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OxBridge™ Ankle Fusion Nail Design Rationale & Surgical Technique

OxBridge™ Ankle Fusion Nail Clinical Design Team Design Goal - Simplifying the Complex BMBch MA FRCS (Trauma & Ortho) Tibiotalocalcaneal arthrodesis is a successful treatment for patients with severe pain and functional disability. Combined fusion of the ankle and subtalar joints is often used in the complex case, with significant bone loss or deformity. Consultant Orthopaedic Surgeon in Foot & Ankle Surgery at Nuffield Orthopaedic Centre, Oxford. UK Consultant Orthopaedic Surgeon in Foot & Ankle Surgery at Nuffield Orthopaedic Centre, Oxford. UK Consultant Orthopaedic & Trauma Surgeon,...

OxBridge™ Ankle Fusion Nail Dynamic or Static Locking Options Choice of dynamic and static proximal locking screw options allow dynamic loading of the nail if required. The nail is made from Titanium alloy (Ti6AI4V), Type II anodised. The material offers improved modulus of elasticity, fatigue strength and biocompatibility compared to stainless steel and is MRI compatible. Nail Sizing Three nail diameters (10mm,11mm & 12mm) each offering two nail lengths (150mm & 180mm) accommodate anatomical variation and reduce inventory requirements. 4 Low Profile Cortical Screws • Ultra low profile...

OxBridge™ Ankle Fusion Nail Instrumentation – Key Advantages Instrumentation System Outrigger Jig The outrigger jig has been designed to be simple, accurate and easy to use. The trigger mechanism allows for quick and easy rotation of the radial arm through medial, posterior and lateral positions around the nail axis. The radial arm is made from radiolucent PEEK to facilitate full X-Ray visualisation in multiple planes. The OxBridge instrument set and surgical technique have been designed to be as simple and straightforward as possible. All the instruments are supplied in one tray and laid...

OxBridge™ Ankle Fusion Nail Indications & Contraindications Indications: Relative/Absolute Contraindications Combined arthritis of the ankle and subtalar joints Failed Ankle Replacement Revision of failed ankle and / or subtalar fusion Revision of failed tibiotalocalcaneal (TTC) fusion Correcting neuromuscular imbalance of the hindfoot, where joint fusion is required Talar Avascular Necrosis Charcot neuroarthropathy of the hindfoot Trauma Rheumatoid arthritis Pre-Existing deep active infection Soft tissue defects, unless concomitant procedures planned Patients with psychiatric or...

OxBridge™ Ankle Fusion Nail 1/ Nail Entry Site The 8.0mm cannulated starter reamer (from OS333013 disposable pack) is advanced over the 3.9mm guide wire through the sole of the foot, reaming through the subtalar and tibiotalar surfaces, into the tibia (Fig 2a). It is useful to have an assistant hold the foot in the appropriate alignment during the transmedullary reaming, alternatively the foot position can be stabilised with threaded wires. Holding the foot in the correct alignment, the cannulated starter reamer is withdrawn, leaving the guide wire in place (Fig 2b). The exchange tube (from...

OxBridge™ Ankle Fusion Nail Remove the exchange tube. Sequential reaming is now carried out, using the flexible nitinol reamer shaft and modular heads (contained within the set). The canal is opened up (Fig 2e) in 0.5mm increments until reaming becomes tight, or the canal is reamed to 1mm greater than the diameter of the selected nail (Fig 2f). Make sure the 2.6 x 900mm olive tipped reaming rod (OS201526) is left in the tibia when the reamers are removed. The outrigger is designed for quick and simple assembly. Firstly, locate the Nail Alignment Shaft (B – OS333503) in the main Outrigger...

OxBridge™ Ankle Fusion Nail 4/ Rotating the Radial Arm around the Nail Axis To rotate the Main Outrigger Arm about the axis of the nail, and position the outrigger radial arm posteriorly, medially or laterally, depress the trigger (highlighted in blue) until the key disengages from the nail alignment shaft. This will allow the radial arm and the alignment shaft to freely rotate around the longitudinal axis of the nail. There are four key positions located at 90 degree intervals. The nail is advanced, through the sole of the foot, over the olive tipped reaming rod (Fig 5b). Usually the nail...

OxBridge™ Ankle Fusion Nail 6/ Proximal Tibial Screw Placement Drill until you feel drill penetration just through the lateral tibial cortex (Fig 6c). Then stop drilling. If necessary confirm the position of the tip of the drill and then note the desired screw length from the mark on the 4.0mm drill against the drill guide. Use the olive tipped reaming rod to confirm the drill has been correctly targeted through the nail. The wire, when reinserted up the nail, will be stopped by the drill if the drill is through the nail (Fig 6d) Next withdraw the olive tipped reaming rod a further two or...

OxBridge™ Ankle Fusion Nail TIP: If the guide wire is passed again from distal to proximal, it will be stopped at an earlier depth, indicating that the second drill has also passed through the nail. The long drill is removed. The drill guide is unscrewed from within the jig guide tube (again ensuring the guide tube remains in contact with the tibial cortex). Couple the pear shaped handle (OS333025) and the self-retaining screwdriver shank (OS333020). Load the tip of the driver with the selected 5mm cortical screw (Fig 6g). Advance the screw through the guide tube (Fig 6h). TIP: You can...

OxBridge™ Ankle Fusion Nail 8/ LM Distal Screw Placement Once compression has been applied, the radial arm is rotated to a lateral orientation (Fig 8). Using image intensification confirms that the distal screw positions will be in bone, distal to the ankle joint. The trocar and drill guide stack are passed through the holes marked L and an AP image is taken. The screws are inserted using the same technique described above for the tibial holes (Fig 8a). Once all screws have been inserted, check radiographs should be taken using the image intensifier, and images stored. If the preoperative...