All-inside suture meniscal repair using suture passer

In recent years, to save the meniscus and prevent the progression of knee osteoarthritis, the indications for meniscus repair have been expanding instead of partial menisectomy. Accordingly, various repair techniques for meniscus tears have been developed. The conventional inside-out and outside-in meniscus repair techniques and all-inside repair technique with an implant/anchor can be classified as trans-capsular (TC) repair from the perspective of suture with penetrating capsule. Recently, new suture passers for all-inside meniscus repair have been developed. To distinguish from conventional all-inside repair with implant/anchors, all-inside repair with only suture using these suture passers was described as all-inside suture (AIS) repair. This AIS repair could achieve meniscus-to-meniscus suture across the tear without interposition of soft tissues including the capsule between suture and meniscus, leading direct gap closing of torn edges. In this respect, AIS repair is considered to be "anatomical meniscus repair". Actually, some reports showed biomechanical and clinical advantages of AIS repair. However, there is still limited evidence in clinical practice. Moreover, there are some disadvantages for AIS repair. Not only further studies but also development of new devices and surgical techniques for AIS should be required. This review describes the current status of AIS repair for each type of tear.