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At the time of this initial mdr report, the investigation into the cause of the event is still ongoing.The initial complaint report noted that the patient was non-compliant with post-operative care instructions.In an interview with the treating physician, he noted in both the first week and second week follow up visits that she had wiggled her hand up the tube of the cast, and that her adult children reported she continued to engage in lifting and other activities with the injured arm.The firm has conducted a follow-up interview with the treating physician, and collected additional information about the initial implantation procedure, his observations about the patient condition at the time of the 2 week followup, and about the revision surgery.On (b)(6) 2022 the firm received x-rays from the treating physician from pre- and post-op of the index procedure on (b)(6) 2022, from the 2 week follow up with the patient on (b)(6) 2022 where he identified the displacement of the fracture and the angulation of the fracture site that he determined to treat, and pre- and post-op from the revision surgery performed on (b)(6) 2022.The firm will conduct a medical oversight review of these records to support the investigation into the cause of the event.The firm performed a review of the manufacturing records and found that devices met specification at the time of manufacture and release.The firm is attempting to retrieve the product in order to perform device evaluation.A follow up mdr will be submitted when further information is known about this case.
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At the time of the initial mdr submission for this event, the investigation into the cause of this event was still underway.This followup mdr is submitted to submit new information, including - returned product evaluation information - the investigation findings codes - investigation conclusion codes - and this manufacturer's narrative with the firm's root cause conclusions.Follow up information from the user: · the user reported that the post revision surgery the patient is doing well.He reported that she was casted for 6 weeks from the revision surgery, and now she looks stable and her condition good, and that he doesn't anticipate any further issues.· the treating physician reported that in both the first week and second week follow up visits he observed patient noncompliance with his post op care instructions.At the first post-op visit, the patient had wiggled out of her splint.At the second post-op visit, she had wiggled partially out of her cast such that her hand was in the tube of the cast leaving the portion of her arm that was fractured outside of the cast.Additionally, he shared that the patient's adult children reported that she continued to engage in lifting and other activities with the injured arm throughout this time.He also shared that the patient was a gastric bypass patient, so she had some deficiencies and excess skin which allowed her to partially wiggle out of her cast.· in addition to patient noncompliance, the user reported that there was a little bit of movement at the fractures after the illuminoss implants were implanted and cured, which indicated to him that either he hadn't filled up the implants completely, or that the implants weren't completely hardened from the curing.The user reported that he decided to address the movement he observed at the fracture sites at that initial implantation by securing the patient in a cast.The user stated the initial implant curing went as planned and there was no unusual events or damage to the implant.When the user separated the catheter from the implant it appeared fully cured and there was no leakage.· for the revision surgery performed on november 8th, the user reported that both the radius and ulna were lined up perfectly and that he didn't need to do any reduction before adding the plate.When he drilled into the implants to secure the plate, the feeling was somehow different than in his past experienced with illuminoss implants.In this situation the implants felt different from when he has drilled into illuminoss implants in the past, but also not the same as the feeling of just drilling into bone with no illuminoss implant.He reported being able to get a great "bite" with the screws and stabilize the fracture.Product evaluation: the implants were not able to be returned and evaluated because they remained in the patient.Manufacturing records for the two implant lots used in this case were reviewed and found to be in specification at the time of manufacture and release.In light of the user's statement that the movement he observed at the fracture site upon initial implantation, as well as the feeling of the bone when he was drilling into it to perform the revision surgery, indicated to him that either the implants were insufficiently cured or they were underfilled, the firm retrieved the light boxes used in this case to perform device evaluation.The two light boxes used in the case were returned to illuminoss on december 15, 2022 and evaluated.Both light boxes were tested and found to have in specification light output.No problem was found with the light boxes.A review of the manufacturing records for these two light boxes found that they were in specification at the time of manufacture and release.Medical oversight review the firm conducted a medical oversight review of these records to support the investigation into the cause of the event.On (b)(6) 2022 the firm received x-rays from the treating physician from pre- and post-op of the index procedure on (b)(6) 2022, from the 2 week follow up with the patient on (b)(6) 2022 where he identified the displacement of the fracture and the angulation of the fracture site that he determined to treat, and pre- and post-op from the revision surgery performed on (b)(6) 2022.The firm noted from the x-rays that the patient has a large forearm with a lot of redundant skin.The firm also noted that there is a lot of comminution of the fracture of the ulna.In the x-rays from the 2 week followup visit on (b)(6), the implants appear bent, not broken, because the spiral marker along the outside of the implant is continuous.The firm's medical oversight concluded that the patient noncompliance likely aggravated the fracture.We confirm the user's assessment that the redundant soft tissue (extra skin and adipose) visible in the x-rays meant that