Total shoulder replacements are the third most common orthopaedic procedures in Canada, following hip and knee arthroplasty. Shoulder surgery is an effective and durable solution to treat severe pain due to osteoarthritis, torn rotator cuffs and fractures of the humeral head. In order to restore normal shoulder motion, the implanted prosthesis is rigidly affixed to bone using a medical grade acrylic cement. However, most implants last approximately 10-15 years after which they need to be removed and replaced due to poor initial alignment, infection, loosening or abuse.
Orthopaedic revision surgery of a humeral implant can be extremely challenging, especially when it has been thoroughly cemented to the bone. Under these conditions, several methods have been employed to dislodge the implant from the cement mantle. For example, if a humeral stem needs to be removed shortly after surgery, a slap hammer may be used prior to full bonding. If the cement has cured, ultrasonic cement extraction, osteotomes or pressurized extraction using a separating fluid can rupture the cement bond.
Unfortunately, each of these methods can cause significant collateral damage to a patient’s peripheral tissues and bones, thereby extending healing times and enhancing the risk of infection. The uncertainty around which method will eventually be successful is also an issue for scheduling surgical resources and people.
In order to address these limitations, engineering scientists have developed a novel orthopaedic tool for extracting a long stem implanted prosthesis. This is an innovative device that promises to revolutionize orthopaedic procedures worldwide.
With its patented technology, the tool combines a handle and adaptable cap system to facilitate the interaction between a modular attachment and the implant stem. By channelling the surgeon’s external force, applied via the lever-attachment interface, the implant receives controlled and focused kinetic energy, facilitating its extraction, thereby minimizing incidental damage.
In contrast, osteotomes (with a mallet) and pressurized extraction techniques pose a high risk of fracture, while ultrasonic cement extraction generates extreme heat capable of significant trauma to surrounding tissues. Additionally, the slap hammer is limited to revision surgeries within a narrow window of the original procedure to repair loosened implants prior to cement fixation.
This Extractor technology features interchangeable caps and attachments that cater to a patient’s individual implant type, while its unique force distribution should result in fewer complications and a more predictable surgery time.