Two-stage Revision Total Knee Arthroplasty Research Articles

No shortening of the patellar tendon during two-stage total knee arthroplasty revision using articulating spacers.

Surgical techniques in two-stage revision total knee arthroplasty(rTKA) include the use of articulating spacers and static spacers. Shortening of the patellar tendon could be a reason for inferior functional outcomes in two-stage septic rTKA. The aim of this study was to determine if articulating spacers also have negative effects on the extensor mechanism in rTKA. This retrospective study includes 65 consecutive patients (23 women, 42 men, age 71.3 ± 1.2; range, 51.2-88.6 years) undergoing septic two-stage rTKA using an articulating spacer between 2014 and 2021 in a single orthopedic center. For all patients, calibrated true lateral radiographs before total knee arthroplasty (TKA) explantation (T0), directly after TKA explantation (T1), shortly before TKA reimplantation (T2) and 6-8 days after TKA reimplantation (T3) were used to calculate the modified Insall Salvati ratio (mISR). Overall, the mISR decreased significantly immediately after explantation (T0 vs. T1, p = 0.002) from 1.43 ± 0.03 to 1.36 ± 0.03 and remained stable until T2 (1.37 ± 0.02, p = 0.74). Following TKA reimplantation, the mISR increased again to 1.43 ± 0.03 (T3). There were no significant differences between T0 and T3 (p = 0.88). Six out of 65 patients (9%) experienced patellar tendon shortening > 10% at T3. Septic two-stage revision TKA using an articulating spacer does not lead to patellar tendon shortening in the majority of cases. This study suggests that one reason for the improved range of motion after reimplantation may be the use of articulating spacers compared to static spacers.

Clinical outcomes of two-stage revision arthroplasty using a spiked tibial cement spacer in infected total knee arthroplasty.

A tibial cement spacer (TCS) with spikes offers better initial stability than a conventional TCS and reduces spacer-related problems in two-stage revision total knee arthroplasty (R-TKA) for infection. We compared the clinical outcomes of two-stage revision arthroplasty for infected TKA using spiked TCS with that of conventional TCS. This retrospective cohort study included 29 patients who underwent two-stage revision arthroplasty using an articulating cement spacer and who could be followed up for at least one year. Group S comprised 14 patients using spiked TCS, whereas Group C comprised 15 patients using conventional TCS. Demographic data, the interval from first to second stage revision, motion arc, numerical rating scale (NRS), Knee Society (KS) score, serum levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and frequency of repeating the first-stage and infection recurrence after R-TKA between the groups were analyzed. No significant differences were observed in the female ratio and mean age between both groups. The mean interval between the first and second stage revision was significantly shorter in Group S than in Group C. The mean motion arc was significantly larger in Group S than in Group C. The mean NRS was significantly lower in Group S than in Group C. The mean KS score in Group S was significantly higher than that in Group C. Serum ESR and CRP levels did not differ between the groups. The frequency of repeating the first stage was lower in Group S than in Group C. However, the recurrence rate after R-TKA was higher in Group S than in Group C. Compared with conventional TCS, spiked TCS shortened the period until R-TKA and improved pain and function levels. However, no significant difference existed in the rate of infection recurrence after R-TKA.

The Impact of Culture Negativity on the Outcomes of Revision Total Knee Arthroplasty for Chronic PJI.

Culture-positive (CP) and culture-negative (CN) periprosthetic joint infections (PJI) remain a crucial area of research; however, current studies comparing these infections rely on unstandardized outcome reporting tools. Our study aimed to compare the outcomes of two-stage revision of CP and CN PJI using the standardized Musculoskeletal Infection Society (MSIS) outcome reporting tool. We retrospectively reviewed 138 patients who were diagnosed with PJI and indicated for two-stage revision total knee arthroplasty (rTKA). The majority of patients in both CP and CN cohorts achieved infection control without the need for reoperation (54.1% and 62.5%, respectively). There was a significant difference in the overall distribution of MSIS outcomes (p = 0.043), with a significantly greater rate of CN patients falling into Tier 1 (infection control without the use of suppressive antibiotics) (52.5% versus 29.6%, p = 0.011). There was also a significant difference in the distribution of septic versus aseptic reoperations after 2nd stage (p = 0.013), with more CP reoperations being septic and more CN reoperations being aseptic. The duration from first to second stage was significantly shorter in the CN cohort (p = 0.002). While overall infection control was similar between cohorts, these data suggest that the outcomes of two-stage rTKA are favorable in cases of CN PJI.

