A visual assessment of the returned system screwdrivers showed instruments with minimal use, as identified by crisp laser marks and a lack of surface scratches.The distal tips of the complaint instruments were fractured perpendicularly at approximate depth of the system screws.A visual assessment of the returned torque-limiting handles showed instruments with repeated use, as identified by worn laser markings and surface scratches.The proximal ends of both torque-limiting handles were damaged and appear to have been repeatedly impacted.When the complaint communication was received that suggested a possible problem with the system screwdrivers, internal measurement and functionality verifications were performed on the complaint lot.Critical measurements of the driver tip dimensions were confirmed to be correct.A calibrated torque-limiting handle (40 in-lbs +/- 10%) was used with a system screwdriver from the complaint lot, which was unable to replicate the reported instrument malfunction when final tightening a system implant.The torque-limiting handle and driver were repeatedly rotated to ensure the driver could withstand multiple cycle of rotation and torque-limiting force.The reported instrument malfunction was also attempted to be recreated by repeatedly rotating the system screwdriver at an angle, as well as rotating the driver while partially seated in a system screw.The distal tip of the system screwdriver did not fracture.The company was unable to confirm any quality problems with the complaint lot.Dhr reviews were performed for the complaint system screwdriver lot and the returned torque limiting handles and there were no manufacturing anomalies identified.The devices met all required specifications prior to being released to distributable inventory.The complaint lot has been available for distribution since (b)(6) 2020 and the manufacturer has not received any similar complaints.The returned torque limiting handles were tested at the manufacturer on a calibrated torque testing instrument and both repeatedly produced results out of specifications.The system torque limiting handles are intended to limit applied torque to 40 in-lbs +/-10%.The returned torque limiting handles produced results between 50-62.45 in-lbs, which is significantly more than specification for the devices.To reproduce the complaint malfunction, both returned torque limiting handles that were out of spec were tested with the system screwdriver complaint lot.Rotation of the system screwdriver with the out of spec torque limiting handles resulted in the system screwdrivers fracturing in the same manner as the complaint drivers.The returned torque limiting handles were purchased by the complainant (b)(6) 2016 and have not since been verified to be within tolerance for torque-limiting capabilities.Over time and repeated use torque-limiting handles may not effectively limit applied torque.Damage to the torque-limiting handle may also result in the instrument not effectively limiting applied torque.The returned torque-limiting handles were damaged on the proximal end, indicating they had been repeatedly impacted.The torque-limiting handle manufacturer instructions for use states, "do not impact this device, or use this device to impact other devices." the root cause of this complaint is using torque-limiting handles that were out of spec and did not appropriately limit applied torque, which resulted in instrument malfunctions.
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The company received notification on (b)(6) 2021 that the distal tips of two system screwdrivers fractured while being used to final tighten a system implant.There were no known patient complications associated with this complaint.The procedure was successfully completed using available alternate instruments.The torque limiting handles that were being used when the malfunction occurred were requested to be returned to the company with the complaint instruments.This mdr is associated with reports 3005031160-2021-00007, 3005031160-2021-00009, and 3005031160-2021-00010.
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