What is a Circular Frame Application?
A circular frame application is an orthopedic medical device that is applied on the surface of the skin to hold bone(s) in an intended position. A circular frame is a specialized type of external fixator that surrounds a limb and is secured to the bone utilizing pins or wires. The frame functions like a cage or scaffold around the limb, providing support and stability. This enables weight-bearing and normal function while the issue with the bone is managed. The frame consists of adjustable rings and struts that allow bones to be moved, angled, or rotated to achieve correct bone alignment and function while healing. The different types and brands of circular frames include Ilizarov, T-L Hex, Taylor spatial frame (TSF), and Maxframe.
Indications for Circular Frame Application
Your surgeon may recommend a circular frame application when other stabilizing alternatives such as a plaster cast, metal rods or metal plates, or other methods have been used and failed. The most common conditions that require a circular frame application include:
- A limb, foot, or ankle deformity
- Lengthening of a short limb
- Complex fractures such as open fractures
- Unhealed or improperly healed fracture
- Conditions with poor soft tissue healing potentials
- Osteomyelitis (bone infection)
Preparation for Circular Frame Application
In general, preoperative preparation for circular frame application will involve the following steps:
- A thorough examination of the patient’s limb is performed by your physician for measurement of any clinical deformities (angular, rotational, or translational) and limb lengths.
- Physical examination also involves assessment of gait pattern, long bone torsion, ligamentous laxity, and patellar tracking.
- Depending on your medical history, social history, and age, you may need to undergo tests such as blood work and imaging to help detect any abnormalities that could compromise the safety of the procedure.
- You will be asked if you have allergies to medications, anesthesia, or latex.
- You should disclose any medications or supplements you are taking or any conditions you have such as heart or lung disease.
- You may be asked to stop taking certain medications, such as blood thinners, anti-inflammatories, or other supplements for a week or two.
- You should refrain from alcohol and tobacco for at least a few days prior to surgery and several weeks after, as these can hinder the healing process.
- You should not consume any solids or liquids at least 8 hours prior to the procedure.
- You should arrange for someone to drive you home after the procedure.
- A signed informed consent form will be obtained from you after the pros and cons of the procedure have been explained.
Procedure for Circular Frame Application
Circular frames are commonly employed to correct a tibial fracture or foot and ankle deformity. Circular frame application for bone deformity correction is performed by an orthopedic surgeon, usually under general anesthesia, and typically involves the following steps:
- After adequately sterilizing the surgical area, your surgeon makes an incision around the deformed bone.
- The supporting structures around the bone are gently moved out of the way to view the deformed or fractured bone and adjoining soft-tissue structures.
- Your surgeon may perform an osteotomy to correct the bone deformity or reposition or realign the fractured bones into a normal position.
- Using fluoroscopy (live X-ray imaging), holes are drilled into the undamaged portions of the bone around the fracture or deformity.
- Metal pins or screws are then placed into these holes on both sides of the fracture.
- The pins and screws are secured together outside the skin, utilizing a series of rods and clamps known as the external circular frame.
- The pins and screws, along with the external rods and clamps, hold the bone in place and stabilize it while facilitating proper healing of the newly aligned bone.
- The frame may remain in place for 4 to 6 months until the bone deformity is corrected.
- Adjustments can be made to the frame from the outside to ensure the bone is appropriately aligned with little, if any, shortening of the bone.
- Surrounding tissues and structures are restored to their normal anatomical positions, and bandages are wrapped around the sections where the pins are placed and secured.
Postoperative Care and Recovery
In general, postoperative care and recovery after circular frame application involve the following steps:
- You will be transferred to the recovery area where your nurse will closely observe you for any allergic/anesthetic reactions and monitor your vital signs.
- You may experience significant pain and swelling in the area of the circular frame application. Medications are provided as needed to address these.
- Antibiotics are also prescribed to mitigate the risk of surgery-related infection.
- You are advised to keep your leg elevated as much as possible while resting to prevent swelling and pain.
- Do not weight-bear on the operated leg. Assistive devices such as crutches or walkers are recommended throughout the healing period to support the leg. You are encouraged to walk with assistance as frequently as possible to prevent the risk of blood clot formation.
- Instructions on surgical site care and bathing will be provided to keep the wound clean and dry.
- You should refrain from any strenuous activities for at least 6 months. A gradual increase in activities is recommended with your doctor’s guidance.
- A physical therapy protocol may be recommended if necessary to help strengthen limb muscles and optimize limb function.
- A periodic follow-up appointment will be scheduled to monitor your progress.
- Once the bone deformity is deemed to be corrected, your surgeon will remove the device in an outpatient surgery setting.
Risks and Complications
Bone deformity correction with the application of a circular frame is a relatively safe procedure; however, as with any surgical procedure, it does carry some risks and complications, including:
- Chronic pain
- Blood clots
- Joint stiffness
- Loss of function
- Injury to nerves and blood vessels
- Anesthetic-related complications
- Leg-length discrepancy
- Failure of the treatment