Risk factors for early septic failure after two-stage exchange total knee arthroplasty for treatment of periprosthetic joint infection

BackgroundThe cause of early septic failure after two-stage exchange revision total knee arthroplasty (TKA) for chronic periprosthetic joint infection (PJI) and the factors affecting it are not well known. The purpose of this study was to determine the surgical outcomes and the risk factors for early septic failure after two-stage revision TKA for chronic PJI.MethodsWe identified a total of 246 adult patients who met the Musculoskeletal Infection Society (MSIS) diagnostic criteria for chronic PJI at two academic tertiary hospitals from March 2012 to December 2018. Finally, 151 patients who consecutively received two-stage exchange revision TKA for chronic PJI and who had a minimum 3-year follow-up were enrolled and retrospectively reviewed. Successful surgical treatment was evaluated for two-stage revision TKA and risk factors for early septic failure were identified.ResultsEarly septic failures occurred within 3 years after reimplantation in 48 patients (31.8%). After accounting for potentially confounding variables, we found that male patient [odds ratio (OR): 2.753, 95% confidence interval (CI) 1.099–6.893, p = 0.031], fungus or mycobacterial infection (OR: 5.224, 95% CI 1.481–18.433, p = 0.01), and positive culture at reimplantation (OR: 4.407, 95% CI 1.255–15.480, p = 0.021) were independently associated with early septic failure after two-stage exchange revision TKA.ConclusionMale patients, fungus or mycobacterial infection, and positive culture at reimplantation were independently associated with an increased risk of early septic failure after two-stage exchange revision TKA despite normal C-reactive protein values prior to reimplantation. Further prospective and high-quality studies are needed to determine the risk factors of two-stage exchange revision TKA for chronic PJI.Level of evidence: level IV; retrospective comparison; treatment study.

Outcome of Two-Stage Revision Total Hip and Knee Arthroplasty as a Salvage Procedure for Deep Infection of Peri-Articular Fracture Fixation: Propensity Score-Matched Study.

Failed open reduction internal fixation (ORIF) of peri-articular fractures due to deep infection is associated with decreased functional outcomes and increased mortality rates. Two-stage revision total joint arthroplasty (TJA) is often needed as a salvage procedure. The aim of this study was to evaluate the outcome of two-stage revision total hip and knee arthroplasty as a salvage procedure for the treatment of deep infection of peri-articular fracture fixation. Using propensity score-matching, a total of 120 patients was evaluated: 1) 40 consecutive patients were treated with planned salvage two-stage revision for the treatment of deep peri-articular infection, and 2) a control group of 80 patients who underwent two-stage revision for periprosthetic joint infection (PJI) after non-IF TJA. An infection occurred after a fracture of the acetabulum (27.5%), femoral neck (22.5%), intertrochanteric femur (15.0%), subtrochanteric femur (5.0%), femoral shaft (7.5%), distal femur (5.0%), and tibia (15.0%). At an average follow up of 4.5 years (range, 1.0-25.8), the overall failure rate was 42.5% for the IF group compared to 21.3% for the non-ORIF group (P=0.03). There was a significantly higher reinfection rate for the IF group compared to the non-IF group (35.0% vs. 11.3%, p=0.005). Tissue cultures for the IF patients demonstrated significantly higher polymicrobial growth (30.0% vs. 11.3%, P=0.01) and methicillin-resistant Staphylococcus aureus (20.0% vs. 7.5%, P=0.04). Salvage two-stage revision arthroplasty for infected IF of peri-articular fractures was associated with poor outcome. The overall post-operative complications after salvage two-stage revision for infected IF of peri-articular fractures was high with 35% reinfection rates associated with the presence of mixed and resistant pathogens.

