Suture Anchors - Meaning, Conditions, Types, Mechanism, and Characteristics

What Are Suture Anchors?

Suture anchors are biocompatible materials broadly used for attaching soft tissues like ligaments, tendons, and meniscus to the bone. It is most commonly used in sports medicine and arthroscopic surgeries. Suture anchors are also called bone anchors. They are described as surgical implants. These suture or bone anchors may be achieved by knotting one end of the suture tissues and the other to the implant devices that attach the sutures to the bone. Suture anchors are most commonly used in the knee and shoulders for reattaching the tendons and ligaments.

What Are Suture Anchors Made Up Of?

Suture anchors are small implants that come in different designs, sizes, materials, and configurations. The suture anchors are made up of:

• The Suture - Suture is a biodegradable material that is attached to an anchor through an eyelet of the anchor. There may be absorbable suture material and non absorbable suture material. In addition to this, there are various suture materials used in orthopedic surgeries.

• The Eyelet - It is a loop or hole in the anchor which allows the suture to pass. The eyelet is the way that links the anchor to the suture.

• The Anchor - Anchor is the implant material that is inserted into the bone. These anchors may be an interference fit, deployable, bioresorbable, or a screw-in mechanism. These anchors are made of biodegradable material (material that can dissolve into the body over time) or metal.

In addition to this, the materials that are used for suture anchors include titanium, stainless steel, or coated titanium.

What Are the Types of Suture Anchors?

The suture anchors are available in various sizes, configurations, and designs based on their use. Most commonly, the suture anchors come under two types: bio-absorbable and non-absorbable.

1. Bio-Absorbable Sutures - These bio-absorbable suture anchors are generally used in the body's inner tissues. Within ten days to four weeks, these sutures get broken down in the tissues. These sutures are mostly used in wounds that heal fast. So that the foreign materials can not be left inside the body. These bio-absorbable suture anchors are the most preferred fixation devices as it has only fewer post-surgical complications. The bio-absorbable suture anchors are most increasingly used in sports medicines for various procedures.

2. Non-Absorbable Sutures - The body can not metabolize these non-absorbable suture anchors. Though it is not metabolized in the body the non-absorbable suture anchors are suitable for some cases like heart and blood vessels which require a longer time to heal. Some non-absorbable suture anchors are metal or plastic type. The major disadvantage of this type of suture anchor is that if it is used in shoulder repair it may cause a coconut scraper effect. The coconut scraper effect happens when the implant gets dislodged, this may lead to the most serious arthritic changes on the bone.

What Are the Conditions That Can Be Treated by Suture Anchors?

The medical orthopedic conditions that can be treated through suture anchors include:

• Avulsion fractures.

• Knee dislocation.

• Lateral epicondylitis.

• Bicipital tendon injuries.

• Collateral knee ligament pathology.

• Meniscal repair.

• Wrist arthroscopy.

• Superior labrum lesions.

• Stener lesion.

• Quadriceps tendon rupture.

• Perilunate fracture-dislocations.

• Medial humeral condyle fracture.

• Mannerfelt syndrome.

• Distal humerus fracture.

• Patellar tendon rupture.

• Posterior glenohumeral instability.

• Recurrent ankle sprains.

• Superior labral lesion.

• Triangular fibrocartilage complex injuries.

What Are the Methods of Suture Anchoring?

The suture anchors which are used to attach soft tissues like ligaments and tendons to the bone are done in three methods that include:

• Keyhole Tenodesis - This keyhole tenodesis requires a bone tunnel in a keyhole shape. Thus, creating a keyhole will allow the insertion of the knotted tendon into the upper portion and wedging of the knotted tendon into the lower narrow part where the tendon with inherited traction holds its place. It is a challenging technique as creating the keyhole site and inserting the tendon into the bone tunnel is difficult. The major drawback of this technique is that the tendon may slide out from the keyhole causing fixation loss of the knot in the tendon removed during the postsurgical period.

• Pull-Out Stitches - In this technique, the sutures anchored to the tendon end pass through the bone tunnel and are tied over a button or post on the joint's opposite side. The major denial of this technique is that it causes various post-surgical complications by causing potential injury to surrounding structures, wound problems, and weak fixation strength.

• Bond Tunnels - It is the most common method of attaching tendons to the bones by either interference screw fixation or suture fixation. It is a complicated method, as creating a tunnel requires deep exposure to identify its margin. Drill holes placed at 90 degrees are connected using small curettes. The main drawback of this technique is that it is a time-consuming procedure with high complications. This method may also cause fracture of the bone bridge and wrong tunnel placement. After the tunnel creation is done, the sutures must be inserted through the tunnels to create the passage of the tendon graft. The tunnels created should be small to allow tendon-bone contact, and the tunnels should also be significant to enable graft passage without interfering with the tendon. The breakage of bone bridge results in loss of fixation, a considerable disadvantage.

What Are the Guidelines for Using Suture Anchors?

• The surgeons should follow the manufacturer's instructions with familiar insertion techniques for the implant being used.

• The surgeons should use the drill guide for accurately placing the implants on the tuberosity or the glenoid rim. The suture anchors should be placed in the direct vision with adequate removal of soft tissues to confirm the anchor's position.

• The surgeons should be with backup plans if the device fails.

• The surgeons should be aware of placing anchors in the correct positions to prevent damage to the important structures of the bone.

Conclusion:

Suture anchors created an increasingly high positive impact on orthopedic surgeries. It is used to treat various orthopedic problems and various bone complaints. Suture anchors, if appropriately placed, give no post-surgical complications. Selecting the appropriate suture anchor materials to prevent postoperative complications is essential. Thus suture anchors are widely used in orthopedic surgeries with highly favorable results.