Fig 1.
Drop tower and platform for impacting rabbit knee condyle.
A) impactor head with concave impact surface; B) load cell; C) accelerometer; D) platform; E) polyethylene block that supports the rabbit knee; F) height adjustable clamps; G) toggle clamps that fix the platform to drop tower.
Fig 2.
Posterior view of exposed medial condyle in rabbit cadaver secured by k-wire.
Solid yellow arrows indicate k-wire ends.
Fig 3.
Anatomical location of impact and anterior/posterior (AP) and proximal/distal (PD) axes:
a) A medial view of the condyle after impact. Red line shows AP and black line shows PD distances of the k-wire from the impact site. A ruler was also imaged for accurate length measurements. b) Schematic of the axes used for measurement of the AP and PD distances with the origin at the impact site.
Fig 4.
Multiple linear regression analysis indicated an association between measured and predicted impact parameters as a function of anterior-posterior (AP) and proximal-distal (PD) k-wire placement for a) peak stress, b) loading rate, c) impact duration and d) work.
The regression line is shown in solid red and the shaded area denotes the 95% confidence interval. The regression equation for each parameter is f(AP, PD) = a + b·AP + c·PD. The reported p and R2 values correspond to the overall regression model as assessed by ANOVA. * indicates Prob < |t| at the 0.05 level, indicating that the corresponding regression coefficient is significantly different from zero.
Table 1.
Impact parameters with consistent k-wire placement.
Fig 5.
Multiple linear regression analysis indicated correlation between measured and predicted failure parameters as a function of AP and PD k-wire placement for: a) failure load, b) failure loading rate and c) failure impulse.
Regression line is solid red and the shaded area indicates 95% confidence interval. The regression equation for each parameter is f(AP, PD) = a + b·AP + c·PD. The reported p and R2 values correspond to the overall regression model as assessed by ANOVA. * indicates Prob < |t| at the 0.05 level, indicating that the corresponding regression coefficient is significantly different from zero.
Table 2.
Failure parameters with consistent k-wire placement.