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There has been an increased interest in the quantification of the knee laxity secondary to anterior cruciate ligament (ACL) injury. In clinical practice, the diagnosis is performed by clinical examination and magnetic resonance imaging analysis and confirmed arthroscopically. The pivot shift phenomenon has been identified as one of the essential signs of functional ACL insufficiency. A reliable system to adequately assess patients with ACL injury, quantifying the pivot shift test outcome, is needed. Several studies have been conducted in this regard but the proposed methods remain confined to a research area. The goal of this article is to summarize the actual knowledge and current concepts.

The purpose of this study was to evaluate the clinical outcomes after arthroscopic management of irreducible posterolateral knee dislocation. Twenty-one patients with irreducible posterolateral knee dislocation were treated in our institution from January 2009 to May 2014. Inclusion criteria were as follows: (1) patients who underwent one-stage arthroscopic reduction combined with multiligament reconstruction or repair and (2) patients with a minimum 2-year follow-up. Knee stability was assessed using physical examination and side-to-side differences (SSD) determined with a KT-1000 arthrometer and Telos stress device. Other assessments included the International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner score, and patient satisfaction rate. Thirteen of the 21 patients (8 males and 5 females) met our inclusion criteria and were included in this analysis. The mean age was 37.8 years (range, 27-56 years). The mean time from injury to surgery was 1.84 days (range, 1-3 days). The mean follow-up period was 32.6 months (range, 24-46 months). At the final follow-up, with the exception of one patient who had an abnormal valgus stress test, all patients achieved normal or nearly normal Lachman test, pivot shift test, posterior drawer test, and varus and valgus stress tests. The mean SSD of total anterior-posterior translation and isolated anterior translation determined with a KT-1000 arthrometer were 2.15 ± 1.57 mm (range, 0-6 mm) and 1.61 ± 0.86 mm (range, 1-4 mm), respectively. The mean SSD of anterior translation, posterior translation, and medial and lateral joint gapping determined with a Telos stress device were 2.23 ± 0.92 mm (range, 1-4 mm), 3.23 ± 1.16 mm (range, 2-5 mm), 1.77 ± 1.87 mm (range, 0-7 mm), and 0.46 ± 0.52 mm (range, 0-2 mm), respectively. The IKDC subjective score, Lysholm score, and Tegner score improved significantly postoperatively (p = 0.001) with a satisfaction rate of 84.6%. One-stage arthroscopic reduction combined with multiligament reconstruction or repair was an effective, reliable treatment for irreducible posterolateral knee dislocation. This is a case series with level of evidence as IV.

A deep lateral femoral notch (LFN) on lateral radiographs is indicative of ACL injury. Prior studies have suggested that a deep LFN may also be a sign of persistent rotatory instability and a concomitant lateral meniscus tear. Therefore, the purpose of this study was to evaluate the relationship between LFN depth and both quantitative measures of rotatory knee instability and the incidence of lateral meniscus tears. It was hypothesized that greater LFN depth would be correlated with increased rotatory instability, quantified by lateral compartment translation and tibial acceleration during a quantitative pivot shift test, and incidence of lateral meniscus tears.

The purpose of this observational study was to determine which factors, including sex, are associated with increased rotatory knee laxity in collegiate athletes with no history of knee injuries. It was hypothesized that increased rotatory knee laxity, measured by a quantitative pivot shift test, would correlate with female sex, increased anterior translation during the Lachman test, generalized ligamentous laxity, and knee hyperextension.

The role of the anterolateral capsule complex in knee rotatory stability remains controversial. Therefore, the objective of this study was to determine the in-situ forces in the anterior cruciate ligament (ACL), the anterolateral capsule, the lateral collateral ligament (LCL), and the forces transmitted between each region of the anterolateral capsule in response to a simulated pivot shift test. A robotic testing system applied a simulated pivot shift test continuously from full extension to 90(o) of flexion to intact cadaveric knees (n = 7). To determine the magnitude of the in-situ forces, kinematics of the intact knee were replayed in position control mode after the following procedures were performed: 1) ACL transection, 2) capsule separation, 3) anterolateral capsule transection and 4) LCL transection. A repeated measures ANOVA was performed to compare in-situ forces between each knee state (*p < 0.05). The in-situ force in the ACL was significantly greater than the forces transmitted between each region of the anterolateral capsule at 5(o) and 15(o) of flexion but significantly lower at 60(o) , 75(o) and 90(o) of flexion. This study demonstrated that the ACL is the primary rotatory stabilizer at low flexion angles during a simulated pivot shift test in the intact knee, but the anterolateral capsule plays an important secondary role at flexion angles greater than 60°. Furthermore, the contribution of the "anterolateral ligament" to rotatory knee stability in this study was negligible during a simulated pivot shift test. This article is protected by copyright. All rights reserved.

Ultrasound (US) examination of the anterolateral ligament (ALL) in the anterior cruciate ligament-deficient knee betters magnetic resonance imaging analysis with slightly higher identification rate of the entire ALL presumably due to the ability to test in a functional pivot shift configuration. The ALL was injured in 63% of the anterior cruciate ligament-deficient knees and the injury occurred at the tibial insertion in all cases. Although the authors propose US to be the new “gold standard” for diagnosing ALL injuries, there still remains a question of whether there is any necessity for an US diagnosis of ALL injury when the pivot shift test may provide the necessary information, and the consensus for ALL reconstruction or lateral extra-articular tenodesis has yet to be reached.

The pivot shift test is performed in different techniques and the rotation of the tibia seems to have a significant impact on the amount of the pivot shift phenomenon. It has been hypothesised that external rotation will increase the phenomenon due to less tension at the iliotibial band in knee extension.

The pivot shift test is the most specific clinical test to detect anterior cruciate ligament injury. The purpose of this study was to determine the correlation between the 2D simple image analysis method and the 3D bony motion of the knee during the pivot shift test and assess the intra- and inter-examiner agreements.

The main goal of this work was to evaluate the pivot shift test in awake and anesthetized patients by using two different quantitative methodologies and comparing the results with the standard clinical grading, taking advantage of a multicenter international study.

The pivot shift test is an important clinical tool used to assess the stability of the knee following an injury to the anterior cruciate ligament (ACL). Previous studies have shown that significant variability exists in the performance and interpretation of this manoeuvre. Accordingly, a variety of techniques aimed at standardizing and quantifying the pivot shift test have been developed. In recent years, inertial sensors have been used to measure the kinematics of the pivot shift. The goal of this study is to present a review of the literature and discuss the principles of inertial sensors and their use in quantifying the pivot shift test.