Arthrodesis should be strongly considered after failed two-stage reimplantation TKA

Revision Distal Femoral Replacements Have More Than a 40% Failure and Reoperation Rate

INTRODUCTION

Distal femoral replacement (DFR) is a complex reconstruction option for patients who have substantial bone loss, often following multiple failed revision total knee arthroplasties (TKAs). However, five-year survivorship after DFR is only 70 to 85%, and there is a paucity of literature evaluating outcomes following revision DFRs (rDFRs). Therefore, this study aimed to analyze the survivorship and outcomes of rDFR.

METHODS

This retrospective study identified a consecutive cohort of all patients who underwent DFR at a single institution between 2004 and 2022. Among this population, patients who failed DFR and underwent rDFR were analyzed. All subjects had a minimum two-year follow-up from rDFR. There were 54 patients who underwent rDFR at a mean time of 19.7 months after their index DFR. The primary outcome was reoperation after rDFR. Secondary outcomes included the mechanism of failure, complications, readmission, amputation, and mortality.

RESULTS

Among the 54 patients who underwent rDFR, 22 patients (41%) failed rDFR and had a reoperation. At the most recent follow-up, patients who had rDFRs had a 46% 90-day readmission rate, 9% amputation rate, and 11% mortality rate. The 5-year reoperation-free survivorship after rDFR was 61%. Periprosthetic joint infection (PJI) was the most common indication for rDFR (43%) and the most common reason for failure of rDFR (59%). Women were significantly associated with the failure of rDFR (P = 0.029).

CONCLUSION

The outcomes following rDFR are poor, with high reoperation rates, early postoperative failure, complications, and amputation. These outcomes and risks should be shared with patients when discussing limb salvage options before these operations.

Knee fusion versus above knee amputation as two options to deal with knee periprosthetic joint infection

BACKGROUND

Periprosthetic joint infection (PJI) poses a significant challenge in total knee arthroplasty (TKA), with recurrence rates as high as 14-28%, leading to substantial morbidity and treatment costs. When conventional treatments fail, knee fusion and above-the-knee amputation (AKA) emerge as alternative options. Existing literature offers conflicting views on the efficacy and impact of knee fusion versus AKA with varied outcomes and limitations.

METHODS

This retrospective national study spanning 2010-2022 investigates Knee Fusion and AKA as options for addressing Knee PJI. Utilizing PearlDiver Patient Records Database, procedural, and reimbursement data on over 100 million individuals from all the US was evaluated. Readmission rates, costs, and complications of the mentioned procedures were assessed using ICD-9 and ICD-10 codes within a 90-day period and one-year post-operation. Statistical analyses, including chi-square tests and regression models, were conducted using integrated R software.

RESULTS

The study reveals a substantial escalation (p < 0.0001) in the proportion of patients opting for AKA compared to arthrodesis. While age as a demographic factor showed no significant difference, arthrodesis patients exhibited lower comorbidity scores (3.6 ± 2.9 vs. 4.6 ± 3.4, p < 0.001). Arthrodesis correlated with higher 90-day thromboembolism rates (9.2% vs. 7.3%, p < 0.001), blood transfusion requirements (23.2% vs. 14.4%, p < 0.001), and acute renal failure incidence (p = 0.008) but demonstrated lower rates of urinary tract infections (p = 0.047) and cerebrovascular accidents (p < 0.001). At 1 year, arthrodesis was associated with higher infection rates (38.7% vs. 36.4%, p < 0.001). Arthrodesis patients had significant increased 90-day and 1-year readmission rates and hospitalization costs ($12,732 vs. $18,826, p < 0.001).

CONCLUSIONS

We found higher rates of 1-year thromboembolism, infection, acute renal failure, and readmission in the arthrodesis group. AKA patients had more sepsis and cerebrovascular accidents. A patient-centered conversation is best for persistent infections and failed revision TKA. Considering the patient's quality of life, goals, and health status, this discussion should cover each procedure's risks and complications.

Forecasting the value of innovation in total knee arthroplasty care: A headroom approach

Purpose

Total knee arthroplasty (TKA) is the standard treatment of end-stage osteoarthritis. TKA is often used and, therefore, poses a healthcare and societal burden, which is likely to increase further. Headroom analyses evaluate a technology under development by making assumptions about its effectiveness. This article applies a headroom approach to forecast the potential value of innovations that improve TKA-related care in the Netherlands in terms of cost-effectiveness and surgeries avoided.

Methods

A state-transition model estimating lifetime direct health effects, healthcare- and societal costs and percentage of avoide d surgeries was developed. The model compared care as usual to five hypothetical interventions to calculate the headroom associated with (1) preventing the need for TKAs, (2) preventing the need for all TKA revisions, (3) postponing TKAs without quality-of-life loss, (4) preventing periprosthetic joint infections (PJIs) and (5) improving patient satisfaction.

Results

Preventing the need for all TKAs amounted to €43,076 of headroom. Preventing the need for TKA revisions amounted to €2276 (5.8% of surgeries avoided), postponing TKAs by 5 years amounted to €7634 (32.4% of surgeries avoided), preventing PJIs amounted to €1187 (1.4% of surgeries avoided) and improving patient satisfaction amounted to €16,622 (0% of surgeries avoided). The headroom of each hypothetical intervention was highest in younger populations (<50 years of age).

Conclusion

There is a headroom for improving TKA-related care. Innovations to avoid or postpone TKA (i.e., joint-preserving treatments) as well as those that improve patient satisfaction can be effective in maximizing the value for money and avoiding surgeries. Due to the decreasing average patient age, innovations to reduce revision rates and PJIs will become more valuable as these are most effective in younger patients. It is currently unclear how cost-effectiveness considerations should be traded off against the prevention of surgery to reduce the increasing burden on the healthcare system.

Level of Evidence

Level III economic evaluation/decision-analytic model.

Transfemoral amputation versus knee arthrodesis for failed total knee replacement: A systematic review of outcomes

BACKGROUND

The options available to salvage a failed total knee replacement (TKR) include transfemoral amputation (TFA) and knee arthrodesis (KA). This systematic review aims to evaluate outcomes following either TFA or KA, comparing ambulatory status, additional subsequent surgery, postoperative infection, pain, health-related quality of life (HRQoL), and mortality rate.

METHODS

A literature search was conducted in EMBASE, Ovid Medline, and PubMed. Only primary research studies were included and data were independently extracted using a standardized form. The methodological quality of the studies was evaluated using Newcastle-Ottawa Scale.

RESULTS

Forty-four papers were included, comprising 470 TFA and 1034 KA patients. The methodological quality of the studies was moderate. No TFA versus KA randomized controlled trials could be identified. Pooled data totals via subgroup analyses were performed, owing to inconsistent reporting methods in the included studies. Prosthesis use rate by TFA patients was 157/316 = 49.7%. Significant differences included that TFA patients had lower rates of ambulatory capacity than KA patients (139/294 = 45.6% versus 248/287 = 86.4%, p < 0.001), TFA ambulators were less likely to use an ambulatory aid (55/135 = 40.7% versus 167/232 = 72.0%, p < 0.001), and TFA was associated with a greater postoperative infection rate than KA (29/118 = 24.6% versus 129/650 = 17.2%, p = 0.054). There was a similar rate of revision surgery between TFA and KA (37/183 = 20.2% versus 145/780 = 18.6%, p = 0.612). Data on HRQoL for both TFA and KA were limited, contradictory, and heterogeneous.

CONCLUSION

No randomized controlled trials comparing TFA versus KA exist;therefore, current data likely reflects substantial selection bias. The currently available evidence suggests that KA patients are significantly more likely to achieve independent bipedal ambulation than TFA patients. In both treatment cohorts, subsequent infection and revision surgery remain a relatively common occurrence.

