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The complaint alleges that the nail was used as a part of a pabst surgery for a distal screw exchange.The nail was distracted 48mm for the initial transport, with the plan being to recharge the nail for an additional 40mm of distraction.There were no complications with distracting the nail, but upon removing the distal screws and attempting a recharge with a pfd2-000 fast distractor max, the nail would not retract at all.The nail was returned to globus medical for investigation.The dhr was reviewed and showed the nail passed all inspections and was manufactured to the specifications that were current at the time of manufacturing.The production x-rays did not present any abnormalities for any nail in the lot.After cleaning, it was measured at 265.22mm.This suggests the nail was fully distracted since this was a 50-stroke nail.X-rays were then taken with one x-ray showing the distraction nut disengaged with the lead screw (see x-ray, "distraction nut and anti-rotation lug").The remaining internal components did not show any defects or damage.The nail was placed in the stroke fixture for retraction where it was able to fully retract to 214.66mm.The nail was then placed in a distraction force fixture where it was unable to produce the required 180lbs of force.Retraction force was unable to be tested.With the nail fully distracted in the patient, what most likely happened was that either with the erc or fast distractor max, the distraction rod became disengaged with the lead screw.With the distal locking screws removed, and the leg in a flexed position, the antegrade nail would have the distraction rod pointing towards the operating table, and gravity would not allow the distraction rod to catch back on to the lead screw, meaning that no matter how long the fast distractor max would use, the lead screw would be rotating, but the distraction rod would not move.When the nail was tested with the stroke test fixture, the nail was placed in the fixture with the distraction rod pointing up, allowing gravity to pull the distraction rod towards the lead screw as it was spinning.This caused the distraction nut to thread with the lead screw, and retraction and distraction could then occur.Rate is within the predicted rated, no new harm determined.The associated risk document was reviewed, and the failure mode, effects, and harms potentially related to the reported event have been identified and mitigated.Furthermore, the complaint rate is within the estimated rate in the risk documentation associated with this product.Based on this risk assessment, no new or additional risk evaluation is necessary.The following sections were updated for this supplemental report: b4, d4, d9, e, e2, e3, e4, g3, g6, h2, h3, h6, h10.
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