A new concept for expansion screws on the cervical spine using shape memory alloy - a feasibility study.
Journal
Journal of neurological surgery. Part A, Central European neurosurgery
ISSN: 2193-6323
Titre abrégé: J Neurol Surg A Cent Eur Neurosurg
Pays: Germany
ID NLM: 101580767
Informations de publication
Date de publication:
08 Nov 2023
08 Nov 2023
Historique:
medline:
9
11
2023
pubmed:
9
11
2023
entrez:
8
11
2023
Statut:
aheadofprint
Résumé
In general, sufficient anchoring of screws in the bone material ensures the intended primary stability. Shape memory materials offers the option of using temperature-associated deformation energy in a targeted manner in order to do justice to the special situation of osteoporotic bones or the potential lack of anchoring. An expansion screw was developed that takes this possibility and these requirements into account. Using finite element analysis, the variability of screw configuration and actuator was assessed from shape memory. In particular, the dimensioning of the screw slot, the actuator length and the actuator diameter as well as the angle of attack in relation to the intended force development were considered. As a result of the finite element analysis, a special configuration of expansion screw and shape memory element could be found. Accordingly, with an optimal screw diameter of 4 mm, an actuator diameter of 0.8 mm, a screw slot of 7.8 mm in length and an angle of attack of 25 degrees, the best compromise between individual components and high efficiency in favor of maximum strength can be predicted. Shape memory material offers the possibility of using completely new forms of power development. By skillfully modifying the mechanical and shape memory elements, their interaction results in a calculated development of force in favor of a high primary stability of the screw material used. Activation by means of body temperature is a very elegant way of initializing the intended locking and screw strength.
Sections du résumé
BACKGROUND
BACKGROUND
In general, sufficient anchoring of screws in the bone material ensures the intended primary stability.
METHODS
METHODS
Shape memory materials offers the option of using temperature-associated deformation energy in a targeted manner in order to do justice to the special situation of osteoporotic bones or the potential lack of anchoring. An expansion screw was developed that takes this possibility and these requirements into account. Using finite element analysis, the variability of screw configuration and actuator was assessed from shape memory. In particular, the dimensioning of the screw slot, the actuator length and the actuator diameter as well as the angle of attack in relation to the intended force development were considered.
RESULTS
RESULTS
As a result of the finite element analysis, a special configuration of expansion screw and shape memory element could be found. Accordingly, with an optimal screw diameter of 4 mm, an actuator diameter of 0.8 mm, a screw slot of 7.8 mm in length and an angle of attack of 25 degrees, the best compromise between individual components and high efficiency in favor of maximum strength can be predicted.
CONCLUSION
CONCLUSIONS
Shape memory material offers the possibility of using completely new forms of power development. By skillfully modifying the mechanical and shape memory elements, their interaction results in a calculated development of force in favor of a high primary stability of the screw material used. Activation by means of body temperature is a very elegant way of initializing the intended locking and screw strength.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Subventions
Organisme : Bundesministerium für Bildung und Forschung
ID : 03ZZ1026C
Informations de copyright
Thieme. All rights reserved.
Déclaration de conflit d'intérêts
The authors declare that they have no conflict of interest.