Abstract
Background:
Surgical knot security is essential to preventing complications such as knot failure or tissue tearing. The number of throws and the use of surgeon’s knots influence knot strength; thus, this study aimed to evaluate the impact of throws and surgeon’s knots on the tensile strength and loop elongation of Vicryl and Prolene 5-0 sutures.
Methods:
Vicryl and Prolene 5-0 sutures were tied in knots of 3, 4, and 5 throws, across 12 different knot sequences: single knots only, surgeon’s knots only, and an increasing number of surgeon’s knots. Samples were tested using a tensiometer applying a constant force until knot failure or slippage.
Results:
The tensile strength of the knots increased significantly with the number of throws and the presence of surgeon’s knots (P < 0.005). Five-throw knots were stronger than 3-throw knots regardless of the number of surgeon’s knots for both types of sutures. The use of surgeon’s knots only significantly increased strength in the 3-throw series for both Prolene and Vicryl sutures. For both sutures, a 3-throw surgeon’s knot showed the same tensile strength as a 5-throw simple knot. Loop elongation depended on the number of throws and surgeon’s knots.
Conclusions:
The use of surgeon’s knots alone increased a knot’s breaking resistance without the need for additional simple throws. A 3-throw surgeon’s knot provides breaking resistance equivalent to a knot with more throws. If reduced loop elongation is desired, the choices would be 4 surgeon’s throws for Vicryl and 5 simple throws for Prolene.
Takeaways
Question: This study evaluated how throw number and the use of surgeon’s knots affect tensile strength and loop elongation in Vicryl and Prolene 5-0 sutures to improve knot security and reduce complications.
Findings: Increasing the throws and using surgeon’s knots significantly increased tensile strength. A 3-throw surgeon’s knot matched the strength of a 5-throw simple knot.
Meaning: Three surgeon’s throws offer similar strength to higher throw knots but are more susceptible to elongation. To minimize elongation, 4-throw surgeon’s knots are recommended for Vicryl and 5-throw simple knots for Prolene.
INTRODUCTION
The security and tensile strength of knots are key elements for successful surgical procedures, particularly because the knot is the weakest point of the suture.1 It has been shown that the efficacy of knots used in surgical practice varies depending on the institutions and training.2 Studies have examined the strength and security of knots based on several factors: material, number of throws, size, and the use of an initial surgeon’s knot. Some studies have shown that the suture material and the number of throws play a key role in knot tensile strength, unlike the placement of a surgeon’s knot as the first knot and the size of the sutures, which do not affect knot security.3–7 In cleft palate surgery, the formation of oronasal fistulas is a complication of wound dehiscence,8,9 which can result from knot rupture, slippage, or tissue tearing. United States Pharmacopeia (USP) size 5-0 sutures have been specifically investigated in oral surgery procedures. In an in vitro experimental study using animal oral mucosa samples, size 3-0 was found to consistently tear tissues, and size 7-0 to break due to its excessive fragility. Only size 5-0 exhibited both behaviors, tearing tissues because of its resistance and occasionally breaking in an unpredictable fashion.10 To our knowledge, however, there has been no study investigating the effect of multiple consecutive surgeon’s knots on tensile strength.
The aim of this study was to determine whether the use of multiple throws of surgeon’s knots or simple knots increased knot tensile strength and altered suture loop elongation. The null hypothesis was that the addition of throws and surgeon’s knots did not change tensile strength or loop elongation. The study focused on 2 sutures, Vicryl and Prolene USP 5-0, which are commonly used in oral and cleft palate repair surgery.
MATERIALS AND METHODS
Sutures Knotting
Two USP 5-0 suture materials were tested in this study: polyglactin 910 (Vicryl, Ethicon, Johnson & Johnson, Somerville, NJ) and polypropylene (Prolene, Ethicon, Johnson & Johnson, Somerville, NJ), using sutures from the same batch whenever possible. Twelve sets of 12 samples were knotted per suture type, using knot configurations of 3, 4, and 5 throws, as 2-throw knots were previously demonstrated to be unstable.4 For each suture type, several series of knots were tied: a series of 3 simple overhand square knots (1 = 1 = 1) (3S), a series of 3 double overhand (surgeon’s) square knots (2 = 2 = 2) (3C).1 And other combinations involving multiple throws of surgeon’s knots, alone or combined with simple knots, were tested. The knot designs are shown in Figures 1–3. The nonsquare “granny” knot was not tested, as it has lower tensile strength for an equal number of throws11 (Table 1).
