Mortality Following Revision Total Knee Arthroplasty: A Matched Cohort Study of Septic versus Aseptic Revisions

We report the medium-term mortality after septic versus aseptic revision total knee arthroplasty (TKA) and factors that can contribute to mortality in revision TKA. Mortality rates of 88 patients undergoing septic revision (septic group) were compared with age- and year of surgery-matched 88 patients of aseptic revision (aseptic group). The overall mortality after revision TKA was 10.7% at a median of 4 years of follow-up (range, 2–7 years). However, the mortality after septic revision (18%, 16/88) was six times higher than that of aseptic revision (3%, 3/88) (P = 0.003). Infections with Staphylococcus aureus and/or methicillin resistance was not associated with higher mortality rates. Multivariate analysis indicated that increased age (P < 0.001), higher ASA class (P = 0.002), and septic revision (P < 0.001) were identified as independent predictors of increased mortality after revision TKA.     

Use of Stepped Porous Titanium Metaphyseal Sleeves for Tibial Defects in Revision Total Knee Arthroplasty: Short Term Results

Stepped porous titanium metaphyseal sleeves may provide an option for enhanced fixation in managing challenging tibial defects in revision total knee arthroplasty (TKA). We retrospectively reviewed data on 51 patients who underwent revision TKA utilizing a metaphyseal sleeve for Anderson Orthopaedic Research Institute (AORI) Type II and III tibial defects between June 2007 and July 2011. Of these 51 patients, 36 patients had complete clinical and radiographic data. At final follow-up (mean: 38 months) significant improvements in knee range of motion and Knee Society scores were observed postoperatively (P < 0.001). Four revision procedures were necessary, but none for aseptic implant fixation failure. Radiographic review at final follow-up revealed stable, osteointegrated components without component migration or clinically significant osteolysis. Metaphyseal sleeve use in the management of moderate to severe tibial defects in revision TKA resulted in satisfactory clinical outcomes and is a versatile option for achieving stable fixation.     

14-Year Median Follow-Up Using the Press-Fit Condylar Sigma Design for Total Knee Arthroplasty

Median 14-year follow-up (mean 11.8 years) of a cemented primary posterior cruciate-retaining total knee arthroplasty (TKA) utilizing the Press-Fit Condylar (PFC) Sigma design was evaluated in 77 patients (79 TKA). Follow-up assessment included implant survivorship, x-rays, Knee Society rating system, and clinical evaluation. Radiographic analysis demonstrated minor non-progressive osteolysis in 40% (10/25) knees. Two revisions, one for instability at 4 years and one for polyethylene wear at 10 years were performed. Survivorship of the PFC Sigma knee implant was 97% using revision for any reason and 100% using aseptic loosening as endpoints. The PFC Sigma had excellent survivorship at 14 years, the longest clinical follow-up reported.     

Hybrid fixation versus full-cemented or full-cementless fixation in total knee arthroplasty: Systematic review and meta-analysis of comparative studies

ObjectiveHybrid fixation is one alternative to full-cemented fixation in total knee arthroplasty (TKA) with theoretical advantages. Hybrid fixation may offer the advantages of cementless femoral fixation, while also avoiding the problem of tibial loosening in full-cementless TKA. The purpose of the study is to determine whether hybrid TKA may perform comparably to or better than full-cemented and full-cementless TKA.MethodsWe searched the MEDLINE, EMBASE and Cochrane Library databases through September 2018 for randomized controlled trials and observational studies comparing outcomes of hybrid versus full-cemented or full-cementless fixation techniques. Outcomes of interest included aseptic loosening, overall reoperation rate, infection, radiolucent lines and operating time. Data were pooled with the Mantel–Haenszel random effects model.ResultsWe included 14 studies with follow-up ranging from 2.7 to 9.6 years in our quantitative analysis, of which 7 studies compared hybrid fixation with full-cemented TKA and another 7 compared hybrid fixation with full-cementless TKA. Combined data revealed that the hybrid fixation group had a similar rate of aseptic loosening compared with cemented (P = 0.19) and cementless (P = 0.49) groups. There was no difference with respect to other outcomes, including overall reoperation rate, infection, radiolucent lines and operating time between groups.ConclusionHybrid, cementless and cemented TKAs have comparable mid-term results as it pertains to aseptic loosening, overall reoperation, infection, radiolucent lines and operating time. Further comparative studies are needed to investigate these potential effects over the long-term.     

