RT Journal Article ID 7acba3df08241ce8 A1 Perkins, Meredith A1 Lowell, Julie A1 Arnholt, Christina A1 MacDonald, Daniel A1 Kerkhof, Anita L. A1 Kurtz, Steven M. A1 Mihalko, William M. T1 Is Soft Tissue Laxity Associated with Tissue Metal Concentrations after Total Knee Arthroplasty? JF Journal of Long-Term Effects of Medical Implants JO JLT YR 2018 FD 2018-05-10 VO 28 IS 2 SP 79 OP 85 K1 total joint replacements K1 excessive wear K1 soft tissue balancing AB Increased joint laxity is associated with excessive polyethylene wear, but the correlation between laxity and metal wear has not been established. Fifteen necropsy-retrieved primary total knee replacements were mounted into a custom knee-testing machine that measured anterior–posterior, varus–valgus, and internal–external rotational laxity at 0°, 30°, 60°, and 90° of flexion. Inductively coupled plasma-mass spectrometry analysis was performed to measure the cobalt (Co), chromium (Cr), and titanium (Ti) concentrations in periprosthetic tissue samples. Spearman's rank correlations were performed to determine whether a significant correlation (p < 0.05) existed between soft tissue laxity and tissue metal concentrations. At 0° flexion, decreased posterior displacement was negatively correlated with elevated Co and Cr concentrations. At 30° flexion, decreased external rotation and varus deflection was negatively correlated with elevated Ti concentrations. At 60° flexion, decreased anterior displacement was negatively correlated with elevated Cr concentrations and decreased varus deflection was negatively correlated with increased Ti concentrations. At 90° flexion, decreased anterior displacement was negatively correlated with elevated Co and Cr concentrations. To our knowledge, this is the first study to investigate the correlation between tissue metal concentration and laxity. Decreased laxity was associated with elevated metal concentrations in periprosthetic tissue. PB Begell House LK https://www.dl.begellhouse.com/journals/1bef42082d7a0fdf,639e402206fa0df3,7acba3df08241ce8.html