there was a lot of wiggle room in the cast, which undermined the security that the cast provided.In addition to the excess skin and weight of the patient's arm, the patient's hand halfway out of the cast meant that she was halfway levering at the fracture site.The firm also noted that the canal diameter of the ulna was quite small.Investigation summary: the firm identified three potential factors which may have contributed to the loss of stability and the illuminoss implants bending: patient noncompliance facilitated by redundant skin, insufficient implant curing, and insufficient initial fixation.Patient noncompliance facilitated by redundant skin the medical oversight review concluded that the patient noncompliance was likely to have aggravated the fracture because the arm halfway out of the cast means the patient was halfway levering at the fracture site and applying additional forces to the fractures.The medical oversight review also concluded that the redundant skin and adipose reduced the security provided by the cast by allowing movement inside the cast.These factors likely contributed to the implants bending and loss of fracture stabilization.Insufficient implant curing the potential that insufficient implant curing occurred and contributed to the implant bending and loss of fracture stabilization was further investigated.The user's description of the implants "sway" at the fracture site after curing, and the difference in feel when drilling screws in the implants compared to previous implants suggests that the two implants may not have been fully cured.Once cured the illuminoss implants are solid, so it would not be expected that an implant can "sway" once fully cured in the bone.The illuminoss implant cures from the central lumen of the implant outward, so if there was insufficient light delivered to the implant, a partially cured implant would be solid in the center and soft on the outer diameter.This hypothesized failure mode would align with the observations provided by the user because it would explain the observed "sway" and bend at the fracture site, the solidity of the bone and implant experienced when drilled into, and the presence of the fully hardened portion of the implant via the large incision site that did not leak upon separation of the catheter.There are three main potential causes for an implant to be insufficiently cured: insufficient light output or duration from the light box, insufficient light transmission by the light fiber, or incorrect monomer composition.· the light box output of the two light boxes potentially used during the case were evaluated and found that both light boxes had in specification light output.There is no indication that there was insufficient light output from the light box and light guide used to cure these implants.· the review of manufacturing records for the 2 implants used in this case identified that light fibers released and assembled into these lots passed the 100% inspection for absolute irradiance (ai) confirming that the time of manufacture they were in specification for light output.The light fibers from these implant kits were not able to be returned to illuminoss for evaluation, so it was not possible to determine if there was insufficient light transmission from the light fiber due to damage, kinking or mishandling of the light fiber by the user.The potential for insufficient light transmission from the light fiber causing insufficient curing cannot be confirmed nor ruled out.· the inspection records for the 2 monomer lots associated with the 2 different implant kits used were reviewed and found to include the required ftir and cure testing results that demonstrate the monomer composition meets specifications.It cannot be confirmed or ruled out that the implants in this case were insufficiently cured, therefore insufficient implant curing due to potential damage or mishandling of the light fiber may have contributed to the bent implants and loss of stabilization in this case.Insufficient initial fixation the user described that the initial fixation was insufficient as there was a "sway" or movement of the implants at the fracture site.Internal medical oversight observed that the ulna fracture was highly comminuted.The comminution of the ulna may have caused the initial fixation of the ulna to "sway" or move due to the bone fragments which are not able to be stabilized with an intermedullary implant.The initial fixation may have also been insufficient due to the small intermedullary canal diameter and resulting small implant diameter.The implant diameters were estimated to be about 7mm in the ulna and 6mm in the radius over the fracture location.The insufficient initial fixation and small implant diameter may have contributed to the implants bending and eventual loss of fracture stability, however this cannot be confirmed.Review of ifu and potential user error this case treated a radius and ulna fracture which is included in the product's indications in the us where this treatment occurred.The instructions for use 900356_w describes the risks "as with any im fixation system or rod the following can occur: loosening, bending, cracking, fracture, or mechanical failure of the components or loss of or inadequate fixation in bone attributable to delayed union, nonunion, insufficient quality of bone, markedly unstable comminuted fractures or insufficient initial fixation, loss of anatomic position with nonunion or malunion with rotation or angulation." the risk of implant bending is captured in the ifu.User error may have contributed to the complaint, but it cannot be confirmed.If the implants were insufficiently cured one potential cause includes user mishandling or damaging the light fiber resulting in insufficient light transmission to the monomer.However, as the light fibers were disposed of at the hospital and could not be returned for evaluation, it cannot be determined if this contributed to the implant failure.Conclusion after the firm's investigation, there remain three potential causes for the implant bending and loss of fracture stabilization, including patient noncompliance facilitated by redundant skin, insufficiently cured implant due to user mishandling or damaging the light fiber, and insufficient initial fixation.As the firm was unable to definitively identify the root cause of the implants bending, the root cause of this complaint is undetermined.
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