Polymers in Medicine
2016, vol. 46, nr 2, July-December, p. 111–116
doi: 10.17219/pim/68735
Publication type: original article
Language: English
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The Stress Relaxation Process in Sutures Tied with a Surgeon’s Knot in a Simulated Biological Environment
1 Institute of Applied Mechanics, Cracow University of Technology, Kraków, Poland
Abstract
Background. The exact characteristics of sutures are not only the basis for selecting from among different types of suture, but also provide the necessary information for the design of new surgical sutures. Apart from information relating to the breaking load of a suture reported in pharmacopoeias, the viscoelastic properties of sutures can be an additional selection criterium – one that influences stitching quality, especially when there is a risk of wound dehiscence.
Objectives. The aim of the study was to assess the stress relaxation process for 3 polymeric sutures in an environment simulating the conditions in a living organism and (for comparison) in room conditions.
Material and Methods. Stress relaxation testing was carried out on 3 polymeric sutures: polypropylene (PP), polydioxanone (PDS) and polyglycolic acid (PGA). To identify the mechanical properties of the sutures, uniaxial tensile tests were conducted according to the Polish Pharmacopoeia. The relaxation test was carried out in room conditions and in the bath simulating a biological environment. The sutures being tested were tied with a surgeon’s knot.
Results. The PP suture exhibited the greatest stress relaxation (18% of the initial stress in room conditions and 21% of the initial stress in the bath). The PGA suture exhibited the least stress relaxation (approximately 60% of the initial stress in room conditions and 59% of the initial stress in the bath). The PDS suture was tested at a lower strain level and showed stress relaxation similar to the PGA suture (approximately 63% of the initial stress in room conditions and 55% in the bath).
Conclusion. Multifilament braided absorbable (PGA) sutures and monofilament absorbable (PDS) sutures had a higher stress relaxation ratio over time than monofilament non-absorbable (PP) sutures. These findings may indicate higher stress maintained over time in PDS and PGA sutures, and thus higher tension at wound edges, sufficient to resist wound dehiscence.
Key words
mechanical properties, stress relaxation, residual stress, polymeric sutures, surgeon’s knot
References (11)
- Farmakopea Polska IX, Urząd Rejestracji Produktów Leczniczych, Wyrobów Medycznych i Produktów Biobójczych, Warszawa 2011.
- Wesołowski P., Bakuniak P., Iwanowski K., Kresa I., Wojtowicz A.: Porównanie wytrzymałości mechanicznej wybranych nici stosowanych w chirurgii stomatologicznej. Nowa Stomatologia 2012, 1, 3–7.
- Zurek M., Kajzer A., Basiaga M., Jendruś R.: Właściwości wytrzymałościowe wybranych polimerowych nici chirurgicznych. Polimery 2016, 61(5), 334–338.
- Chu C.C.: Mechanical properties of suture materials: An important characterization. Ann. Surg. 1981, 193(3), 365–371.
- Naleway S.E., Lear W., Kruzic J.J., Maughan C.B.: Mechanical properties of suture materials in general and cutaneous surgery. J. Biomed. Mater. Res. Part B, Appl. Biomater. 2015, 103(4), 735–42.
- Sardenberg T., Muller S.S., de Almeida Silvares P.R., Mendonca A.B., de Lima Moraes R.R.: Assessment of mechanical properties and dimensions of suture threads utilized in orthopedic surgeries. Acta Ortoped. Bras. 2003, 11(2).
- Vizesi F., Jones C., Lotz N., Gianoutsos M., Walsh W.R.: Stress relaxation and creep: Viscoelastic properties of common suture materials used for flexor tendon repair. J. Hand Surg. 2008, 33(2), 241–246.
- Metz S.A., von Fraunhofer J.A., Masterson B.J.: Stress relaxation of organic suture materials. Biomater. 1990, 11(3), 197–199.
- Deng M., Zhou J.: Effects of temperature and strain level on stress relaxation behaviors of polypropylene sutures. J. Mater. Sci. Mater. Med. 2006, 17, 365–369.
- Liu Z., Yeung K.: The preconditioning and stress relaxation of skin tissue. J. Biomed. Pharm. Engineer. 2008, 2:1, 22–28.
- Liber-Kneć A., Łagan S.: Testing stress relaxation process of a porcine skin. Engineer. Biomater. 2016, 134 (1), 18–24.