What is INBONE™ Total Ankle System?
INBONE™ Total Ankle System is an innovative and distinctive total ankle replacement system used for the treatment of ankle arthritis and involves the surgical removal of a painful and dysfunctional ankle joint and replacing it with the state-of-the-art INBONE™ total ankle system prosthetic device.
The INBONE™ total ankle system comprises of a tibial tray, a talar dome with a modular talar stem, a four-component tibial stem assembly that connects to the tibial tray, and an ultra-high molecular weight polyethylene insert (UHMWPE). The prosthetic device has anchoring stems to secure it in position, within both the talus and tibia. All implant components are available in several varying sizes to best match the ankle anatomy of the patient. The INBONE™ total ankle system is a modular prosthetic device installed through the first and only intra-medullary alignment PROPHECY™ INBONE™ system which guides your surgeon in preoperative planning of your ankle replacement and assists in precise sizing, alignment, and placement of ankle components during surgery.
Some of the key features of INBONE™ total ankle system over a traditional prosthesis include:
- Refined instrumentation: All-inclusive set of trial components to enable accurate size determination and anatomic component placement
- Comprehensive sizing: Longer tibial tray sizing choices to establish optimum cortical coverage
- Talar fixation: Extra talar dome “pegs” allow for additional fixation in the talus
- Sulcus design: New articular geometry allows enhanced tibio-talar stability
Anatomy of the Ankle Joint
The ankle joint connects the leg to the foot, and comprises three bones: the tibia, fibula, and talus. The tibia (shinbone) and fibula (calf bone) are the bones of the lower leg that articulate with the talus (ankle bone), enabling up-and-down movement of the foot. The joint surfaces of all these bones are lined by a thin, tough, flexible, and slippery surface called articular cartilage, which acts as a shock absorber to cushion and reduce friction between the bones.
Arthritis is the inflammation of a joint as a result of degeneration of the smooth cartilage that lines the ends of the bones within. This degeneration of cartilage causes painful rubbing of the bones, leading to swelling, joint stiffness, and restricted movement.
Indications for INBONE™ Total Ankle System
INBONE™ total ankle system may be indicated when conservative treatments such as medications, injections, or physical therapy have failed to resolve painful symptoms in the ankle joints caused by:
- Primary osteoarthritis
- Posttraumatic osteoarthritis
- Rheumatoid arthritis
- Failed previous ankle surgery
Preparation for INBONE™ Total Ankle System
Preoperative preparation involved in the placement of INBONE™ total ankle system may involve the following steps:
- A thorough examination is performed by your doctor to check for any medical issues that need to be addressed prior to surgery.
- 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 inform your doctor of any medications, vitamins, or supplements you are taking.
- You may be asked to refrain from supplements or medications such as blood-thinners or anti-inflammatories for a week or two prior to surgery.
- You should refrain from alcohol or tobacco at least a few days prior to surgery.
- You should not consume any solids or liquids at least 8 hours prior to surgery.
- Arrange for someone to drive you home after surgery, as you may be groggy.
- A written consent will be obtained from you after the surgical procedure has been explained in detail.
Procedure for INBONE™ Total Ankle System
Ankle joint replacement surgery with INBONE™ total ankle system is performed under sterile conditions in the operating room under general or regional anesthesia and involves the following steps:
- An incision is made over the front of the ankle.
- The muscles are retracted, and tendons and ligaments are moved away to expose the ankle joint. Care is taken with nerves to prevent nerve damage.
- The leg bones are then separated from the talus bone.
- The damaged joint surfaces of the tibia and fibula are cut off with a surgical saw to allow for a smooth surface for which to attach the tibial component of the INBONE™ total ankle system implant.
- Next, your surgeon will cut the top of the talus bone for insertion of the talar component of the INBONE™ total ankle system prosthesis.
- The tibia and talus bones are then prepared with or without cement, depending on the surgeon’s preference.
- The components are then inserted and put together ensuring proper movement of the prosthesis.
- Screws are inserted above the artificial joint between the tibia and fibula to ensure a tight fit of the new prosthesis.
- A bone graft is taken from the portion of bone cut off and is inserted between the tibia and fibula to create a fusion of the two bones. This helps to prevent loosening of the prosthesis.
- With all the new components in place, the ankle joint is tested through its range of motion.
- The surgeon then irrigates the new joint with sterile saline solution.
- The surgeon then sutures the joint capsule together, repairs the muscles and tendons, and sutures the skin closed usually with a drain in place to help any blood drain from the area.
- The ankle is then dressed and bandaged and placed in a splint.
Postoperative Care and Recovery
In general, postoperative care instructions and recovery after INBONE™ total ankle system placement will 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 as you recover.
- You may notice some pain, swelling, and discomfort in the foot area. Pain and anti-inflammatory medications are provided as needed.
- Antibiotics are also prescribed to address the risk of surgery-related infection.
- Do not weight-bear on the operated leg. A walking boot or a non-weight-bearing cast is recommended for few weeks to facilitate healing and support the foot.
- Assistive devices such as crutches and walkers are recommended to maintain balance and stability while walking for several weeks.
- Keep the foot elevated at or above the level of your heart for a specified period to help minimize swelling and discomfort.
- Start rehabilitation (physical therapy) as recommended by your surgeon to improve range of motion. You should begin exercises to stretch and strengthen the foot muscles.
- Eating a healthy diet and refraining from smoking helps to promote faster healing.
- Keep the surgical site clean and dry. Instructions on surgical site care and bathing will be provided.
- Refrain from strenuous activities and lifting heavy weights for at least 6 months. Gradual increase in activities over a period of time is recommended.
- A periodic follow-up appointment will be scheduled to monitor your progress.
Risks and Complications
INBONE™ total ankle system placement is a relatively safe procedure; however, as with any surgery, some risks and complications may occur, such as the following:
- Failure to relieve pain
- Damage to nerves and vessels
- Thromboembolism or blood clots
- Aseptic loosening of the prostheses
- Delayed healing or failure to heal