Anchor screws Introduction, Uses, Sizes & Surgical Technique.

Anchor Screws

Anchor screws are broadly used for attaching soft tissue (e.g., tendons, ligaments, and meniscus) to the bone and have become essential devices in sports medicine and during arthroscopic surgery. As the usage of anchor has increased, various material-specific advantages and challenges have been reported. As a result, anchors are continually changing to become safer and more efficient.

Anchor screws are designed with self-drilling and self-tapping tips to achieve rapid and secure fixation. The eyelet allows visual assessment of tension and anchor rotation angle as the soft tissue is being reattached.

Anchor screws Uses

The use of Anchor screws have revolutionized orthopedic surgery because it allows for simple and efficient fixation of soft tissue (e.g., tendons and ligaments) to the bone in both open and arthroscopic surgery around the shoulder, elbow, wrist, and lower limb joints.) Shoulder surgery particularly has experienced a significant change in the type of techniques used from open repair of the rotator cuff and labrum using screws, washers, transosseous and staples to arthroscopic repair using anchors.

Suture Anchors screws Uses 1

Suture Anchors screws Uses 2

Anchor screws Inserting

The anchor is inserted through the fracture line into bone. The anchors need to be placed sufficiently deep so that the metal part does not protrude above the fracture.

In repairing the soft tissue and small bony fragments, the anchor is placed as close as possible to the articular margin. Once the anchor is securely seated in bone, the handle is removed.

An appropriately angled suture passer is used to shuttle one suture through the labrum.

The sutures are then tied and as the knot is tightened, the fracture is reduced.

The procedure is repeated for any other fragments not suitable for screw fixation.

At the end of the procedure, use the image intensifier to check the placement of fixation devices and the reduction of the joint.

Aftercare

The neurovascular status of the extremity must be carefully monitored. Impaired blood supply or developing neurological loss must be investigated as an emergency and dealt with expediently.

Functional treatment
Functional treatment shall be applied for 2 – 3 days with patient still resting in bed starting on postoperative day 1.
The goal of early active and passive range of motion is to achieve a full range of motion within the first 4 – 6 weeks. Maximum stability is achieved at the time of surgery.
In noncompliant patients consider the use of a hinged knee brace.

Weight bearing
The patient can be fully weight bearing but care must be taken not to apply a varus distracting force. For this reason, crutches are advisable as a means of protection.

Follow up
Wound healing should be assessed on a short term basis within the first two weeks. Subsequently a 8 week follow-up is usually performed.

Anchor screws removal
Anchors screws removal is not mandatory and should be discussed with the patient.

Do you have any questions for Anchor screws?
Please fill this form we will get in touch with you shortly.

Different Types of Screws including Anchor screws

Locking Cortical Screws

Cortical Screws

1.5 mm Cortical Screws
2 mm Cortical Screws
2.4 mm Cortical Screws
2.7 mm Cortical Screws
3.5 mm Cortical Screws
4.5 mm Cortical Screws

Locking Cancellous Screws

3.5 mm Locking Cancellous Screw
4 mm Locking Cancellous Screw
5 mm Locking Cancellous Screw
6.5 mm Locking Cancellous Screw

Cancellous Screws

Locking Cannulated Screws

4 mm Locking Cannulated Screw
5 mm Locking Cannulated Screw
6.5 mm Locking Cannulated Cancellous Screw
7.3 mm Locking Cannulated Cancellous Screw

Cannulated Screws

3.5 mm Cannulated Screws (Cortical Thread)
4 mm Cannulated Cancellous Screws
4.5 mm Cannulated Cancellous Screws
6.5 mm Cannulated Cancellous Screws
7 mm Cannulated Cancellous Screws
7.3 mm Cannulated Cancellous Screws

Headless Screws Full Thread

2.5 mm Headless Compression Screws Full Thread
3 mm Headless Compression Screws Full Thread
3.5 mm Headless Compression Screws Full Thread
4 mm Headless Compression Screws Full Thread
4.5 mm Headless Compression Screws Full Thread
5 mm Headless Compression Screws Full Thread
5.5 mm Headless Compression Screws Full Thread
6.5 mm Headless Compression Screws Full Thread

