MAUDE Adverse Event Report: STRYKER GMBH 6.5MM CENTER SCREW - 36M M; PROSTHESIS, SHOULDER, SEMI-CONSTRAINED, METAL/POLYMER CEMENTED

Model Number	5573-6536
Medical Device Problem Codes	Break (1069); Fracture (1260)
Health Effect - Clinical Code	Failure of Implant (1924)
Date of Event	01/18/2022
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
Upon completion of the investigation, additional information will be provided in a supplemental report.
Event or Problem Description
"it was reported that the patient's right shoulder was revised due to a broken peripheral and center screw in the baseplate.All devices except for the stem were revised.The cup was revised in order to access the glenosphere and because the surgeon wanted to implant thicker implants.".
Additional Manufacturer Narrative
The reported event could be confirmed, since the screw is broken as complained.The device inspection revealed the following: the visual inspection has shown that the screw is broken apart, the fragment with a length of about 4.5 mm was not returned for evaluation.The screw head with the locking thread is intact, the are no signs for an excessive contact between the screw head and the baseplate.More than half of the fracture face is not visible anymore, the shiny surface indicates that the fracture faces did rub against each other for a longer period of time.The rest of the fracture face has the typical view of a fatigue fracture with an uniform fine-grained texture.The complaint was forwarded to the r&d department for evaluation with following result: the baseplate was most likely implanted using an improper technique.It appears that some of the screw holes may have been damaged by being drilled off-axis, distorting the circular geometry of the locking rib and therefore not allowing the screws to become fully locked into the baseplate rib.Evidence can be seen in the images of both the baseplate and the underside of the glenosphere.When properly installed in the baseplate, the screws will not migrate from their locked positions.There are other circumstances that may cause this scenario such as using power to drive the screws all the way down, improper use of the drill guide, etc." the relevant dimensions of the screw were verified during the investigation and no deviation from the specification could be detected.A review of the device history for the reported lot did not indicate any abnormalities.No corrective actions are required at this time.A review of the labeling did not indicate any abnormalities.No indications of material, manufacturing or design related problems were found during the investigation.Based on investigation, the root cause was attributed to a user related issue.The failure was most likely caused by an improper implantation of the baseplate, this did lead to a damage of the locking holes and therefore the locking threads of the screws could not be locked in the baseplate as required.Due to that the fixation of the screws was unstable and the force was not distributed as designed which finally caused a fatigue failure of the screws.If more information is provided, the case will be reassessed.
Event or Problem Description
"it was reported that the patient's right shoulder was revised due to a broken peripheral and center screw in the baseplate.All devices except for the stem were revised.The cup was revised in order to access the glenosphere and because the surgeon wanted to implant thicker implants.".

• Brand Name: 6.5MM CENTER SCREW - 36M M
• Common Device Name: PROSTHESIS, SHOULDER, SEMI-CONSTRAINED, METAL/POLYMER CEMENTED
• Manufacturer (Section D): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; SZ 2545
• Manufacturer (Section G): STRYKER ORTHOPAEDICS-MAHWAH; 325 corporate drive; mahwah NJ 07430
• Manufacturer Contact: anna jusinski ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 13518623
• Report Number: 0008031020-2022-00049
• Device Sequence Number: 4158651
• Product Code: KWS
• UDI-Device Identifier: 07613327098846
• UDI-Public: 07613327098846
• Combination Product (Y/N): N
• Initial Reporter State: PA
• Initial Reporter Country: US
• PMA/510(K) Number: K130895
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2018
• Device Explanted Year: 2022
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 06/03/2022

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Operator of Device: Lay User/Patient
• Device Expiration Date: 02/28/2023
• Device Model Number: 5573-6536
• Device Catalogue Number: 5573-6536
• Device Lot Number: X178YT
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 02/10/2022
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 01/18/2022
• Supplement Date Received by Manufacturer: 05/04/2022
• Initial Report FDA Received Date: 02/11/2022
• Supplement Report FDA Received Date: 06/03/2022
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 02/13/2018
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention; Hospitalization
• Patient Age: 68 YR
• Patient Sex: Male