MAUDE Adverse Event Report: SYNTHES GMBH UNK - MONO/POLYAXIAL SCREWS: SYNAPSE; POSTERIOR CERVICAL SCREW SYSTEM

Device Problem Mechanical Problem (1384)

Patient Problem Physical Asymmetry (4573)

Event Type  Injury  

Event Description

This report is being filed after the review of the following journal article: shimizu t, et al (2022), paravertebral foramen screw fixation for posterior cervical spine surgery: clinical case series, j neurosurgeon spine, volume 36, pages 479-486, doi: 10.3171/2021.6.Spine21411 (japan).The goal of this study was to clarify the clinical utility of paravertebral foramen screws and to determine intraoperative indicators for appropriate screw placement during posterior cervical fusion surgery to improve its safety.Between january 2016 and february 2020 46 patients who underwent posterior cervical spine surgery with 94 paravertebral foramen screws were included in the study.There were 29 men and 17 women with a mean age at the time of surgery of 61.6 years (range 35¿89 years).The 94 paravertebral foramen screws were divided into 3 groups as follows: 25 were classified as being in the longer group, 43 were classified as being in the intermediate group, and 26 were classified as being in the shorter group according to cervical lateral radiographic views.In the longer group, the tip of paravertebral foramen screws was located anteriorly from the line of the posterior wall of the vertebral body (> +0 mm); in the intermediate group, the screw tip was located up to 2 mm posteriorly to the posterior wall of the vertebral body (¿2 to 0 mm); and in the shorter group, the screw tip was located more than 2 mm posteriorly (< ¿2 mm).The synthes 4.5 mm synapse screws were used in all the patients in the study.The mean follow-up period was 31.1 months (range 12¿56 months).Complications were reported as follows: 14 screws were classified as having an inappropriate position, 9 penetrated a vertebral foramen, and 5 penetrated a transverse foramen.A (b)(6) woman had the screw inserted in c6 unilaterally showed loosening, but it did not cause clinical symptoms or implant failure.This was confirmed on cervical radiography 1 year after surgery.A (b)(6) woman had screws on both sides in c3 had pulled out and the reduction at the atlantoaxial joint had been lost as shown on cervical radiography obtained at 1 week after surgery.Revision surgery was performed by removing c3 screws and extending the caudal level of fusion to t1.This report is for the unknown synthes 4.5 mm synapse screws.A copy of the clinical evaluation form is being submitted with this regulatory report.This is report 1 of 4 for (b)(4) and captures ¿a (b)(6) woman had screws on both sides in c3 had pulled out and the reduction at the atlantoaxial joint had been lost as shown on cervical radiography obtained at 1 week after surgery.Revision surgery was performed by removing c3 screws and extending the caudal level of fusion to t1.¿.

Manufacturer Narrative

Brand name, common device name, manufacturer name, city, and state, lot #, pma/510k: this report is for an unknown 4.5 mm synapse screw/unknown lot.Part and lot number are unknown; udi number is unknown.Device available for evaluation: complainant part is not expected to be returned for manufacturer review/investigation.Device evaluated by mfr and manufacture date: without a lot number the device history records review could not be completed.Product was not returned.Based on the information available, it has been determined that no corrective and/or preventative action is proposed.This complaint will be accounted for and monitored via post market surveillance activities.If additional information is made available, the investigation will be updated as applicable.Device was used for treatment, not diagnosis.If information is obtained that was not available for the initial medwatch, a follow-up medwatch will be filed as appropriate.

• Brand Name: UNK - MONO/POLYAXIAL SCREWS: SYNAPSE
• Type of Device: POSTERIOR CERVICAL SCREW SYSTEM
• Manufacturer (Section D): SYNTHES GMBH; eimattstrasse 3; oberdorf 4436 ; SZ 4436
• Manufacturer Contact: kate karberg ; 1302 wright lane east; west chester, PA 19380 ; 3035526892
• MDR Report Key: 14466652
• MDR Text Key: 293632470
• Report Number: 8030965-2022-03383
• Device Sequence Number: 1
• Product Code: NKG
• Combination Product (y/n): N
• Reporter Country Code: JA
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Foreign,Literature
• Reporter Occupation: Other Health Care Professional
• Type of Report: Initial

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 05/21/2022
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 04/22/2022
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Is the Device Single Use?: Yes
• Type of Device Usage: Unknown
• Patient Sequence Number: 1
• Patient Outcome(s): Required Intervention
• Patient Age: 78 YR
• Patient Sex: Female