Modes of failure following locking plate fixation of the distal radius: a thematic analysis of 517 fractures

Anterior locking plate fixation of the distal radius is a common procedure with reliable results. Failure of fixation is sometimes seen. The aim of the present study was to identify the reasons for failure. In total, 517 cases met the study inclusion criteria. Of them, 23 cases had failure of fixation (4.4%). Failure analysis generated qualitative data. Subsequent thematic analysis identified the primary mode of failure and contributing factors. Primary modes were identified as failure to support all key fracture fragments (n = 20), wrong choice of implant (n = 1), failure of union (n = 1) and poor bone quality (n = 1). Contributing factors were errors in plate positioning, fracture reduction, implant selection and screw configuration, as well as fracture pattern complexity and poor bone quality. Most failed fixations had a primary mode and two or three contributing factors. Overall anterior plating is reliable with a low rate of surgical failure. Knowledge of failure modes will aid operative planning and prevent failure.Level of evidence: V.

A Systematic Analysis of Recent Technology Trends of Microfluidic Medical Devices in the United States

In recent years, the U.S. Food and Drug Administration (FDA) has seen an increase in microfluidic medical device submissions, likely stemming from recent advancements in microfluidic technologies. This recent trend has only been enhanced during the COVID-19 pandemic, as microfluidic-based test kits have been used for diagnosis. To better understand the implications of this emerging technology, device submissions to the FDA from 2015 to 2021 containing microfluidic technologies have been systematically reviewed to identify trends in microfluidic medical applications, performance tests, standards used, fabrication techniques, materials, and flow systems. More than 80% of devices with microfluidic platforms were found to be diagnostic in nature, with lateral flow systems accounting for about 35% of all identified microfluidic devices. A targeted analysis of over 40,000 adverse event reports linked to microfluidic technologies revealed that flow, operation, and data output related failures are the most common failure modes for these device types. Lastly, this paper highlights key considerations for developing new protocols for various microfluidic applications that use certain analytes (e.g., blood, urine, nasal-pharyngeal swab), materials, flow, and detection mechanisms. We anticipate that these considerations would help facilitate innovation in microfluidic-based medical devices.

Comparing the Fracture Resistance and Modes of Failure in Different Types of CAD/CAM Zirconia Abutments with Internal Hexagonal Implants: An In Vitro Study

Three groups of zirconia abutments (n = 5) consisting of different connection designs or manufacturers were investigated (All-Zr, ASC-Zr, and AM-Zr groups). All-electric dynamic test instruments were used to place static loading on a specimen with a crosshead speed set at 1 mm/min. A Kruskal-Wallis test and a post hoc Mann-Whitney U test were used for statistical evaluation. The mean fracture resistance was 252.37 ± 82.79 N for the All-Zr group, 384.62 ± 45.24 N for ASC-Zr group, and 361.83 ± 90.31 N for the AM-Zr group. The difference of fracture resistance between the three groups was marginally significant (Kruskal-Wallis test, p = 0.054), with the ASC zirconia abutment tending to have higher fracture resistance than the full zirconia abutment. The modes of failure among the three types of abutments are different. The All-Zr group showed an oblique fracture line starting from the buccal aspect at the region of the implant platform. While the ASC-Zr and AM-Zr groups showed a relatively horizontal fracture line with a greater distance from the implant platform. The titanium inserts cannot significantly improve the fracture resistance of the zirconia abutment. However, they may alter the modes of failure, allowing buccal fracture surfaces of the zirconia abutments to be placed away from the implant platform, thereby protecting the implant-abutment connection.

Contemporary post-marketing adverse events and modes of failure related to VASCADE Vascular Closure System: The utility of the MAUDE database

OBJECTIVES

To analyze post-marketing surveillance data from the United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database for the VASCADE Vascular Closure System (Cardiva Medical Inc., Santa Clara, CA).

BACKGROUND

The VASCADE Vascular Closure System is a closure device for femoral arterial and venous access-site closure that was approved by the FDA in 2013. However, post-marketing data and experience on the most commonly reported complications and modes of failure associated with the VASCADE Vascular Closure System are limited.

METHODS

Post-marketing surveillance data from the FDA MAUDE database from October 2013 through March 2020 were analyzed, yielding 201 reports.

RESULTS

Of the 201 reports of major complications involving VASCADE devices, 156 reports involved either injury (145) or death (11) related to the device. Of the 145 injury reports, bleeding was the most common adverse outcome described (85), followed by pseudoaneurysm (29) and pulselessness of an extremity (21). The device malfunction incidents (41 reports) were reported in three main categories, with deployment failure being the most commonly reported complication.

