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The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anteriol tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force–moment sensor testing system, valgus torques ranging from 0.0 to 10.0 N m were applied in nine increments on the intact and ACL‐deficient knee in flexion ranging from 0° to 90°. At 15° of knee flexion, the coupled ATT and ITR were significantly increased in the ACL‐deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p < 0.05), while coupled ITR increased a maximum of 85% (5.1°, p < 0.05). At 30°, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 N m and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p < 0.05) and a maximum increase in coupled ITR of 38% (3.6°, p < 0.05). At 45°, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p < 0.05), but only at torques ⩾ 6.7 N m. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 N m was applied. Low valgus torque elicited tibial subluxation in the ACL‐deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL‐deficient and ACL‐reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.

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Background Randomized trials have demonstrated the efficacy of several new therapies for heart failure (HF) with reduced ejection fraction over the preceding two decades. This study investigates whether these therapeutic advances have translated into improvement in outcomes for patients with advanced HF referred to a heart transplant center. Methods and Results Patients with HF (n=2507) referred to a single university center were analyzed in three 6-year eras during which medical and device therapies were evolving: 1993-1998 (era 1), 1999-2004 (era 2), and 2005-2010 (era 3). Impaired hemodynamics and comorbidities were more frequent at time of referral in later eras, whereas other HF severity parameters where similar or improved. Successive eras had greater utilization of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, beta-blockers, aldosterone antagonists, implantable cardioverter defibrillators, and cardiac resynchronization therapy, consistent with evolving evidence and guideline-recommendations over the study period. All-cause mortality and sudden death were significantly lower in era 2 and 3 compared to era 1. After multivariable risk adjustment, era 3 had significantly decreased 2- and 3-year all-cause mortality risk and significantly decreased 1- and 3-year sudden death risk compared to era 1. However, progressive HF death and the combined outcome of mortality / urgent transplant / ventricular assist device were modestly increased in the latter eras. Conclusions Over the past two decades, patients with advanced HF referred to and managed at a tertiary university referral center have benefited from advances in HF medications and devices, as evidenced by improvements in overall survival and sudden death risk.