MAUDE Adverse Event Report: STRYKER GMBH GAMMA4 - RC LAG SCREW D10.5X95MM; ROD, FIXATION, INTRAMEDULLARY AND ACCESSORIES

Catalog Number	81660095S
Medical Device Problem Code	Migration (4003)
Health Effect - Clinical Code	Insufficient Information (4580)
Date of Event	01/13/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that the patient who was last operated on (b)(6) 2026, had to undergo revision surgery with u blade.According to the surgeon, the grub screw felt loose during explanation, even though it had been correctly positioned and even locked ¿hand-warm¿ during this surgery on (b)(6) 2026.To the physician, the u-blade (femoral neck screw) also appears to have medialized after revision.The x-ray was provided.The revision was performed on (b)(6) 2026.No further information was provided.
Additional Manufacturer Narrative
Additional information has been requested and if received, will be provided in the supplemental report.
Event or Problem Description
It was reported that the patient who was last operated on (b)(6) 2026, had to undergo revision surgery with u blade.According to the surgeon, the grub screw felt loose during explanation, even though it had been correctly positioned and even locked ¿hand-warm¿ during this surgery on (b)(6).To the physician, the u-blade (femoral neck screw) also appears to have medialized after revision.The x-ray was provided.The revision was performed on (b)(6) 2026.No further information was provided.
Additional Manufacturer Narrative
Correction- d9 updated to from no to return.The reported event of migration could be confirmed, since physical evaluation revealed at the implant surface signs of a migrated lag screw which is also confirmed by the provided x-ray which presents a lag screw medialization.We received the current device together with used nail kit for physical evaluation in already disassembled condition.Detailed inspection revealed signs of migrated lag screw.Furthermore, signs of imprints of the set screw could be verified and also pretty much at the end of the lag screw.Further imprints were found in the base of the flute"[s]" whereas two imprints at lateral presents sliding horizontal scratches to the very lateral end supporting the reported migration.However, both tips of the set screw returned were obviously flattened, indicating contact to a hard metal object.No other signs of damage found on the set screw.For the counterpart nail signs of damage could be verified at lateral entrance of proximal bore hole and signs of damage at the threaded windings and nail reception.Due to the condition not in original condition of the returned device and counterparts primary nail kit used in combi with current device in question, a functional inspection in combi with current lag screw was impossible.Manufacturing and inspection records confirmed the item had been released in accordance with specs.For the returned nail kit itself the set screw could be positioned until its dead-end position within the nail as intended.Therefore, a technical statement about any condition of nail and set screw for this timepoint ,1.Revision treatment, impossible.However, both tips of the set screw returned were flattened, indicating contact to a hard "[metal]" object.No other signs of damage found on the set screw.Finally, based on above and due to details provided it could not be excluded that the set screw was primary not in fully intended position, but an exact root cause could not be verified.Contraindications, warnings and precautions and potential adverse effects are pointed out in the ifu: the operation technique(s) are presented in the appropriate operation technique.The rmf considers that a revision surgery due to medialization or cut out is a typical complication of proximal femoral nailing.This harm does not primly depend on the implant.It is mostly caused by the kind of fracture, patient's general condition, and primly the respective surgical technique.The basics of the gamma-system are the interaction of nail set including a set screw and lag screw in the proximal area.The intention is to allow the fracture site to subside if the fracture gap is too big in order to support bone union.This requires motion in a relative rigid construction and is solved by lateralization of the lag screw.The set screw ¿ as part of the nail kit - is designed to fit into the grooves of the shaft of the lag screw with ascending shapes at both medial and lateral.This prevents both rotation and complete migration of the lag screw but allows sliding in a limited and defined range.The ifu instructs among others-to verify the correct position of the set screw, try to turn the lag screw driver.It is not possible to turn the lag screw driver if the set screw is engaged with the lag screw groove.After tightening the set screw, unscrew the set screw by no more than a quarter of a turn, until a small amount of rotation can be felt at the lag screw driver.This ensures controlled subsidence of the proximal fragment while still preventing medial migration of the lag screw.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 or manufacturing related problems were found during the investigation.With available information a deficiency of the devices in question was not verified.Finally, it was brought to the attention of r&d lifecycle management, engineering.In case substantive information will become available in future that suggests otherwise we reserve the right to reopen the case.

• Brand Name: GAMMA4 - RC LAG SCREW D10.5X95MM
• Common Device Name: ROD, FIXATION, INTRAMEDULLARY AND ACCESSORIES
• Manufacturer (Section D): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; SZ 2545
• Manufacturer (Section G): STRYKER TRAUMA GMBH; prof. kuentscher-strasse 1-5; schoenkirchen/kiel D-242 32; GM D-24232
• Manufacturer Contact: dannielle stap ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 24322774
• Report Number: 0008031020-2026-00157
• Device Sequence Number: 10049754
• Product Code: HSB
• Combination Product (Y/N): N
• Initial Reporter Country: GM
• PMA/510(K) Number: K230512
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2026
• Device Explanted Year: 2026
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 05/26/2026

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?: No
• Operator of Device: Lay User/Patient
• Device Catalogue Number: 81660095S
• Device Lot Number: K1534BC
• Is the Reporter a Health Professional?: Yes
• Was the Report Sent to FDA?: No
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 01/13/2026
• Supplement Date Received by Manufacturer: 04/30/2026
• Initial Report FDA Received Date: 02/12/2026
• Supplement Report FDA Received Date: 05/26/2026
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 11/06/2025
• 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
• Patient Age: 87 YR
• Patient Sex: Unknown