Fig. 1.
Knot types. Simple knot (A), surgeon’s knot (B), first sliding throw (C), and sliding knot (D). A is a simple flat knot and B is a double flat knot. C and D represent sliding knots (not used in this study).
Fig. 3.
Knots composed solely of surgeon’s throws. Type 3C (A), 4C (B), and 5C (C).
Table 1.
Types of Knots
| No. Throws | Type of Knot | Abbreviation |
|---|---|---|
| 3 | 1 = 1 = 1 | 3S |
| 2 = 1 = 1 | 1C2S | |
| 2 = 2 = 1 | 2C1S | |
| 2 = 2 = 2 | 3C | |
| 4 | 1 = 1 = 1 = 1 | 4S |
| 2 = 1 = 1 = 1 | 1C3S | |
| 2 = 2 = 1 = 1 | 2C2S | |
| 2 = 2 = 2 = 1 | 3C1S | |
| 2 = 2 = 2 = 2 | 4C | |
| 5 | 1 = 1 = 1 = 1 = 1 2 = 1 = 1 = 1 = 1 |
5S 1C4S |
| 2 = 2 = 2 = 2 = 2 | 5C |
Number 1 represents a simple knot, number 2 represents a surgical knot, and the “=” symbol indicates that the knot is flat and nonsliding.12
Fig. 2.
Series of simple knots and surgeon’s knots. Configuration of a simple knot of type 3S (A), 4S (B), and 5S (C). Knot with the first throw doubled, followed by simple knots: type 1C2S (D), 1C3S (E), and 1C4S (F).
For this study, to replicate the conditions under which knots are tied, we custom-crafted a stainless steel base with 2 spacing pins equal in size to those of the tensiometer and used it for tying the knots. The pins were surrounded by a silicone sheath to protect the knot loop from friction. The knots were tied by a single trained operator using a standardized technique over several days to avoid biases due to fatigue, ensuring equal tension on both ends of the suture to lay the knot flat and square. Standard surgeon’s instruments were used to tie the knots, as it was demonstrated that the use of instruments in knot tying did not alter the suture’s tensile strength.13 The outer distance between the 2 pins was 8 mm, and the size of the loop was approximately equal to 42 mm. We kept the loop length as short as possible to mimic the clinical setting and also because data from the literature indicates that loop size impacts knot strength and loop elongation14 (Figs 4 and 5).
Fig. 4.
Custom-created support for knot preparation before testing.
Fig. 5.
Tensiometer setup.
Mechanical Testing
The tensile strength and elongation of the sutures were measured using a tensiometer (1-kN zwickiLine with Xforce HP 1-kN force sensor, ZwickRoell GmbH & Co. KG, Ulm, Germany). The distance between the centers of the 2 pins of the tensiometer was 5 mm. The tensiometer was precalibrated 5 times with knots made from the same suture material as the one being tested. The loops were placed over the pins using clamps, grasping only the free ends of the sutures to avoid damaging the loop. The grip-to-grip distance was set to 5 mm (Fig. 5) to allow the operator to insert the prepared loop. Initially, the sensor measured 0 N, as the loop was not yet under tension. The machine operated in preload mode, applying a speed of 20 mm/min until a preload of 0.1 N was reached. Once achieved, data acquisition began, and the test proceeded in force control mode with a force increase rate of 1 N/s until the knot ruptured or slipped. The tensiometer continuously recorded the tension and elongation. An observer checked whether the suture loop broke, and if so, where (near the knot/elsewhere on the loop), or if the knot slipped.