A comparsion study between debridement, antibiotics, and implant retention and two-stage revision total knee arthroplasty for the management of periprosthetic joint infection occurring within 12 weeks from index total knee arthroplasty

BackgroundManaging periprosthetic joint infections are variable in practices. Debridement, antibiotics, and implant retention (DAIR) is one of the favorable interventions. Given that the success rate of the two-stage revision total knee arthroplasty (rTKA) might be overestimated. The purpose of this study is to compare the success rate between DAIR and standard two-stage rTKA with a comparable intervention time.MethodsWe retrospectively reviewed the consecutive knee periprosthetic joint infection cases which underwent DAIR or two-stage rTKA (all procedures were performed by the senior author) within 12 weeks since their primary TKA between July 2009 and October 2019. Average follow-up was 72.20 ± 40.70 months (range 29–148 months) in the DAIR group compared to 89.14 ± 43.06 months after spacer insertion (range 29–163 months) in the two-stage revision group (P = 0.156). According to different interventions, demographic data; timing of surgical intervention; hospital for special surgery knee score; and success rate were collected and compared between the DAIR group and two-stage revision group. Failure of treatment was based on the Delphi consensus and the fate of spacers. The pathogen types and failure cases were also recorded and analyzed.ResultsAverage follow-up was 72.20 ± 40.70 months (range 29–148 months) in the DAIR group compared to 89.14 ± 43.06 months after spacer insertion (range 29–163 months) in the two-stage revision group. Time from index surgery was 3.90 ± 2.92 weeks (range 0–12 weeks) in the DAIR group, and 5.11 ± 2.86 weeks (range 0–12 weeks) in the 2-stage exchange group, respectively. The success rate was 70.0% and 75.0% in the DAIR group and two-stage revision group, respectively. But no significant differences were observed between the two groups.ConclusionDAIR demonstrated comparable effectiveness with two-stage rTKA. We recommended DAIR as a choice for patients with current infection within 12 weeks after primary TKA. For methicillin-resistant staphylococcal infections and fungal infections, two-stage rTKA might be preferred.

Does spiked tibial cement spacer reduce spacer-related problems in two-stage revision total knee arthroplasty for infection?

PurposeArticulating cement spacers are frequently used in staged approaches for infected total knee arthroplasty (TKA). This study investigated whether a tibial cement spacer (TCS) with spikes could reduce spacer-related problems in two-stage revision TKA (R-TKA).MethodsA total of 27 patients (27 knees; 10 men and 17 women) who underwent two-stage R-TKA for infected TKA were retrospectively analyzed. Group A comprised 12 patients who used TCS with spikes added to the bottom surface, whereas group B consisted of 15 patients who used conventional TCS with a flat bottom. For each group, plain radiographs were obtained after cement spacer implantation and before R-TKA to measure mediolateral (ML) translation and TCS’s tilting angle. Patients’ demographic data, ML translation of the TCS, and changes in the TCS’s tilting angle between the groups were analyzed.ResultsThe mean ML translation was significantly lower in group A than that in group B (1.7 mm vs. 5.4 mm, p = 0.04). The mean change in the tilting angle was significantly lower in group A than that in group B (4.5° vs. 19.4°, p = 0.047).ConclusionThe spiked TCS in two-stage R-TKA provides superior stability compared to the TCS with a conventional design.

