MAUDE Adverse Event Report: ZIMMER GMBH DYNESYS, PEDICLE SCREW + SET SCREW, 6.4X50; UNKNOWN

Model Number N/A

Device Problem Defective Device (2588)

Patient Problem No Information (3190)

Event Date 08/24/2016

Event Type  malfunction  

Manufacturer Narrative

The manufacturer did not receive devices, x-rays, or other source documents for review.The actual device reported in section d is not marketed in usa, but devices with similar characteristics (i.E.Dynesys pedikel+stiftschraube 7.2x40; ref# 01.03717.240) are marketed in usa, and therefore this report was filed.Where lot numbers were received for the devices, the device history records were reviewed and found to be conforming.A cause for this specific event cannot be ascertained from the information provided.Should additional information become available and an investigation result be available, an amended medical device report will be submitted.(b)(4).

Event Description

It was reported that a dynesys, pedicle screw + set screw, 6.4x50 should be implanted in a surgery on (b)(6) 2016.It was also reported: "when operation associate open the package found that set screw inside was defected.Subsequently, surgery was completed with another product.The pedicel screw in this complaint was implanted but the set screwnot." the defect set screwwas reported to be shorter than normal products.

Manufacturer Narrative

Trend analysis: no trend identified.Device history records (dhr): the device manufacturing quality records indicate that the released components met all requirements to perform as intended.Event summary: it is reported that the set screw has is shorter than usual.No medical data such as x-rays, surgical notes or any other case-relevant documents received devices analysis: the complained set screw was returned for investigation.The thread and the screw head are deformed.It can be observed that the surface of the screw head is pressed and also the hex drive is partially deformed.The deformations are along the screw axis and can therefore result is a shortening of the set screw.The set screw was measured: specifications: 6.8 - 7.2; measured: 5.80; the deformed screw is out of specifications.Review of product documentation: inspection plan of the device was reviewed: the characteristic feature number 6: length ¿7¿ was checked for quantitative examination with aql 2.5.The inspection plan states also that the characteristic feature number 1: "n7 (ra 1.6)" as well as the characteristic feature number 2: "break all edges" are checked by the supplier.For the characteristic feature number 2: "break all edges" the inspection performed by the supplier is 100% visual under the microscope.A complaint search was performed with the three reference numbers of the set screw (b)(4).The search did not reveal any reported event similar to set screw damaged in the package/too short/out of specification/dimension.The search revealed a total of 10 complaints (since the existence of the database) reporting difficulties in inserting the set screw in the pedicle screw and/or stripping of the set screw during surgery.The 10 reported issues occurred in the time frame between 2002 and 2016.The set screw drawing was reviewed.This drawing is valid for all dynesys set screws which have following ref.Numbers: (b)(4).The dhr documents of the set screw as well as the corresponding purchase order from supplier were reviewed.All device manufacturing quality records indicate that the released components met all requirements to perform as intended.Additionally, the results of the incoming inspection were reviewed.The incoming inspection charge was inspected on 14.03.2014.(b)(4) set screws (out of (b)(4)) were inspected according to inspection plan for the length (7mm +/- 0.2) and were found to be all within specification.Root cause analysis: the returned screw was visually inspected and measured during investigation.The set screw was found to be 1mm too short (5.80 mm).The visual examination showed that the returned screw is heavily deformed.The deformations are along the screw axis, which result in a shortening of the set screw, as well as at the thread.The reasons for the deformation/damage of the set screw are unknown.Two scenarios are possible: the set screw was packaged already deformed.The set screw was damaged during handling/implantation (after opening of the package).With regards to the fist scenario: the set screw was packaged already deformed: all device manufacturing quality records (dhr, order, inspection plan, incoming inspection results) were reviewed as well as a complaint search for similar events was performed.All the documents indicate that the released components met all requirements to perform as intended.According to the inspection plan, the inspection performed by the supplier for the characteristic feature number 2: "break all edges" is a 100% visual inspection under the microscope.The "(b)(4)" of the supplier confirms, that the products were produced and checked according to the order and therefore according the above-mentioned inspection plan.For this reason it is highly unlikely that a deformed set screw, as the one returned for investigation in this complaint, would have been released to the market.Additionally, the complaint search did not reveal any reported event similar to set screw damaged in the package/too short/out of specification/dimension.With regards to the second scenario: the set screw was damaged during handling/implantation (after opening of the package): the returned screw is heavily deformed, which results in screw shortening.The thread of the screw is also damaged.A damage on an implant can result by application of high forces during handling and/or implantation.The complaint search highlighted that difficulties in inserting the set screw in the pedicle screw and/or stripping of the set screw already happened during surgery in the past.These complaints could not be confirmed as no product was returned or the investigation suggest use error of the device.The damages of the thread typically arise if the screw is set at an angle and then tried to be screwed-in against the resistance resulting from a slanted setting.It is important for the threaded pin to pass through the first and second revolution without resistance.If there is a noticeable resistance after a half or a whole revolution after setting and screwing-in the threaded pin, it has been placed at a slant and has to be unscrewed again.Resetting is possible, if it does not show any damages.A damaged set screw must not be used anymore and has to be replaced by a new one.Within the operative field, the required lateral screw setting technique can make the screw alignment to the pedicle screw axis difficult due to the surrounding soft tissue.Possibly, a decompression of the soft tissue is required to allow the correct setting of the set screw.The damage of implant or incorrect implant positioning is also listed as risk in the dfmea of the set screw: damaged implant.Incorrect implant positioning.Due to handling difficulties during surgery.Incorrect connection between implant and instruments => possible: the returned set screw is deformed.Conclusion summary: the returned screw is deformed.The deformations along the screw axis can result in a shortening of the set screw.The reasons for the deformation/damage of the set screw are unknown.Two possible scenarios are possible: the set screw was packaged already deformed.The set screw was damaged during handling/implantation (after opening of the package) the investigation shows that the first scenario is highly unlikely and that the second scenario is more plausible.However, based on the available information it is impossible to determine an exact root cause for the reported issue.The need for corrective measures is not indicated and zimmer (b)(4) considers this case as closed.(b)(4).

• Brand Name: DYNESYS, PEDICLE SCREW + SET SCREW, 6.4X50
• Type of Device: UNKNOWN
• Manufacturer (Section D): ZIMMER GMBH; sulzer allee 8; sulzer industrie park; winterthur 8404 ; SZ 8404
• Manufacturer (Section G): ZIMMER GMBH; sulzer allee 8; sulzer industrie park; winterthur 8404 ; SZ 8404
• Manufacturer Contact: kevin escapule ; 1800 west center street; warsaw, IN 46580 ; 8006136131
• MDR Report Key: 5952572
• MDR Text Key: 55160343
• Report Number: 0009613350-2016-01206
• Device Sequence Number: 1
• Product Code: HXB
• Combination Product (y/n): N
• Reporter Country Code: CH
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: foreign,health professional
• Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date: 08/24/2016

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 09/15/2016
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Expiration Date: 03/31/2019
• Device Model Number: N/A
• Device Catalogue Number: 01.03764.050
• Device Lot Number: 2755213
• Other Device ID Number: 00889024426689
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 11/30/2016
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 12/01/2016
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 04/01/2014
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Removal/Correction Number: N/A
• Patient Sequence Number: 1