The biomechanical effects of polytetrafluoroethylene suture augmentations in lateral-row rotator cuff repairs in an ovine model.
BACKGROUND
This study investigated the biomechanical effects of expanded polytetrafluoroethylene (ePTFE) suture augmentation patches in rotator cuff repair constructs.


METHODS
The infraspinatus tendon in 24 cadaveric ovine shoulders was repaired using an inverted horizontal mattress suture with 2 knotless bone anchors (ArthroCare, Austin, TX, USA) in a lateral-row configuration. Four different repair groups (6 per group) were created: (1) standard repair using inverted horizontal mattress sutures, (2) repair with ePTFE suture augmentations on the bursal side of the tendon, (3) repair with ePTFE suture augmentations on the articular side, and, (4) repair with ePTFE suture augmentations on both sides of the tendon. Footprint contact pressure, stiffness, and the load to failure of the repair constructs were measured.


RESULTS
Repairs with ePTFE suture augmentations on the bursal side exerted significantly more footprint contact pressure (0.40 ± 0.01 MPa) than those on the articular side (0.34 ± 0.02 MPa, P = .04) and those on both sides (0.33 ± 0.02 MPa, P = .01). At 15 degrees of abduction, ePTFE-augmented repairs on the bursal side had higher footprint contact pressure (0.26 ± 0.03 MPa) compared with standard repairs (0.15 ± 0.02 MPa, P = .01) and with ePTFE-augmented repairs on the articular side (0.18 ± 0.02 MPa, P = .03). The ePTFE-augmented repairs on the bursal side demonstrated significantly higher failure loads (178 ± 18 N) than standard repairs (120 ± 17 N, P = .04).


CONCLUSIONS
Inverted horizontal mattress sutures augmented with ePTFE patches on the bursal side of the tendon enhanced footprint contact pressures and the ultimate load to failure of lateral-row rotator cuff repairs in an ovine model.
Sports Medicine and Shoulder Service, Department of Orthopaedic Surgery, St George Hospital Campus, University of New South Wales, Sydney, NSW, Australia. Electronic address: orthopeed@gmail.com.
Lijkele
L
Beimers
Sports Medicine and Shoulder Service, Department of Orthopaedic Surgery, St George Hospital Campus, University of New South Wales, Sydney, NSW, Australia.
Patrick H
PH
Lam
Sports Medicine and Shoulder Service, Department of Orthopaedic Surgery, St George Hospital Campus, University of New South Wales, Sydney, NSW, Australia.
George A C
GA
Murrell
D000818:Animals; D001696:Biomechanical Phenomena; D004195:Disease Models, Animal; D011138:Polytetrafluoroethylene; D017006:Rotator Cuff / Q000503:physiopathology / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D012756:Sheep; D013536:Suture Techniques; D013537:Sutures
D011138:Polytetrafluoroethylene
Rotator cuff repair; expanded polytetrafluoroethylene; ovine model; patch augmentation