Length of Endoprosthetic Reconstruction in Revision Knee Arthroplasty Is Associated With Complications and Reoperations

Factors Associated With Failure Following Proximal Femoral Replacement for Salvage Hip Surgery for Nononcologic Indications

BACKGROUND

Proximal femoral replacement (PFR) is used when extensive proximal femoral bone loss is encountered during revision total hip arthroplasty. However, further data on 5-to-10-year survivorship and predictors of failure are needed. Our aim was to assess the survivorship of contemporary PFRs used for nononcologic indications and determine factors associated with failure.

METHODS

A single-institution retrospective observational study was conducted between June 1, 2010 and August 31, 2021 for patients undergoing PFR for non-neoplastic indications. Patients were followed for a minimum of 6 months. Demographic, operative, clinical, and radiographic data were collected. Implant survivorship was determined via Kaplan-Meier analysis of 56 consecutive cemented PFRs in 50 patients.

RESULTS

At a mean follow-up of 4 years, the mean Oxford Hip Score was 36.2 and patient satisfaction was rated at an average of 4.7 of 5 on the Likert scale. Radiographic evidence of femoral-sided aseptic loosening was determined in 2 PFRs at a median of 9.6 years. The 5-year survivorship with all-cause reoperation and revision as end points was 83.2% (95% Confidence Interval [CI]: 70.1% to 91.0%) and 84.9% (95% CI: 72.0% to 92.2%), respectively. The 5-year survivorship was 92.3% (95% CI: 78.0% to 97.5%) for stem length > 90 mm compared to 68.4% (95% CI: 39.5% to 85.7%) for stem length ≤ 90 mm. A construct-to-stem length ratio (CSR) ≤ 1 was associated with a 91.7% (95% CI: 76.4% to 97.2%) survival, while a CSR > 1 was associated with a 73.6% (95% CI: 47.4% to 88.1%) survival.

CONCLUSION

A PFR stem length ≤ 90 mm and CSR > 1 were associated with increased rates of failure.

Megaprosthesis in Non-Oncologic Settings-A Systematic Review of the Literature

Modular megaprostheses (MPs) are commonly used after bone-tumor resection, but they can offer a limb salvage solution in massive bone defects. The aim of this systematic review of the Literature is to provide a comprehensive data collection concerning the use of MPs in non-oncologic cases, and to provide an overview of this topic, especially from an epidemiologic point of view. Three different databases (PubMed, Scopus, and Web of Science) were searched for relevant articles, and further references were obtained by cross-referencing. Sixty-nine studies met the inclusion criteria, reporting on cases of MP in non-oncologic cases. A total of 2598 MPs were retrieved. Among these, 1353 (52.1%) were distal femur MPs, 941 (36.2%) were proximal femur MPs, 29 (1.4%) were proximal tibia MPs and 259 (10.0%) were total femur MPs. Megaprostheses were most commonly used to treat periprosthetic fractures (1158 cases, 44.6%), in particular in the distal femur (859, 74.2%). Overall, complications were observed in 513 cases (19.7%). Type I (soft tissue failures) and type IV (infection) according to the Henderson classification were the most frequent (158 and 213, respectively). In conclusion, patients with severe post-traumatic deformities and/or significant bone loss who have had previous septic complications should be considered as oncologic patients, not because of the disease, but because of the limited therapeutic options available. The benefits of this treatment include relatively short operative times and immediate weight-bearing, thus making MP particularly attractive in the lower limb.

Early Infection After Aseptic Revision Knee Arthroplasty: Prevalence and Predisposing Risk Factors

BACKGROUND

Although patient factors have been associated with prosthetic joint infection (PJI) after primary total knee arthroplasty, there are insufficient data on the relationship of patient and technical factors with early PJI after aseptic revision.

METHODS

This is a retrospective study of 157 aseptic revisions performed by 2 surgeons at 1 academic center. A negative intraoperative culture during revision surgery was required for inclusion. Mean follow-up time was 3.8 years (standard deviation 2.8). PJI was defined by positive aspiration or draining wound, and an additional operation within 1 year of aseptic revision. Patient demographics, medical comorbidities, and technical factors were reviewed. Data points were evaluated with univariate and adjusted multivariate regression analyses.

RESULTS

The prevalence of PJI after aseptic revision was 9% (14/157). The most common organism was Staphylococcus aureus. Initial treatment included debridement and liner exchange (11) and antibiotic spacer (3). Two patients ultimately had an above-knee amputation. Univariate analysis showed a significant difference in preoperative anemia (P < .01), transfusion (P < .01), and diabetes (P = .05) between cohorts. There was no association among the length of surgery, use of a metaphyseal cone, or the number of components revised and PJI. Adjusted logistic regression demonstrated that preoperative anemia (P < .01) was a significant risk factor for PJI.

