Correction to d.3.And g.1.: updated from 'stryker spine- leesburg' to 'k2m, inc.' visual inspection: visual analysis could not be performed; however, x-rays were provided.The construct, spanning levels t10-s2, appears to have minimal overhang length at the distal end on both sides of the construct.Upon review of the one-year post-op x-ray, it can be confirmed that bilateral screws at the distal end of the construct slipped axially along their associated rods.Dimensional, material and functional analysis could not be performed as the device was not returned.A review of the device history and complaint history records could not be performed as a valid lot code was not provided and could not be obtained.Per surgical technique: note: ensure at least 5 mm of rod overhang from the most proximal and distal screw (p.24).Potential adverse events associated with spinal fusion procedures include, but are not limited to pseudoarthrosis; loosening, bending, cracking or fracture of components, or loss of fixation in the bone with possible neurologic damage, usually attributable to pseudoarthrosis, insufficient bone stock, excessive activity or lifting, or one or more of the factors listed in contraindications, or warnings and precautions; infections possibly requiring removal of devices; palpable components, painful bursa, and/or pressure necrosis; and allergies, and other reactions to device materials which, although infrequent, should be considered, tested for (if applicable), and ruled out preoperatively.Screws placed at the most caudal end of the construct are subjected to more stress.It is possible that post-operative patient activities may have introduced unanticipated loading in the most caudal level of the construct, which may have surpassed the capture strength of the screw and resulted in rod slippage.Minimal overhang length may have also contributed to the failure.At least 5 mm of rod overhang from the most proximal and distal screw is recommended in the mesa surgical technique guide.It could not be determined if the screws were fully locked in the index surgery.
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