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The manufacturer did not receive devices, x-rays, or other source documents for review.
As no lot numbers were provided for the devices, the device history records could not be reviewed.
A cause for this specific event cannot be ascertained from the information provided.
Additional information has been requested and is not currently available.
Should additional information become available and an investigation result be available, that changes this assessment, an amended medical device report will be submitted.
(b)(4).
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No trend identified.
The device manufacturing quality records indicate that the released components met all requirements to perform as intended.
Event description (event details, per) in the event information section the (b)(6) 2016 is given as the date alleged event occurred.
The description states that the patient was not able to move the extremity which resulted in a revision surgery.
It is also stated that there is a problem with the articulation.
It seems to get stuck during movements.
Review of received data: - video from customer: the short video sequence shows that during surgery an instrument is entered through the bore for the ulnar peg in the hinge of the humeral component.
It is then moved by hand with the help of the instrument.
Devices analysis: - as received condition: the explants were received in a packaging that is commonly used for autoclaving.
The color code of the packaging had a brownish color.
This indicates that steam sterilization was performed.
- visual examination: the anchoring surfaces of the humeral component are inconspicuous.
The hinge is still mounted in the humeral component.
The hinge cannot be moved at all by hand.
The polyethylene-pin-bushings are deformed in such a way that on the dorsal side the polyethylene fills the gap between hinge and humeral component on one side while on the ventral side both gaps are filled.
On the cylindrical surface of the hinge a small polished zone can be recognized.
The polyethylene-bushing in the bore for the ulnar peg is missing.
On the dorsal side there is a slight deformation on the bore¿s edge.
On the ventral side an approximately 1 to 2 mm wide, polished, almost circumferential stripe can be seen on the face surface around the bore.
The edge of the bore is polished and slightly deformed on approximately three quarter of its circumference.
The bore surface itself is intact.
On the hinge and on both humeral gliding surfaces diffuse scratches are visible.
The collar of the ulnar component shows some scratches on its circumference as well as slight damage on its bottom side.
These can probably be attributed to the revision surgery.
The anchoring surfaces of the ulnar component are inconspicuous.
The peg of the component exhibits several diffuse scratches.
On the face surface of the collar around the peg there is an almost circumferential polished stripe close to the outer edge of the surface.
Additionally, three deeper appearing polished lines can be seen on one side.
Further, a polished stripe can be noticed close to the peg¿s bottom on both of its small sides as well as one long side.
Closer inspection of the stripe with a low power microscope with up to 40x magnification (wild m38, (b)(4)) revealed that due to wear and deformation some material was displaced that forms a little ledge.
On the long side of the peg on both ends of the stripe conspicuous areas were identified.
The latter were examined with the microscope type leica dmrx (eq-id (b)(4)).
It seems that surface changes probably due to surface fatigue, e.
G.
Pits, occurred.
Under certain light conditions it seems that there is a slightly worn, elliptical-shaped area at the peg¿s bottom on the ventral side.
Conclusion summary: the elbow prosthesis was revised after unknown time in vivo because the patient could not move the extremity.
The explants were received in autoclaved condition.
The hinge that is mounted to the humeral component contains two polyethylene-pin-bushings.
Polyethylene should not be autoclaved as it expands under the usually applied temperatures during steam sterilization.
In the current design the polyethylene becomes deformed due to the limited space.
Therefore, it remains unknown if the deformations of the polyethylene-pin-bushings observed during investigation can be completely attributed to the steam sterilization or if there was already some deformation in the as-removed condition.
A possible deformation of the polyethylene-pin-bushings in vivo would have changed the clearance between the hinge and the opening in the humeral component.
As a consequence this could probably have led to a hindered movement of the prosthesis.
However, it remains unknown why the patient was not able to move the extremity and which factors influenced it and / or contributed to it.
The polyethylene bushing in the bore for the ulnar peg on the hinge of the humeral component is missing.
The reason for that is unknown.
The polished, almost circumferential stripe around the bore as well as the polished and deformed edge of the bore correspond to the phenomena seen on the face surface of the ulnar component¿s collar and around the bottom of the ulnar peg.
This points to a direct metal-on-metal contact between the components which indicates that the collar of the polyethylene bushing was no longer intact.
The reason for this is unknown.
Based on the given information and the results of the investigation, we were not able to identify a specific root cause for this issue.
The need for corrective measures is not indicated and zimmer (b)(4) considers this case as closed.
(b)(4).
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