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Visual inspection of the returned device confirmed that the threaded distal tip of the installer was fractured.The distal thread couples the lateral plate to the installer and is subjected to cantilever bending loads during impaction as the plate spikes are driven into the bone.Uneven anatomical surfaces may cause the plate spikes to engage the bone at different times, resulting in asymmetric loading and increased bending stress at the distal threaded connection.Based on the observed fracture and intended use of the device, the failure mode is consistent with fracture of the distal thread due to excessive bending loads during implant insertion, potentially amplified by uneven engagement of the plate spikes with the bone.Due to the age and service history of the device, fatigue damage from repeated use may have been a contributing factor.Fatigue damage would progressively reduce the load bearing capacity of the threaded feature until final fracture occurred during the reported use.
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