Headless Screws Partially Thread

2.5 mm Headless Compression Screws Partially Thread
3 mm Headless Compression Screws Partially Thread
3.5 mm Headless Compression Screws Partially Thread
4 mm Headless Compression Screws Partially Thread
4.5 mm Headless Compression Screws Partially Thread
5.5 mm Headless Compression Screws Partially Thread
6.5 mm Headless Compression Screws Partially Thread
7.5 mm Headless Compression Screw Partially Thread

Interlocking Nail Screws

Interference Screws

5 mm Interference Screw
6 mm Interference Screw
7 mm Interference Screw
8 mm Interference Screw
9 mm Interference Screw
10 mm Interference Screw

Herbert Screws

2.5 mm Cannulated Herbert Screws
3 mm Cannulated Herbert Screws
3.5 mm Cannulated Herbert Screws
4.5 mm Cannulated Herbert Screws
5.5 mm Cannulated Herbert Screws
6.5 mm Cannulated Herbert Screws

Craniomaxillofacial Screws

1.5 mm Screw Craniomaxillofacial
2 mm Screw Craniomaxillofacial
2 mm Locking Screw Craniomaxillofacial
2.5 mm Screw Craniomaxillofacial
2.5 mm Locking Screw Craniomaxillofacial
2.8 mm Screw Craniomaxillofacial
2.8 mm Locking Screw Craniomaxillofacial
2.7 mm Emergency Screw

Malleolar Screws

Bone screws are the most commonly used orthopedic implants. There are many different types and sizes of screws for different types of bones. Most bone screws are made out of stainless steel or titanium alloys. The outer diameter, root diameter, and thread pitch and angle are important in determining screw mechanics.

In orthopedics, screws are typically described by their outer diameter, for example, a “5 mm Anchor screws” has an outside diameter of 5 mm. The pitch of a screw is the linear distance travelled by a screw for one full turn of the screw. The screw advances by a distance equal to the distance between the threads with each full turn. Cortical screws have a lower pitch and therefore more number of threads. Cancellous bone screws have a greater depth of the screw to increase the surface area and therefore improve the purchase, as the bone is weaker.

Screws function by converting the tightening torque into internal tension in the screw and elastic reactions in the surrounding bone. This creates compression between the fracture fragments that the screw is holding together. Screw is typically inserted into holes drilled equal to the root diameter and are either self-tapping or are inserted tapped (threaded) holes. The torque to insert cortical bone screws can be high, so the screws must be properly inserted into the correct size drilled hole and designed to withstand insertion torque levels expected in cortical bone. Cancellous bone screws have large, deep threads that grip the spongy bone well. Because of the relatively low strength of the cancellous bone, failure of the screw itself during insertion is rare, but pull out can be an issue.

Anchor screws Contraindications

Contraindications may be qualified or total, and need to be taken into consideration when evaluating the prognosis in each case. The physician’s education, training and professional judgement must be relied upon to choose the most appropriate device and treatment. Conditions presenting an increased risk of failure include:

Any active or suspected latent infection or marked local inflammation in or about the affected area.
Compromised vascularity that would inhibit adequate blood supply to the fracture or the operative site.
Bone stock compromised by disease, infection or prior implantation that can not provide adequate support and/or fixation of the devices.
Material sensitivity, documented or suspected.
Obesity. An overweight or obese patient can produce loads on the implant that can lead to failure of the fixation of the device or to
failure of the device itself.
Patients having inadequate tissue coverage over the operative site.
Implant utilization that would interfere with anatomical structures or physiological performance.
Any mental or neuromuscular disorder which would create an unacceptable risk of fixation failure or complications in postoperative care.
Other medical or surgical conditions which would preclude the potential benefit of surgery.
All associated diseases which could endanger the function and success of the Anchor screws.

Warnings and Precautionary for Anchor screws

Before using Anchor screws, the surgeon and ancillary staff should study the safety information in these instructions, as well as any product-specific information in the product description, surgical procedures and/or brochures.

