MAUDE Adverse Event Report: ALPHATEC SPINE INC 5.5MM UNIPLANAR SCREW, 40MM (TI-6AL-4V); KWP, MNH, MNI

Model Number 22055-40

Device Problems Break (1069); Disassembly (1168)

Patient Problem No Consequences Or Impact To Patient (2199)

Event Date 09/08/2015

Event Type  malfunction  

Manufacturer Narrative

A review of the device history records revealed no irregularities.The implants were found to be properly manufactured and released in accordance with the device master record.Visual inspection did not find that the screw was dis-assembled as reported but rather the internal bushing become misaligned/twisted.Additionally, one side of the head/tulip was slightly cracked and bent outwards but remained secured to the implant.This indicates the axial reducer may not have been completely attached and when forces were placed to the screw during the derotation maneuver.The purpose of the uniplanar screw is to restrict motion in the axial plane so the surgeon can manipulate the vertebral column to correct axial deformity.To restrict axial motion, the uniplanar screw was designed with flats on the normally spherical head of the pedicle screw.The uniplanar screw bushing has features which mate with the flat sides of the pedicle screw.The outcome of this design is that the uniplanar screw acts like a fixed screw.To adjust the rotational position of the uniplanar screw the pedicle screw must rotate.In certain instances the friction between the screw head and bushing can be overcome, and rotation of the head does not result in the simultaneous rotation of the bone screw and bushing.This results in misalignment which will prevent the rod from fully engaging the screw.This issue can be minimized when proper technique and instruments are used.Field bulletin (b)(4) provides instructions for in situ realignment.Do not remove the screw.It can be realigned use the following instruments from the zodiac instrument set: screw removal shaft · rod rocker 1.Engage the inner hex of the uniplanar screw with the screw removal shaft.You will use the screw removal shaft as an anti-torque to prevent the screw from advancing into the pedicle while realigning the bushing and tulip.2.Use the rod rocker to engage the tulip of the uniplanar screw.3.Rotate the screw head with the rocker to realign the tulip with the bushing.· use the head positioner to realign the screw head so the rod may be inserted.The zodiac spinal fixation system is intended for use as a posterior spinal fixation device to aid in the surgical correction of various spinal deformities and pathologies of the spine.It is intended to provide stabilization during the development of fusion utilizing a bone graft.Specific indications for the zodiac system are dependent in part on the configuration of the assembled device and the method of attachment to the spine.

Event Description

An international customer ((b)(6)) report that during the use of the dvr de-rotation set, the surgeon experienced disassembly of shaft and tulip of the uniplanar screw.It was also reported that the head/tulip had broken during the process.The event caused the patient no ill effect.

• Brand Name: 5.5MM UNIPLANAR SCREW, 40MM (TI-6AL-4V)
• Type of Device: KWP, MNH, MNI
• Manufacturer (Section D): ALPHATEC SPINE INC; 5818 el camino real; carlsbad CA 92008
• Manufacturer Contact: vernon trimble ; 5818 el camino real; carlsbad, CA 92008 ; 7604946648
• MDR Report Key: 5131010
• MDR Text Key: 27936184
• Report Number: 2027467-2015-00183
• Device Sequence Number: 1
• Product Code: KWP
• Combination Product (y/n): N
• Reporter Country Code: IT
• PMA/PMN Number: K100685
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative,foreig
• Reporter Occupation: Other
• Report Date: 09/10/2015

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 10/06/2015
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Physician
• Device Model Number: 22055-40
• Device Catalogue Number: 22055-40
• Device Lot Number: 637070
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 09/21/2015
• Is the Reporter a Health Professional?: No
• Date Manufacturer Received: 09/10/2015
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 12/02/2010
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: N
• Patient Sequence Number: 1
• Patient Outcome(s): Other
• Patient Age: 16 YR