Triple-loaded single-anchor stitch configurations: an analysis of cyclically loaded suture-tendon interface security.
OBJECTIVE
This study evaluated the strength and suture-tendon interface security of different suture configurations from triple-suture-loaded anchors.


METHODS
A juvenile bovine infraspinatus tendon was detached and repaired by use of 4 different suture combinations from 2 suture anchors: 3 simple sutures in each anchor (ThreeVo anchor; Linvatec, Largo, FL); 2 peripheral simple stitches and 1 central horizontal mattress suture passed deeper into the tendon, creating a larger footprint (bigfoot-print anchor); 2 peripheral simple stitches with 1 central horizontal mattress stitch passed through the same holes as the simple sutures (stitch-of-Burns); and 2 simple stitches (TwoVo anchor; Linvatec). The constructs were cyclically loaded between 10 N and 180 N for 3,500 cycles and then destructively tested. The number of cycles required to create a 5-mm gap and a 10-mm gap and the ultimate load to failure and failure mode were recorded.


RESULTS
The ThreeVo anchor was strongest and most resistant to cyclic loading (P < .01). The TwoVo anchor was least resistant to cyclic loading. The stitch-of-Burns anchor was more resistant to cyclic loading than both the bigfoot-print anchor and the TwoVo anchor (P < .03). The ThreeVo, stitch-of-Burns, and TwoVo anchors were stronger than the bigfoot-print anchor (P < .05).


CONCLUSIONS
Three simple sutures in an anchor hold better than two simple sutures. Three simple sutures provide superior suture-tendon security than combinations of one mattress and two simple stitches subjected to cyclic loading. A central mattress stitch placed more medially than two peripheral simple stitches (bigfoot-print anchor) configured to enlarge the tendon-suture footprint was not as resistant to cyclic loading or destructive testing as three simple stitches (ThreeVo anchor).


CONCLUSIONS
Placing a central mattress stitch more medially than 2 peripheral simple stitches to enlarge the tendon-suture footprint was not as resistant to cyclic loading or destructive testing as 3 simple stitches.
Coons
David A
DA
Plano Orthopedic and Sports Medicine Center, 5228 West Plano Pkwy, Plano, TX 75093, USA.
Barber
F Alan
FA
Herbert
Morley A
MA
D000818:Animals; D002417:Cattle; D008422:Materials Testing; D017006:Rotator Cuff; D053441:Suture Anchors / Q000592:standards*; D013536:Suture Techniques / Q000592:standards*; D013537:Sutures; D013710:Tendons / Q000601:surgery*; D013718:Tensile Strength