Statistical Analysis
Because the data distribution was nonnormal (Shapiro–Wilk test), comparison between different groups was performed using the Kruskal–Wallis test for multiple group comparisons, followed by the Dunn post hoc test.15 The difference was considered statistically significant at P < 0.05. Results were reported as median and range. Statistical analyses were performed using Prism v.8.4.3 (GraphPad Software, San Diego, CA).
RESULTS
The tensile strength of the knots was compared based on the number of throws and the number of simple or surgeon’s knots, and the results are presented in Table 2. The elongation of the sutures is reported in Table 3 (Figs. 6 and 7).
Table 2.
Tensile Strength in Newtons at Knot Rupture (All USP 5-0)
| Vicryl | Prolene | ||||
|---|---|---|---|---|---|
| Throws, n | Knot Type | Median | Range | Median | Range |
| 3 | 3S | 8.675 | 4.78–14.10 | 13.750 | 11.10–14.90 |
| 1C2S | 11.550 | 9.49–21.10 | 15.100 | 12.20–16.00 | |
| 2C1S | 18.450 | 13.40–20.40 | 15.050 | 12.90–17.60 | |
| 3C | 18.700 | 15.10–21.90 | 16.800 | 14.30–19.10 | |
| 4 | 4S | 17.850 | 10.90–23.80 | 15.200 | 14.20–16.30 |
| 1C3S | 17.250 | 2.50–22.80 | 15.550 | 13.60–16.40 | |
| 2C2S | 19.800 | 14.80–23.10 | 17.200 | 14.50–17.60 | |
| 3C1S | 20.100 | 17.10–22.10 | 16.300 | 15.00–18.20 | |
| 4C | 19.750 | 10.10–24.00 | 16.200 | 14.60–17.90 | |
| 5 | 5S | 19.300 | 17.80–22.50 | 15.450 | 14.00–16.80 |
| 1C4S | 20.050 | 18.60–21.40 | 16.050 | 14.50–18.00 | |
| 5C | 20.450 | 18.30–23.00 | 17.350 | 15.10–18.30 | |
Table 3.
Maximum Loop Elongation (in mm) Before Rupture (All USP 5-0)
| Vicryl | Prolene | ||||
|---|---|---|---|---|---|
| Throw, n | Knot Type | Median | Range | Median | Range |
| 3 | 3S | 4.500 | 2.80–5.90 | 4.650 | 3.60–5.30 |
| 1C2S | 4.400 | 3.70–8.30 | 5.650 | 4.20–6.80 | |
| 2C1S | 4.450 | 3.80–5.10 | 5.900 | 4.10–7.10 | |
| 3C | 4.050 | 3.30–4.90 | 6.100 | 5.10–9.70 | |
| 4 | 4S | 4.750 | 4.50–6.20 | 4.700 | 4.00–5.50 |
| 1C3S | 3.950 | 3.30–6.20 | 5.850 | 4.80–7.40 | |
| 2C2S | 4.050 | 3.40–4.80 | 6.100 | 4.40–6.80 | |
| 3C1S | 3.850 | 3.10–5.40 | 5.750 | 5.00–6.20 | |
| 4C | 3.550 | 2.70–7.00 | 4.900 | 4.30–8.30 | |
| 5 | 5S | 3.850 | 3.20–5.50 | 4.250 | 3.90–4.70 |
| 1C4S | 4.050 | 3.40–5.20 | 4.500 | 3.60–5.90 | |
| 5C | 3.650 | 3.10–4.30 | 5.400 | 4.50–7.10 | |
Fig. 6.
Maximum breaking strength for Vicryl USP 5-0. N, Newton.
Fig. 7.
Maximum breaking strength for Prolene USP 5-0. N, Newton.
Number of Throws
The number of throws increased tensile strength independently of the number of surgeon’s knots. Five-throw surgeon’s knots (5C) showed the highest tensile strength (20.5 N for Vicryl and 17.35 N for Prolene), whereas the lowest was observed in 3-throw simple knots (3S) (8.68 N for Vicryl and 13.75 N for Prolene). For both sutures, 5-throw knots were stronger than 3-throw knots (P < 0.0001), and 4-throw knots were stronger than 3-throw knots for Vicryl (P < 0.0001) and Prolene (P = 0.004). For Vicryl, a statistically significant difference was also found between 5-throw and 4-throw knots (P = 0.035), unlike for Prolene. A wider data distribution range was noted for 3-throw knots compared with 4 or 5 throws. For both sutures, 5-throw knots showed the least data dispersion.
