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Analysis of historical records: orthofix srl checked the internal records related to the controls made on the device code 99-612640 lot 25446585 (lot marked on component) before the market release.No anomalies have been found.The original lot, manufactured in 2017, was comprised of 150 devices.All of them have already been distributed to the market.According to orthofix srl historical records, this is the first notification received from this specific device lot.Technical evaluation: the device involved in this event has been received at orthofix srl on august 6, 2020.The technical evaluation is in progress.Medical evaluation: the information available on the case was sent to our medical evaluator.A preliminary medical evaluation was performed and will be finalized once the results of the technical evaluation become available.As soon as the results of the investigation are available, orthofix srl will provide a follow up report.Orthofix srl continues monitoring the devices on the market.
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The information provided by the hospital indicates: hospital name: (b)(6).Surgeon name: dr.(b)(6).Date of initial surgery: (b)(6) 2020.Body part to which device was applied: femur.Surgery description: fracture treatment.Patient information: (b)(6) year-old, male, weight (b)(6) kg., height 175 cm.Problem observed during: into treatment/post operative.Type of problem: device functional problem.Event description: use of external fixator for treatment of femur fracture.Breakage of screw in hydroxyapatite.Need of re-intervention for loss of fracture reduction.The complaint report form also indicates: the device failure had adverse effects on patient: loss of fracture reduction.The initial surgery was not completed with the device.A replacement device was immediately available to complete surgery: intramedullary nail.The event led to an increase in the duration of the surgical procedure of 30 minutes.An additional surgery was required: performed on (b)(6) 2020.A medical intervention (outpatient clinic) was not required.Patient's current health condition: in treatment.Manufacturer reference number: (b)(4).
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Analysis of historical records: orthofix srl checked the internal records related to the controls made on the device code 99-612640, lot b1071830 (lot 25446585 marked on component) before the market release.No anomalies have been found.The original lot, manufactured in 2017, was comprised of (b)(4) devices.All of them have already been distributed to the market.According to orthofix srl historical records, this is the first notification received from this specific device lot.Technical evaluation: the returned device, received on august 6, 2020 was examined by orthofix srl quality engineering department.The device was subjected to visual and dimensional check as per orthofix srl specification.The visual check confirmed the breakage of the screw approx.At the second thread from the stem.The dimensional check did not evidence any anomalies.It was not possible to perform the functional check as the screw is broken.The device was then sent to an external laboratory for the chemical and metallographic analysis, which confirmed the conformity of the screw to material specifications.The fractographic clues, specifically the fracture morphology, indicates a fatigue propagation mechanism.The propagation progressed simultaneously from two opposite directions and with final yield in the central section, indicating a flexural cyclic and alternate load in the direction of propagation of the breakage.The thread section analysis shows secondary cracks.The breakage is likely due to mechanical overload of the screw.Medical evaluation: the information made available on the event with the results of the technical evaluation have been sent to our medical evaluator.Please find below an extract of the medical evaluations performed.August 7th, 2020: the information on this event is very limited.However, certain facts seem clear: 26/6/20: 59 year old male patient, 175 cm and 70 kg, had a femoral fracture treated with external fixation.Details of fixation not supplied.Information suggests that hydroxyapatite coated screws were used.15/7/20: one screw broke then or immediately before.Patient had second operation to insert an i/m nail.Curiously the report states that there was a delay of 30 minutes.This is a short time for removal of external fixation, fracture reduction and i/m nail insertion, so i do not understand what this time refers to.Comment: we need to know the details of the external fixation to understand why a bone screw broke.Was there any suggestion of a second injury or fall to cause this? the normal treatment for a femoral shaft fracture is an intramedullary nail, and often a nail may be inserted 7 or more days after the initial fixation.We do not know what the intentions were here: was the second operation, for an i/m nail, planned anyway? it is possible that the initial treatment was intended as definitive (use of ha coated screws: no point in using them if the fixation is to be removed in 2 - 3 weeks).Above all we need x-rays of the patient with external fixation before and after screw breakage.06 