Failed 2-Stage Revision Knee Arthroplasty for Periprosthetic Joint Infection-Patient Characteristics and Outcomes

BACKGROUND

Chronic prosthetic joint infection (PJI) is most frequently treated with 2-stage revision in conjunction with antibiotic treatment. The aims of this study were 1) to investigate the characteristics of patients who have recurrent infection following 2-stage revision for PJI and 2) to identify risk factors associated with treatment failure.

METHODS

A multicenter retrospective review of 90 total knee arthroplasty (TKA) patients who underwent 2-stage revision for treatment of PJI from March 1, 2003 to July 31, 2019, and had recurrent PJI was conducted. The minimum follow-up was 12 months (median follow up of 2.4 years). Microorganisms, subsequent revision, PJI control status, and final joint status were collected. The infection-free survival after initial 2-stage revision was plotted utilizing the Kaplan-Meier method.

RESULTS

Mean survival time to reinfection was 21.3 months (range, 0.3 to 160.5). There were 14 recurrent infections that were acute PJIs treated with debridement, antibiotics, and implant retention (DAIR), while 76 were chronic and treated with repeat 2-stage revision. The most common pathogen identified for both index and recurrent PJI was coagulase-negative Staphylococci. Pathogen persistence was observed in 14 (22.2%) of recurrent PJIs. In total, 61 (67.8%) patients possessed a prosthetic reimplantation at their most recent follow-up, and 29 (35.6%) patients required intervention following repeat 2-stage.

CONCLUSION

Overall, 31.1% of the patients obtained infection control after treatment of a failed 2-stage revision due to PJI. The high rate of pathogen persistence and the relatively low survival time to recurrence suggests a need to more closely monitor PJIs cases within 2 years.

A comparison of outcomes for above-knee-amputation and arthrodesis for the chronically infected total knee arthroplasty: a systematic review

INTRODUCTION

Several strategies have been shown to have some efficacy in the chronically infected total knee arthroplasty (TKA): chronic antibiotic suppression, a second two-stage revision, arthrodesis, and above-the-knee amputation (AKA). We conducted a systematic review to determine the efficacy of these treatments in patients who had previously received a two-stage revision.

METHODS

A systematic review of the literature was performed which investigated PubMed, Embase, Scopus, and Web of Science Databases. Chronic infection was defined as a persistent infection of a TKA after a previous two-stage revision. Studies were independently evaluated by two reviewers. Quality appraisal was performed using MINORS Criteria.

RESULTS

14 studies were included for the final review. For chronically infected TKA, a second two-stage revision was often sufficient to control infection. If revision failed, the most common next procedure was either a repeat revision or AKA. AKA patients had less pain and higher quality of life scores compared to arthrodesis, but a higher five-year mortality rate.

DISCUSSION AND CONCLUSION

Chronic infection in TKA offers a multitude of challenges for orthopedic surgeons. We found that arthrodesis and AKA were not significantly different in rates of infection eradication or quality of life. We recommend clinicians to actively discuss options with patients to find a procedure most suitable for them.

The impact of knee arthrodesis on gait kinematics, muscle activity and patient-reported outcome

BACKGROUND

The aim of this retrospective study was to analyze gait kinematicsandoutcome parameters after knee arthrodesis.

METHODS

Fifteenpatients with a mean follow-up of 5.9 (range0.8-36) years after unilateral knee arthrodesis were included. A 3D gait analysis was performed and compared to a healthy control group of14patients. Comparative electromyography was performed bilaterally at the rectus femoris, vastuslateralis/medialisand tibialis anterior muscles. The assessment further included standardized outcome scores- Lower Extremity Functional Scale (LEFS) andShort Form Health Survey (SF-36).

RESULTS

The 3D analysis showed a significantly shortened stance phase (p = 0.000), an extended swing phase (p = 0.000), and an increased time per step (p = 0.009) for the operated side compared with thenonoperatedside. There were statistically significant differences in the extent of movement of the hips, knees and ankles among the operated andnonoperatedsides and the control group. For the mean EMG measurement, no significant difference was found between the healthy control group and the patients with arthrodesis.The average LEFSscorewas 27.5 ± 10.6out of a maximum of 80 points,and the mean physical total scale and mean emotional total scale scores for the SF-36 were 27.9 ± 8.5and 52.9 ± 9.9, respectively.

CONCLUSIONS

Arthrodesis of the knee joint causes significant kinematic changes in gait pattern,and patients achieve poor results in subjective and functional outcomes(SF- 36, LEFS).Arthrodesis ensures that the extremities are preserved and can enable walking, but it must be viewed as a severe handicap for the patient.

Repeat two-stage exchange arthroplasty for recurrent periprosthetic hip or knee infection: what are the chances for success?

INTRODUCTION

Two-stage revision is a frequently chosen approach to treat chronic periprosthetic joint infection (PJI). However, management of recurrent infection after a two-stage exchange remains debated and the outcome of a repeat two-stage procedure is unclear. This study investigates the success rates of repeat two-stage exchange arthroplasty and analyzes possible risk factors for failure.

MATERIALS AND METHODS

We retrospectively identified 55 patients (23 hips, 32 knees) who were treated with repeat resection arthroplasty and planned delayed reimplantation for recurrent periprosthetic joint infection between 2010 and 2019 after a prior two-stage revision at the same institution. The minimum follow-up was 12 months with a median follow-up time of 34 months (IQR 22-51). The infection-free survival, associated revision surgeries, and potential risk factors for further revision were analyzed using Kaplan-Meier survival curves and comparative non-parametric testing.

RESULTS

78% (43/55) underwent reimplantation after a repeat implant removal. Of those who completed the second-stage surgery, 37% (16/43) underwent additional revision for infection and 14% (6/55) underwent amputation. The reinfection-free implant survivorship amounted to 77% (95% CI 64-89%) after 1 year and 38% (95% CI 18-57%) after 5 years. Patients with a higher comorbidity score were less likely to undergo second-stage reimplantation (median 5 vs. 3, p = 0.034). Furthermore, obese patients (p = 0.026, Fisher's exact test) and diabetics (p < 0.001, log-rank test) had a higher risk for further infection. Most commonly cultures yielded polymicrobial growth at the repeat two-stage exchange (27%, 15/55) and at re-reinfection (32%, 9/28). Pathogen persistence was observed in 21% (6/28) of re-reinfected patients.

CONCLUSION

The success rates after repeat two-stage exchange arthroplasty are low. Patients must be counseled accordingly and different modes of treatment should be considered.

Universal Screening for Malnutrition Prior to Total Knee Arthroplasty Is Cost-Effective: A Markov Analysis

BACKGROUND

Patients undergoing total knee arthroplasty (TKA) who have malnutrition possess an increased risk of periprosthetic joint infection (PJI). Although malnutrition screening and intervention may decrease the risk of PJI, it utilizes healthcare resources. To date, no cost-effectiveness analyses have been performed on the screening and treatment of malnutrition prior to TKA.

METHODS

A Markov model projecting lifetime costs and quality-adjusted life years (QALYs) was built to determine the cost-effectiveness of malnutrition screening and intervention for TKA patients from a societal perspective. Costs, health state utilities, and state transition probabilities were obtained from previously published literature, hospital costs at our institution, and expert opinions. Two important assumptions included that 30% of patients would be malnourished and that a malnutrition intervention would be 50% effective. The primary outcome of this study was the incremental cost-effectiveness ratio, with a willingness-to-pay threshold of $100,000 per QALY. One-way and two-way sensitivity analyses were performed to evaluate model parameter assumptions.

