A recent trend in tissue anchor and suture anchor devices is the “soft” device, also referred to as a “filamentary” fixation device, in which the device itself is constructed of a filamentary material, such as suture or the like. Such filamentary fixation devices can replace traditional metal or hard polymer devices in numerous soft tissue repair and replacement surgical procedures. Such filamentary fixation devices may provide solutions to various problems encountered with traditional metal or hard polymer devices. In many instances, such traditional devices tend to be large in diameter, and must include sufficient material, or other additional structures, to withstand the forces pulling against the device, whether via a suture or directly against the device itself. The size of such devices may limit the possible implantation locations in the body, as sufficient bone mass is required to accommodate the device. Moreover, a large hole must be drilled into the bone to allow for passage of the device through the cortical layer and into the cancellous bone. The larger drill holes may be too invasive resulting in excessive loss of healthy bone, or creation of a large repair site.
Despite the many benefits these filamentary fixation devices provide, such devices to date cannot be used to perform knotless surgical procedures, that is, surgical procedures using filaments (such as sutures or the like) where the filament is secured without the need of tying knots, such as half hitches or the like. Such surgical procedures are beneficial as knots have the tendency to loosen over time, thereby reducing the likelihood of a successful repair. Additionally, knot tying can take up an inordinate amount of time during a surgical procedure, as well as making the suture more susceptible to breakage, particularly at the location of the knot itself, which is commonly known as a weak point of surgical repairs. Furthermore, the stack of knots that is created after tying the sufficient amount of half hitches or the like can be undesirable as they interface with surrounding anatomy such as tissue, bone, and cartilage. Therefore, there is a need for improved filamentary fixation devices capable for use in knotless surgical procedures.