A 'harpoon' in knee surgery is the term sometimes given to small bio-degradeable barbed devices which are shot through the two parts of a torn meniscus to hold the fragments together.
Seldom used now
A suture may have been attached to the harpoon - but the procedure has largely been superceded by newer techniques because the devices may sometimes cause problems within the joint.
All-inside Arthroscopic Meniscal Repair Technique Using a Midbody Accessory Portal. Hendrix ST, Kwapisz A and Wyland, DJ. Arthrosc Tech. 2017 Oct; 6(5): e1885–e1890.