Biomechanical Performance of Hip Labral Repair Techniques.

PURPOSE

To determine the strength of various suture techniques and the impact of suture passer size on cyclically loaded hip labra.

METHODS

We assigned 63 bovine hip labra to 9 simple knotless suture technique groups using OrthoCord suture: (1) penetrating grasper (2.6 mm)-placed horizontal mattress, (2) penetrating grasper-placed vertical mattress, (3) SutureLasso (1.8 mm)-placed vertical mattress, (4) penetrating grasper-placed oblique repair, (5) penetrating grasper-placed vertical mattress plus radiofrequency, (6) SutureLasso-placed horizontal mattress, (7) SutureLasso-placed oblique mattress, (8) SutureLasso-placed horizontal mattress plus radiofrequency, and (9) SutureLasso-placed oblique mattress plus radiofrequency. After 20 cycles of uniaxial tensile loading (5 to 80 N), destructive testing was performed.

RESULTS

Penetrating grasper-placed horizontal mattress sutures showed lower ultimate failure loads than vertical and oblique mattress sutures (P < .05). Penetrating grasper-placed vertical mattress sutures had higher peak-to-peak displacement than SutureLasso-placed vertical mattress sutures (P = .04). SutureLasso-placed oblique mattress sutures had a higher ultimate load (P < .01) and stiffness (P = .04) than SutureLasso-placed horizontal mattress sutures. SutureLasso-placed horizontal mattress sutures had lower cyclic elongation than penetrating grasper-placed horizontal mattress sutures (P = .01) and lower ultimate load (P < .01) and stiffness than SutureLasso-placed vertical mattress sutures (P < .01). Horizontal mattress sutures with radiofrequency had a higher ultimate load (P = .02), stiffness, and cyclic elongation (P < .01) than without radiofrequency.

CONCLUSIONS

A horizontal mattress hip labrum stitch shows a lower ultimate failure load than vertical or oblique mattress stitches. Smaller-diameter suture-passing devices show less cyclic displacement and elongation than larger-diameter devices. Radiofrequency labral treatment does not alter vertical stitch strength but does alter horizontal mattress stitch strength.

CLINICAL RELEVANCE

Vertical and oblique stitches are stronger than horizontal stitches. A 1.8-mm passing device shows a better cyclic loading performance than a 2.6-mm device.