D3 and g1: updated from stryker spine-leesburg to k2m, inc.Post-operative x-rays were provided by the rep.Analysis of the x-rays revealed that the subject screws were implanted bilaterally at the most caudal level of the construct, at s1.Dimensional, functional, and material analysis could not be performed as the device was not returned.A review of the device and complaint history records could not be performed as a valid lot code was not provided and could not be obtained since the device associated with this event was not returned.The everest surgical technique was reviewed and the following relevant information was identified: adequately instruct the patient.Postoperative care and the patient's ability and willingness to follow instructions are two of the most important aspects of successful healing.Internal fixation devices are load sharing devices which maintain alignment until healing occurs.If healing is delayed or does not occur the implant could eventually break, bend or loosen.Loads produced by load bearing and activity levels will impact the longevity of the implant.Metallic implants can loosen, fracture, corrode, migrate, cause pain, or stress shield bone even after a bone has healed.If an implant remains implanted after complete healing, it can actually increase the risk of refracture in an active individual.The surgeon should weigh the risks versus benefits when deciding whether to remove the implant.Implant removal should be followed by adequate postoperative management to avoid refracture.Periodic x-rays for at least the first year postoperatively are recommended for close comparison with postoperative conditions to detect any evidence of changes in position, nonunion, loosening, and bending or cracking of components.With evidence of these conditions, patients should be closely observed, the possibilities of further deterioration evaluated, and the benefits of reduced activity and/or early revision considered.Surgical implants must never be reused.An explanted metal implant should never be reimplanted.Even though the device appears undamaged, it may have small imperfections and internal stress patterns which may lead to early breakage.Analysis of the x-rays revealed that the subject screws were implanted bilaterally at the most caudal level of the construct, at s1.Both screws had fractured approximately mid-shaft.As the screws were not available for evaluation, the root cause could not be determined conclusively.It is possible that failure occurred in fatigue.Screws at the most caudal level of the construct are subjected to more stress.Dynamic motions can compound cantilever forces, resulting in screw fracture.
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