Number of Surgeon’s Knots
The number of surgeon’s knots increased knot tensile strength with fewer throws. For both sutures, a statistically significant difference in textile strength was found between type 3S and 3C knots: Vicryl, 8.68 versus 18.7 N (P = 0.0022); Prolene, 13.75 versus 16.8 N (P = 0.0001).
Regarding Vicryl, the 3S knots mostly slipped (10 of 12), which was not the case for other knots with 3 throws combining surgeon’s and simple knots. The data from Vicryl 3S knots were still included in the study despite slipping, as they represent what would happen clinically if these knots were used. Prolene 3S knots did not slip.
The use of surgeon’s knots significantly increases tensile strength only in 3-throw knots. From 4 throws onward, the type of knot used does not change the strength of Vicryl knots, whereas for Prolene, the 5C knot (17.35 N) is stronger compared with 4-throw 4S knots (15.2 N, P = 0.014) and 1C3S knots (15.55 N, P = 0.0185).
Loop Elongation
The comparison of suture loop elongation with different numbers of throws showed a statistically significant difference between 3-throw and 5-throw knots (P = 0.001) for both types of sutures: Vicryl, 3 throws 4.4 mm versus 5 throws 3.8 mm, and Prolene, 3 throws 5.6 mm versus 5 throws 4.5 mm.
For Vicryl, the maximum elongation was in the 4S series (4.75 mm). It was significantly longer than 4C (3.55 mm, P = 0.0002), the least extensible knot. For Vicryl, knots with surgeon’s knots throw had a loop that stretched less than with simple knots.
For Prolene, a difference was also found between 4-throw and 5-throw knots (P = 0.001). The use of surgeon’s knots had an impact on loop elongation for knots with the same number of throws; a difference was found between 5S (4.25 mm) and 5C (5.4 mm) (P = 0.004). The loop with the greatest elongation was of type 3C (6.1 mm), and the least elongated was of type 4S (4.25 mm) (Figs. 8 and 9).
Fig. 8.
Maximum elongation (in mm) at break for Vicryl USP 5-0.
Fig. 9.
Maximum elongation (in mm) at break for Prolene USP 5-0.
DISCUSSION
Determining the optimal knot for a specific type of surgeon’s suture requires identifying the number of throws and the type of knot (surgeon’s versus simple) required to obtain a strong knot. This study focused on the impact of using surgeon’s knots and increasing the number of throws on knot strength and loop elongation.
Our study shows that the use of surgeon’s knots and the addition of throws increase the tensile strength of both sutures. The elongation of the loop is not always proportional to the number of surgeon’s knots and throws, although it is difficult to determine the consequences of such elongation in a clinical context, given the behavior of biological tissues and their own resistance to the shearing force of the suture. This study demonstrates that the number of throws and the presence of 1 or more surgeon’s knots increase tensile strength and modify loop elongation, rejecting the null hypothesis.
Vicryl Tensile Strength
The tensile strength of Vicryl knots is related to the number of throws and the number of surgeon’s knots, particularly for knots with few throws. Tensile strength increased in a statistically significant way as the number of throws increased.
In this study, for the analysis of 3-throw knots, it was necessary to differentiate between Vicryl 3S knots, which slipped for the most part, indicating poor knot security, and other 3-throw knots including surgeon’s knots, which held. For the 3-throw Vicryl knots, the use of surgeon’s knots (1C2S and 2C1S) increased the tensile strength (11.55 and 18.45 N, respectively) and reduced the distribution range of the data.
Although one study reported the strength of Vicryl knots with 3 throws of single knots,4 several other studies indicate that 4 throws are needed for the knot to be secure,2,6,16,17 which confirms our findings. The use of surgeon’s knots made it possible to prevent slipping knots and considerably increase their tensile strength. The use of a first throw with a surgeon’s knot could make 3 throws sufficient. Type 3C knots showed no statistically significant difference from knots with more throws, with a breaking strength of 18.7 N (distribution interval: 15.10–21.90 N), which is slightly lower than that of 4- and 5-throw knots with surgeon’s knots, but higher than that of 4S (17.85 N) and close to that of 5S (19.3 N, distribution interval 17.80–22.50 N).
