The concurrence of tears of the scapholunate (SL) and lunotriquetral (LT) ligaments is not unusual and can also occur without an apparent perilunate dislocation. Badia and Khanchandani called this combined lesion a "floating lunate" because the ligamentous attachments on both sides of the lunate are absent and the lunate floats in a neutral position. There have been few published papers referring to the treatment of this kind of instability. In recent years, we have developed an arthroscopic ligamentoplasty for SL instability. However, this procedure is not indicated whether the LT ligament is also damaged. With this current modification, both the strongest portions of the SL and LT ligaments can be reconstructed without opening the joint, thereby avoiding an open approach. We have described this as an "S"-shaped ligamentoplasty, as the graft resembles an "S" as it travels inside the scaphoid, lunate, and triquetrum. The same postoperative early mobilization protocol can be applied to this kind of reconstruction.