RESULTS

When using the base case values, universal malnutrition screening and intervention was cost-effective compared to no malnutrition screening or intervention, with an incremental cost-effectiveness ratio of $6,454 per QALY. Universal screening and intervention remained cost-effective, provided the cost of screening remained less than $3,373, the cost of nutritional intervention remained less than $12,042, the prevalence of malnutrition among surgical candidates was higher than 2%, and the risk of PJI among patients with malnutrition was greater than 1%.

CONCLUSION

Universal preoperative malnutrition screening and intervention among TKA candidates is cost-effective at parameters encountered in clinical practice. Nutritional optimization programs should be considered to facilitate malnutrition screening and intervention and future studies should evaluate their efficacy at lowering PJI risk.

Above-Knee Amputation After Total Knee Replacement Infection: The Unfortunate End of an Odyssey

Total knee replacement is the gold standard for the surgical treatment of late-stage symptomatic knee osteoarthritis when conservative measures have not alleviated the problem. However, as with any surgery, there are potential dangers and complications. Of these, infection is one of the most severe and may lead to life-changing outcomes for the patient. In this case report, a patient with a history of infected primary total knee arthroplasty and numerous attempts to eradicate the patient's infection is presented. After two unsuccessful two-stage revisions, and although arthrodesis was discussed and suggested, an above-knee amputation was finally applied to our patient.

National Decline in Knee Fusions Performed for Salvage of Chronic Periprosthetic Total Knee Infections

The primary purpose of this study was to study and compare rates of two salvage operations for patients with chronically infected total knee arthroplasties: (1) knee arthrodesis and (2) above knee amputation (AKA). An analysis was performed comparing the inpatient hospital characteristics and complications between the two procedures. Secondarily, we presented rates of all surgically treated periprosthetic total knee infections over a 6-year period. Using the Nationwide Inpatient Sample, we identified all patients with a periprosthetic infection (International Classification of Diseases, Ninth Revision [ICD-9] 996.66) from 2009 to 2014. Subsequently, we identified surgically treated total knee infections through the following ICD-9 codes: 00.80 (all component revision), 00.84 (liner exchange), 80.06 (removal of prosthesis), 84.17 (AKA), and 81.22 (knee fusion). From 2009 to 2014, the annual incidence of surgically treated total knee periprosthetic infections increased by 34.9% nationally, while the annual incidence of primary total knees increased by only 13.9%. Salvage operations (AKA and knee fusion) represented 5.8% of all surgically treated infections. The rate of knee fusions decreased from 1.9% of surgically treated infections in 2009 to 1.4% in 2014 (p < 0.05), while the rate of AKA stayed steady at 4.5% of cases over the 6-year period. Length of stay was significantly shorter in the knee fusion group (7.9 vs. 10.8 days, p < 0.05), but total hospital costs were higher (33,016 vs. 24,933, p < 0.05). In the multivariable adjusted model, patients undergoing knee fusion had significantly decreased odds of being discharged to skilled nursing facility (odds ratio: 0.42, 95% confidence interval: 0.31-0.58). The annual incidence of surgically treated periprosthetic total knee infections is increasing. The rate of knee arthrodesis for chronic periprosthetic total knee infections is decreasing. Reasons for this downward trend in knee fusions should be evaluated carefully as knee fusions have shown to have the potential advantage of improved mobility and decreased patient morbidity for chronic PJI. The level of evidence is III.

Contemporary Outcomes of Transfemoral Amputation After Total Knee Arthroplasty

BACKGROUND

Transfemoral amputation (TFA) is a salvage procedure for unreconstructable failed total knee arthroplasty (TKA). Prior studies have reported poor outcomes, patient survival, and prosthetic use. The purpose of this study was to analyze patient outcomes and prosthetic utilization in a contemporary group of patients undergoing TFA in the setting of a TKA.

METHODS

We reviewed 112 patients undergoing TFA with a prior TKA. Indications for amputation and postoperative functional measures were captured through chart review. Patients were contacted by survey to assess the quality of life. The mean follow-up after TFA was 4 years.

RESULTS

Amputations were performed for a chronically infected TKA (n = 87, 78%) and an ischemic limb without signs of an infected TKA (n = 22, 20%). The 10-year survival after TFA was 21%. Of the patients not lost to follow-up, 53 (47%) patients were fitted for a prosthesis. Patients who underwent a TFA after the year 2000 were more likely to be fit for a prosthesis (odds ratio 7.27, P < .01); however, patients were likely to be ambulatory before TFA than after TFA (odds ratio 3.68, P < .01). After TFA, the mean 12-Item Short Form Survey scores for the mental and physical components were 54 ± 13 and 34 ± 7, with no difference in scores between patients fitted for a prosthesis and those who were not (P > .05).

CONCLUSION

Patients undergoing a TFA after TKA due to failure of the TKA are more likely to be fit for a prosthesis; however, they reported no better quality of life and satisfaction compared with patients not fit for a prosthesis.

LEVELS OF EVIDENCE

Level III, Therapeutic.

High revision rates following repeat septic revision after failed one-stage exchange for periprosthetic joint infection in total knee arthroplasty

AIMS

The outcome of repeat septic revision after a failed one-stage exchange for periprosthetic joint infection (PJI) in total knee arthroplasty (TKA) remains unknown. The aim of this study was to report the infection-free and all-cause revision-free survival of repeat septic revision after a failed one-stage exchange, and to determine whether the Musculoskeletal Infection Society (MSIS) stage is associated with subsequent infection-related failure.

METHODS

We retrospectively reviewed all repeat septic revision TKAs which were undertaken after a failed one-stage exchange between 2004 and 2017. A total of 33 repeat septic revisions (29 one-stage and four two-stage) met the inclusion criteria. The mean follow-up from repeat septic revision was 68.2 months (8.0 months to 16.1 years). The proportion of patients who had a subsequent infection-related failure and all-cause revision was reported and Kaplan-Meier survival for these endpoints was determined. Patients were categorized according to the MSIS staging system, and the association with subsequent infection was analyzed.

RESULTS

At the most recent follow-up, 17 repeat septic revisions (52%) had a subsequent infection-related failure and the five-year infection-free survival was 59% (95% confidence interval (CI) 39 to 74). A total of 19 underwent a subsequent all-cause revision (58%) and the five-year all-cause revision-free survival was 47% (95% CI 28 to 64). The most common indication for the first subsequent aseptic revision was loosening. The MSIS stage of the host status (p = 0.663) and limb status (p = 1.000) were not significantly associated with subsequent infection-related failure.

CONCLUSION

Repeat septic revision after a failed one-stage exchange TKA for PJI is associated with a high rate of subsequent infection-related failure and all-cause revision. Patients should be counselled appropriately to manage expectations. The host and limb status according to the MSIS staging system were not associated with subsequent infection-related failure. Cite this article: Bone Joint J 2022;104-B(3):386-393.

Outcomes of Modular Knee Arthrodesis for Challenging Periprosthetic Joint Infections

Background

Methods

Results

Discussion

Classification and management options for prosthetic joint infection

Periprosthetic joint infection (PJI) is one of the major complications following arthroplasty implantation. Management of PJIs is a challenge for surgeons and various classification systems have been introduced, which consider variables such as onset of symptoms, pathogenesis and clinical manifestation. In an attempt to overcome the shortcomings which may limit their usefulness in borderline cases, a new classification system focusing on the topography of the infectious process has been proposed. This theory relies on the identification of the exact location of the bacterial colonization thus allowing to decide between a conservative or a more radical intervention irrespectively of the timing. The use of nuclear medicine device like radiolabelled white blood cells (WBC) scan could lead the path in identifying pathogenetic processes and their exact location thus guiding orthopaedic surgeons to the most appropriate diagnosis and treatment options. Currently management relies on debridement, antibiotics and implant retention (DAIR), which is traditionally performed at early stages, 1- or 2-stage revision arthroplasty which is commonly limited to chronic cases. Reports have demonstrated similar rates of infection recurrence following one and two-stage revisions, and the use of one-stage revision surgery is gaining popularity. More recently, satisfying results following partial implant retention during revision total arthroplasty for septic failures have been reported. In addition, in severe cases, definitive articulating antibiotic spacer, excision arthroplasty, arthrodesis or amputation can be performed.

