Arthroscopic Fixation of Tibial Eminence Fractures: A Biomechanical Comparative Study of Screw, Suture, and Suture Anchor.

PURPOSE: To compare biomechanical outcomes of 4 different arthroscopic techniques for fixation of tibial eminence fractures.

METHODS

Twenty-four skeletally mature, fresh-frozen cadaveric knees were divided into 4 comparison groups based on the fixation method: screw fixation (group A), traditional sutures fixation with 2 FiberWire sutures (group B), a modified suture technique with 2 FiberWire sutures that created neckwear knots to firmly trap the fracture fragment (group C), or suture anchors which was based on the suture bridge technique primarily used in the shoulder for repair of rotator cuff tears and greater tuberosity fractures (group D). A tibial eminence fracture was created in each knee for subsequent fixation. After fixation, each knee underwent cyclic loading of 100 N to assess the displacement change after 500 cycles of the fixation construct. Afterward, a single tensile failure test load was performed to assess the ultimate failure load, stiffness, and failure mode for each specimen.

RESULTS

All specimens survived cyclic testing and were subsequently loaded to failure. Group C had the highest ultimate failure load (P < .05) and group D had the lowest displacement compared with the other 3 groups (P < .05). Different failure modes were found among the 4 groups.

CONCLUSIONS

Suture fixation using the neckwear knots technique provides superior fixation with regard to higher ultimate failure load, and absorbable suture anchor fixation with the suture bridge technique provides less displacement under cyclic loading conditions. Both techniques exhibited superior biomechanical properties compared with traditional screw and suture fixation.

CLINICAL RELEVANCE: The new techniques showed satisfactory biomechanical properties and provided more choice for surgeons in the treatment of tibial eminence fractures.