Biomechanical analysis of the Universal 2 implant in total wrist arthroplasty: a finite element study

Abstract

Little is known about the mechanics of in vivo loading on total wrist prostheses where many studies have looked at the mechanics of other types of arthroplasty such as for the hip and the knee which has contributed to the overall success of these types of procedures. Currently surgeons would prefer to carry out arthrodesis on the wrist rather than consider arthroplasty as clinical data have shown that the outcome of total wrist arthroplasty is poorer than compared to the hip and knee. More research is needed on the loading mechanisms of the implants in order to enhance the design of future generation implants. This study looks at the load transfer characteristics of the Universal 2 implant using a finite element model of a virtually implanted prosthesis during gripping. The results showed that the loading on the implant is higher on the dorsal and ulnar aspect than on the volar and radial aspect of the implant. The whole load is transmitted through the radius and none through the ulna.

Early Cup Loosening After Metal-on-Metal Total Joint Replacement of the Trapeziometacarpal Joint: A Retrieval Study

“…This may partly be due to the volume of implant surgery in the hand (being lower than in the aforementioned joints), and partly due to the complicated anatomy of the wrist and carpus. FEA studies have been published for wrist implants (Bajuri et al, 2013;Gislason et al, 2017) and for silicone implants in the metacarpophalangeal (MCP) joints (Podnos et al, 2006). In the CMC1 joint, two FEA studies have studied joint replacements, not including paper one in this thesis.…”

Mechanical performance comparison of two surgical constructs for wrist four-corner arthrodesis via dorsal and radial approaches

“…For this purpose, a threedimensional FE model of the wrist after FCA virtual surgery was developed, seeking to assess and compare stresses of radial and dorsal surgical constructs during two common tasks in the elderly. The mechanical behaviour of wrist surgical constructs remains poorly understood, with only a few studies focused on total wrist arthroplasty (Bajuri et al, 2013;Gislason et al, 2017;Grosland et al, 2004). As far as the authors know, this is the first FE model of an arthrodesis wrist representing the implant with all major wrist structures and driven by realistic load sets.…”

“…Regarding the loads applied to the model, intrinsic muscles act as dynamic stabilisers of the wrist. However, they were not included in the numerical model as in other FE studies for reasons of simplification (Gislason et al, 2017). Instead, we limited wrist movement by constraining the metacarpal bones to move in their primary axis and by modelling no relative movement in the carpometacarpal joints.…”

The biomechanical importance of the scaphoid-centrale fusion during simulated knuckle-walking and its implications for human locomotor evolution

“…These values were obtained from humans and applied to all the models because there is no available information of these values for the other analysed apes. Moreover, the use of homogeneous material properties for the bone is also widely accepted in the community, especially when www.nature.com/scientificreports www.nature.com/scientificreports/ modelling carpal bones since there is no accurate published information available for all the analysed species 35 . We simplified the models by defining constant thickness for the cartilage and the bone.…”