Knowing how to tie surgical knots is an essential skill for all surgeons as these knots serve a wide range of purposes during surgeries. A well-tied knot should be firm and secure, but excessive tension can cause harm to both the tissue and the suture, resulting in poor wound healing and tissue necrosis. Additionally, to reduce foreign body reactions, knots should be as small as possible. This set of instructions outlines the steps to create a surgical knot tying using a short thread and a long thread.
This article focuses on the two major techniques for knot tying, namely the single-handed tie and the tie at depth. The square surgeons knot is the most reliable and well-known method for almost all suture materials.
To tie a single-handed knot, start with the short thread facing upwards and the long thread facing downwards. Use the left thumb and ring finger to hold the end of the short thread, while the remainder of the thread passes over the left index and middle fingers. Use the right thumb and index finger to pick up the end of the long thread and bring it up to align with the short thread.
Next, pass the short thread under and then over the long thread using the left middle finger, while still holding the end between the left thumb and ring finger. Pull the right hand upwards and the left hand downwards, allowing the knot to settle in position, and adjust the tension of the knot as necessary.
Then, come back upwards with the short thread by holding the end with the left thumb and index finger. Pick up the long thread with the right thumb and index finger and bring it downwards to align with the short thread. Repeat the previous manoeuvre of passing the short thread under and over the long thread and adjust the tension of the knot as necessary.
Finally, repeat the same manoeuvre as before with the short thread facing upwards and the long thread facing downwards. Adjust the final tension of the knot as necessary. Don’t miss reading these 9 benefits of awareness during surgery you might not know.
Surgical Knot Tying at Depth
The tying at depth technique is utilized for knot tying in deep body cavities. It is critical to tie the knot firmly to prevent it from slipping, while avoiding upward pressure to prevent tearing of the tissue.
To perform the procedure, start with the short thread facing upwards and the long thread facing downwards. Outside the cavity, pick up the end of the short thread with the left thumb and ring finger, with the rest of the thread passing over the left index and middle fingers. Use the right thumb and index finger to pick up the end of the long thread and bring it up to align with the short thread.
Next, pass the short thread under and then over the long thread using the left middle finger, while still holding the end between the left thumb and ring finger. Pull the right hand upwards and the left hand downwards.
While holding tension in the long thread with the right hand outside the cavity, use the left index finger to push the knot down past where it is needed to lie inside the cavity.
Then, come back upwards with the short thread by holding the end with the left thumb and index finger. Pick up the long thread with the right thumb and index finger and bring it downwards to align with the short thread.
Begin by passing the short thread under and over the long thread. This creates the initial loop for the knot.
Next, pull your right hand upwards and your left hand downwards to tighten the loop and form the beginnings of the knot.
While holding tension in the long thread with your right hand outside the cavity (or space where the knot will be placed), use your left index finger to push the knot downwards past where it needs to lie inside the cavity. This ensures that the knot will be situated in the right position once completed.
Repeat step 1 by passing the short thread under and over the long thread again. However, this time the short thread should face upwards while the long thread faces downwards. This creates a second loop to complete the knot.
Finally, adjust the final tension of the knot as necessary by pushing past the knot with your index finger. This step helps to ensure that the knot is securely tied and properly positioned.
Surgical Knot Tying: Two-handed Tie
The two-handed tie is a crucial skill in general surgery. Despite the one-handed tie being faster, the two-handed tie provides better control of knot tension and increases knot security.
The key is to achieve tissue approximation without strangulation by tying the knot tight enough to prevent slipping and bringing tissue together snugly, but not so tight that it causes ischemia and wound breakdown.
Knot-tying practice should start with ropes or strings and progress to larger sutures and eventually smaller ones until the skill becomes automatic. Once automatic, practice should continue while wearing gloves, in narrow cavities, or under increased tension.
It is important to note the differences between square knots and granny knots. Square knots are more secure than granny knots, which are more likely to fail due to slippage or unraveling.
Some surgeons may intentionally use slip knots or granny knots in certain situations, but it should be a deliberate decision based on knot security and tension. When intentionally using a granny knot, adding additional throws to the knot can compensate for increased slippage.
The Surgeon’s Knot
The Surgeon’s Knot is a modified version of the square knot, commonly used in surgical procedures. It is created by bringing the initial throw through the loop twice, instead of just once as in a traditional square knot. This double throw creates greater friction within the knot, which helps to resist the wound from pulling apart while the knot is being tied.
This technique is especially helpful when dealing with wounds that are under tension, as it provides greater security and stability during the healing process.
Many surgeons routinely use the Surgeon’s Knot in most clinical scenarios due to its reliability and effectiveness in securing the wound. The additional throw increases the knot’s strength, making it less likely to come undone during the healing process. This is particularly important when dealing with deep incisions or injuries that require strong support to promote proper healing.
The Surgeon’s Knot is also beneficial because it allows the surgeon to adjust the tension of the wound before tying off the knot completely. This helps to ensure that the tissue is tightly approximated without causing damage or strangulation of the tissue, which can lead to complications such as wound breakdown or infection.
Overall, the Surgeon’s Knot is a useful technique for surgeons to have in their repertoire when performing surgical procedures. Its ability to increase knot security, resist wound pulling, and allow for tension adjustments makes it a valuable tool in promoting successful wound healing.
By following these steps, you should be able to create a well-formed knot using a short thread and a long thread.
