Assessment of healthy trapeziometacarpal cartilage properties using indentation testing and contrast-enhanced computed tomography

Abstract

Background: The trapeziometacarpal joint is a common site for osteoarthritis development in the hand. When osteoarthritis is present, it results in significant functional disabilities due to the broad range of activities performed by this joint. However, our understanding of osteoarthritis initiation and progression at this joint is limited because of the current lack of knowledge regarding the properties and structure of the corresponding cartilage layers. The objective of this study is to assess the morphological and mechanical properties of trapeziometacarpal cartilage via the combination of indentation testing and contrast-enhanced computed tomography. Such research may lead to the development of medical imaging-based approaches to measure cartilage properties in vivo. Methods: Intact first metacarpals and trapezia were extracted from 16 fresh-frozen human cadaver hands. For each specimen, load-displacement behavior was measured at 9 testing sites using a standardized indentation testing device to calculate the normal force and Young's modulus of the cartilage sub-regions. The specimens were then immersed in CA4+ contrast agent solution for 48 h and subsequently scanned with a resolution of 41 μm in a HR-pQCT scanner to measure cartilage thickness and attenuation. Finally, correlations between compressive Young's modulus and contrast-enhanced computed tomography attenuation of the cartilage were assessed. Findings: No significant difference was found in cartilage thickness between the trapezium and first metacarpal, but the comparison between articular regions showed thinner cartilage around the volar aspect of both the first metacarpal and the trapezium. The first metacarpal cartilage was stiffer than the trapezial cartilage. A significant positive correlation was observed between Young's modulus and mean contrast-enhanced CT attenuations in superficial and full-depth cartilage in both the first metacarpal and the trapezium cartilage. Interpretation: The quantitative measurements of trapeziometacarpal thickness and stiffness as well as a correlation between Young's modulus and contrast-enhanced computed tomography attenuation provides a method for the non-destructive in vivo assessment of cartilage properties, a greater understanding of thumb cartilage behavior, and a dataset for the development of more accurate computer models.

Cartilage wear patterns in severe osteoarthritis of the trapeziometacarpal joint: a quantitative analysis

“…In addition, there is consensus that cartilage degeneration of the first metacarpal originates and progresses from the volar area 4,10,30e32 . On the other hand, cartilage thinning in the trapezium is considered to volarly expand; however, this contradicts our findings 4,10,31 . These patterns were identified to have close relations to high load bearing in previous contact area studies 9,22,33e40 .…”

“…With aging, arthritis of the TMC joint progressively increases in prevalence, and a 91% prevalence has been reported in patients aged > 80 years 2 . Joint degeneration, concomitant with the progress of OA, results in the reduction of joint mobility, exacerbation of pain and swelling, weakness of grip and pinch, and overall disablement of the hand 3,4 . Reportedly, the pathophysiology of this disease is characterized by damage to the articular cartilage, osteophyte formation, changes in the subchondral bone, and synovitis 5 , and of these, the articular cartilage has garnered the most attention in relation to its pathogenesis, mainly because of its striking changes in advanced OA 6 .…”

“…The number of studies focusing on the spatial quantification of the articular cartilage of the TMC joint is limited because of the lack of accuracy in detecting the cartilage region on imaging analysis, as well as the morphological complexity of the thin cartilage. In particular, only few objective measures have been documented in advanced-stage OA 4,9,10 , although ascertaining the articular cartilage wear pattern in late-stage OA is essential for elucidating the etiology.…”

Biomechanics of the human thumb and the evolution of dexterity

“…Subsequently, the distance between the two central articular points was increased to 1.5 mm for all specimens ( Figure 1 A). This value, which represents the modern human average thickness of cartilage in the TMC joint (both bones taken together), 64 was used as a proxy of intra-articular space between the bones. It should be clarified that our models assumed uniform cartilage thickness at joints, despite the fact that previous research has shown that this varies across the articular surface.…”

dGEMRIC and CECT Comparison of Cationic and Anionic Contrast Agents in Cadaveric Human Metacarpal Cartilage

“…13 CECT studies demonstrate that cationic contrast agents accumulate throughout the bovine cartilage and are more sensitive to changes in the concentration of GAGs than anionic contrast agents. [14][15][16][17] Cationic agents are also successfully used to image ex vivo murine, 13,18 rabbit, 19 equine, 20,21 and human articular cartilage 22,23 as well as human menisci. 24 Additionally, CECT with CA4+ is used to image and characterize murine intervertebral disks.…”