Diagnosis and management of infected arthroplasty

Periprosthetic joint infection (PJI) is one of the most dreadful complications after THA and TKA. Though prevention is of utmost importance in PJI management, the last decade has seen many remarkable developments in PJI diagnosis, including the introduction of several standardized PJI diagnostic definitions and biomarkers. Depending on the specific clinical situation, a myriad of treatment options for PJI are offered. Our review aims to summarize the pertinent information on PJI diagnosis and synthesize literature on the different treatment methods currently used in clinical practice. One of the most accepted PJI diagnostic definitions was developed by the Musculoskeletal Infection Society (MSIS) in 2011, later modified in the 2013 International Consensus Meeting (ICM). After promising results from studies, alpha-defensins and D-dimer were recently incorporated into the 2018 ICM PJI definition. The management choices for PJI include irrigation and debridement (DAIR), one-stage exchange arthroplasty, or two-stage exchange arthroplasty, to name a few. While two-stage revision has traditionally been the treatment of choice in the United States, there has been a growing body of evidence framing one-stage revision as a comparable choice. One-stage revision should be offered in patients meeting strict selection criteria: no sinus tract, proper soft tissue available for wound closure, appropriate bone stock, a favorable identifiable organism with encouraging antibiotic sensitivities (for cement and oral suppression later), and robust immunological status. DAIR can be considered in case of early infections with sensitive infecting organisms. Patients with multiple unsuccessful revisions or those who refuse further surgical intervention for PJI can be offered antibiotic suppression. If nothing seems to work, salvage procedures (resection arthroplasty and arthrodesis) are available as a last resort. Further research is encouraged to improve on diagnostic capabilities and develop evidence on the best treatment of choice for PJI.

Current Insights in the Evaluation and Treatment of Infected Total Knee Arthroplasty

Total knee arthroplasty is a widely successful procedure, but a small percentage of patients have a postoperative course complicated by periprosthetic joint infection (PJI). PJI is a difficult problem to diagnose and to treat, and the management of PJI differs, depending on the acuity of the infection. This paper discusses the established and newer technologies developed for the diagnosis of PJI as well as different treatment considerations and surgical solutions currently available.

Modular knee arthrodesis secures limb, mobility, improves quality of life, and leads to high infection control in periprosthetic knee infection, when revision knee arthroplasty is not an option

INTRODUCTION

This study compared the outcome of knee arthrodesis versus hinged total knee arthroplasty (TKA) in patients suffering from periprosthetic joint infection (PJI).

METHODS

104 patients with PJI were treated using a two-stage exchange of failed TKA. In case of non reconstructable bone loss or loss of extension mechanism, a modular intramedullary arthrodesis nail was used for reimplantation [Knee Arthrodesis Module (KAM); n = 52]. The control group was retrospectively matched treated using a hinged revision TKA [Rotating Hinge Knee (RHK); n = 52]. PJI remission rates, functional outcome (WOMAC; KSS) and quality of life (SF-12), as well as comorbidities and pain were evaluated.

RESULTS

Mean age was 72.5 years. Charlson Comorbidity Index was higher in the KAM group (3.3 vs. 2.8). PJI remission rate was 89.4% (88.5% vs. 90.4%, respectively). In case of reinfection, implant retention was mostly possible in the RHK group (7.7%), whereas amputations were mostly performed in the KAM group (9.6%). Significant pain reduction (VAS 7.9-2.8) was achieved in both groups. Walking distance was significantly reduced in the KAM groups versus the RHK group (504 vs. 1064 m). WOMAC and KSS function scores were significantly reduced in the KAM group (25 vs. 40 and 35 vs. 64). Only moderate reduction in quality of life in the KAM group was observed (SF-12 physical: 34 vs. 40; SF-12 mental: 51 vs. 56) respectively.

CONCLUSIONS

Arthrodesis using a modular intramedullary nail is an alternative for limb salvage, pain reduction, and preservation of quality of life and everyday mobility, when revision TKA is not an option. This study presents the largest number of case, comparing the outcome after performing an arthrodesis versus hinged TKA after septic failed TKA.

Functional Outcome of Patients Undergoing Knee Arthrodesis after Infected Total Arthroplasty

Objective  Retrospectively assess the functional outcome of patients undergoing arthrodesis after septic failure of total knee arthroplasty. Methods  Eighteen patients were evaluated, with a mean time of 3.7 years of follow-up. Arthrodesis surgery was performed using a narrow anterior dynamic compression plate, and medial or external fixator in two planes of the joint (Orthofix Bone Growth Therapy, Lewisville, TS, USA), at the surgeon's discretion. Results  The most frequent pathogen found was Staphylococcus aureus methicillin sensitive (38.9%). The mean lower limb discrepancy was 3.63 cm. The mean knee society score was 68 points. According to the visual analog scale for pain, 44% of the patients had a 0 score at the time of assessment, and 22.2% were very dissatisfied, despite the bone healing achieved. Patients were assessed for the ability to walk with or without assistance. Conclusion  Knee arthrodesis surgery was effective in controlling the infectious process and decreasing pain complaints, but satisfaction with the procedure was low.

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.

Two-stage arthrodesis for complex, failed, infected total knee arthroplasty

AIMS

Arthrodesis is rarely used as a salvage procedure for patients with a chronically infected total knee arthroplasty (TKA), and little information is available about the outcome. The aim of this study was to assess the reliability, durability, and safety of this procedure as the definitive treatment for complex, chronically infected TKA, in a current series of patients.

METHODS

We retrospectively identified 41 patients (41 TKAs) with a complex infected TKA, who were treated between 2002 and 2016 using a deliberate, two-stage knee arthrodesis. Their mean age was 64 years (34 to 88) and their mean body mass index (BMI) was 39 kg/m² (25 to 79). The mean follow-up was four years (2 to 9). The extensor mechanism (EM) was deficient in 27 patients (66%) and flap cover was required in 14 (34%). Most patients were host grade B (56%) or C (29%), and limb grade 3 (71%), according to the classification of McPherson et al. A total of 12 patients (29%) had polymicrobial infections and 20 (49%) had multi-drug resistant organisms; fixation involved an intramedullary nail in 25 (61%), an external fixator in ten (24%), and dual plates in six (15%).

RESULTS

Survivorship free from amputation, persistent infection, and reoperation, other than removal of an external fixator, at five years was 95% (95% confidence interval (CI) 89% to 100%), 85% (95% CI 75% to 95%), and 64% (95% CI 46% to 82%), respectively. Reoperation, other than removal of an external fixator, occurred in 13 patients (32%). After the initial treatment, radiological nonunion developed in ten knees (24%). Nonunion was significantly correlated with persistent infection (p = 0.006) and external fixation (p = 0.005). Of those patients who achieved limb salvage, 34 (87%) remained mobile and 31 (79%) had 'absent' or 'minimal' pain ratings.

CONCLUSION

Knee arthrodesis using a two-stage protocol achieved a survivorship free from amputation for persistent infection of 95% at five years with 87% of patients were mobile at final follow-up. However, early reoperation was common (32%). This is not surprising as this series included worst-case infected TKAs in which two-thirds of the patients had a disrupted EM, one-third required flap cover, and most had polymicrobial or multi-drug resistant organisms. Cite this article: Bone Joint J 2020;102-B(6 Supple A):170-175.