october 2020 with the results of the technical evaluation: this patient was 70 kg and 1.75 m tall, and 59 years old.His bmi is about 23 which is in the middle of the healthy range.We can therefore assume that he is reasonably active.The technical analysis shows clearly that this was a normal bone screw and failed because of excessive cyclic loading leading to fatigue failure.There is much that we do not know about this case to try to understand why this happened.Much would be explained by a single x-ray image.We still need the following information (although i understand that we are not likely to obtain it): how many bone screws were inserted? the reason for this is that in the femur the patient will place a lot of load on the fixator and screws, because the fixator-bone distance is inevitably longer than in the tibia because of the soft tissues.For this reason we recommend 3 screws evenly placed in each screw clamp to spread the load.It is also very important for the position from the fracture to the nearest bone screw to be the same on each side of the fracture, to equalise the lever arm and spread the load evenly.The screw broke 20 days after insertion, at a time when the patient may well be becoming fully mobilised, and therefore carrying more body weight through the frame.If they had been intending to replace the fixation with a nail, almost certainly the nail would have been inserted before day 14, because at this time the risk of infection is low.Longer fixation time increases the risk of infection after secondary nailing.The fact that they used ha coated screws also suggests that this was intended to be definitive fixation, to be kept until healing.What we can be certain of is that this screw failed because it was overloaded.I am suggesting that with an optimum frame design this might not have happened.Breakage of these xcaliber screws is extremely rare, and usually it happens because of particular factors related to the frame design together with the activity of the patient.As i have commented it would be good to know more about the exact details of the fixation.07 october 2020: it is clear that this was a strong frame.It seems likely that because of the frame design one bone screw had more load than the others, so it failed through fatigue.This may have been apparent on looking at the finished frame but it is not possible to make any further comment without a definite idea of how it was put together.Final comments: the results of the technical evaluation concluded that the returned screw was originally conforming to orthofix specification.Based on the results of the technical analysis and medical evaluation, it is possible to presume that the screw broke due to excessive load applied during use, on the chosen configuration of the frame.The fractographic clues, specifically the fracture morphology, indicates a fatigue propagation mechanism.The propagation progressed simultaneously from two opposite directions and with final yield in the central section, indicating a flexural cyclic and alternate load in the direction of propagation of the breakage.The thread section analysis shows secondary cracks.The breakage is likely due to mechanical overload of the screw.Orthofix historical records show that no other notifications have been received in regards to this specific device lot.Orthofix srl continues monitoring the devices on the market.
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The information provided by the hospital indicates: hospital name: (b)(6).Surgeon name: dr.(b)(6).Date of initial surgery: (b)(6) 2020.Body part to which device was applied: femur.Surgery description: fracture treatment.Patient information: 59 year-old, male, weight 70 kg., height 175 cm.Problem observed during: into treatment/post operative.Type of problem: device functional problem.Event description: use of external fixator for treatment of femur fracture.Breakage of screw in hydroxyapatite.Need of re-intervention for loss of fracture reduction.The complaint report form also indicates: the device failure had adverse effects on patient: loss of fracture reduction.The initial surgery was not completed with the device.A replacement device was immediately available to complete surgery: intramedullary nail.The event led to an increase in the duration of the surgical procedure of 30 minutes.An additional surgery was required: performed on (b)(6) 2020.A medical intervention (outpatient clinic) was not required.Copy of operative reports is available (not provided).Copy of x-ray images is available (not provided).Patient's current health condition: in treatment.Information received from the territory manager: on (b)(6) 2020: patient was treated for femur fracture.On (b)(6) 2020: due to the screw breakage, patient underwent a new surgery and the implant was replaced with a nail.Details of external fixation used in june: information not available.Second injury or fall to cause the breakage?: information not available.It is not possible to have copy of x rays.Information received from orthofix srl customer service on october 7, 2020: in the initial surgery they used 6 screws xcaliber osteotite screw l 260/40 mm thread d 6.0-5.6mm code 99-612640.Manufacturer reference number: 2020116.
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