Schneiderman BA, Yang S, Dipane M, et al. - This research was sought to correlate total knee arthroplasty (TKA) periprosthetic tissues in lymphocyte transformation testing (LTT) positive v. negative patients, and patients with conventional CoCrNi v. hypoallergenic implants. Researchers examined periprosthetic tissues from 26 revision cases of well-fixed, aseptic, but painful/stiff TKAs. The outcomes of this study revealed that periprosthetic TKA tissue reactions were indistinguishable between LTT positive and negative patients. The periprosthetic tissue response was not prognosticated by LTT. It has been reported that ALVAL scores of hypoallergenic revision implant tissue trended higher than primary CoCrNi implant tissue. The data considered that a positive LTT may not indicate that a periprosthetic immune reaction is the cause of pain and stiffness post-TKA.