This would suggest that it is possible to spare 2 throws of knots by tying 3 surgeon’s knots. This could be of interest, especially in cleft palate or intraoral surgery, as the suture is passed around the needle holder outside of the mouth; adding a second loop around the instrument is less time-consuming than adding supplementary throws. In the literature, it has been shown that starting with a surgeon’s knot and continuing with simple ones made no statistically significant difference in tensile strength.3 Our statistical data also confirm this observation. On the other hand, the use of several surgeon’s knots provides greater tensile strength to the knot. The use of 1C4S-type knots may be of interest in cases where a higher tensile strength is required, although 3C-type knots appear to have sufficient tensile strength, making it possible to use 2 fewer throws.
Prolene Tensile Strength
For Prolene, regarding the differences in tensile strength between the sets of knots, 3C (median 16.8 N) and 2C2S (17.2 N) are of interest. We did not identify any statistically significant difference between the 3C and the series with more throws. However, 3C has a wider spread of data than knots with 4 or more throws. The 2C2S knot revealed no statistically significant difference compared with knots with more throws or with surgeon’s-type throws, and showed a reduced spread of results. The 2C2S knot could be an alternative to 3C if consistent tensile strength is desired.
In the case of Prolene, a synergy between the addition of throws and the use of surgeon’s knots was noted. We found no statistically significant difference between 4 and 5 throws of single knots, in line with what has been found in the literature16; however, the 4S series has a statistically significantly lower tensile strength compared with the 5C series (P = 0.014) (Tables 2 and 3).
Loop Elongation
In terms of loop elongation, for Vicryl, knots with more surgeon’s knots had less loop elongation than their single counterparts, for example, 4C 3.55 versus 4S 4.75 mm (P = 0.004). Five-throw knots also had less loop elongation than 3-throw knots (P = 0.001).
For Prolene, the loops stretched less with single knots (3S 4.65 versus 3C 6.1 mm [P = 0.0006] and 5S 4.25 versus 5C 5.4 mm [P = 0.004]), and the 5-throw knots had statistically significantly less elongation than the 3- and 4-throw knots. The knot with the greatest loop stretch was 3C.
Considering the small differences in elongation, it is difficult to draw any conclusions about the potential clinical consequences of these results.
For both Prolene and Vicryl, 3 surgeon’s knots seem sufficient to ensure good tensile strength. However, although surgeon’s knots increase strength, they have been reported to reduce the adaptability of the suture to the wound.12 This is due to the closed configuration of the surgeon’s knot, which prevents the temporary transformation of the single knot into a sliding knot, potentially providing better coaptation of the wound edges. For Prolene, the loop elongation is maximal with 3C and lowest with 5S. However, it has been reported in the literature that single knots have a tendency to become sliding knots in clinical practice,3 which may allow knot tension to adapt, but considerably reduces tensile strength.11,12 The use of more throws and surgeon’s knots provides the safest configuration; however, increasing the volume of the knot may potentially cause more foreign body reaction and inflammation for buried knots, especially with absorbable sutures.18,19 In a future study, we would like to determine the maximum tension that the tissues can withstand without shearing, to identify the optimum knot, taking this factor into account.
LIMITATIONS
This study was conducted under experimental conditions, in a dry environment, without manipulation and/or pinching of the sutures by instruments, and without the stress of the surgical procedure, which could influence the tension applied to the suture ends20 and, therefore, the configuration of the knots, all factors that could produce different results to those reported here.
CONCLUSIONS
In this study, for both Prolene and Vicryl USP 5-0, knots with 3 surgeon’s throws (3C) had equivalent tensile strength to knots with more throws. However, this knot configuration is more prone to elongation, and for a suture where this is not desirable, 4C knots should be used for Vicryl and 5S knots for Prolene (Tables 4–7).
