MAUDE Adverse Event Report: STRYKER ORTHOPAEDICS-MAHWAH TRIDENT PSL HA CLUSTER 52MM; PROSTHESIS, HIP, SEMI-CONSTRAINED, METAL/POLYMER, POROUS UNCEMENTED

Catalog Number	542-11-52E
Medical Device Problem Codes	Malposition of Device (2616); Positioning Problem (3009)
Health Effect - Clinical Codes	Pain (1994); Injury (2348)
Date of Event	05/11/2017
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
The reported dislocation was confirmed.Medical review determined the primary cause of this event is due to cup malposition.The cup was not returned for evaluation.-medical records received and evaluation: a review of the provided x-rays by a clinical consultant noted the following; the principal problem of this case is cup malposition leading to an intraprosthetic dislocation requiring revision within 4-weeks of implantation.Total hip components require positioning for optimal rom.Normal cup position is around 45° of inclination (abduction) and some 20° of anteversion, a bit depending upon approach to the hip and surgeon preference.The stem should have an anteversion around 15°, again depending upon surgical approach and stem design.In this case, the cup has a very high inclination of 60° where 40° - 45° would be the target for optimal inclination.Furthermore, the cup does have virtually no anteversion where normal range should be within 15° - 25° of anteversion.Lack of cup anteversion is evident from the straight line projection of the cup opening circle on the ap view.Principal root cause of failure thus was cup malposition leading to impingement and intraprosthetic dislocation.Because cup position was the principal problem and the surgeon is responsible for optimal component placement, principal root cause of failure is procedure-related with the instability further aggravated by another procedure-related effect related to early postoperative muscular laxity.Also the incomplete seating of the metal insert is a procedure-related factor.- no evidence is available to suggest that device-related factors might have played a role while the present failure scenario as based upon an adverse mix of several procedure related factors provides a plausible explanation for the failure event of this case consistent with all reported facts and findings.This event is not device-related.Procedure-related factors: - cup malposition in very high inclination, absent anteversion and superficial position - incomplete mdm metal liner seating a non-related issue.Patient-related factors - none.Device-related factors: - none.Diagnosis: - cup malposition in steep inclination, absent anteversion and superficial position has contributed to instability in the arthroplasty leading to early dislocation within 4-weeks of implantation, a timeframe with still incomplete healing of soft tissue structures of the hip.The use of an adm cup insert resulted in an intraprosthetic dislocation requiring revision." -device history review: device history review indicated the devices accepted into final stock from the reported lot were free from discrepancies.-complaint history review: there has been no other event for the lot referenced.Conclusions: a review of the provided x-rays by a clinical consultant concluded "cup malposition in steep inclination, absent anteversion and superficial position has contributed to instability in the arthroplasty leading to early dislocation within 4-weeks of implantation, a timeframe with still incomplete healing of soft tissue structures of the hip.The use of an adm cup insert resulted in an intraprosthetic dislocation requiring revision.".
Event or Problem Description
After a surgery performed on (b)(6) 2017, which was about a complete hip prosthesis thelios and which completed successfully, the patient came back to the hospital in emergency one month later because she had pain.It appeared that the patient suffers from a dislocation: the head of the implant came out of the insert.Then the patient was revised to change the implant on (b)(6) 2017.A review by a clinical consultant noted unknown trident shell malposition and incomplete seating of an msm liner in the trident shell as being procedure-related factors contributing to the dislocation event.

• Brand Name: TRIDENT PSL HA CLUSTER 52MM
• Common Device Name: PROSTHESIS, HIP, SEMI-CONSTRAINED, METAL/POLYMER, POROUS UNCEMENTED
• Manufacturer (Section D): STRYKER ORTHOPAEDICS-MAHWAH; 325 corporate drive; mahwah NJ 07430
• MDR Report Key: 6977725
• Report Number: 0002249697-2017-03106
• Device Sequence Number: 1495842
• Product Code: LPH
• UDI-Device Identifier: 07613327037197
• UDI-Public: 07613327037197
• Combination Product (Y/N): N
• Initial Reporter Country: FR
• PMA/510(K) Number: K143085
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2017
• Device Explanted Year: 2017
• Reporter Type: Manufacturer
• Report Source: health professional,other
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 10/25/2017

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: Health Professional
• Device Expiration Date: 09/21/2021
• Device Catalogue Number: 542-11-52E
• Device Lot Number: 56904501
• Was Device Available for Evaluation?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 09/28/2017
• Initial Report FDA Received Date: 10/25/2017
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Hospitalization; Required Intervention
• Patient Age: 82 YR