The Fate and Relevance of the Patella in Two-Stage Revision Total Knee Arthroplasty for Periprosthetic Joint Infection

BackgroundIt remains unclear whether reimplantation of a patellar component during a two-stage revision for periprosthetic total knee arthroplasty infection (PJI) affects patient reported outcome measures (PROMs) or implant survivorship. The purpose of this study was to evaluate whether patellar resurfacing during reimplantation confers a functional benefit or increases implant survivorship after two-stage treatment for PJI. MethodsTwo-stage revisions for knee PJI performed by three surgeons at a single tertiary care center were reviewed retrospectively. All original patellar components and cement were removed during resection and the patella was resurfaced whenever feasible during reimplantation. PROMs, implant survivorship, and radiographic measurements (patellar tilt and displacement) were compared between knees reimplanted with a patellar component versus those without a patellar component. ResultsA total of 103 patients met the inclusion criteria. Forty-three patients (41.7%) underwent reimplantation with, and 60 patients (58.3%) without a patellar component. At a mean follow-up of 33.5 months, there were no significant differences in patient demographics or PROMs between groups (P ≥ .156). No significant differences were found in the estimated Kaplan-Meier all-cause, aseptic, or septic survivorship between groups (P ≥ .342) at a maximum of 75 months follow-up. There was no significant difference in the change (pre-resection to post-reimplant) of patellar tilt (P = .504) or displacement (P = .097) between the groups. ConclusionPatellar resurfacing during knee reimplantation does not appear to meaningfully impact postoperative PROMs or survivorship. Given the risk of potential extensor mechanism complications with patellar resurfacing, surgeons may choose to leave the patella without an implant during total knee reimplantation and expect similar clinical outcomes. Level of EvidenceLevel III.

Static vs Articulating Spacers for Two-Stage Revision Total Knee Arthroplasty: Minimum Five-Year Review.

BackgroundThe gold standard treatment for infected total knee arthroplasty (TKA) is two-stage revision. The first stage involves a temporary antibiotic spacer, which can be static or articulating; it remains unclear which is best. We aimed to compare 5-year outcomes between static and dynamic spacers.MethodsOne hundred and seventy-six patients with infected TKA requiring two-stage revision were enrolled. Patients were organized based on the type of spacer used during the first-stage revision. One hundred and four patients received articulating spacers, and 72 received static spacers. At 5 years, postoperative range of motion (ROM), Short Form 12 (SF-12), Knee Society Score (KSS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were recorded. Reinfection and revisions were also tracked.ResultsEradication of infection was similar in both groups, with 83.7% in the articulating group and 86.1% in the nonarticulating spacer group (P = .234). Articulating spacers resulted in significantly improved ROM (111 vs 82 degrees, P < .001), SF-12 physical component score (35.2 vs 31.0, P = .01), KSS (145.2 vs 113.7, P < .001), and WOMAC function scores (60.1 vs 51.1, P = .03) as compared to the static spacer group.ConclusionsTreatment with an articulating spacer as opposed to a static spacer resulted in improved ROM, SF-12 physical component score, KSS, and WOMAC function scores at the final follow-up visit. There was no significant difference in reinfection rates. Patients requiring staged revision for infected TKA may benefit from an articulating spacer.

Depression Is Transiently Increased in Patients Undergoing Two-Stage Revision Arthroplasty.

BackgroundThe implications of two-stage revision on mental health are poorly understood. The purpose of this study is to determine (1) whether patients undergoing two-stage revision total hip and knee arthroplasty for prosthetic joint infection were more likely to get Patient-Reported Outcomes Measurement Information System (PROMIS) Depression scores consistent with major depressive disorder (MDD) than those undergoing aseptic revision and (2) whether these symptoms resolved after the procedure.MethodsRecords of all 366 patients that underwent revision total hip or knee arthroplasty from January 1, 2015, – June 20, 2019, were reviewed. Forty-two patients were excluded for missing PROMIS Depression scores or incomplete treatment. Preoperative (<3 months), early postoperative (2-8 weeks), and final postoperative (6-18 months) Depression scores were collected. Patients crossing the PROMIS Depression threshold equivalent to a Patient Health Questionnaire-9 score ≥10, indicative of MDD, were evaluated.ResultsMore two-stage revision patients developed Depression scores indicative of MDD perioperatively than the aseptic cohort (20.0% vs 6.5%, P = .01). Two-stage revision patients had higher (worse) median Depression scores preoperatively (54.8 vs 51.3, P = .04) and at early follow-up (54.3 vs 49.9, P = .01), but not at final follow-up (50.4 vs 49.1, P = .39). Across all patients, Depression scores improved by 2.4 points at early follow-up (95% confidence interval:1.1–3.7; P < .001) and 3 points at final follow-up (95% confidence interval:1.5-4.5; P < .001; minimal clinically important difference 3.0).ConclusionsTwenty percent of two-stage revision arthroplasty patients, compared to <7% of aseptic revision patients, developed PROMIS Depression scores consistent with MDD during treatment. At final follow-up, a clinically significant improvement in Depression scores from baseline was evident in both cohorts.

