Contact Area and Static Pressure Profile at the Plate‐Bone Interface in the Nonluted and Luted Bone Plate

Abstract

Contact area and pressure between 6-hole broad dynamic compression plates and 20 pairs of equine third metatarsal bones were measured using nonluted and luted plating techniques. Pressure-sensitive film (pressure ranges 10 to 50 MPa and 50 to 130 MPa) was used as the static pressure transducer. Nonluted and one of two luting techniques were tested on each pair of bones; each luting technique was tested on 20 bones. Quantitative determinations of contact area and pressure were made using computerized image processing techniques. Mean (+/- SD) total contact area for nonluted plates was 18.49% +/- 3.5% of the potential plate-bone contact area. Luting increased (P < .05) total contact area to 25.56% +/- 4.0% and 31.29% +/- 6.6% for the respective luting techniques. The effects of luting on contact area were dependent on the contact pressure. At contact pressure ranges 10 to 20 and 21 to 35 MPa, luting increased contact area. In contact pressure ranges 36 to 45 and 50 to 65 MPa, plate-bone contact was inherently greatest and plate luting had no significant effect on contact area. In contact pressure ranges 66 to 99 and 100 to 126 MPa, luting decreased contact area. Contact area was increased at lower contact pressures at the expense of higher pressure contact. Contact in the middle third of the plate was 20% to 40% of the contact at either end of the plate. Plate luting increased contact area best where plate-bone contour was most similar.

Increasing strut porosity in silicate‐substituted calcium‐phosphate bone graft substitutes enhances osteogenesis

“…The ovine model has been used successfully in other studies to assess the osteogenic capacity of calcium phosphate‐based implants 5, 32. The rationale for selecting this model was based on the similarity between bone metabolism in sheep and that in humans33 and the fact that sheep support their body weight post surgery on treated limbs,34, 35 and the size of the animal permits the creation of a practically‐sized defect 15. We made metaphyseal defects in the medial femoral condyle as this site bears more weight and so would be expected to encourage mechanical stimulation around the implant, thus encouraging bone ingrowth and remodeling.…”

Effects of the bone-plate material and the presence of a gap between the fractured bone and plate on the predicted stresses at the fractured bone

“…Such direct contact causes bone necrosis under the rigid plates as a long-term effect. In order to eliminate the damage to the bone's periosteal blood supply, low contact surface bone-plates, locking compression plates and limited contact dynamic compression plates have been used for fractured bone fixation [10][11][12][13][14][15][16][17][18]. The insertion of soft biodegradable material between the rigid plates and bone has also been used to prevent damage to the bone's periosteal blood supply [19].…”

Bio-inspired method based on bone architecture to optimize the structure of mechanical workspieces

“…Indeed, the trabecular architecture and the cortical bone makes possible to achieve a strong compromise between stiffness, weight, fatigue resistance, impact resistance. The local strain at the trabeculae connections enables to ensure a better distribution of the contact pressure [12], [13]. This structure meets a variety of specifications and have been adapted to the lifestyle of each living species [14], [15], [16].…”