Screws are made from medical grade materials and are designed, constructed and produced with utmost care. These quality screw assure best working results provided they are used in the proper manner. Therefore, the following instructions for use and safety recommendations must be observed.

Improper use of screw can lead to damage to the tissue, premature wear, destruction of the instruments and injury to the operator, patients or other persons.

It is vital for the operating surgeon to take an active role in the medical management of their patients. The surgeon should thoroughly understand all aspects of the surgical procedure and instruments including their limitations. Care in appropriate selection and proper use of surgical instruments is the responsibility of the surgeon and the surgical team. Adequate surgical training should be completed before use of implants.

Factors which could impair the success of the operation:

Allergies to implanted materials.
Localized bone tumours.
Osteoporosis or osteomalacia.
System disease and metabolic disturbances.
Alcohol and drug abuse.
Physical activities involving excessive shocks, whereby the implant is exposed to blows and/or excessive loading.
Patients who are mentally unable to understand and comply with the doctor’s instructions.
Poor general health.

Possible Adverse Effects

The following adverse effects are the most common resulting from implantation:

Loosening of the screw, which may result from cyclic loading of the fixation site and/or tissue reaction of the implant.
Early and late infection.
Further bone fracture resulting from unusual stress or weakened bone substance.
Temporary or chronic neural damage resulting from pressure or hematomata.
Wound hematomas and delayed wound healing.
Vascular disease including venal thrombosis, pulmonary embolism and cardiac arrest.
Heterotopic ossification.
Pain and discomfort due to presence of the implants.
Mechanical failure of the implant, including bending, loosening or breakage.
Migration of implant resulting in injury.

Preoperative Planning for Anchor screws

The operating planning is carried out following a thorough clinical evaluation of the patient, Also, x-rays must be taken to allow a clear indication of the bony anatomy and associated deformities. At the time of the operation, the corresponding implantation instruments in addition to a complete size of Anchor screws must be available.

The clinician should discuss with the patient the possible risks and complications associated with the use of implants. It is important to determine pre-operatively whether the patient is allergic to any of the implant materials. Also, the patient needs to be informed that the performance of the device cannot be guaranteed as complications can affect the life expectancy of the device.

Anchor screws Precautions

Confirm functionality of instruments and check for wear during reprocessing. Replace worn or damaged instruments prior to use.
It is recommended to use the instruments identified for this screw.
Handle devices with care and dispose worn bone cutting instruments in a sharps container.
Always irrigate and apply suction for removal of debris potentially generated during implantation or removal.

Anchor screws Warnings

Anchor screws can break during use (when subjected to excessive forces). While the surgeon must make the final decision on removal of the broken part based on associated risk in doing so, we recommend that whenever possible and practical for the individual patient, the broken part should be removed. Be aware that implants are not as strong as native bone. Implants subjected to substantial loads may fail.
Instruments, screws and cut plates may have sharp edges or moving joints that may pinch or tear user’s glove or skin.
Take care to remove all fragments that are not fixated during the surgery.
While the surgeon must make the final decision on implant removal, we recommend that whenever possible and practical for the individual patient, fixation devices should be removed once their service as an aid to healing is accomplished. Implant removal should be followed by adequate post-operative management to avoid refracture.

Anchor screws General Adverse Events

As with all major surgical procedures, risks, side effects and adverse events can occur. While many possible reactions may occur, some of the most common include: Problems resulting from anesthesia and patient positioning (e.g. nausea, vomiting, dental injuries, neurological impairments, etc.), thrombosis, embolism, infection, nerve and/or tooth root damage or injury of other critical structures including blood vessels, excessive bleeding, damage to soft tissues incl. swelling, abnormal scar formation, functional impairment of the musculoskeletal system, pain, discomfort or abnormal sensation due to the presence of the device, allergy or hypersensitivity reactions, side effects associated with hardware prominence, loosening, bending, or breakage of the device, mal-union, non-union or delayed union which may lead to breakage of the implant, reoperation.