Repeat two‐stage revision for knee prosthetic joint infection results in very high failure rates

Two stage revision total knee arthroplasty (TKA) is the gold standard for treatment and eradication of knee prosthetic joint infections (PJI), but the literature is limited on the outcomes of repeat two-stage TKA after PJI recurrence. This study presents the outcomes of repeat two-stage revision TKA and investigates potential factors contributing to success or failure, aiming to assist counselling and decision-making. A retrospective study was undertaken investigating all two-stage revision TKA performed at one institution between 2005 and 2020. Twenty cases underwent repeat two-stage revision TKA. Patient outcomes and factors contributing to treatment success or failure were investigated. PJI was diagnosed according to MSIS criteria. Of the 20 cases, 14 were classified as failed treatment (70%) due to a failure to eradicate infection, further surgical intervention or death. In this cohort, there were no statistically significant differences between the groups regarding factors contributing to treatment success or failure. In the success group, patient reported functional outcomes were variable. This study demonstrates that patients undergoing a repeat two-stage TKA have very poor outcomes. This study did not identify any factors that predicted failure. Patients need to be counselled regarding poor outcomes with repeat two-stage TKA, and other treatment options such as early amputation or lifelong suppression should be considered.

Detailed Revision Risk Analysis after Single- vs. Two-Stage Revision Total Knee Arthroplasty in Periprosthetic Joint Infection: A Retrospective Tertiary Center Analysis.

Periprosthetic joint infection (PJI) remains one of the most common causes of revision knee arthroplasty. Controversy continues to surround the proper operative technique of PJI in knee arthroplasty with single- or two-stage replacement. Significant variations are seen in the eradication rates of PJI and in implant survival rates. This detailed retrospective analysis of a single tertiary center is intended to provide further data and insight comparing single- and two-stage revision surgery. A retrospective analysis of all revision total knee arthroplasty (TKA) surgeries from 2013 to 2019 was performed and screened with respect to single- or two-stage TKA revisions. Single- and two-stage revisions were analyzed with regard to implant survival, revision rate, microbiological spectrum, and other typical demographic characteristics. A total of 63 patients were included, with 15 patients undergoing single-stage revision and 48 patients undergoing two-stage revision. The mean follow-up time was 40.7 to 43.7 months. Statistically, no difference was found between both groups in overall survival (54.4% vs. 70.1%, p = 0.68) and implant survival with respect to reinfection (71.4% vs. 82.4%, p = 0.48). Further, high reinfection rates were found for patients with difficult-to-treat organisms and low- to semi-constrained implant types, in comparison to constrained implant types. A statistically comparable revision rate for recurrence of infection could be shown for both groups, although a tendency to higher reinfection rate for single-stage change was evident. The revision rate in this single-center study was comparably high, which could be caused by the high comorbidity and high proportion of difficult-to-treat bacteria in patients at a tertiary center. In this patient population, the expectation of implant survival should be critically discussed with patients.

