A Finite-Element Analysis of Kienböck’s Disease

Abstract

A finite-element analysis model of the lunate was established using geometrical data obtained from cadaveric bones. The lunate cortex was modelled with triangular and quadrilateral elements and its intraosseous structure was represented either as a homogenous elastic structure or as an anisotropic network of cortical bone beams (trabeculae) with different orientations and thicknesses. Compressive loads applied to the metacarpus were distributed in the carpus against the fixed radius and ulna. The ulnar variance had a strong influence on the ratios radiolunate/ulnolunate total load and peak pressures. The distribution of internal stresses was markedly affected by the lunate uncovering index. The evolution of a simulated incomplete fracture was dramatically influenced by morphological parameters: with positive ulnar variance, the fracture did not progress, but in the presence of three associated conditions, negative ulnar variance, a high lunate uncovering index and angulated trabeculae, the fracture progressed and the proximal part of the lunate collapsed. This study supports the concept that some lunates are predisposed to Kienböck's disease because their anatomy induces abnormal internal stresses, which allow an incomplete fracture to progress, under heavy loading conditions, and cause progressive collapse and localised trabecular osteonecrosis.

A first step in finite-element simulation of a grasping task

“…Simulation of several scaphoid bone fracture were performed, which could explain the clinical evolution of the behavior of the wrist. He also developed a more realistic threedimensional FE model of lunate bone to investigate the specific Kienbock's disease [14]. Carrigan et al [15] developed a FE model to study the load transmission into the carpus under static load and concluded to the importance of the cartilage and the rotational degree of freedom of the carpal in the pressure distribution into the wrist.…”

The Effect of Proximal Lunate Morphology “Zapico Classification” on Kienböck’s Disease

“…Ledoux et al (11) proposed that ulnar minus, lunate uncovering, and angulated trabecular cause the micro fractures not to heal properly. Garcia-Elias and Vidal (13), in a group of KD 28 men and 12 women, connected the lunate length to lunate morphology but assumed some exceptions, unlike the Schuurman et al (14) with 68 wrists with no connection of ulnar length to lunate shape.…”

“…Some authors have suggested that the morphology and microstructure of the wrist bones, intraosseous pressure, and mechanical stresses have etiologic and prognostic values (3)(4)(5). Ulnar variance (UV) is a good example of many author's attempt to show that the negative UV is playing a key role (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15), despite many normal individuals with a negative UV, that doesn't get KD (6) and many KD patients with positive UV (16). One of the theories that has repeatedly been proposed is the effect of lunate morphology in KD, either as an etiologic or a prognostic factor like Viegas and Zapico (15,17,18).…”

Establishment of canine models of lunatomalacia through liquid nitrogen freezing

“…Lunatomalacia, one of the main causes of wrist pain, is a disease characterized by cystic change, fragmentation and progressive collapse of the lunate (1–3). Lunatomalacia was first reported by Peste in 1843.…”