MAUDE Adverse Event Report: LIMACORPORATE SPA BONE SCREW Ø6,5 H.35MM

Model Number 8420.15.040

Device Problems Break (1069); Difficult to Remove (1528)

Patient Problem Foreign Body In Patient (2687)

Event Date 05/07/2021

Event Type  malfunction  

Manufacturer Narrative

By checking the manufacturing charts of lot #2101696, no anomalies were detected on the products manufactured with the same lot #.This is the first and only complaint received on this lot #.We will submit a final mdr once the investigation will be completed.

Event Description

During hip surgery performed on (b)(6) 2021, the head of the bone screw ø6,5 h.35mm (product code 8420.15.040, lot# 2101696 - ster.2100048) broke.The screw was being inserted into the acetabulum while implanting a delta tt acetabular cup.According to the reported information, difficulty in inserting the screw was experienced.It was reported that the rest of the screw was left on the patient.Surgery prolonged of 20 minutes.Event happened in (b)(6).

Manufacturer Narrative

Check of the device history records by the check of the manufacturing charts of the screws with lot 2101696, no pre-existing anomalies were detected, therefore we can state they had been manufactured up to drawings specifications and in line with relevant tests and checks.According to our records, 143 screws with lot number 2101696 have already been implanted (out of 200 manufactured) and this is the first and only complaint received on this lot number.X-rays analysis post-operative x-rays and a photo of the broken screw head were shared with limacorporate and analyzed by a medical consultant, he commented: "looking at the x-ray you clearly can identify the hole for the screw being not in the direction of the screw fragment.I conclude that the surgeon has initially placed the drill eccentrically, without using the respective drill guide.When inserting the screw it such was not possible to place the whole head inside the respective deepening of the cup.Most likely the surgeon tried to force the head into the deepening by forcibly screwing, such breaking the head.It is unlikely, that the remaining fragment can cause any damage in the future and such believe the surgeon was right when leaving it as it is.Personally i believe the surgeon not being very experienced, as the implanted stem also is not in a perfect position.In summary the result appears acceptable." test performed the involved screw remained implanted, while the screw head was removed, however, the screw head was not returned to limacorporate for analysis.To further investigate the reported incident, limacorporate decided to perform some analyses on screws of the specific lot number involved as well as on other lot numbers of the same product code (8420.15.040).Specifically, the following investigation were performed: - dimensional analysis to confirm the absence of dimensional anomalies that could have contributed to the breakage occurred, - analysis on the torsional properties of the screws according to astm f543-17 - standard specification and test methods for metallic medical bone screws (this analysis was outsourced to an external laboratory).Nine screws belonging to product code 8420.15.040 (35mm length), available in internal warehouses, were therefore used for the analyses.Among these screws, three belong to the lot number involved in this complaint (2101696).Dimensional analysis: the relevant measures of all the above-mentioned screws were within the expected tolerances, no deviation was detected.Torsional properties analysis: all the bone screws were found to be compliant to the minimum acceptable values reported on astm f543-17: no deformation nor breakage appeared on the tested screws.The screws resisted a torque loading of at least 6.2 nm and a rotation angle of 90° with no deformation nor breakage.The torsional strength according to astm f543-17 resulted (10.77 ± 0.46) nm.The torsional analysis of the screws was stopped at the minimal requirements according to astm f543-17 as testing until breakage could not have been completed due to limits of the screwdrivers (breakage/deformation).Conclusion and pms data based on the analyses performed, we can state that: - the check of the manufacturing charts highlighted no pre-existing anomalies on the total number of bone screws manufactured with lot 2101696, - no dimensional anomaly was detected on the screws that belong to the same lot number (2101696) available at internal warehouses, - the torsional properties of the tested bone screws belonging to code 8420.15.040 (including three screws with lot the same lot number of the one involved in this complaint: 2101696) resulted compliant to the astm f543-17; in conclusion, the cause of the reported breakage cannot be determined with certainty, however we might speculate that an intra-operative error while inserting the screw contributed to the incident.Perhaps, a misalignment of the screwdriver led to an incorrect transmission of loads to the screw head, the non-axial application of the torque might have then caused an unproper stress to the screw head, ultimately causing its breakage.Another possible explanation is suggested by the x-rays analysis: our medical expert hypothesized a possible intra-operative scenario that might have contributed to the reported breakage, which would be linked to a suboptimal preparation of the screw hole with the drill and consequent excessive force application to complete the screw insertion.According to limacorporate pms data, we can estimate the intra-operative breakage of bone screws - belonging to the family codes 8420.15.Xxx - to be < 0,001%.Based on the root cause analysis performed and according to the relevant pms data, no corrective actions required for this specific case.Limacorporate will continue monitoring the market to promptly detect any further similar issue.

Event Description

During hip surgery performed on (b)(6) 2021, the head of the bone screw ø6,5 h.35mm (product code 8420.15.040, lot 2101696 - ster.2100048) broke.The screw was being inserted into the acetabulum while implanting a delta tt acetabular cup.According to the reported information, difficulty in inserting the screw was experienced.It was reported that the rest of the screw was left in the patient.The surgery was prolonged of 20 minutes due to this issue.This event occurred in (b)(6).

• Brand Name: BONE SCREW Ø6,5 H.35MM
• Type of Device: BONE SCREW Ø6,5 H.35MM
• Manufacturer (Section D): LIMACORPORATE SPA; via nazionale 52; villanova di san daniele, udine 33038 ; IT 33038
• Manufacturer Contact: via nazionale 52; villanova di san daniele, udine 33038
• MDR Report Key: 12007720
• MDR Text Key: 266409076
• Report Number: 3008021110-2021-00042
• Device Sequence Number: 1
• Product Code: LPH
• Combination Product (y/n): N
• PMA/PMN Number: K172456
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Other
• Reporter Occupation: Other
• Type of Report: Initial,Followup

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Model Number: 8420.15.040
• Device Lot Number: 2101696
• Is the Reporter a Health Professional?: No
• Initial Date Manufacturer Received: Not provided
• Initial Date FDA Received: 06/16/2021
• Supplement Dates Manufacturer Received: Not provided
• Supplement Dates FDA Received: 08/04/2022
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1
• Patient Outcome(s): Other; Hospitalization