Os acromiale fixation: a biomechanical comparison of polyethylene suture versus stainless steel wire tension band

• Published in: Journal of shoulder and elbow surgery 2016-12, Vol.25 (12), p.2034-2039
• Main Authors: Shiu, Brian, MD, Song, Xuyang, MD, Iacangelo, Abigail, BS, Kim, Hyunchul, MS, Jazini, Ehsan, MD, Henn, R. Frank, MD, Gilotra, Mohit N., MD, Hasan, S. Ashfaq, MD
• Format: Article
• Language: English
• Subjects: Acromion - surgery; Aged; Aged, 80 and over; Biomechanical Phenomena; Biomechanics; Bone Screws; Bone Wires; Cadaver; Female; Humans; Joint Instability - surgery; Male; Materials Testing; Middle Aged; Orthopedics; Os acromiale; Polyethylene suture; Polyethylenes; Shoulder Joint - surgery; Stainless Steel; Stainless steel wire; Suture tension band; Sutures; Tension band
• ISSN: 1058-2746; 1532-6500
• DOI: 10.1016/j.jse.2016.04.028

Background Symptomatic hardware is a commonly reported complication after surgical fixation of an unstable meso-type os acromiale. This study compared the biomechanical properties of a cannulated screw tension band construct using a metal wire tension band vs. a suture tension band, considering that the suture construct could allow for decreased hardware burden in the clinical setting. Methods A meso-type os acromiale was created in 16 cadaveric shoulders. Two cannulated 4-mm screws were placed in each specimen. Tension band augmentation was accomplished with a 1-mm stainless steel wire (wire group) or a #5 braided polyethylene suture (suture group), with 8 specimens in each group. An inferiorly directed force was applied to the anterior acromion at 1 mm/s on a materials testing machine. Stiffness and ultimate failure load were recorded and analyzed. Results No significant difference ( P  = .22) was observed in the ultimate failure load between the wire (228  ± 85 N; range, 114-397 N) and the suture (275 ± 139 N; range, 112–530 N). No significant difference ( P  = .17) was observed in the stiffness between the wire (28  ± 12 N/mm; range, 18–53 N/mm) and the suture (38  ± 25 N/mm; range, 10–83 N/mm). Conclusions Stainless steel wire and polyethylene suture have similar biomechanical strength in the cannulated screw tension band fixation of meso-type os acromiale at time zero.