CONCLUSIONS

Our analysis of the MAUDE database demonstrates that in contemporary post-marketing practice, physicians should be well-trained and educated to use the VASCADE closure device because improper utilization is a common cause of device failure, and complications with the VASCADE device can have profound clinical implications.

Hueter Anterior Approach for Metal-on-Metal Hip Resurfacing Arthroplasty: 555 Cases at a Minimum Five-Year Follow-Up

BACKGROUND

Purpose of this study was to determine implant survivorship and resultant outcomes, including modes of failure, for metal-on-metal hip resurfacing through the Hueter anterior approach (HAA).

METHODS

Retrospective review of cases from 2006 to 2015, resulted in 555 metal-on-metal hip resurfacing via HAA, mean age 49.4 ± 6.9 years and mean BMI 28.1 ± 5.3. Kaplan-Meier curves were used to assess implant survivorship. Evaluation of technique was based on radiographic assessment of component position at 6 weeks. Patient-reported outcome measures were assessed using 12-Item Short Form Survey 12, University of California Los Angeles activity, Western Ontario and McMaster Universities Osteoarthritis Index, and hip disability osteoarthritis outcome scores.

RESULTS

At a mean follow-up of 9.18 years, survivorship was 95.0% at 5 years (95% CI: 93.2-96.8 years) and 92.5% at 10 years (95% CI: 90.0-95.0 years); men at 96.1% (95% CI: 94.3-97.9) and 93.8% (95% CI: 91.1-96.5), and women at 88.8% (95% CI: 81.9-95.7) and 85.6% (95% CI: 77.6-93.6), 5 and 10 years, respectively (P = .033). There were 37 revisions to total hips (7%) at a mean time of 3.3 years (SD 2.7). Indications for revision were aseptic loosening of acetabular (n = 12) and femoral component (n = 7) and pseudotumor (n = 6). Radiographic parameters were respectable and consistent, median acetabular inclination angle 41.2° and femoral stem shaft angle 137.7°. Patient-reported outcome measure scores significantly improved and remained stable at 2 and 5 years postoperatively.

CONCLUSION

Although choice of surgical approach should always be based on surgeon's technical expertise, this study has shown that HAA is safe and effective for hip resurfacing. Mindful attention to long-term metal ion exposure must still be considered.

Real-world experience of suture-based closure devices: Insights from the FDA Manufacturer and User Facility Device Experience

OBJECTIVES

We analyzed post-marketing surveillance data from the United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database for suture-based vascular closure devices (VCDs) - Perclose ProGlide (Abbott, Chicago, Illinois) and Prostar XL (Abbott).

BACKGROUND

Suture-based VCDs are mostly used for large-bore femoral arterial access-site closure. Real-world, contemporary experience on the most commonly reported complications and modes of failure associated with these devices is limited.

METHODS

Post-marketing surveillance data from the FDA MAUDE database, for the ProGlide system and for the Prostar XL system, were analyzed, yielding 827 Perclose ProGlide reports and 175 Prostar XL reports.

RESULTS

Of the 827 reports of major complications involving the Perclose ProGlide devices, 404 reports involved injury, and one involved death related to the device. In the Prostar XL analysis, 94 reports involved injury, and one involved death. Bleeding from vessel injury was the most common adverse outcome described with both devices, followed by hematoma and thrombus. Surgical repair was the most commonly used treatment strategy. In terms of device malfunction, suture-related malfunction (212 reports) was most commonly seen in the Perclose ProGlide group, while failed deployment was most commonly seen in the Prostar XL group.

CONCLUSIONS

Our analysis of the MAUDE database demonstrates that in real-world practice, suture-based VCDs were found to be associated with complications, including vascular injury, difficulties with the device itself, and even death. Ongoing user education and pre-procedural patient selection are important to minimize risks associated with suture-based vascular closure devices.

Outcomes of a Fixed-Bearing, Medial, Cemented Unicondylar Knee Arthroplasty Design: Survival Analysis and Functional Score of 460 Cases

BACKGROUND

Unicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty in isolated medial osteoarthritis (OA). However, despite satisfactory reports on the clinical performance, UKA revision rates are still concerning. This retrospective study reports on the long-term survivorship, functional outcomes, and reasons for revision in fixed-bearing UKA implant.

