Comparison of the mechanical properties of different tension band materials and suture techniques.
OBJECTIVE
This study determined the tensile properties of 18-gauge stainless steel wire, 5-mm woven polyester (Mersilene) tape, and multiple loop configurations of No. 5 braided polyester suture (Ethibond).


METHODS
Mechanical property testing.


METHODS
Single loops of stainless steel wire, Mersilene, and Ethibond were tested to determine their mechanical properties. Ethibond was tested with different numbers of loops and different knot configurations.


METHODS
Stiffness, load at failure, and elongation at failure.


RESULTS
One loop of Mersilene and two loops of Ethibond had similar loads at failure, but the load at failure was significantly higher for stainless steel wire. Four loops of Ethibond withstood a similar failure load to stainless steel wire, but the failure load of the Ethibond suture was greater than the yield load of stainless steel wire. Stainless steel wire had a higher stiffness than both Ethibond and Mersilene. No difference was found in the failure load between different Ethibond knot configurations. The individually tied suture configuration resulted in a higher stiffness than the single-knot configuration. The elongation at failure was not statistically different among the different knot configurations and materials, with the exception of Mersilene tape. Mersilene tape demonstrated a significant increase in elongation at failure as compared to the other materials and knot configurations.


CONCLUSIONS
It appears that multiple loops of Ethibond can substitute for stainless steel wire in situations where a compliant repair is suitable (support of a patellar tendon repair), but may not be satisfactory for rigid fixation (tension band fixation of a fracture). There appears to be no significant difference in strength but a small decrease in stiffness between tying multiple suture loops in one knot as opposed to individual knots.
Harrell
R M
RM
Department of Orthopaedic Surgery, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7055, USA.
Tong
J
J
Weinhold
P S
PS
Dahners
Laurence E
LE
D005592:Fracture Fixation; D050723:Fractures, Bone / Q000601:surgery*; D006801:Humans; D011093:Polyethylene Terephthalates; D013193:Stainless Steel; D013314:Stress, Mechanical; D013536:Suture Techniques; D013537:Sutures; D013718:Tensile Strength
C014534:Ethibond; D011093:Polyethylene Terephthalates; D013193:Stainless Steel; C025539:Lavsan