Biomechanical evaluation of a modified dorsal double-plating fixation with adjustable joint and microthread designs for comminuted extra-articular distal radius fractures

Yu Hao Lin, Alvin Chao Yu Chen, Hsien Nan Kuo, Tsung Chih Yu, Ming Tsung Sun, Chun Li Lin*

*Corresponding author for this work

Research output: Contribution to journalJournal Article peer-review

4 Scopus citations

Abstract

This study evaluates the biomechanical strength of a modified dorsal double-plating (MDDP) internal fixation on artificial radius bones using the dynamic fatigue test. The plates are 1.6 mm thick and the upper L plate has an adjustable joint to allow the angular disposition of the bone plate to be changed to secure various bone fracture types. A dual-thread locking screw is used to enhance mechanical retention at the screw/bone interface. A finite element analysis is performed to examine the mechanical bone and fixation system response using a dual-microthread locking screw. An MDDP fixation is made with stainless steel by a manufacturer with ISO13485 quality management systems. Eighteen radius Sawbones were randomly placed into three groups and cut to a standard length of 2.5 cm from the articular surface to form 0 °, 30°, and 60° fracture configurations according to the A2 classification in the AO surgery reference. The adjustable joint in the L plates is adjusted and fixed using a fastener connection to have a 0°, 30°, or 60° configuration. Plates and screws are then positioned on the dorso-ulnar side for L plates and the dorso-radial side for I plates to create an angle of 90°. The specimens were subjected to oscillating loads of 10 to 150 N at 5 Hz for 20000 cycles. The average stiffness values after 20000 cycles were 425.7, 461.1, and 532.1 N/mm for the 0 °, 30°, and 60° constructs, respectively. No difference in stiffness was found for constructs with a given angle throughout the 20000 cycles of testing (p > 0.05). However, significant differences (p < 0.05) in stiffness were found between constructs with different angles at each 500-cycle interval. The lack of gross construct failure during cyclic testing and the reasonable stiffness prove that MDDP internal fixation is sufficiently stable to support restricted postoperative loads.

Original languageEnglish
Pages (from-to)29-34
Number of pages6
JournalJournal of Medical and Biological Engineering
Volume33
Issue number1
DOIs
StatePublished - 2013

Keywords

  • Biomechanics
  • Distal radius fracture
  • Dorsal double-plating
  • Fatigue test
  • Stiffness

Fingerprint

Dive into the research topics of 'Biomechanical evaluation of a modified dorsal double-plating fixation with adjustable joint and microthread designs for comminuted extra-articular distal radius fractures'. Together they form a unique fingerprint.

Cite this