CONCLUSION

The prevalence of early PJI was similar to other studies in the literature. Anemia was an independent predictor of PJI, while technical factors did not have an association. Medical optimization of patients should be considered prior to revision surgery.

Hot spots and trends in knee revision research since the 21st century: a bibliometric analysis

Background

With the popularization of knee replacement surgery in the treatment of the advanced lesions of knee joint, the amount of knee revision surgery is increasing unceasingly. Meanwhile, the continuous introduction of new clinical concepts and new technology poses a challenge to researchers and surgeons. Our study aims to inform the future scientific research and clinical treatment, by investigating the hot spots and trends of the knee revision research field with the method of bibliometric analysis.

Methods

Publications on knee revision included in the database of Web of Science Core Collection (WoSCC) between 2000 and 2018 were reviewed and MeSH terms of them were extracted from PubMed. Online bibliometric analysis website (http://bibliometric.com/), two pieces of software called “CiteSpace” and “Bibliographic Item Co-Occurrence Matrix Builder” (BICOMB) were used to analyze the publications reviewed at quantitative level. Another piece of software called “gCLUTO”, was used to investigate the hot spots with visualization techniques at qualitative level.

Results

A total of 906 publications were retrieved between 2000 and 2018. There is an increasing number of publications, from 15 in 2000 to 86 in 2018. Journal of Arthroplasty is the leading journal which has the most publications on knee revision. The United States has been the biggest contributor. Mayo Clinic became the leader among the institutions which have conducted correlational researches. David G. Lewallen, Robert L. Barrack and Michael A. Mont should be regarded as the scholars who have made outstanding contribution. Hot spots were summed up in six clusters, respectively, the solutions for infection, prostheses, the adverse effects, the surgical techniques, epidemiological characters, and the pathophysiology of the revision knee.

Conclusions

We found a growing trend in knee revision research and extracted the most contributive researchers, institutions, countries, journals, and most-cited articles worldwide. The solutions for complications, surgical applications and analysis for epidemiological characters have been the hot spots. Multi-disciplinary integration is becoming the time-trend of hot spots. Minimally invasive and navigation are directions of revision surgery. They together constitute a solid foundation and set up a fingerpost for the future scientific research and clinical treatment.

Irrigation and Debridement with Chronic Antibiotic Suppression Is as Effective as 2-Stage Exchange in Revision Total Knee Arthroplasty with Extensive Instrumentation

BACKGROUND

Extraction of implants because of periprosthetic infection (PJI) following complex revision total knee arthroplasty (rTKA) with extensive instrumentation is a daunting undertaking for surgeon and patient alike. The purpose of the present study was to evaluate whether infections following complex rTKA are better treated with 2-stage exchange or irrigation and debridement (I&D) with modular component exchange and antibiotic suppression in terms of infection control, reoperation, and function.

METHODS

We reviewed rTKAs that had been performed for the treatment of PJI from 2005 to 2016. Extensive instrumentation was defined as the presence ≥1 of the following: metaphyseal cones/sleeves, distal femoral replacement, periprosthetic fracture instrumentation, or fully cemented stems measuring >75 mm. Cases were categorized according to the initial treatment (I&D with antibiotic suppression or initiation of 2-stage exchange).

RESULTS

Eighty-seven patients with PJI and extensive instrumentation were identified: 56 patients who were managed with I&D with suppression and 31 who were managed with the initiation of 2-stage exchange. The rate of success (defined as no reoperation for infection) was similar for the 2 groups (62.5% the I&D group compared with 67.7% for the 2-stage group; p = 0.62). The rate of mortality was also similar (39.3% for the I&D group compared with 38.7% for the 2-stage group; p = 0.96). Of the 31 patients in the 2-stage group, 18 (58.1%) underwent reimplantation with a revision replacement. Of those 18 patients, 13 were still infection-free at the time of the most recent follow-up; however, when the analysis was expanded to all 31 patients in the 2-stage group, only 13 (41.9%) both had a successful reimplantation and did not require additional surgery for infection. Nine (29.0%) of the 31 patients in the 2-stage group never underwent the second stage, and 4 (12.9%) of the 31 required arthrodesis at the second stage. In contrast, 35 (62.5%) of the 56 patients in the I&D group were successfully managed, without additional surgery for the treatment of infection. At the time of the latest follow-up (mean, 3.2 years; range, 2 to 13 years), more patients in the I&D group were ambulatory (76.8% in the I&D group compared with 54.8% in the 2-stage group; p = 0.05) and maintained a functional bending knee joint (85.7% in the I&D group compared with 45.2% in the 2-stage group; p < 0.001).