High Rate of Fusion but High Complication Rate After Knee Arthrodesis for Infected Revision Total Knee Replacement

BACKGROUND

Knee arthrodesis is a demanding technique regarding difficulties to achieve bone fusion, control of infection and its associated complications. The purpose of this study was to evaluate if knee arthrodesis should still be indicated after failed revision total knee replacement.

METHODS

This was a retrospective study of 45 patients. Age, gender, follow-up, pathogens, Charlson comorbidity index, time from primary arthroplasty to arthrodesis, number of previous procedures, surgical technique, functional capability assessed by the SF-12 score, limb-length discrepancy after arthrodesis, presence of radiographic knee fusion, and complications were recorded.

RESULTS

The mean age at the time of operation was 72 years. 29% of patients were men, 71% were women, and the mean follow-up was 8.5 years. The average Charlson comorbidity index was 4.5. The most common microorganisms isolated were Staphylococcus epidermidis (29%), Staphylococcus aureus (22%), and Pseudomonas aeruginosa (15%). In 20% of patients, no microorganism was identified, and in 37% of patients the infection was polymicrobial. Time from primary total knee arthroplasty to arthrodesis was 55 months, and patients underwent a mean of 3.9 previous surgeries. The surgical technique used was an intramedullary long nail in 95.5%. Functionally, 93.3% of patients walked with weight bearing. The SF-12 was higher after arthrodesis (p < 0.05). Mean limb length discrepancy was 2.4 cm. Among the group treated with long intramedullary nailing, 91.1% obtained tibiofemoral fusion. Complications occurred in 37.6% of patients.

CONCLUSIONS

Knee arthrodesis with a long intramedullary nail after failed infected revision total knee replacement has a high rate of fusion, but the complication rate is high.

Uniplanar versus biplanar monolateral external fixator knee arthrodesis after end-stage failed infected total knee arthroplasty: a comparative study

BACKGROUND

External fixator knee arthrodesis is a salvage procedure used primarily in cases of end-stage infected total knee replacement (iTKR). Stable fixation combined with bone-end compression is essential to achieve knee fusion, but providing sufficient stability can be challenging in the presence of severe bone loss. Our hypothesis is that using an external fixation biplanar configuration would bring about a fusion rate superior to that of a monolateral frame.

METHODS

This study compares outcomes of biplanar external fixator knee fusion due to non-revisable iTKR with those of a historical cohort control study with patients managed with a monoplanar configuration. Primary endpoints were fusion rate, time to achieve bone fusion and infection eradication rate. Limb-length discrepancy, pain level, patient satisfaction and health-related quality of life were evaluated.

RESULTS

A total of 29 knee fusion cases were included. In the biplanar group, infection was eradicated in 100% of the patients and fusion was achieved in all cases within an average of 5.24 months. In comparison, in the monolateral group, infection was eradicated in 86% of the cases and fusion was achieved in 81% of the patients after a mean of 10.3 months (p < 0.05). In both groups, postoperative pain was mild and patients expressed a high degree of satisfaction once fusion was achieved.

CONCLUSIONS

According to our data, external fixation knee fusion is a useful limb-salvage procedure in end-stage cases of knee PJI. We conclude that a biplanar configuration can halve the time required to achieve solid bone fusion in such a complex scenario.

Peri-implant fracture after dual-plating knee arthrodesis for failed total knee arthroplasty: case series

Knee arthrodesis is an option in the setting of failed total knee arthroplasty. Dual-plate fixation is a described technique to obtain knee fusion in this scenario. Literature on the complications of knee arthrodesis with dual-plate constructs is limited. We present 3 cases who underwent dual-plate knee arthrodesis complicated by peri-implant femur fracture.

Next-Generation Sequencing vs Culture-Based Methods for Diagnosing Periprosthetic Joint Infection After Total Knee Arthroplasty: A Cost-Effectiveness Analysis

BACKGROUND

Periprosthetic joint infection (PJI) after total knee arthroplasty is challenging to diagnose. Compared with culture-based techniques, next-generation sequencing (NGS) is more sensitive for identifying organisms but is also less specific and more expensive. To date, there has been no study comparing the cost-effectiveness of these two methods to diagnose PJI after total knee arthroplasty.

METHODS

A Markov, state-transition model projecting lifetime costs and quality-adjusted life years (QALYs) was constructed to determine the cost-effectiveness from a societal perspective. The primary outcome was incremental cost-effectiveness ratio, with a willingness-to-pay threshold of $100,000/QALY. Sensitivity analyses were performed to evaluate parameter assumptions.

RESULTS

At our base case values, culture was not determined to be cost-effective compared to NGS, with an incremental cost-effectiveness ratio of $422,784 per QALY. One-way sensitivity analyses found NGS to be the cost-effective choice above a pretest probability of 45.5% for PJI. In addition, NGS was cost-effective if its sensitivity was greater than 70.0% and its specificity greater than 94.1%. Two-way sensitivity analyses revealed that the pretest probability and test performance parameters (sensitivity and specificity) were the largest factors for identifying whether a particular strategy was cost-effective.

CONCLUSION

The results of our model suggest that the cost-effectiveness of NGS to diagnose PJI depends primarily on the pretest probability of PJI and the performance characteristics of the NGS technology. Our results are consistent with the idea that NGS should be reserved for clinical contexts with a high pretest probability of PJI. Further study is required to determine the indications and subgroups for which NGS offers clinical benefit.

Clinical Evaluation of Alpha Defensin Test Following Staged Treatment of Prosthetic Joint Infections

BACKGROUND

Diagnosing persistent infection following staged treatment of prosthetic joint infection (PJI) is challenging. The alpha defensin (AD) test has been shown to be an accurate diagnostic test for the primary diagnosis PJI but has limited evaluation for use following a staged treatment of PJI. The goal of this study was to evaluate the diagnostic accuracy of AD testing following staged treatment of PJI before reimplantation surgery and to determine if negative AD test predicted success following reimplantation using Delphi Criteria at time of last follow-up.

METHODS

Patients who underwent AD testing prior to reimplantation after staged treatment of PJI (n = 52) were reviewed. Preoperative data (AD result, synovial fluid [SF], C-reactive protein level [mg/L], SF culture, SF white blood cell count, % of polymorphonuclear lymphocytes, serum C-reactive protein/erythrocyte sedimentation rate) and intraoperative data (purulence and tissue culture) were reviewed and used to classify patients using 2018 Musculoskeletal Infectious Disease Society criteria for infection, which was then used as a gold standard test to calculate diagnostic accuracy. Chart review was used to determine if patients who underwent reimplantation surgery would go on to treatment failure as defined by Delphi Criteria.

RESULTS

The sensitivity and specificity of AD test result as compared with Musculoskeletal Infectious Disease Society criteria in diagnosing PJI was calculated to be 71% and 97.78%. Positive predictive value was calculated to be 83.3%, and negative predictive value was calculated to be 95.65%. Patients who underwent reimplantation (46/52 patients) all had negative AD test results, and 9/46 or 19.5% would have treatment failure as defined by the Delphi Criteria with an average follow-up of 588 days.

CONCLUSION

AD demonstrates high specificity and negative predictive value, with low sensitivity when utilized after staged treatment of PJI. Further investigation of this and other diagnostic tests following staged treatment of PJI is needed. Additionally, validated criteria used to identify persistent infection following staged treatment of PJI are required.

[Modular arthrodesis system TITAN (KAM-TITAN) after failed revision total knee arthroplasty : Operative technique and clinical experience]

OBJECTIVE

Restoration of a painless, weight-bearing extremity with a modular knee arthrodesis system based on a cementless modular revision stem for rotationally stable, diaphyseal anchorage.

INDICATIONS

Severe bone loss and compromised soft tissue after failed total knee arthroplasty, two-stage revisions and non-reconstructible knee extensor mechanism deficiency.