Table 4.
Comparison of Differences in the Breaking Strength of Various Vicryl USP 5-0 Knots
| Knots | 3S | 1C2S | 2C1S | 3C | 4S | 1C3S | 2C2S | 4C | 3C1S | 5S | 1C4S | 5C |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3S | x | NS | NS | P = 0.0022 | NS | NS | P = 0.0001 | P = 0.0001 | P < 0.0001 | P = 0.0006 | P < 0.0001 | P < 0.0001 |
| 1C2S | NS | x | NS | NS | NS | NS | NS | NS | P = 0.0366 | NS | P = 0.0112 | P = 0.0021 |
| 2C1S | NS | NS | x | NS | NS | NS | NS | NS | NS | NS | NS | NS |
| 3C | P = 0.0022 | NS | NS | x | NS | NS | NS | NS | NS | NS | NS | NS |
| 4S | NS | NS | NS | NS | x | NS | NS | NS | NS | NS | NS | NS |
| 1C3S | NS | NS | NS | NS | NS | x | NS | NS | NS | NS | NS | NS |
| 2C2S | P = 0.0001 | NS | NS | NS | NS | NS | x | NS | NS | NS | NS | NS |
| 4C | P = 0.0001 | NS | NS | NS | NS | NS | NS | x | NS | NS | NS | NS |
| 3C1S | P < 0.0001 | P = 0.0366 | NS | NS | NS | NS | NS | NS | x | NS | NS | NS |
| 5S | P = 0.0006 | NS | NS | NS | NS | NS | NS | NS | NS | x | NS | NS |
| 1C4S | P < 0.0001 | P = 0.0112 | NS | NS | NS | NS | NS | NS | NS | NS | x | NS |
| 5C | P < 0.0001 | P = 0.0021 | NS | NS | NS | NS | NS | NS | NS | NS | NS | x |
Multiple comparisons between the different series were performed using the Kruskal–Wallis test with the Dunn post hoc correction.
NS, non significant; x, non applicable.
Table 7.
Statistical Differences in Loop Elongation for Prolene USP 5-0
| Knots | 3S | 1C2S | 2C1S | 3C | 4S | 1C3S | 2C2S | 4C | 3C1S | 5S | 1C4S | 5C |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3S | x | NS | P = 0.0157 | P = 0.0006 | NS | P = 0.0148 | P = 0.0108 | NS | P = 0.0402 | NS | NS | NS |
| 1C2S | NS | x | NS | NS | NS | NS | NS | NS | NS | P = 0.0093 | NS | NS |
| 2C1S | P = 0.0157 | NS | x | NS | NS | NS | NS | NS | NS | P = 0.003 | P = 0.0456 | NS |
| 3C | P = 0.0006 | NS | NS | x | NS | NS | NS | NS | NS | P < 0.0001 | P = 0.0022 | NS |
| 4S | NS | NS | NS | NS | x | NS | NS | NS | NS | NS | NS | NS |
| 1C3S | P = 0.0148 | NS | NS | NS | NS | x | NS | NS | NS | P = 0.0003 | P = 0.0432 | NS |
| 2C2S | P = 0.0108 | NS | NS | NS | NS | NS | x | NS | NS | P = 0.0002 | P = 0.032 | NS |
| 4C | NS | NS | NS | NS | NS | NS | NS | NS | x | NS | NS | NS |
| 3C1S | P = 0.0402 | NS | NS | NS | NS | NS | NS | x | NS | P = 0.001 | NS | NS |
| 5S | NS | P = 0.0093 | P = 0.003 | P < 0.0001 | NS | P = 0.0003 | P = 0.0002 | NS | P = 0.001 | x | NS | P = 0.004 |
| 1C4S | NS | NS | P = 0.0456 | P = 0.0022 | NS | P = 0.0432 | P = 0.032 | NS | NS | NS | x | NS |
| 5C | NS | NS | NS | NS | NS | NS | NS | NS | NS | P = 0.001 | NS | x |
Multiple comparisons between the different series were performed using the Kruskal–Wallis test with the Dunn post hoc correction.
