How Common Are Spinal Injuries?
According to the National Spinal Cord Injury Statistical Center (NSCISC), there are around 17,700 spinal cord injuries each year. This is roughly 54 injuries per one million people in the United States. Of those people, around 31% are hospitalized again after the injury. 288,000 people are thought to be living with a spinal cord injury. In some cases, implants are needed to deal with these injuries.
Testing materials is crucial, especially when it involves such a sensitive part of the body. ASTM F1717-21 provides test methods for spinal implant constructs in a vertebrectomy model.
What Is a Spinal Implant Assembly?
According to ASTM F1717-21, a spinal implant assembly is a complete spinal implant configuration intended for surgical use. It contains interconnections, anchors, and longitudinal elements. It may also contain transverse elements.
What Are the Standard Test Methods for Spinal Implant Constructs?
The scope of ASTM F1717-21 is rather large. It provides information on the materials and methods for static and fatigue testing. This testing is done on spinal implant assemblies in a vertebrectomy model. Depending on the proposed spinal location and proposed method of application to the spine, the tested materials for most combinations of spinal implant components can be specific.
The tests covered in ASTM F1717-21 are aimed to give a foundation for mechanical comparison in spinal implant assemblies for the past, present, and future. The test methods “allow comparison of spinal implant constructs with different intended spinal locations and methods of application to the spine.” However, the test methods do not delineate the levels of performance.
The test methods in ASTM F1717-21 provide guidelines for load types as well as approaches of applying loads. For the comparative evaluation of spinal implant assemblies, there are three defined static load types and one fatigue test. These test methods establish guidelines for the measuring of displacements, the determination of the yield load, and the evaluation of strength and stiffness of the spinal implant assembly.
ASTM F1717-21: Standard Test Methods for Spinal Implant Constructs in a Vertebrectomy Model is available on the ANSI Webstore.