MAUDE Adverse Event Report: MEDACTA INTERNATIONAL SA MUST PEDICLE SCREW 6X45

Catalog Number 03.50.018

Device Problems Fracture (1260); Noise, Audible (3273)

Patient Problem No Known Impact Or Consequence To Patient (2692)

Event Date 06/14/2016

Event Type  Injury  

Manufacturer Narrative

On 16 june 2016 the r&d director commented the case: the instrument is not involved.It seems that the failure is caused by cross-threading which can happen in very rare cases.Batch review performed on 11 july 2016.(b)(4).On 14 july 2016 the r&d project manger made the following analysis of the case: potential cross threading of the setscrew (wrong engagement of the thread), might have resulted in damage of the setscrew during final tightening.Cross threading is a rare event that can occur with every pedicle screw system.Instruments are provided in the set to ensure the correct alignment and engagement of the setscrew.The surgeon is usually able to notice if cross threading occurred, and in such case he can remove and reposition the setscrew in the pedicle screw.In this case, the surgeon mentioned that he "felt cross thread might be occurred" but he continued.Even in case of cross threading and subsequent tightening, damaging the setscrew and/or to the pedicle screw head is very unlikely.Internal tests have been performed to reproduce such event (cross threading+final tightening) and in no case a breakage of the setsrcrew similar to the pictures reported with this complaint occurred.The batch record of this production lot, including the batch record of the semi-finished components, was reviewed: no anomalies found.Already (b)(4) implants of the same production lot (157843) and total (b)(4) implants including a setscrew from the same semi-finished production lot have been implanted so far, without any reported issue.Therefore a production defect can be excluded.Events of thread breakage as presented in the complaint, might be related to a different manoeuvres, such as hammering of the setscrew against the tulip.Not yet received.

Event Description

Since the surgeon felt some abnormal click-noise during tightening the set screw with the torque driver, he removed the set screw.At that time he found metalic piece.It was unknown, but either the set screw or the pedicle screw might be fractured due to cross thread.

Manufacturer Narrative

Visual inspection performed on july, the 29th 2016 by the (b)(4) project manager: the set screw is severely damaged with a neat breakage of two threads.The thread of the pedicle screw head is damaged as well correspondingly.As discussed in the preliminary investigation, it is very unlikely that a cross threading caused similar damage.Moreover the damage looks very localized to a specific area of two thread.Most likely, the damage or breakage occurred during an unintended manoeuvre such as hammering on the set-screw-driver, or tentative to apply a bending (leverage) by means of the set-screw-driver on the set-screw partially engaged.

• Brand Name: MUST PEDICLE SCREW 6X45
• Type of Device: PEDICLE SCREW
• Manufacturer (Section D): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, 6874 ; SZ 6874
• Manufacturer (Section G): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, 6874 ; SZ 6874
• Manufacturer Contact: stefano baj ; strada regina; castel san pietro, 6874 ; SZ 6874 ; 91 6966060
• MDR Report Key: 5793843
• MDR Text Key: 49517407
• Report Number: 3005180920-2016-00346
• Device Sequence Number: 1
• Product Code: MNI
• Combination Product (y/n): N
• Reporter Country Code: JA
• PMA/PMN Number: K121115
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative
• Reporter Occupation: Other
• Type of Report: Initial,Followup
• Report Date: 08/03/2016

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 07/14/2016
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Expiration Date: 01/13/2021
• Device Catalogue Number: 03.50.018
• Device Lot Number: 157843
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 07/22/2016
• Is the Reporter a Health Professional?: No
• Date Manufacturer Received: 06/14/2016
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 02/01/2016
• 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
• Patient Age: 57 YR