NS, non significant; x, non applicable.
Table 5.
Comparison of Differences in the Breaking Strength of Various Prolene USP 5-0 Knots
| Knotes | 3S | 1C2S | 2C1S | 3C | 4S | 1C3S | 2C2S | 4C | 3C1S | 5S | 1C4S | 5C |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3S | x | NS | NS | P = 0.0001 | NS | NS | P < 0.0001 | P = 0.0052 | P = 0.0003 | NS | P = 0.0015 | P < 0.0001 |
| 1C2S | NS | x | NS | NS | NS | NS | P = 0.0099 | NS | NS | NS | NS | P = 0.0015 |
| 2C1S | NS | NS | x | NS | NS | NS | NS | NS | NS | NS | NS | NS |
| 3C | P = 0.0001 | NS | NS | x | NS | NS | NS | NS | NS | NS | NS | NS |
| 4S | NS | NS | NS | NS | x | NS | NS | NS | NS | NS | NS | P = 0.014 |
| 1C3S | NS | NS | NS | NS | NS | x | NS | NS | NS | NS | NS | P = 0.0185 |
| 2C2S | P < 0.0001 | P = 0.0099 | NS | NS | NS | NS | x | NS | NS | NS | NS | NS |
| 4C | P = 0.0052 | NS | NS | NS | NS | NS | NS | x | NS | NS | NS | NS |
| 3C1S | P = 0.0003 | NS | NS | NS | NS | NS | NS | NS | x | NS | NS | NS |
| 5S | NS | NS | NS | NS | NS | NS | NS | NS | NS | x | NS | NS |
| 1C4S | P = 0.0015 | NS | NS | NS | NS | NS | NS | NS | NS | NS | x | NS |
| 5C | P < 0.0001 | P = 0.0015 | NS | NS | P = 0.014 | P = 0.0185 | NS | NS | NS | NS | NS | x |
Multiple comparisons between the different series were performed using the Kruskal–Wallis test with the Dunn post hoc correction.
NS, non significant; x, non applicable.
Table 6.
Statistical Difference in the Maximum Elongation of Loops (mm) Before Breaking for Vicryl USP 5-0
| Knots | 3S | 1C2S | 2C1S | 3C | 4S | 1C3S | 2C2S | 4C | 3C1S | 5S | 1C4S | 5C |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3S | x | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
| 1C2S | NS | x | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
| 2C1S | NS | NS | x | NS | NS | NS | NS | NS | NS | NS | NS | P = 0.0342 |
| 3C | NS | NS | NS | x | NS | NS | NS | NS | NS | NS | NS | NS |
| 4S | NS | NS | NS | NS | x | NS | NS | P = 0.0004 | NS | NS | NS | P = 0.0002 |
| 1C3S | NS | NS | NS | NS | NS | x | NS | NS | NS | NS | NS | NS |
| 2C2S | NS | NS | NS | NS | NS | NS | x | NS | NS | NS | NS | NS |
| 4C | NS | NS | NS | NS | P = 0.0004 | NS | NS | x | NS | NS | NS | NS |
| 3C1S | NS | NS | NS | NS | NS | NS | NS | NS | x | NS | NS | NS |
| 5S | NS | NS | NS | NS | NS | NS | NS | NS | NS | x | NS | NS |
| 1C4S | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | x | NS |
| 5C | NS | NS | P = 0.0342 | NS | P = 0.0002 | NS | NS | NS | NS | NS | NS | x |
Multiple comparisons between the different series were performed using the Kruskal–Wallis test with the Dunn post hoc correction.
NS, non significant; x, non applicable.
DISCLOSURE
The authors have no financial interest to declare in relation to the content of this article.
ACKNOWLEDGMENTS
The authors wish to thank the Wyss Center for Bio and Neuroengineering in Geneva for kindly providing access to the measurement tools. Tensile strength and elongation were measured using a ZwickRoell zwickiLine 1-kN tensiometer (Wyss Center for Bio and Neuroengineering), which was kindly provided without any funding request.
Footnotes
Published online 18 July 2025.
Disclosure statements are at the end of this article, following the correspondence information.
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