Performance and Safety Evaluation of Inion CompressOn Screw in Foot and Ankle Surgeries. PMCF Investigation

The study in question is a post market clinical follow-up study to evaluate the safety and performance of bioabsorbable headless compression screw Inion CompressOn in selected fracture, osteotomy and arthrodeses operations of the foot and ankle. The main focus of the study in terms of performance is to evaluate the bone healing/ossification of operated areas. The main focus of the study in terms of safety is to evaluate the occurrence of adverse events and required revision surgeries that are or might be related to the study device.

The Inion CompressOn™ screws are cannulated headless compression screws made of degradable co-polymers composed of L-lactic acid and D-lactic acid. These polymers have a long history of safe medical use and they degrade in vivo by hydrolysis into alpha-hydroxy acids that are metabolised by the body. The screws retain their initial strength up to 12 weeks after implantation and gradually lose their strength thereafter. Bioabsorption takes place within two to four years. The Inion CompressOn™ products are intended for maintenance of alignment and fixation of bone fractures, comminuted fractures, osteotomies, arthrodeses or bone grafts (i.e., autografts or allografts) in the presence of appropriate additional immobilization (e.g., rigid fixation implants, cast or brace).

In the field of foot and ankle traumatology the surgical indications of this study include medial malleolar fractures, Lisfranc injuries, talus fractures, calcaneal fractures and navicular bone fractures. In the field of foot and ankle orthopaedics the surgical indications of the study include arthrodesis of the talonavicular joint, calcaneacuboideal joint, tarsometatarsal joint and first metatarsophalangeal (MTP1) joint, and osteotomies of the first metatarsal bone, second metatarsal bone (weil) and calcaneal bone.

The clinical data collection acquired from this study is a requirement of the EU Notified Body as part of the admitted CE mark certification, in cases when the device is initially approved based on the clinical data of an equivalent device. In this case, the equivalent device has been Inion FreedomScrew, which is made of the same material composition and has the same indications for use. Inion CompressOn Screw has new design features such as headless design, and threading which allows compression to the fracture line. Also new sizes are introduced.

The study recruits 125 adult patients who meet the acceptance criteria and have signed the informed consent. The follow-up time for each study patient is 4 years. Each patient has 6 follow-up time points related to the study. These time points consist of: