Punctate depressions, cartilage erosion, and bone destruction were observed in the MIA-induced arthritis model. The macroscopic cartilage and bone scoring enabled the quantification of cartilage degeneration and demonstrated that MIA-induced arthritis progressed in a dose- and time-dependent manner. IFP inflammation scores revealed that 0.2 mg MIA induced reversible synovitis, while 1 mg MIA induced fibrosis of the IFP body.

III.

The meniscus roots are critical for meniscus function in preserving correct knee kinematics and avoiding meniscus extrusion and, consequently, in the progression of osteoarthritis. Several techniques exist for medial meniscus posterior root tear repair; however, current surgical techniques have been proved to fail to reduce meniscus extrusion, which has been shown to be associated with development of osteoarthritis, although significant improvements in the postoperative clinical findings have been achieved. This Technical Note describes an arthroscopic technique for the medial meniscus posterior root tear in which a pullout repair is augmented by a centralization technique to restore and maintain the medial meniscus function by efficiently reducing meniscus extrusion.

II.

No abstract

We developed medial meniscus extrusion in a rat model, and centralization of the extruded medial meniscus by the pull-out suture technique improved the medial meniscus extrusion and delayed cartilage degeneration, though the effect was limited. Centralization is a promising treatment to prevent the progression of osteoarthritis.

Background: Several types of anterolateral structure (ALS) augmentation procedures in anterior cruciate ligament (ACL) reconstruction have been reported. However, information is limited regarding the effect of additional ALS augmentation on rotatory stability in a clinical setting. Purpose/Hypothesis: This study aimed to investigate the contribution of additional ALS augmentation in ACL reconstruction in cases with a high risk of residual pivot shift. The 2 hypotheses were as follows. First, additional ALS augmentation would improve rotatory stability as compared with solely reconstructing the ACL. Second, graft tension changes would be different between the ACL and ALS during knee range of motion and against anterior or rotatory loads. Study Design: Controlled laboratory study. Methods: Fifteen patients who met at least 1 of the following criteria were included: (1) revision ACL reconstruction, (2) preoperative high-grade pivot shift, or (3) hyperextended knee. The pivot-shift test was performed preoperatively and during surgery after ACL reconstruction and after additional ALS augmentation with acceleration measurements from a triaxial accelerometer. The tension changes of the ACL and ALS grafts were also measured during knee range of motion and against manual maximum anterior tibial translation, internal rotation, and external rotation. Results: After ACL reconstruction, the pivot-shift acceleration was still greater than that of the uninjured knee. However, additional ALS augmentation further reduced acceleration when compared with ACL reconstruction alone in both primary and revision cases ( P < .05 vs preoperative, P < .05 vs ACL). During knee flexion-extension, the tension of the ACL increased as the knee was extended, whereas that of the ALS did not change. Graft tension of the ACL and ALS became higher with internal rotation and lower with external rotation as compared with the neutral position. Tension of the ACL was significantly increased against anterior tibial translational loads, whereas that of the ALS was not. Conclusion: Additional ALS augmentation further improved the rotatory stability during ACL reconstruction in patients with a high risk of residual pivot shift at the time of surgery. Significant differences in graft tension changes were also observed between the ACL and ALS against different loads. Additional ALS augmentation may be considered to eliminate the pivot shift in patients with a high risk of residual pivot shift.

Purpose The anterior cruciate ligament‐return to sports after injury (ACL‐RSI) scale assesses the psychological impact of returning to sports (also referred to as psychological readiness) after ACL reconstruction. The aim of this study was to evaluate important measurement properties of the Japanese version of ACL‐RSI scale. Methods Ninety‐three participants who underwent ACL reconstruction filled out the Japanese version of ACL‐RSI scale, the Tampa scale for kinesiophobia (TSK), the International Knee Documentation Committee‐Subjective Knee Form (IKDC‐SKF), and Knee injury and Osteoarthritis Outcome Score (KOOS). To assess test re‐test reliability, 50 of the 93 participants re‐answered the Japanese version of ACL‐RSI scale within 10 days. Floor and ceiling effects, internal consistency, construct validity, and reliability of the Japanese version of ACL‐RSI scale were analysed. Results There were no floor and ceiling effects. The Japanese version of ACL‐RSI scale showed good internal consistency (Cronbach's alpha = 0.912). It was positively correlated with total points of IKDC‐SKF and the Lysholm score, and with the all sub‐categories of the KOOS, and it was negatively correlated with the TSK. Reliability of the Japanese version of ACL‐RSI scale was satisfactory. Conclusion The Japanese version of ACL‐RSI scale has acceptable measurement properties. It can be a useful for evaluation of psychological readiness for return to sports in Japanese athletes who undergo primary ACL reconstruction. Information provided by the Japanese version of the ACL‐RSI scale may also help to identify athletes who find return to sport a challenge, and guide conversations regarding treatment and rehabilitation plans. Level of evidence II.