CONTRAINDICATIONS

Extensive osteolysis preventing diaphyseal anchorage of the prosthesis. Contralateral arthrodesis of the knee joint and/or ipsilateral arthrodesis of the hip joint and contralateral lower extremity amputation.

SURGICAL TECHNIQUE

In revision cases, removal of the total knee arthroplasty, spacer, the bone cement and all intramedullary granulation tissue. Reaming the medullary cavity with intramedullary reamers to cortical contact. Restoring leg length and rotation with trial implants. After implantation of the femoral and tibial stems, placing and tensioning of the rotationally aligned coupling elements.

POSTOPERATIVE MANAGEMENT

Mobilization on two forearm crutches from postoperative day 1. Removal of the Redon drains after 48 h. Partial weight bearing of 20 kg for 6 weeks postoperatively. If plain radiographs show unchanged seating of the prosthesis after 6 weeks, loading can be increased by 10 kg per week until full weight bearing is achieved.

RESULTS

Between 2007 and 2012 clinical data were collected and analyzed retrospectively. A total of 27 patients had been treated within a two-stage exchange procedure with implantation of a modular intramedullary arthodesis nail TITAN (KAM-TITAN). The mean follow-up was 30.9 ± 12.0 months. A functional evaluation was performed using the Oxford Knee Score (OKS). The analyzed patients showed a mean score of 39.2 ± 8.3. To determine the pain level the Visual Analog Scale (VAS) for pain was used and showed a mean score of 2.9 ± 1.3. The rate of definitely free of infection (using Laffer criteria) at last follow-up was 85.2%.

Mycobacterium tuberculosis as a Cause of Periprosthetic Joint Infection After Total Knee Arthroplasty: A Review of the Literature

Total knee arthroplasty (TKA) has become one of the most popular and successful surgeries performed in the world. Infection remains one of the most dreaded complications following TKA, and while rare, tuberculosis as a microbial etiology remains difficult to both diagnose and treat. A review was performed using PubMed, the Cochrane Database of Systematic Reviews, and EMBASE to identify literature pertinent to Mycobacterium tuberculosis infection, TKAs, periprosthetic joint infections, and any combination of the three. The diagnosis of tuberculosis infection after TKA is difficult due to nonspecific signs and symptoms and diagnostic testing. The surgeon should use a comprehensive approach to incorporate the patient's medical history, physical exam, and blood and imaging diagnostics. Among these, bacterial culture and histopathological examination remain the gold standard of diagnosis, but Polymerase chain reaction technology offers another, more sensitive and rapid option. Treatment strategy centers around on the cornerstone of anti-tuberculosis medical therapy and surgery depending on the clinical situation. While there is a lack of primary literature and standardized guidelines for the diagnosis and treatment of tuberculosis infection after TKA, the overarching principles of the treatment of tuberculosis and the treatment of the periprosthetic infection can be implemented together. There remains room for original research and improvements in both diagnostic testing and treatment.

Outcome of Irrigation and Debridement after Failed Two-Stage Reimplantation for Periprosthetic Joint Infection

Introduction

Two-stage revision is the gold standard for the treatment of deep implant infection after knee or hip arthroplasty. Irrigation and debridement may be a treatment option for failed 2-stage revisions in cases where a reinfection occurs within 30 days or the symptoms exist not longer than 3 weeks and is appealing because of its low morbidity. We determined the incidence of recurrent infections following irrigation and debridement for failed two-stage revision hip and knee arthroplasty.

Methods

We performed a single center retrospective review of periprosthetic hip and knee infections treated with a two-stage procedure from 2002 to 2010. All patients that subsequently underwent irrigation and debridement for a subsequent infection were selected for the current study.

Results

440 two-stage revisions were performed between 2002 and 2010. Fifty-one two-stage revisions failed (11.6%). Nineteen failed two-stage revisions were treated with irrigation and debridement; 12 (63.2%) patients remained free of infection at follow-up (mean follow-up: 39 months; range, 24-90 months), infection persisted in 6 patients (31.6%), and 1 patient died (5.3%).

Conclusions

Success rates of irrigation and debridement for failed two-stage procedures are similar to the success rates of irrigation and debridement in primary implant infections. According to the current paper, irrigation and debridement are an acceptable treatment for acute reinfections after failed two-stage revision if performed within the first 30 postoperative days after failed two-stage procedure or if symptoms are present for less than 3 weeks in the presence of a susceptible organism.

Re-infection rates and clinical outcomes following arthrodesis with intramedullary nail and external fixator for infected knee prosthesis: a systematic review and meta-analysis

Background

Knee arthrodesis with intramedullary (IM) nail or external fixator (EF) is the most reliable therapeutic option to achieve definitive infection control in patients with septic failure of total knee arthroplasty (TKA). The first aim of this study was to compare re-infection rates following knee arthrodesis for periprosthetic joint infection (PJI) with IM nail or EF. The second aim was to compare rates of radiographic union, complication, and re-operation as well as clinical outcomes.

Methods

A systematic search was performed in electronic databases for longitudinal studies of PJIs (minimum ten patients; minimum follow-up = 1 year) treated by knee arthrodesis with IM nail or EF. Studies were also required to report the rate of re-infection as an outcome measure. Eligible studies were meta-analyzed using random-effect models.

Results

The rate (95% confidence intervals) of re-infection was 10.6% (95% CI 7.3 to 14.0) in IM nail arthrodesis studies. The corresponding re-infection rate for EF was 5.4% (95% CI 1.7 to 9.1). This difference was significant (p = 0.009). The use of IM nail resulted in more advantages than EF for frequency of major complications and limb shortening. Other postoperative clinical and radiographic outcomes were similar for both surgical strategies.

Conclusions

The available evidence from the aggregate published data suggests that knee arthrodesis with EF in the specific context of PJI has a reduced risk of re-infection in comparison with the IM nail strategy. The use of IM nail is more effective for the complication rate and shortening of the affected limb.

Clinical Outcome of Massive Endoprostheses Used for Managing Periprosthetic Joint Infections of the Hip and Knee

BACKGROUND

Endoprosthetic replacement (EPR) is an option for management of massive bone loss resulting from infection around failed lower limb implants. The aim of this study is to determine the mid-term outcome of EPRs performed in the treatment of periprosthetic joint infection (PJI) and infected failed osteosyntheses around the hip and knee joint and identify factors that influence it.

METHODS

We retrospectively reviewed all hip and knee EPRs performed between 2007 and 2014 for the management of chronic infection following complex arthroplasty or fracture fixation. Data recorded included indication for EPR, number of previous surgeries, comorbidities, and organism identified. Outcome measures included PJI eradication rate, complications, implant survival, mortality, and functional outcome (Oxford Hip or Knee Score).

RESULTS

Sixty-nine EPRs (29 knees and 40 hips) were performed with a mean age of 68 years (43-92). Polymicrobial growth was detected in 36% of cases, followed by coagulase-negative staphylococci (28%) and Staphylococcus aureus (10%). Recurrence of infection occurred in 19 patients (28%): 5 were treated with irrigation and debridement, 5 with revision, 1 with above-knee amputation, and 8 remain on long-term antibiotics. PJI eradication was achieved in 50 patients (72%); the chance of PJI eradication was greater in hips (83%) than in knees (59%) (P = .038). The 5-year implant survivorship was 81% (95% confidence interval 74-88). The mean Oxford Hip Score and Oxford Knee Score were 22 (4-39) and 21 (6-43), respectively.

CONCLUSION

This study supports the use of EPRs for eradication of PJI in complex, multiply revised cases. We describe PJI eradication rate of 72% with acceptable functional outcome.