Clinical outcomes of two-stage revision total knee arthroplasty in infected cases with antibiotic-loaded cement spacers produced using a handmade silicone mold

PurposeThis study assessed the clinical outcomes of periprosthetic joint infection patients who underwent two-stage revision total knee arthroplasty with antibiotic-loaded cement spacers fabricated using a handmade silicone mold.Materials and methodsThis study included seven patients (average age 77 years, average follow-up time 54 months) who underwent surgery at our hospital between 2009 and 2013. Clinical outcomes including knee scores, function scores, knee range of motion, and walking ability at the final observation, period from the primary total knee arthroplasty to implant removal, period from implant removal to revision total knee arthroplasty, and follow-up period after revision total knee arthroplasty were investigated.ResultsAt the final follow-up, the average knee range of motion was 99°, with no significant differences at each stage; average knee and function scores were 84 and 77, respectively. With cement spacers, five patients were able to walk with a t-cane. No recurrence of infection was observed.ConclusionsThe clinical outcomes of the current case series demonstrated good knee function with preserved walking ability, without any recurrence of periprosthetic joint infection. This study suggests that using a handmade silicone mold could be an effective option for periprosthetic joint infection after a total knee arthroplasty.

Elevated ESR and CRP Prior to Second-Stage Reimplantation Knee Revision Surgery for Periprosthetic Joint Infection Are Associated with Increased Reinfection Rates.

Although two-stage revision surgery is considered as the most effective treatment for managing chronic periprosthetic joint infection (PJI), there is no current consensus on the predictors of optimal timing to second-stage reimplantation. This study aimed to compare clinical outcomes between patients with elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) prior to second-stage reimplantation and those with normalized ESR and CRP prior to second-stage reimplantation. We retrospectively reviewed 198 patients treated with two-stage revision total knee arthroplasty for chronic PJI. Cohorts included patients with: (1) normal level of serum ESR and CRP (n = 96) and (2) elevated level of serum ESR and CRP prior to second-stage reimplantation (n = 102). Outcomes including reinfection rates and readmission rates were compared between both cohorts. At a mean follow-up of 4.4 years (2.8-6.5 years), the elevated ESR and CRP cohort demonstrated significantly higher reinfection rates compared with patients with normalized ESR and CRP prior to second-stage reimplantation (33.3% vs. 14.5%, p < 0.01). Patients with both elevated ESR and CRP demonstrated significantly higher reinfection rates, when compared with patients with elevated ESR and normalized CRP (33.3% vs. 27.6%, p = 0.02) as well as normalized ESR and elevated CRP (33.3% vs. 26.3%, p < 0.01). This study demonstrates that elevated serum ESR and/or CRP levels prior to reimplantation in two-stage knee revision surgery for chronic PJI are associated with increased reinfection rate after surgery. Elevation of both ESR and CRP were associated with a higher risk of reinfection compared with elevation of either ESR or CRP, suggesting the potential benefits of normalizing ESR and CRP prior to reimplantation in treatment of chronic PJI.

Globulin, the albumin-to-globulin ratio, and fibrinogen perform well in the diagnosis of Periprosthetic joint infection

BackgroundAlthough periprosthetic joint infection (PJI) is a severe complication of total joint arthroplasty (TJA), the diagnosis of PJI remains challenging. Albumin (ALB), globulin (GLB), the albumin-to-globulin ratio (AGR), and fibrinogen could be indicators of the body’s inflammatory state. This study aimed to compare the diagnostic accuracy of these biomarkers with that of other inflammatory biomarkers in PJI patients.MethodsWe conducted a retrospective cohort study that included a consecutive series of patients undergoing debridement antibiotic irrigation and implant retention (DAIR), one-stage or the first stage of a two-stage revision total knee arthroplasty (TKA) or total hip arthroplasty (THA) for acute (n = 31) or chronic (n = 51) PJI, or revision TKA or THA for aseptic failures (n = 139) between January 2017 and December 2019 in our hospital. The 2013 criteria of the Musculoskeletal Infection Society (2013 MSIS) were used as the reference standard for the diagnosis of PJI. The preoperative ALB, GLB, AGR, fibrinogen, D-dimer, platelet count, fibrin degradation product (FDP), platelet-to-lymphocyte (PLR), platelet count to mean platelet volume ratio (PVR), neutrophil-to-lymphocyte ratio (NLR), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were assessed. The receiver operating characteristic curve (ROC), sensitivity, and specificity were utilized to compare different biomarkers.ResultsCompared with the aseptic patients, the GLB, D-dimer, fibrinogen, FDP, platelet count, PVR, PLR, NLR, ESR, and CRP levels of PJI patients were significantly higher (P < 0.01); however, the ALB and AGR levels were significantly lower (P < 0.01). The area under the curve (AUC), sensitivity and specificity were 0.774, 67.50, 77.54% for ALB; 0.820, 57.50, 89.86% for GLB; 0.845, 66.25, 93.48% for AGR; 0.832, 78.48, 78.95% for fibrinogen; 0.877, 81.48, 85.07% for ESR; 0.909, 83.95, 88.89% for CRP; 0.683, 55.22, 75.83% for D-dimer; 0.664, 38.81, 88.33% for FDP; 0.678, 52.44, 79.86% for platelet count; 0.707, 48.78, 86.33% for PVR; 0.700, 51.22, 80.58% for PLR; and 0.678, 52.44, 81.30% for NLR, respectively. In the clinic, GLB, AGR and fibrinogen could be used for diagnosis of patients suspected of having PJI.ConclusionOur study demonstrated that GLB, AGR, and fibrinogen were promising biomarkers in the diagnosis of PJI.

