Damage in a Distal Radius Fracture Model Treated With Locked Volar Plating After Simulated Postoperative Loading.
J Hand Surg Am
; 43(7): 679.e1-679.e6, 2018 07.
Article
em En
| MEDLINE
| ID: mdl-29426604
ABSTRACT
PURPOSE:
"Damage" is an engineering term defining a period between a state of material perfection and the onset of crack initiation. Clinically, it is a loss of fixation due to microstructural breakdown, indirectly measured as a reduction of stiffness of the bone-implant construct, normalized by the cross-sectional area and length of the bone. The purpose of this study was to characterize damage in a cadaver model of extra-articular distal radius fracture with dorsal comminution treated using 2-column volar distal radius plates.METHODS:
Ten matched distal radii were randomly divided into 2 groups group I specimens were treated with a volar distal radius plate with an independent, 2-tiered scaffold design; group II specimens (contralateral limbs) were treated with a volar plate with a single-head design for enhanced ulnar buttressing. Specimens were cyclically loaded to simulate a 6-month postoperative load-bearing period. We report damage after a defined protocol of cyclical loading and load to failure simulating a fall on an outstretched hand.RESULTS:
Group II specimens experienced more damage under cyclic loading conditions than group I specimens. Group I specimens were stiffer than group II specimens under load-to-failure conditions. Ultimate force at failure in group I and group II specimens was not different. Specimens failed by plate bending (group I, n = 6/10; group II, n = 2/10) and fracture of the lunate facet (group I, n = 4/10; group II, n = 8/10).CONCLUSIONS:
Group I specimens had less screw cutout at the lunate facet than group II specimens under cyclic loading as indicated by lower damage measures and fewer facet fractures during load-to-failure testing. The overall strength of the construct is not affected by plate design. CLINICAL RELEVANCE Microstructural damage or a loss of fixation due to an overly rigid volar plate design may cause malunion or nonunion of fracture fragments and lead to bone-implant instability.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fraturas do Rádio
/
Placas Ósseas
/
Teste de Materiais
/
Suporte de Carga
/
Fixação Interna de Fraturas
Tipo de estudo:
Evaluation_studies
/
Guideline
Limite:
Humans
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article