Knee arthrodesis versus above-the-knee amputation after septic failure of revision total knee arthroplasty: comparison of functional outcome and complication rates

BACKGROUND

After septic failure of total knee arthroplasty (TKA) and multiple revision operations resulting in impaired function, bone and/or soft-tissue damage a reconstruction with a revision arthroplasty might be impossible. Salvage procedures to regain mobility and quality of life are an above-the-knee amputation or knee arthrodesis. The decision process for the patient and surgeon is difficult and data comparing arthrodesis versus amputation in terms of function and quality of life are scarce. The purpose of this study was to analyse and compare the specific complications, functional outcome and quality of life of above-the-knee amputation (AKA) and modular knee-arthrodesis (MKA) after septic failure of total knee arthroplasty.

METHODS

Eighty-one patients treated with MKA and 32 patients treated with AKA after septic failure of TKA between 2003 and 2012 were included in this cohort study. Demographic data, comorbidities, pathogens and complications such as re-infection, implant-failure or revision surgeries were recorded in 55MKA and 20AKA patients. Functional outcome with use of the Lower-Extremity-Functional-Score (LEFS) and the patients reported general health status (SF-12-questionnaire) was recorded after a mean interval of 55 months.

RESULTS

A major complication occurred in more than one-third of the cases after MKA and AKA, whereas recurrence of infection was with 22% after MKA and 35% after AKA the most common complication. Patients with AKA and MKA showed a comparable functional outcome with a mean LEFS score of 37 and 28 respectively (p = 0.181). Correspondingly, a comparable physical quality of life with a mean physical SF-12 of 36 for AKA patients and a mean score of 30 for MKA patients was observed (p = 0.080). Notably, ten AKA patients that could be fitted with a microprocessor-controlled-knee-joint demonstrated with a mean LEFS of 56 a significantly better functional outcome than other amputee patients (p < 0.01) or MKA patients (p < 0.01).

CONCLUSION

Naturally, the decision process for the treatment of desolate situations of septic failures following revision knee arthroplasty is depending on various factors. Nevertheless, the amputation should be considered as an option in patients with a good physical and mental condition.

Two-stage knee arthrodesis with a modular intramedullary nail due to septic failure of revision total knee arthroplasty with extensor mechanism deficiency

BACKGROUND

Periprosthetic joint infection is a serious complication and reconstruction after failed revision total knee arthroplasty with significant bone loss and compromised soft-tissues can be challenging. Objective of this study was to assess clinical and functional results, implant survival and infection recurrence rates in patients treated with two-stage arthrodesis after failed revision TKA with extensor mechanism deficiencies due to PJI, and to identify the factors that affect outcomes after surgery.

METHODS

Thirty seven patients with PJI treated within a two-stage exchange and reimplantation of an arthrodesis nail between 2008 and 2014 were included. Systemic and local risk factors were graded preoperatively according to McPherson et al. All patients were treated according to a structured treatment algorithm. Clinical and functional evaluation was performed using the Oxford Knee Score and the Visual Analogue Scale.

RESULTS

Thirty two of 37 patients (86.5%) were graded as free of infection. Five patients (13.5%) had recurrent infection after arthrodesis with the need of revision surgery. Mean leg-length discrepancy was 2.2cm. The mean VAS for pain was three, the mean Oxford Knee Score was 38±9. Total implant survival at a 74month follow-up was 74.3% (95% CI: 45.4 to 91.1%), as determined by Kaplan-Meier survival curves. Local McPherson Score, as well as number of revisions was found to be of significant influence to the survival rate.

CONCLUSIONS

Septic failure of revision knee arthroplasty can be effectively treated with two-stage arthrodesis using a modular intramedullary nail, providing a stable and painless limb with satisfactory functional results and acceptable infection eradication rates.

Revision Knee Arthroplasty in Patients with Inherited Bleeding Disorders: A Single-Center Experience

Background

The results of total knee arthroplasty (TKA) in patients with inherited bleeding disorders (IBDs) are poorer when compared with those in the general population, with a notably higher risk of complications and higher revision rates. Thus, revision procedures are becoming a growing concern in this group of patients. The aim of this study was to evaluate the results of revision TKA in patients with IBD.

Material/Methods

A retrospective cohort study with longitudinal assessment of hemophilia patients scheduled for revision TKA between January 2010 and September 2015 was performed. The clinical status of the patients was assessed based on the Knee Society Score, and the Numeric Rating Scale was used to assess knee pain severity and patient satisfaction with the surgery. Radiological examination, post-operative complications, and reinterventions were recorded and analyzed.

Results

Very good results were obtained in all patients treated for aseptic loosening of the implant. However, inferior results were found in cases with infection. All patients operated on for aseptic loosening required only single-stage TKA, whereas patients with infection underwent multiple interventions. Complications were observed only in cases with infection.

Conclusions

Our study clearly outlined the differences in results based on failure mode, with far inferior results obtained in cases with infection. Given the lack of data in this area as well as the high specificity of this population, further high-quality studies are needed.

Salvage Procedures for Management of Prosthetic Joint Infection After Hip and Knee Replacements

Background:

The increasing load placed by joint replacement surgery on health care systems makes infection, even with the lowest rates, a serious concern that needs to be thoroughly studied and addressed using all possible measures.

Methods:

A comprehensive review of the current literature on salvage procedures for recurrent PJIs using PubMed, EMBASE and CINAHL has been conducted.

Results:

Prolonged suppressive antibiotic therapy (PSAT), resection arthroplasty and arthrodesis were the most common procedures performed. Suppressive antibiotic therapy is based on the use of well tolerated long term antibiotics in controlling sensitive organisms. Resection arthroplasty which should be reserved as a last resort provided more predictable outcomes in the hip whereas arthrodesis was associated with better outcomes in the knee. Various methods for arthrodesis including internal and external fixation have been described.

Conclusion:

Despite good union and infection control rates, all methods were associated with complications occasionally requiring further surgical interventions.

Predictors of hospital readmission following revision total knee arthroplasty

PURPOSE

Hospital readmission is emerging as an important quality measure, yet modifiable predictors of readmission remain unknown. This study was designed to identify risk factors for readmission following revision total knee arthroplasty.

METHODS

The National Surgical Quality Improvement Program dataset was queried to identify patients undergoing revision total knee arthroplasty from 2011 to 2012. Patient demographics, medical co-morbidities, laboratory values, surgical characteristics and surgical outcomes were examined using bivariate and multivariate logistic regression to identify significant predictors for readmission within 30 days of discharge.

RESULTS

There were 108 readmissions (6.2 %) among 1754 patients. Risk factors for readmission included a history of transient ischaemic attack/cerebrovascular accident (OR 3.47; 13 95 % CI 1.30, 9.25), female sex (OR 1.75, 95 % CI 1.15, 2.68) and general anaesthesia (OR 14 1.74, 95 % CI 1.09, 2.79). Hypertension treated with medication (OR 0.61, 95 % CI 0.39, 0.96) was associated with a lower risk of readmission. Post-operative complications that were significant predictors of hospital readmission included periprosthetic joint infection (OR 15.09, 95 % CI 5.57, 40.91), superficial wound infection (OR 16.57, 95 % CI 5.82, 47.22) and deep venous thrombosis (OR 8.59, 95 % CI 2.36, 31.24).

CONCLUSIONS

The preferred use of neuraxial anaesthesia and coordinated discharge planning in patients with a history of transient ischaemic attack/cerebrovascular accident may reduce the risk of readmission following discharge after revision total knee arthroplasty. Additionally, patients with post-operative infections and deep venous thrombosis following these procedures can benefit from close observation in the first weeks following discharge to minimize the likelihood of readmission.

LEVEL OF EVIDENCE

III.

