direction on how to evaluate the wear performance of a new class of medical devices. Without standardized methods, it is impossible to compare data between laboratories. ISO 18192-1 thus removes a potential barrier, speeding and facilitating technological developments in this area.”
The standard was developed by ISO subcommittee SC 5, Osteosynthesis and spinal devices of technical committee ISO/TC 150, Implants for surgery. ISO/TC 150/SC 5 is currently working on the envisaged second part of the standard: ISO 18192-2, Implants for surgery – Wear of total intervertebral spinal disc prostheses, Part 2: Nucleus replacements.
ISO 18192-1, Implants for surgery – wear of total intervertebral spinal disc prostheses, Part 1: Loading and displacement parameters for wear testing and corresponding environmental conditions for test costs 108 Swiss francs and is available from ISO national member institutes (see the complete list with contact details) and from ISO Central Secretariat through the ISO Store or by contacting the Marketing & Communication department (see right-hand column).