CONCLUSIONS

In the treatment of periprosthetic infection of rTKA with extensive instrumentation, I&D with chronic antibiotic suppression was as effective as 2-stage exchange in terms of preventing reoperation for infection and was more effective in terms of maintaining function. These data apply to rTKA with extensive periarticular instrumentation and should not be extrapolated to primary or simple revision implants.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Bone Defects in Revision Total Knee Arthroplasty

The increase in the number of revision total knee arthroplasty surgeries has been observed in recent years, worldwide, for several causes. In the United States, a 601% increase in the number of total knee arthroplasties, between 2005 and 2030, is estimated. Among the enormous challenges of this complex surgery, the adequate treatment of bone defects is essential to obtain satisfactory and lasting results. The adequate treatment of bone defects aims to build a stable and lasting support platform for the implantation of the definitive prosthetic components and, if possible, with the reconstruction of bone stock. Concomitantly, it allows the correct alignment of the prosthetic and limb components, as well as restoring the height of the joint interline and, thus, restoring the tension of soft parts and load distribution to the host bone, generating a joint reconstruction with good function, stable, and painless. There are several options for the management of these bone defects, among them: bone cement with or without reinforcement with screws, modular metallic augmentations, impacted bone graft, structural homologous graft and, more recently, metal metaphyseal cones, and metaphyseal sleeves. The objective of the present article was to gather classic information and innovations about the main aspects related to the treatment of bone defects during revision surgeries for total knee arthroplasty.

Proximal femoral replacement in non-oncologic patients undergoing revision total hip arthroplasty

PURPOSE

Proximal femoral replacements (PFRs) have been recently utilized in complex revision arthroplasties where proximal femoral bone is compromised. The purpose of this study is to evaluate the clinical outcomes, complications, and survivorship of PFRs as a salvage treatment for severe bone loss after non-oncologic revision total hip arthroplasty.

METHODS

This is a retrospective review of all patients who underwent femoral revision surgery using a single design PFR between 2004 and 2013 at our institution. Forty patients (41 hips) were included with a mean age of 64 years (29-90). According to Paprosky classification, 15 femurs had type IIIB defect, and 26 had type IV defect. Patients were followed for a mean of five years (2-10). The average length of reconstruction was 150 mm (81-261). A Kaplan-Meier analysis was used to determine the survival of the PFR.

RESULTS

A total of nine patients (9 PFRs, 22%) were re-operated upon. Three re-operations were for infection, two for dislocation, two for aseptic loosening, and two for periprosthetic fracture. The survivorship at five years was 95.1% for revision of the femoral stem for aseptic loosening. We did not find length of the segmental reconstruction or the indication for revision, to be a risk factor for implant failure or re-revision.

CONCLUSIONS

Proximal femoral replacements have shown an acceptable survivorship in non-oncologic revision hip arthroplasties for severe proximal femoral bone loss. The frequent use of constrained liners may decrease the risk of dislocation due to the loss of the abductor mechanism encountered in these complex reconstructions.

REVIEW OF TOTAL KNEE ARTHROPLASTY AND THE BRAZILIAN UNIFIED HEALTH SYSTEM: A NATIONAL PROBLEM

OBJECTIVES

To analyze, through DATASUS data, the historical trend of revision of total knee arthroplasty (TKA) in the period between 2008-2016 and to relate them to demographic, regional and national aspects.

METHODS

Elaboration of a historical series between the period 2008-2016, using the database of DATASUS, in the area of Health Information (TABNET). In order to calculate the incidence, the total number of TKA revisions and as denominator the total national, regional or state population for the period studied was used as numerator.

RESULTS

The national rate of procedures per 100,000 inhabitants varied between 0.41 and 0.48 in the analyzed period (mean of 0.44). The Southeast region, with 69% of the SBCJ accredited services and 61% of the SBCJ members, was responsible for 60% of the absolute number of procedures performed in Brazil.

CONCLUSIONS

In absolute numbers, the Southeast region has the highest volume of procedures. However, the highest rate is found in the South region. The North, Northeast and Central-West regions presented unsatisfactory results, well below the others. Level of evidence IV, Economic and decision analysis - development of economic model or decision.

The role of rotating hinge implants in revision total knee arthroplasty

Hinged implants are the most constrained knee replacement prostheses. They are very useful in complex cases of total knee arthroplasty (TKA) revision.

Hinged implants have evolved with rotating bearings and modularity that allows local joint reconstruction or segmental bone replacement.

They are required when significant instability persists in cases with inadequate collateral ligaments and significant flexion laxity.

They are now used when a large bone defect is reconstructed, or when bone fixation of the implant is questionable especially in the metaphyseal zone.

The use of hinged implants in TKA revision is associated with high complication rates. Published outcomes differ based on the patients’ aetiology.

The outcomes of rotating-hinged implants used in septic revisions or salvage situations are poorer than other types of revision and have a higher complication rate.

The poor general health of these patients is often a limitation.

Despite these relatively poor results, hinged implants continue to have a place in revision surgery to solve major instability or to obtain stable bone fixation of an implant when the metaphysis is filled with bone grafts or porous devices.

Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180070