# Effect of Diameter and Type of Suture on Knot and Loop Security

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## Abstract

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## 1. Introduction

## 2. Materials and Methods

#### 2.1. Terminology of Knots

**H**’ is used for half-knots and an ‘

**S**’ for half-hitches, followed by the number of throws and the rotation of the active end in comparison with the previous one (‘

**s**’ for symmetric knot resulting from alternate rotation and ‘

**a**’ for asymmetric after similar rotation). In addition, for half-hitches, a sliding sequence is indicated with ‘

**s**’ and blocking with ‘

**b**’. This terminology can be simplified by omitting the number of throws if 1 and the

**s**of sliding to avoid confusion with symmetric. It is important for surgeons to realise that changing the active and passive ends, as occurs with bimanual suturing or when transforming a sliding in a blocking half-hitch, has the same effect as changing rotation. Thus, SSsSsbSab means a second symmetrical and sliding half-hitch (made by alternate rotation). The third half-hitch is also made by alternate rotation (and is therefore called symmetric), resulting in an asymmetric blocking half-hitch of lower quality after changing the active and passive ends. The third half-hitch was made by similar rotation (and is therefore called asymmetric), resulting in a symmetric blocking and stronger half-hitch after changing the active and passive ends.

#### 2.2. Aim of the Study, Knot Combinations, and Power Estimations

#### 2.3. Knot Tying and Testing

#### 2.4. Statistics

## 3. Results

## 4. Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 1.**Symmetric (HHs) and asymmetric (HHa) half-knots are easily changed into half-hitches (SSs and SSa, respectively). Symmetric half-hitches (SSs or SSsSs) remain in one plane, with both ends on one side squeezing the passive end symmetrically and firmly. When the active and passive ends are changed for a blocking half-hitch, the asymmetric half-hitch becomes symmetric on the new passive end (SSsSab).

**Figure 2.**Loop security of polyfilament (Vicryl 2.0) and monofilament (Monocryl 1) sutures. Mean and SDs are indicated.

**Figure 3.**Knot security of Vicryl. Open circles indicate knots that break and closed circles indicate knots that slide open. Mean, SEM, and p-values for the correlation of knot security with suture diameter are indicated.

**Figure 4.**Knot security of Mersilene. Open circles indicate knots that break and closed circles indicate knots that slide open. Mean, SEM, and p-values for the correlation of knot security with suture diameter are indicated.

**Figure 5.**Knot security of PDS. Open circles indicate knots that break and closed circles indicate knots that slide to open. Mean, SEM, and p-values for the correlation of knot security with suture diameter are indicated.

**Figure 6.**Knot security of Monocryl. Open circles indicate knots that break and closed circles indicate knots that slide open. Mean, SEM, and p-values for the correlation of knot security with suture diameter are indicated.

**Figure 7.**Knot security of Monocryl 1 for 5-throw knots composed of 3 sliding + 2 blocking, 2 sliding + 3 blocking, 2-throw + 3 blocking half-hitches, and an asymmetrical square knot + 3 blocking half-hitches.

**Table 1.**Terminology of knot sequences. Following the H for half-knots or the S for half-hitches, the number of throws is indicated. Next, the result of the rotation in comparison with the previous knot is given. A similar rotation results in an asymmetric knot (a) and an opposite rotation in a symmetric knot (s), as shown in Figure 1. H1H1s is thus a flat square knot and H1H1a a granny knot. With polyfilament sutures, secure half-knot sequences are the surgical knot (H2H1sH1s) and 2 or 3-throw half-knots followed by a 2-throw half-knot, irrespective of rotation. The number of throws is omitted for half-hitches because it is always 1, but the sequence blocking (b) after changing the active and passive ends is indicated. A sliding (s) sequence is not indicated to avoid confusion with the s of symmetric. However, changing the active and passive ends has the same effect as changing rotation, and an asymmetric half-hitch becomes symmetric on the new passive end. Knot sequences used to be indicated with = for symmetric (also called identical), x for asymmetric, and // for blocking. We prefer a more intuitive indication emphasising rotation because this is what the surgeon performs when making knots, and sliding is not indicated to avoid confusion with the s indicating symmetric. A 2-throw half-hitch results from the transformation of a 2-throw half-knot.

Knots | Throws | Knot Sequences | Rotation | Old Terminology | New Terminology |
---|---|---|---|---|---|

Half-knot | 1, 2, 3 | H1, H2, H3 | |||

2nd symmetric | alternate | H=H, 1=1 | H1H1s, H2H1s, H2H2s, H3H2s | ||

2nd asymmetric | similar | HxH, 1x1 | H1H1a, H2H1a, H2H2a, H3H2a | ||

Secure polyfilament half-knot sequences: H2H1sH1s, H2H2s or H2H2a, H3H2s or H3H2a | |||||

Half-hitch | 1, 2 | S(1), (S2) | |||

2nd symmetric | alternate | ||||

sliding | S=S, 1=1 | SSs(s) | |||

blocking | S//S | SSsb | |||

2nd asymmetric | similar | ||||

sliding | SxS, 1x1 | SSa(s) | |||

blocking | S//xS | SSab | |||

Secure polyfilament half-hitch sequences: SSsSabSab |

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## Share and Cite

**MDPI and ACS Style**

Romeo, A.; Fujimoto, C.; Cipullo, I.; Giarola, M.; Benedetto, C.; Kondo, W.; Amro, B.; Ussia, A.; Wattiez, A.; Koninckx, P.R.
Effect of Diameter and Type of Suture on Knot and Loop Security. *J. Clin. Med.* **2023**, *12*, 6418.
https://doi.org/10.3390/jcm12196418

**AMA Style**

Romeo A, Fujimoto C, Cipullo I, Giarola M, Benedetto C, Kondo W, Amro B, Ussia A, Wattiez A, Koninckx PR.
Effect of Diameter and Type of Suture on Knot and Loop Security. *Journal of Clinical Medicine*. 2023; 12(19):6418.
https://doi.org/10.3390/jcm12196418

**Chicago/Turabian Style**

Romeo, Armando, Christiane Fujimoto, Isabella Cipullo, Mauricio Giarola, Chiara Benedetto, William Kondo, Bedayah Amro, Anastasia Ussia, Arnaud Wattiez, and Philippe R. Koninckx.
2023. "Effect of Diameter and Type of Suture on Knot and Loop Security" *Journal of Clinical Medicine* 12, no. 19: 6418.
https://doi.org/10.3390/jcm12196418