摘要 |
<p>The strength of a healing bone fracture is measured by rotating the bones about their axis at each side of the fracture relative to each other and measuring the needed rotational moment as a function of the rotational angle obtained. An apparatus is used comprising a first (5) and a second (8) ring-shaped member, studs (15) connecting these members (5, 8) with an axial distance from each other, and fixing pins (6, 14) rigidly connecting the respective ring-shaped members and the bone (1) at respective sides of the fracture. One ring member (8) comprises a first (10) and a second (9) element joined so that they can be rotated but not axially displaced relative to each other, the first element (10) carrying the studs (15) and the second element (9) carrying the fixing pins (14). The elements (9, 10) forming the second ring member (8) are engaged by respective jaws of a tong-shaped tool provided with measuring devices (42, 47) to measure the length of the movement of the jaws and the force needed for this movement.</p> |