The Inverse Spacer—A Novel, Safe, and Cost-Effective Approach in Routine Procedures for Revision Knee Arthroplasty

Background: A major disadvantage of current spacers for two-stage revision total knee arthroplasty (R-TKA) is the risk of (sub-) luxation during mobilization in the prosthesis-free interval, limiting their clinical success with detrimental consequences for the patient. The present study introduces a novel inverse spacer, which prevents major complications, such as spacer (sub-) luxations and/or fractures of spacer or bone. Methods: The hand-made inverse spacer consisted of convex tibial and concave femoral components of polymethylmethacrylate bone cement and was intra-operatively molded under maximum longitudinal tension in 5° flexion and 5° valgus position. Both components were equipped with a stem for rotational stability. This spacer was implanted during an R-TKA in 110 knees with diagnosed or suspected periprosthetic infection. Postoperative therapy included a straight leg brace and physiotherapist-guided, crutch-supported mobilization with full sole contact. X-rays were taken before and after prosthesis removal and re-implantation. Results: None of the patients experienced (sub-) luxations/fractures of the spacer, periprosthetic fractures, or soft tissue compromise requiring reoperation. All patients were successfully re-implanted after a prosthesis-free interval of 8 weeks, except for three patients requiring an early exchange of the spacer due to persisting infection. In these cases, the prosthetic-free interval was prolonged for one week. Conclusion: The inverse spacer in conjunction with our routine procedure is a safe and cost-effective alternative to other articulating or static spacers, and allows crutch-supported sole contact mobilization without major post-operative complications. Maximum longitudinal intra-operative tension in 5° flexion and 5° valgus position appears crucial for the success of surgery.

Long-term result of a second or third two-stage revision total knee arthroplasty for infected total knee arthroplasty

BackgroundPersistent or recurrent infection after two-stage revision total knee arthroplasty (TKA) for the treatment of an infected TKA is a dreaded complication. The purpose of the current study was to determine the ability of a second or third two-stage revision TKA to control infection, evaluate the long-term survivorship of the TKA prosthesis, and measure the functional outcome after a second or third two-stage revision TKA for reinfection.MethodsWe evaluated 63 patients (65 knees) with failed two-stage TKA treated with a second or a third two-stage revision TKA. There were 25 men and 38 women (mean age, 67 ± 10.2 years). The mean follow-up from the time of a second two-stage TKA revision was 15.1 years (range, 10 to 19 years) and the mean follow-up from the time of a third two-stage TKA revision was 7 years (range, 5 to 10 years).ResultsOverall, infection was successfully controlled in 49 (78%) of 65 knees after a second two-stage revision TKA was performed. In the remaining 16 knees, recurrent infection was successfully controlled in 12 knees (75%) after a third two-stage revision TKA. Survivorship, free of implant removal for recurrent infection, was 94% at 15.1 years (95% CI, 91 to 100%). Survival free of revision TKA for mechanical failure was 95% (95% CI, 92 to 100%).ConclusionsThe results of the current study suggest that a second or a third two-stage revision TKA is a reasonable option for controlling infection, relieving pain, and achieving a satisfactory level of function for patients with infected TKAs.

