MAUDE Adverse Event Report: SYNTHES (USA); SCREW, FIXATION, BONE

Device Problems Break (1069); Failure to Osseointegrate (1863)

Patient Problems Scarring (2061); Inadequate Osseointegration (2646)

Event Type  Injury  

Manufacturer Narrative

Device was used for treatment, not diagnosis.This report is for an unknown quantity of unknown locking screws.Part and lot numbers were not provided by reporter.The subject device is not expected to be returned to the synthes manufacturer for evaluation.Without a lot number the device history records review could not be completed.The investigation could not be completed; no conclusion could be drawn, as no product was received.If information is obtained that was not available for the initial medwatch, a follow-up medwatch will be filed as appropriate.

Event Description

It was reported that a patient underwent revision surgery due to non-union on (b)(6) 2014.The patient was initially implanted on an unknown date with an unknown synthes plate and unknown synthes locking screws as part of a wrist revision arthrodesis procedure.The patient had prior failed right wrist arthrodesis with persistent nonunion; with significant scarring around the extensor tendons around the bone which was all taken down and there was significant false bony union which was also taken down with rongeur and curet.During the (b)(6) 2014 surgery the existing hardware was explanted.There was solid fusion of the prior wrist arthrodesis everywhere except at the junction of the distal radius and the fuse metacarpal and third metacarpal.This was all taken down to healthy bone and then a new competitor's 7-hole reconstruction plate was implanted with six 4.0 locking screws, placed 3 proximal and 3 distal to the nonunion site.This was augmented with distal radial articular bone graft, vitoss 2.5 ml bone graft, vitoss macro-morsels which were all packed in the defect site.Fixation was secure and verified by x-ray.A jackson-pratt drain was placed.Skin was closed with 4-0 nylon, dressing applied to the wound with plaster reinforcement.This report is for an unknown quantity of unknown locking screws.This report is 2 of 2 for (b)(4).

Manufacturer Narrative

Subject device has been received and is currently in the evaluation process.Investigation is ongoing; no conclusion could be drawn as product is entering the complaint system.Complaint category updated to reflect (2) unknown screw(s) broken-postop.Alert date updated to when synthes became aware of broken screws-postop; issue was identified in the part investigation mar 1, 2016.If information is obtained that was not available for the initial medwatch, a follow-up medwatch will be filed as appropriate.

Manufacturer Narrative

A product investigation was completed: the plate was received intact with noted surface scratches.The eight screw holes each show wear from a mating screw.Based on the wear pattern, a locking screw appears to have been utilized in the first, third and fourth combi holes and cortex screws were used in the remaining holes.The five intact screws were received with wear to the threads and drive recesses consistent with implant and subsequent explant.No issues were identified with the returned plate or intact screws.Three screws were noted to be broken.The cortex screw etched part 402.882/ lot 2394915 shows a transverse break in the middle portion of the threaded shaft (approximately 13.2mm from the proximal screw head surface).The other two screws show roughly transverse breaks in the proximal portion of the threaded shaft.Approximately 22.0mm and 15.5mm of the threaded shafts were received.The threaded heads were not received.On each of the three screws, the threads show wear.The complaint condition is confirmed as the three screws were noted to be broken; the nonunion cannot be confirmed as x-rays were not provided.Replication of the complaint condition is not applicable as the implants are already broken.For the two unknown broken locking screws, the threaded heads were not received and therefore the part numbers could not be definitively determined.However, based on the received portion, it is most probable that they are from the 2.7mm titanium locking screws, self-tapping, with t8 stardrive recess (402.2xx) family.Thus, the documents relating to this screw family were also reviewed.The related product drawings, complaint histories, and risk assessments were reviewed.During the investigation no product design issues or discrepancies were observed that may have contributed to the complaint condition.The returned parts were determined to be suitable for their intended use when employed and maintained as recommended.The breaks are consistent with the result of excessive shear forces.When there is insufficient reduction or healing is delayed there are increased loads the implant must withstand, that would normally be supported by the bone, which could result in metal fatigue.This is further impacted by patience compliance and activity level, comorbidities, and the surgical technique.Thus, as the specific conditions at the time of the breaks are unknown, the root cause cannot be definitively determined.During the investigation no product design issues or discrepancies were observed that may have contributed to the complaint condition.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.

• Type of Device: SCREW, FIXATION, BONE
• Manufacturer (Section D): SYNTHES (USA); 1302 wrights lane east; west chester PA 19380
• Manufacturer Contact: linda plews ; 1302 wrights lane east; west chester, PA 19380 ; 6107195000
• MDR Report Key: 5338322
• MDR Text Key: 34787751
• Report Number: 2520274-2015-18162
• Device Sequence Number: 1
• Product Code: HWC
• Combination Product (y/n): N
• Reporter Country Code: US
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative,health
• Reporter Occupation: Physician
• Type of Report: Initial,Followup,Followup
• Report Date: 03/01/2016

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 12/31/2015
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 02/11/2016
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 03/09/2016
• Was Device Evaluated by Manufacturer?: Yes
• Is the Device Single Use?: Yes
• Type of Device Usage: Unknown
• Patient Sequence Number: 1
• Patient Outcome(s): Required Intervention