In vitro evaluation of the knot-holding capacity and security, weight, and volume of forwarder knots tied with size-3 polyglactin 910 suture exposed to air, balanced electrolyte solution, or equine abdominal fat

In vitro evaluation of the effect of tris-EDTA and 0.0005% chlorhexidine solution on the strength of two absorbable sutures

OBJECTIVE

To determine the effect of 0.0005% chlorhexidine and tris-EDTA solution on the strength of three commonly used suture types for closure of equine ventral midline celiotomy.

STUDY DESIGN

Controlled laboratory study.

SAMPLE POPULATION

Knotted loops (n = 10/group, 150 knot constructs total).

METHODS

Strands of 2 polyglactin 910, 3 polyglactin 910, and 2 polydioxanone were tied to form knotted loops. All knotted loops were mounted on a tabletop force measurement machine system and loaded at 100 mm/min until the breaking force (N) was determined. The breaking force (N) of knotted loops using dry suture was recorded at study start, then of knotted loops soaked in either 0.0005% chlorhexidine and tris-EDTA for 20 min followed by incubation in equine serum (treatment) or serum alone (control) for 14 and 21 days. Analysis of variance (ANOVA) compared the breaking force between the treatment and control groups at each time point.

RESULTS

There was no significant difference in the breaking force of 2 USP polyglactin 910 (p = .35, confidence interval [CI] = -0.21-0.59), 3 USP polyglactin 910 (p = .61, CI = -0.41-0.24), or 2 USP polydioxanone (p = .76, CI = -0.63-0.46) soaked in 0.0005% chlorhexidine and tris-EDTA solution followed by equine serum when compared to each respective suture soaked in equine serum only.

CONCLUSION/CLINICAL SIGNIFICANCE

Since 0.0005% chlorhexidine and tris-EDTA solution did not exhibit a significant effect on the breaking force of the absorbable sutures studied, the solution may be used for incisional lavage in the clinical setting.

Knot holding capacity of two different high-strength sutures-a biomechanical analysis

PURPOSE

The number of seven required throws per knot was previously reported as providing sufficient security against slippage. A novel high-strength suture featuring dynamic tightening may allow for throw number reduction without compromising stability. The aims of this study were to (1) investigate the influence of the throw number and the effect of different ambient conditions on the knot security of two different high-strength sutures, and (2) compare their biomechanical competence.

METHODS

Two sutures (FiberWire (FW) and DynaCord (DC)) were considered for preparing alternating surgical knots. The specimens were stratified for exposure to different media during biomechanical testing-namely air (dry), saline solution (wet), and fat (fatty-wet). A monotonic tensile ramp loading to failure was applied in each test run. For each suture and ambient condition, seven specimens with three to seven throws each were tested (n = 7), evaluating their slippage and ultimate force to failure. The minimum number of throws preventing suture unraveling was determined for each suture type and condition.

RESULTS

For each suture type and condition, failure occurred via rupture in all specimens for the following minimum number of throws: FW-dry-7, wet-7, fatty-wet-7; DC-dry-6, wet-4, fatty-wet-5. When applying seven throws, FW demonstrated significantly larger slippage (6.5 ± 2.2 mm) versus DC (3.5 ± 0.4 mm) in wet (p = 0.004) but not in dry and fatty-wet conditions (p ≥ 0.313).

CONCLUSIONS

The lower number of throws providing knot security of DC versus FW in the more realistic wet and fatty-wet conditions indicates that the novel DC suture may allow to decrease the foreign body volume and save surgical time without compromising the biomechanical competence.

Fascia Repair with Vicryl Suture in Urologic Surgeries

Background: Closing the fascia after surgery should be quick, easy, and strong but comfortable for the patient. Polydioxanone thread is not available in Iran. Thus, we used Vicryl sutures for almost all patients. Methods: This study was conducted at Imam Reza and Imam Khomeini Medical Centers in Ardabil from January 2018 to January 2020. The fascia was continuously sutured with size 0 or 1 of Vicryl in a double layer for all patients in the Urology Department. Results: Here, 642 patients were evaluated in two years. The fascia suturing was at the site of the inguinal, midline Gibson, and flank areas. The data showed that incisional hernia and infection were more prevalent in obese and diabetic patients. We had no incisional complications in radical cystectomy or even kidney transplantation, which are complicated and time-consuming surgeries. Overall, the surgical site complication rate (including incisional hernia and surgical site infection) was 0.9%, which could be negligible. Conclusions: The fascia repair could be treated with Vicryl suture in a continuous form in all urologic surgeries, with a very low rate of wound infection and hernia at the operation site, sinus formation, and long-term surgical site discomfort. However, we suggest more research to confirm the Vicryl suture safety in urologic fascia repairs.

Tensile strength and early healing of self-locking and surgeon's knots

OBJECTIVE

To compare the biomechanical properties and healing of ventral midline celiotomies (VMC) closed with a self-locking knot combination and forwarder start and Aberdeen end (F-A) vs a traditional knot combination and surgeon's start and end (S-S).

STUDY DESIGN

In vivo, experimental.

ANIMALS

Twenty-one horses.

METHODS

Fourteen horses underwent VMC, which was closed with either an F-A (n = 7) or an S-S (n = 7) knot combination. Incisions were subjectively graded by masked evaluators for dehiscence, edema, and drainage. Biomechanical testing was performed on three abdominal segments, and histology was performed on one segment from each animal after humane euthanasia 10 days post-VMC. The abdominal wall of control horses (n = 7, no celiotomy) was collected for biomechanical testing.

RESULTS

Forwarder start and Aberdeen end and S-S horses had less tensile strength compared with control horses (P ≤ .001). No differences were detected between treatment groups for any variable evaluated, including tensile strength (P = .975), location of failure (P = .240), and histologic healing at the knot (P = .600).

CONCLUSION

Closure of VMC with self-locking knots resulted in biomechanical and healing features similar to those with a traditional closure technique, with neither restoring the tensile strength of the linea alba.

CLINICAL SIGNIFICANCE

Results of this study provide evidence to support a clinical trial to evaluate long-term performance of the F-A self-locking knot closure in horses.