The inside-out technique is a method of repairing a torn meniscus where the sutures are introduced from inside the joint and secured on the outside of the capsule.
Commercial cannulae, called zone-specific cannulae, create a path for long flexible needles pre-loaded with sutures to be passed into the meniscus arthroscopically from the anterolateral portal and then out through the capsule, to be retrieved by an assistant.
The technique can be used for all tears except very posterior ones. It has the highest mechanical strength of the three alternatives (inside-out, outside-in and all-inside), but has been largely replaced by the simpler 'all inside' technique.
See video: https://www.youtube.com/watch?v=OxAPhxjkDCI
Inside-Out Meniscal Repair: Medial and Lateral Approach. Chahla J, Cruz RS, Cram TR, Dean CS and LaPrade RF. Arthrosc Tech. 2016 Feb; 5(1): e163–e168.