Modified Outside-In Plus Suture Technique for Repair of the Anterior and Middle Segments of the Meniscus: Technical Note.

Traditionally, an outside-in suture technique is appropriate to repair longitudinal tears of the anterior and middle segments of the meniscus. However, it has a fundamental weakness of not creating a vertical mattress-type suture. To overcome this weakness, the modified outside-in technique was developed using a suture hook to create a vertical mattress-type suture in the inner fragment. However, it still has the disadvantage of requiring an open skin incision to prevent neurovascular damage during knot tying. Thus, we developed the modified outside-in plus technique to make a vertical mattress suture without an open skin incision in the knee joint. With this technique, the use of both vertical and horizontal mattress sutures is possible. Although this technique is similar to the modified outside-in technique, a suture knot is made inside the knee joint. Therefore, it compensates for the disadvantage of the outside-in technique. The modified outside-in plus technique is able to achieve good reduction and sufficient stability through a vertical mattress suture technique without additional skin incisions.

Is the popliteus tendon always inserted antero-inferiorly 18.5 mm from the lateral collateral ligament of the femur? Magnetic resonance imaging and cadaveric evaluations.

BACKGROUND: The aim of this study was to analyze the locations of the femoral attachments of the popliteus tendon (PT) and lateral collateral ligament (LCL) via magnetic resonance imaging (MRI) and cadaveric dissection in a Korean population and compare with literature standards to determine whether variability exists. METHODS: We retrospectively analyzed knee MRIs from 87 cases selected from January 2017 to December 2018. The relationship between the femoral attachment of PT and LCL was analyzed by MRI using PACS and Image J. In addition, the femoral attachments of each structure were identified and marked in 14 unpaired human cadaveric knees. Three-dimensional models were reconstructed, and the surface area, location and distances were analyzed. RESULTS: On MRI, the femoral attachment of PT was located at mean distances of 0.89 mm posterior and 9.35 mm inferior to the LCL femoral attachment. We identified three groups of PT locations relative to the LCL on MRI evaluation: parallel (63%), posterior (29%), and anterior (8%). On cadaveric evaluation, the femoral attachment of the PT was located at mean distances of 0.77 mm posterior and 8.90 mm inferior to the LCL femoral attachment. We also identified three groups of PT locations relative to the LCL on cadaveric evaluation: parallel (43%), posterior (36%), and anterior (21%). CONCLUSIONS: Based on both MRI and cadaveric evaluations in a Korean population, the femoral attachment of the PT is located just distal to and posterior to the LCL. The differences between the centroids of the femoral attachments of the two structures was approximately 9.7 mm, suggesting that racially based anatomical differences of the posterolateral corner may exist.