Menisco-ligamentous injuries of knee joint: Can ultrasonography serve as an effective screening modality?

The aim is to calculate sensitivity, specificity and diagnostic accuracy of Ultrasonography (USG) as a screening modality in evaluation of Menisco- Ligamentous injuries of knee joint with Magnetic Resonance Imaging (MRI)as gold standard for comparison.Patients with clinically suspected Menisco-Ligamentous injurieswere evaluated by USG initially followed by MRI on the same day. A total of 60 patients (50 males, 10 females) underwent USG and MRI. USG was done using high frequency probe (9-14 Hz) and all the injuries noted. USG of the normal knee was done for comparison. MRI with trauma protocol sequences was done on the same day. The accuracy of USG and MRI in diagnosis of menisco-ligamentous injuries was compared. Majority of the patients (50%) belonged to age group of 21-40 years. Most common injuries seen were medial meniscal tear followed by medial collateral ligament injury. The strength of agreement between USG and MRI was good with Diagnostic accuracy of USG ranging from 83.3% to 95% for different meniscal/ligamentous injuries.USG is an effective imaging modality with high accuracy in diagnosing menisco-ligamentous injuries. USG can act as an effective screening modality in closed knee trauma for evaluation of menisco- ligamentous injuries especially in resource constrained regions owing to its easy availability, portability and lower cost. MRI can be reserved for patients with suspicious USG and clinical findings.

In Vivo biomechanical evaluations of suture anchors for repairing grade 3 superficial medial collateral ligament injury in a porcine model

Purpose: To clarify the biomechanical and radiological outcomes of superficial medial collateral ligament (sMCL) repair using suture anchors in a large animal model. Methods: The right sMCLs of nine male castrated pigs was completely detached at the femoral attachment. sMCL repair surgery was performed using two suture anchors. The same skin incision, sMCL exposure, and immediate wound closure were made at the left knee as a sham surgery. Magnetic resonance imaging was performed preoperatively and 4 weeks after surgery. The structural properties (upper yield load, maximum load, linear stiffness, and elongation at failure) of the femur-sMCL-tibia complex were determined. Results: During tensile testing, all the repaired sMCLs avulsed from the femoral attachment. There were no significant differences in the upper yield load, maximum load, linear stiffness, or elongation at failure between the groups 4 weeks after surgery or in the MRI-derived signal-to-noise quotients (SNQs) at the mid and tibial sMCL. The SNQs differed significantly at the femoral (2.7 ± 1.2 vs 0.3 ± 0.7; P = 0.00064) portions between groups. Conclusion: The injured sMCLs biomechanically recovered after surgery using suture anchors even though the SNQs were higher than those with native contralateral sMCLs. For clinical relevance, sMCL repair of grade 3 sMCL injuries using suture anchors was both safe and successful with less tissue dissection.

Differential expression of related molecules after acute injury of rabbits’ anterior cruciate ligament and medial collateral ligament

Objective: This study aimed to assay expression of the mRNA and proteins for injuring- and angiogenesis-associated molecules at 3 days, 1week, 2weeks, 4weeks and 6 weeks after anterior cruciate ligament or medial collateral ligament injury in male New Zealand White rabbits.Methods: Models similar to those of clinical patients were used to establish acute partial injuries of the anterior cruciate ligament and medial collateral ligament at 3 days, 1 week, 2 weeks, 4 weeks and 6 weeks and normal control groups. Molecular biological changes in male rabbits were detected at different time points after anterior cruciate ligament and medial collateral ligament injury by H&E staining, reverse transcriptase chain reaction and westren blotting.Results: Marked differences were found in the postinjury changes in gene levels and proteins in the anterior cruciate ligament compared to the medial collateral ligament. There was no increase in mRNA expression of TIMP3, TGF-βand PRG4 in the injured anterior cruciate ligament at any time point. However, the levels of these genes tended to increase in the injured medial collateral ligament. In contrast, MMP-13 mRNA levels were significantly increased in the injured anterior cruciate ligament, but not in the medial collateral ligament. Furthermore, vascular endothelial growth factor decreased following injury to both the anterior cruciate ligament and medial collateral ligament, with the difference being a slight decrease in the medial collateral ligament and a significant decrease in the anterior cruciate ligament. Similarly, protein blots showed higher protein expression of type I and type III collagen in the injured medial collateral ligament than in the anterior cruciate ligament.Conclusion: The results show that there were drastic differences in angiogenesis, collagen and Matrix metalloproteinases after anterior cruciate ligament and medial collateral ligament injury. It can be found that the repair ability of the anterior cruciate ligament and medial collateral ligament after injury may be related to the differences in molecular expression.