Abstract
The mechanical characteristics of the patellar tendon are primarily derived from cadaver studies, which may not necessarily be applicable to the human patellar tendon, in vivo; however, recent developments in high-resolution magnetic resonance imaging (MRI) techniques have opened up new perspectives for structural characteristics of the tendon and ligament by non-invasive methods. The purpose of this study is to use MRI to quantity the elongation and the strain of the human patellar tendon in vivo during full extension to 60° of knee flexion. The apparent elongation in the lateral-central (lc) portion of the patellar tendon was slightly less than in the central (c) and medial-central (mc) portions with knee flexion. The apparent mean-central strains (mnc = (c + mc + lc) / 3) of the patellar tendons, which corresponded to strains in the central one-third portions of patellar tendons, were (average and standard deviation) 0.091 ± 0.034 and 0.135 ± 0.007 at 30° and 60° of the knee flexion, respectively.
