- Post Fixation:
- w/ BPB grafts, the sutures are passed thru the bone plug and then are passed around a screw over a washer;
- w/ soft tissue grafts (such as tendinous edge of Achilles tendon graft), requires a Krackow stitch (whiped locking stitch) is required;
- Spiked Washer Fixation:
- allows secure fixation of soft tissue w/o necrosing tissue;
- a whipped locking stitch is inserted into the tendon end, and is tied around the screw prior to final tightening of the screw;
- Button Fixation:
- sutures are passed thru a ligament button and tied under tension;
- the suture ends are then passed under a staple to prevent excess motion while the graft material heals into the tunnel surface;
- Interference Screw Fixation:
- may provide most stable fixation;
- interference screw threads may cut into bone plug sutures, especially when they the screw comes into the cortical surface of the bone plug;
- screw threads may cut into tendinous portion of the graft if it is advanced too far into the tibial tunnel;
- Staple Fixation:
- may cause pressure necrosis and early graft failure;
- prior to stapling a trough should be cut into the underlying bone