Eradication rates, risk factors, and implant selection in two-stage revision knee arthroplasty: a mid-term follow-up study

Background

Two-stage revision (TSR) knee arthroplasty is an established treatment, but failure to control infection still occurs in 4–50 % of cases. The aim of this study was to assess the infection eradication rate, risk factors for failure, and the clinical outcome after two-stage revision knee arthroplasty.

Methods

This retrospective study included 59 patients who had undergone at least one two-stage revision procedure due to periprosthetic joint infection (PJI). Demographic data, comorbidities, types of implant, and complications were analyzed. Univariate and multivariate logistic regression analysis were used to identify risk factors for failure.

Results

The infections were controlled in 55 patients (93.2 %). The follow-up period was 4.1 (±2.7) years. Infection control was achieved after the first TSR in 42 patients (71.2 %) and after the second TSR in 13 (76.5 %). The percentage of arthrodesis procedures in patients with infection control increased from 16.75 % after one TSR to 69.2 % after two TSRs. Multivariate logistic regression analysis identified body mass index (BMI) (odds ratio 1.22; 95 % confidence intervals, 1.07 to 1.40; p = 0.004) and smoking (OR 21.52; 95 % CI, 2.60 to 178.19; p = 0.004) as risk factors for failure.

Conclusions

Two-stage revision protocols can achieve acceptable results even after a second procedure. It is still unclear whether the choice of implant influences failure rates. Risk factors for failure after two-stage revision were identified. Studies with larger sample sizes are needed in order to support these findings and identify further risk factors. To reduce failure rates, programs should be established to treat or minimize risk factors in patients with PJI.

Trends and Outcomes in the Treatment of Failed Septic Total Knee Arthroplasty: Comparing Arthrodesis and Above-Knee Amputation

BACKGROUND

Options for treatment of a failed septic total knee arthroplasty (TKA) include arthrodesis and above-knee amputation (AKA). Little comparative data exist to help clinicians when considering these alternatives.

METHODS

A national database was queried for patients who underwent either knee arthrodesis or AKA for an infected TKA between 2005 and 2012. Procedure volumes, postoperative complications, hospital charges, length of stay, and 90-day readmission rates were evaluated.

RESULTS

A total of 2634 patients underwent arthrodesis and 5001 patients underwent AKA for septic TKA. The percentage of total patients who underwent AKA increased significantly throughout the study period compared to knee arthrodesis. Patients who underwent AKA tended to be older and have more medical comorbidities. Arthrodesis patients had a significantly higher rate of postoperative infection (14.5% vs 8.3%, P < .0001) and transfusion (55.1% vs 46.8%, P < .0001), whereas AKA patients had a higher rate of systemic complications (31.5% vs 25.9%, P < .0001) and in-hospital mortality (3.7% vs 2.1%, P < .0001). The AKA cohort had lower hospital charges ($79,686 vs $84,747, P = .004), longer length of stay (11 vs 7 days, P < .0001), and higher 90-day readmission rate (19.4% vs 16.9%).

CONCLUSION

Our data suggest that there is an increasing trend toward AKA for the treatment of a failed infected TKA when compared to arthrodesis. Comparative analysis of the outcomes of these procedures should help the clinician when weighing these alternatives.

The management of an infected total knee arthroplasty

Periprosthetic joint infection (PJI) is one of the most feared and challenging complications following total knee arthroplasty. We provide a detailed description of our current understanding regarding the management of PJI of the knee, including diagnostic aids, pre-operative planning, surgical treatment, and outcome.

No improvement in the post-TKA infection prognosis when the implant is not reimplanted: Retrospective multicentre study of 72 cases

INTRODUCTION

For the surgeon and patient, permanent removal of an infected knee prosthesis is an unwelcome decision taken out of necessity because unfavourable local or general conditions may increase the likelihood of mechanical or infectious failure upon prosthesis reimplantation. The purpose of this study was to determine if permanent removal of an infected total knee arthroplasty (TKA) implant controls the infection and prevents above-the-knee amputation when reimplantation turns out to be too risky. It was hypothesized that removal without reimplantation contributes to eradicating the infection and helps to avoid amputation.

PATIENTS AND METHODS

Seventy-two consecutive patients who underwent TKA removal between 2000 and 2010 at 14 hospitals were reviewed. The TKA removal was followed by knee fusion in 29 cases or implantation of a permanent cement spacer in 43 cases.

RESULTS

If failure is defined as clinically obvious recurrence of the infection, the survival rate was 65 ± 5% at 2 years; 44% of patients had a recurrence of the infection, 8% had undergone amputation and 19% presented with nonunion at the last follow-up. The male gender and the presence of multiple co-morbidities were predisposing factors for failure.

DISCUSSION

Control of the infection is not guaranteed upon TKA implant removal; the success rate is lower than in cases of two-stage reimplantation. The outcomes in this study are worse than those of other published studies. This is likely due to the heterogeneity in the patient population and treatments, along with the presence of co-morbidities. This treatment option should be the last recourse before amputation.

Knee Fusion or Above-The-Knee Amputation after Failed Two-Stage Reimplantation Total Knee Arthroplasty

Prosthetic joint infection (PJI) is a serious complication of total knee arthroplasty (TKA). Control of infection after a failed two-stage TKA is not always possible, and the resolution of infection may require an above-knee amputation (AKA) or a the-knee (KF). The purpose of this review is to determine which treatment method (AKA or KF) yields better function and ambulatory status for patients after a failed two-stage reimplantation. A PubMed search related to the resolution of infection by means of an above-the-knee amputation (AKA) or a knee fusion was performed until 10 January 2015. The key words were: infected TKA and above-the-knee amputation. Five hundred and sixty-six papers were found, of which ten were reviewed because they were focused on the topic of the article. KF should be strongly considered as the treatment of choice for patients who have persistent infected TKA after a failed two-stage revision arthroplasty. Patients can walk at least inside the house, and activity of daily living independence is achieved by the patients with successful KF, although walking aids, including a shoe lift, are required. An intramedullary nail leads to better functional results than an external fixator. The functional outcome after AKA performed after TKA is poor. A substantial percentage of the patients never fit with a prosthesis, and those who are seldom obtain functional independence. Only 50% of patients are able to walk after AKA. Patients receiving KF for treating recurrent PJI after TKA have better function and ambulatory status compared to patients receiving AKA. KF must be recommended as the treatment of choice for patients who have persistent infected TKA after a failed two-stage reimplantation procedure.

Unsatisfactory outcome of arthrodesis performed after septic failure of revision total knee arthroplasty

BACKGROUND

Periprosthetic infection is one of the most dreaded orthopaedic complications. Current treatment procedures include one-stage or two-stage revision total knee arthroplasty. If the periprosthetic infection is no longer controllable after several revision total knee arthroplasties, many surgeons regard knee arthrodesis as a promising option. The aim of our study was to ascertain whether intramedullary nailing results in the suppression or eradication of an infection and to identify risk factors for persistent infection.

METHODS

All patients who had undergone intramedullary nailing following septic failure of revision total knee arthroplasty between 1997 and 2013 were included in the study. Pathogens, risk factors predisposing to persistent infection, and the rate of persistent infections were recorded. In addition, a visual analog scale (VAS) and Knee injury Osteoarthritis Outcome Score (KOOS), Knee Society Score (KSS), Lysholm, Short Form-36 (SF-36), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaires were completed to assess clinical outcomes and quality of life.

RESULTS

Twenty-six patients were included in the study. Thirteen (50%) had a persistent infection requiring additional revision surgery. Nineteen patients (73%) reported persistent pain (VAS score of >3). All scores showed marked impairment of quality of life.

CONCLUSIONS

Intramedullary nailing following septic failure of revision total knee arthroplasty must be regarded with skepticism, and we cannot recommend it. Repeat revision total knee arthroplasty or amputation should be considered as an alternative in such difficult cases.