METHODS

Between 2005 and 2013, 460 consecutive patients were treated with medial UKA in one center using a fixed-bearing UKA system. All patients were evaluated clinically and radiographically before surgery, and postoperatively at 6 weeks and 1 year. Between February and April 2016, all patients were reevaluated using the Oxford Knee Score.

RESULTS

Mean follow-up was 5.5 (range, 2-11) years. The mean Oxford Knee Score was 43.3 (7-48), with 94.6% patients showing excellent or good outcomes. Eleven revisions (2.4%) occurred. The survivorship was 97.2% (95% confidence interval, 96.2%-99.2%) and 94.2% (95% confidence interval, 86.8%-97.5%) at 5 and 10 years, respectively, with revision of any implant component for any reason as the end point. The causes for revision were infection (4 cases, 0.9%); lateral pain due to overload (2 cases, 0.4%); progression of OA in the lateral compartment (2 cases, 0.4%); patellar pain with patellar chondropathy (2 cases, 0.4%); and severe synovitis (1 cases, 0.2%). There were no reoperations or revisions for component loosening, instability, component wear, or periprosthetic fracture.

CONCLUSION

A fixed-bearing UKA system is a good treatment option for medial end-stage OA. Satisfactory functional results were achieved with low incidence of complications and revisions.

Mid-flexion instability after total knee arthroplasty: woolly thinking or a real concern?

The term mid-flexion instability has entered the orthopaedic literature as a concept, but has not been confirmed as a distinct clinical entity. The term is used freely, sometimes as a synonym for flexion instability. However, the terms need to be clearly separated. A cadaver study published in 1990 associated joint line elevation with decreased stability at many angles of flexion, but that model was not typical of clinical scenarios. The literature is considered and it is proposed that the more common entity of an uncorrected flexion contracture after a measured resection arthroplasty technique is more likely to produce clinical findings that suggest instability mid-flexion. It is proposed that the clinical scenario encountered is generalised instability, with the appearance of stability in full extension from tight posterior structures. This paper seeks to clarify whether mid-flexion instability exists as an entity distinct from other commonly recognised forms of instability.

Why Do Medial Unicompartmental Knee Arthroplasties Fail Today?

BACKGROUND

Failure rates are higher in medial unicompartmental knee arthroplasty (UKA) than total knee arthroplasty. To improve these failure rates, it is important to understand why medial UKA fail. Because individual studies lack power to show failure modes, a systematic review was performed to assess medial UKA failure modes. Furthermore, we compared cohort studies with registry-based studies, early with midterm and late failures and fixed-bearing with mobile-bearing implants.

METHODS

Databases of PubMed, EMBASE, and Cochrane and annual registries were searched for medial UKA failures. Studies were included when they reported >25 failures or when they reported early (<5 years), midterm (5-10 years), or late failures (>10 years).

RESULTS

Thirty-seven cohort studies (4 level II studies and 33 level III studies) and 2 registry-based studies were included. A total of 3967 overall failures, 388 time-dependent failures, and 1305 implant design failures were identified. Aseptic loosening (36%) and osteoarthritis (OA) progression (20%) were the most common failure modes. Aseptic loosening (26%) was most common early failure mode, whereas OA progression was more commonly seen in midterm and late failures (38% and 40%, respectively). Polyethylene wear (12%) and instability (12%) were more common in fixed-bearing implants, whereas pain (14%) and bearing dislocation (11%) were more common in mobile-bearing implants.

CONCLUSION

This level III systematic review identified aseptic loosening and OA progression as the major failure modes. Aseptic loosening was the main failure mode in early years and mobile-bearing implants, whereas OA progression caused most failures in late years and fixed-bearing implants.

The problem total knee replacement: systematic, comprehensive and efficient evaluation

There are many reasons why a total knee replacement (TKR) may fail and qualify for revision. Successful revision surgery depends as much on accurate assessment of the problem TKR as it does on revision implant design and surgical technique. Specific modes of failure require specific surgical solutions. Causes of failure are often presented as a list or catalogue, without a system or process for making a decision. In addition, strict definitions and consensus on modes of failure are lacking in published series and registry data. How we approach the problem TKR is an essential but neglected aspect of understanding knee replacement surgery. It must be carried out systematically, comprehensively and efficiently. Eight modes of failure are described: 1) sepsis; 2) extensor discontinuity; 3) stiffness; 4) tibial- femoral instability; 5) patellar tracking; 6) aseptic loosening and osteolysis; 7) periprosthetic fracture and 8) component breakage. A ninth 'category', unexplained pain is an indication for further investigation but not surgery.