Project Description:

Scapholunate ligament tears are a common wrist injury that typically present with similar symptoms to wrist sprains. If a patient with this injury does not receive treatment within the first six weeks, existing surgical solutions have been shown to have a 40-70% failure rate. Left untreated, patients will ultimately develop scapholunate advanced collapse (SLAC), a precursor to inevitable wrist arthritis. In order to discover the reason behind the high treatment failure rate, orthopedic surgeons and physical therapists were interviewed in tandem with an extensive literature search. It was found that, due to the complex three-dimensional nature of wrist movement, current solutions, like screws or reconstructions, are unable to properly withstand the internal forces of the wrist during normal range of motion. Through the identification of quantitative values for these internal wrist movements and categorization of commercially available materials that are both biocompatible and mechanically strong, a new solution was developed. The WRISTraint is a titanium orthopedic implant designed to maintain the integrity of scapholunate ligament repairs and reconstructions by fixating the scaphoid, lunate, and capitate bones together to prevent internal micromovements that could worsen the injury. This claim was tested and validated through the use of OXOS Medical’s Micro C X-Ray during a cadaver lab. The device was implanted into a cadaver arm, and key physical movements, such as flexion/extension of the wrist and opening/closing of the fingers, were sufficiently performed, demonstrating the effectiveness of the WRISTraint at keeping the targeted bones in a constant position relative to each other. By using the WRISTraint in conjunction with current repair and reconstruction techniques, surgeons will be able to improve patient outcomes, saving patients’ time and money.