Subchondral bone density in the human elbow assessed by computed tomography osteoabsorptiometry: A reflection of the loading history of the joint surfaces

Abstract

The functional adaptation of bone tissue to the mechanical stresses acting on it has been convincingly established. This association should apply as well to the subchondral bone, reflecting the long-term distribution of stress over the joint surfaces. Thirty-six specimens of the human elbow joint were investigated by computed tomography osteoabsorptiometry in order to assess the distribution of the subchondral mineralization. The distal surfaces usually were more highly mineralized than the proximal components of the joint, whereas the humeroulnar and the humeroradial parts exhibited a similar degree of mineralization. The fovea of the radial head always showed a central density maximum, and the trochlear notch usually presented a bicentric distribution pattern, with maxima beneath the ventral and dorsal regions of the articular surface. The different patterns of subchondral mineralization were shown to reflect the loading history of the overlying articular surfaces, which is determined mainly by geometrical factors. The flatter socket of the humeroradial joint leads to central load transmission, but the deeper socket of the humeroulnar joint will, by contrast, give rise to bicentric stress distribution.

Morphomechanics of the humero‐ulnar joint: II. Concave incongruity determines the distribution of load and subchondral mineralization

“…Bicentric ventro-dorsal distribution patterns of sub- chondral mineralization lend, however, convincing support t o the assumption that concave incongruity plays an important role in humero-ulnar load transmission during physiological day-to-day use (Tillmann, 1971(Tillmann, , 1978Eckstein et al, 1994bEckstein et al, , 1995. Pauwels (1963Pauwels ( ,1980, in his pioneering study, described the distribution of subchondral bone density in the trochlear notch as a "materialized diagram of stress" (verkorpertes Spannungsdiagramm).…”

Computer simulation of subchondral bone adaptation to mechanical loading in an incongruous joint

“…With higher loads, however, the maximal strain energy density is encountered in the center, and the joint socket therefore yields a central density maximum. In fact, in some individuals, a monocentric density distribution can be observed in the trochlear notch (Pauwels, 1963), and this pattern may be associated with a continuous articular surface (Tillmann, 1971(Tillmann, , 1978Eckstein et al, 1994aEckstein et al, , 1995d. The continuous articular surface appears to be present throughout adolescence (Oberlä nder et al, 1984) but is a rare finding in the elderly (Tillmann, 1971(Tillmann, , 1978Oberlä nder et al, 1984).…”

A densitometric analysis of the human first metatarsal bone

“…The deformation followed by relaxation results in both pressure and tension changes within the bone which stimulate bone formation and remodeling (Scott, 1957 ;Carter et al 1991) which include changes in bone density. Thus the morphology of a bone is related to its mechanical loading history and, thus, density (Scott, 1957 ;Thompson, 1961 ;Burr, 1980 ;Hvid et al 1985 ;Vogel et al 1988 ;Martin, 1991 ;Melton et al 1993 ;Zysset et al 1994 ;Eckstein et al 1995).…”