Mid-Term Results of Two-stage Revision Total Knee Arthroplasty for Infected Total Knee Arthroplasty

Introduction. Today, knee arthroplasty is one of the most common surgical procedures. Infection after endoprosthetics is the most dangerous complication in patients who have undergone total knee arthroplasty, which negatively affects the prognosis. Most cases of infection develop within the first 2 years after surgery, and the frequency is 1.5%, and after that it decreases to 0.5%. Material and Method. When a study group of 31 patients (22 female, 9 male) who were diagnosed with infected knee prosthesis and underwent two-stage revision knee prosthesis as a treatment method; the mean age of all patients (31 patients) was 68.78 years. In our study by using the American knee association scoring system; preoperative knee scores of 31 patients who underwent two-stage revision surgery were 35.43 ± 7.14, while this parameter was found to be 83.27 ± 8.89 postoperatively (p &lt;0.01). Conclusion. We believe that two-stage revision surgery is an effective method in the treatment of infection that develops after primary total knee arthroplasty application. Restoration of the joint line in accordance with the anatomical structure will positively affect the clinical results, and the use of a long stem to increase the stability of the prosthesis is appropriate for successful results, especially in the cases with bone defects. Key words: Total Knee Arthroplasty, Two-Stage Revision Surgery, Infected Knee Prosthesis.

How I do it — Second stage revision total knee arthroplasty

BackgroundInfection is a potentially devastating complication following primary total knee arthroplasty, and the traditional gold-standard treatment for chronic prosthetic joint infection has been in the form of a two-stage revision total knee arthroplasty. This involves a first stage – removal of all implants and infected material, with implantation of a temporary spacer – followed by a second stage which includes reimplantation with a definitive prosthesis. IndicationsAlthough the outcomes of single-stage and two-stage revision arthroplasty surgeries are similar, there are certain indications such as atypical or more virulent organisms, patient factors and soft tissue factors that would favour a two-stage approach. Surgical techniqueThe second stage revision procedure consists of explantation of the spacer with a debridement and synovectomy. Further samples are sent for microbiological analysis. Once the surgical field is clean and lavaged, the definitive prosthesis is implanted. ConclusionsA second stage revision total knee arthroplasty is a reliable procedure for the treatment of chronic prosthetic joint infection. There is a significant re-revision rate, predominantly due to recurrent deep infection.

The Effect of Time Spent with a Dynamic Spacer on Clinical and Functional Outcomes in Two-Stage Revision Knee Arthroplasty.

The present study aimed to evaluate the effect of a longer interval between the first and second stages of infected total knee arthroplasty (TKA) revision on the clinical and functional outcome. This study included a total of 56 patients who underwent two-stage revision TKA with a dynamic spacer with a minimum of 2years of follow-up. Patients were categorized into two groups according to time with the spacer: < 3months (Group 1, 31 patients) or > 3months (Group 2, 25 patients). Clinical outcome and quality of life were assessed by knee range of motion (ROM), Knee Society Score for Knee (KSS-K), Knee Society Score for Function (KSS-F) and Short Form 36 (SF-36). The mean follow-up period was 48 ± 19.1months (range, 24-84months). The KSS-K, KSS-F, and ROM values were significantly higher in Group 1 than in Group 2 (p < 0.05). The SF-36 scores for general health, physical function, and bodily pain were significantly higher in Group 1 (p < 0.05). Re-infection occurred in 10 patients (17.8%). Time with spacer was not associated with re-infection development (Group 1, n = 6, 19% vs. Group 2, n = 4, 16%; p > 0.05). Increased duration with a spacer is associated with poorer clinical and functional outcomes as well as higher treatment costs in two-stage revision knee arthroplasty. Surgeons can attempt to reduce the time patients spend in a spacer to obtain better postoperative functional outcomes, as well as a better quality of life. 3.