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The information initially provided by the local distributor indicates: - product code: 1 ss10621 lot g012 (broke) and 1 ss10621 lot g013 (bent).- hospital name: (b)(6).- surgeon's name: dr.(b)(6).- date of surgery: (b)(6) 2020.- body part to which device was applied: femur condylar fracture.- surgery description: fracture treatment.- patient information: (b)(6) year-old, male.- problem observed during: clinical use on patient/intraoperative.- type of problem: device functional problem.- event description: "the surgeon had applied the plate to a femoral fracture.The external fixator was intended to be used temporarily for bone traction.Our sales representative told the surgeon in advance that using a 4.5mm diameter screw on an adult man was too thin.The broken piece remains in the patient's body.We heard that the broken pieces will be removed together with the plate removal surgery.The complaint report form also indicates: - the device failure had adverse effects on patient.- the initial surgery was not completed with the device.- a replacement device of the same model was not immediately available to complete surgery: the external fixator was to be used for traction during plate surgery.After the screw broke, it was pulled manually as usual.- the event did not lead to a clinically relevant increase in the duration of the surgical procedure.- an additional surgery was not required.- copies of the operative reports are not available.- copies of the x-ray images are not available.- patient current health condition: there is no problem with the patient's current health condition.(b)(4).
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The information initially provided by the local distributor indicates: - product code: 1 ss10621 lot g012 (broke) and 1 ss10621 lot g013 (bent) - hospital name: (b)(6) hospital.- surgeon's name: dr.(b)(6).- date of surgery: (b)(6) 2020.- body part to which device was applied: femur condylar fracture - surgery description: fracture treatment.- patient information: 48 year-old, male.- problem observed during: clinical use on patient/intraoperative - type of problem: device functional problem.- event description: "the surgeon had applied the plate to a femoral fracture.The external fixator was intended to be used temporarily for bone traction.Our sales representative told the surgeon in advance that using a 4.5mm diameter screw on an adult man was too thin.The broken piece remains in the patient's body.We heard that the broken pieces will be removed together with the plate removal surgery.The complaint report form also indicates: - the device failure had adverse effects on patient - the initial surgery was not completed with the device - a replacement device of the same model was not immediately available to complete surgery: the external fixator was to be used for traction during plate surgery.After the screw broke, it was pulled manually as usual.- the event did not lead to a clinically relevant increase in the duration of the surgical procedure - an additional surgery was not required - copies of the operative reports are not available - copies of the x-ray images are not available - patient current health condition: there is no problem with the patient's current health condition.Manufacturer ref: (b)(4).Distributor ref: (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 ss10621 lot g012 before the market release.No anomalies have been found.The original lot, manufactured in 2018, was comprised of (b)(4) units.All of them have already been distributed to the market.According to orthofix srl historical records, no other notifications have been received for this specific device lot.-orthofix srl checked the internal records related to the controls made on the device code ss10621 lot g013 before the market release.No anomalies have been found.The original lot, manufactured in 2018, was comprised of (b)(4) units.All of them have already been distributed to the market.According to orthofix srl historical records, no other notifications have been received for this specific device lot.Technical evaluation the returned devices, received on 25th may 2020, were examined by orthofix srl quality engineering department.The devices were subjected to visual and dimensional check as per orthofix srl specifications.The visual check confirmed the problem notified.Screw lot g012 is broken, while screw lot g013 is bent.The dimensional check, performed where possible, did not evidence any anomalies.The verification of the raw material of the returned devices performed by an external laboratory confirmed that the material is conforming to orthofix srl specifications.Medical evaluation.The information made available on the event together with the results of the technical evaluation were sent to our medical evaluator.Please find below an extract of the medical evaluations performed.-(b)(6) 2020.This case involves the use of two small series screws, which are identical to the standard range of screws but have a longer thread: size 140/50, with thread length 50 mm and total length 140 mm; shank 6.0 mm and thread diameter tapered from 4.5 mm to 3.5 mm.These screws are designed for use in paediatric applications or in small bones in adults, normally in the upper limb.In this case a 48 year old male patient was being treated for a distal femoral fracture.The surgeon wanted to apply temporary external fixation intra-operatively to establish a good reduction of the fracture so that a plate could be applied to hold the position.These screws were used for the external fixation.The case demonstrates very well that these screws are not suitable for this application, as one bent and one broke.The screws bent or broke near the middle of the thread length; this suggests that the thread was only half inserted into the bone, as breakage when it does occur happens at the point of maximum loading which in this case will be the junction with the cortical bone.The retained piece of screw will be removed when the plate is removed after bone healing.The patient will come to no harm at all from this screw fragment.I am quite certain that these screws were loaded beyond their design criteria, and broke because they were overloaded.These screws are not suitable for use in the adult femur, even temporarily.-7th july 2020 with the results of the technical analysis this report confirms that the material of these bone screws was fully to specification.The following facts can be stated about this case: 1.The surgeon was using 2 bone screws to hold a distal femoral fracture in a 48 year old male patient temporarily in position using external fixation while applying definitive fixation in the form of a plate.2.These 2 bone screws were 140/50 in size, meaning that there is 50 mm of thread on the screw, the thread being tapered from 4.5 mm to 3.5 mm 3.This size of screw is definitely not indicated for use in an adult male patient, even if temporarily.They are not strong enough.4.It is clear from the position of the screw breaking or bending that they were only inserted about halfway into the bone.When they do break these screws do so at the junction with the bone surface, which will be the position of the maximum bending or torsional load.5.The technical analysis states that the screws failed because of an acute torsional load.6.The technical analysis confirms our previous conclusion that these screws were overloaded because they were used in an inappropriate position and patient 7.Looking at a similar bone screw that i have with me, i see that the core diameter at the mid-point of the thread in this size of screw is close to 3.0 mm.This is not enough to withstand the types of loads that will be present during the fixation of an adult femur.8.I agree with the conclusion that these screws failed because they were loaded beyond their design criteria.Final comments the results of the technical evaluation concluded that the two returned screws were originally conforming to orthofix specifications.According to the information provided on the case and as a result of the investigation performed, orthofix srl can conclude that the screws were subjected to torsional overload during insertion which caused it to break.The breakage is related to the inadequate screw size selected for the required application on an adult femur.Orthofix srl would like to remind the importance of following the instructions for use (orthofix® bone screws for external fixation system, ref.Pq scr), where detailed information are reported regarding screw selection.Based on the results of the technical evaluation, and on the evidences deriving from the medical evaluation, orthofix srl can conclude that the problem that occurred is not device related.The analysis of the historical data evidenced that no other notifications have been received on devices belonging to the same lot.Orthofix continues monitoring the products on the market.Please also kindly refer to mfr report 9680825-2020-00036 follow up 1.
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