Tumor Endoprosthesis Revision Rates Increase With Peri-Operative Chemotherapy But Are Reduced With the Use of Cemented Implant Fixation

Chemotherapy may reduce osseointegration of tumor endoprosthesis, while delaying chemotherapy may reduce survival. We studied the effects of chemotherapy and cemented fixation on tumor endoprosthesis survivorship with a retrospective analysis of 50 consecutive patients receiving lower limb salvage surgery. We compared rates of radiographic loosening/revision and effect of cement fixation between chemotherapy/no chemotherapy cohorts. Chemotherapy increased the total revision rate (HR = 3.8 [1–14], P = 0.033), but did not affect aseptic loosening. Cement fixation reduced revision for loosening (HR = 0.09 (0.008–0.98),P = 0.012) and showed less radiographic loosening (HR = 0.09 (0.02–0.51),P = 0.00066). Cement fixation had lower rates of revision for loosening and radiographic loosening regardless of whether chemotherapy was given. We conclude that for these implants, cement fixation provides superior results to uncemented fixation.     

Initial Implant Stability Predicts Migration But Not Failure in Cementless Acetabular Revision with Bone Grafting

Host bone contact of less than 50% is perceived but not proven to cause migration and loosening after actetabular revision. A prospective analysis of cementless acetabular revision cases with impaction grafting was performed to determine if this was an independent risk factor for these events. Sixty-two hips in 54 patients were assessed at a mean follow-up of 84.5 months (range 61–112) yielding a probability of 94.6% of retaining the acetabular component using revision for aseptic loosening as the end point. No single factor was independently causative for loosening, although Type III fixation was associated with migration (p = 0.0159); subanalysis suggested that achieving host–bone contact in at least part of the dome and posterior column is important.     

High Incidence of Tibial Component Loosening After Total Knee Arthroplasty Using Ceramic Titanium-Nitride-Coated Mobile Bearing Prosthesis in Moderate to Severe Varus Deformity: A Matched-Pair Study Between Ceramic-Coated Mobile Bearing and Fixed Bearing Prostheses

BackgroundWe compared the incidence of aseptic component loosening and subsequent revision, and the survival rate between ceramic titanium-nitride-coated mobile bearing (MB) and fixed bearing total knee arthroplasties (TKAs) performed in patients with moderate to severe varus deformities.MethodsIn total, 200 TKAs using advanced coated system posterior stabilized prostheses in varus deformity of mechanical axis >8° between 2012 and 2016 were retrospectively reviewed. One hundred MB (ceramic-m group) and 100 fixed bearing (ceramic-f group) prostheses were included. The matches were made according to preoperative demographics, range of motion, and severity of deformity. The mean follow-up period was not different (ceramic-m vs ceramic-f = 4.8 vs 5.1 years; P = .104). The incidence of revision TKA due to aseptic component loosening and the survival rate (failure: revision due to aseptic loosening) was investigated.ResultsThe incidence of revision TKA due to aseptic component loosening was 7 (7%) in the ceramic-m group and 1 (1%) in the ceramic-f group (P = .032). All cases of aseptic loosening occurred at the tibial component. The overall survival rate was 91.3% in the ceramic-m group and 98.9% in the ceramic-f group (P = .025).ConclusionConsidering the higher revision incidence and lower survival rate due to tibial component loosening, caution should be taken in tibial component fixation when using advanced coated system MB prosthesis in moderate to severe varus deformity.Level of EvidenceIII     

Tantalum Cones for Severe Bone Defects in Revision Knee Arthroplasty: A Minimum 10-Year Follow-Up

BackgroundTwo-to 6-year results of reconstruction of severe bone defects in revision total knee arthroplasty (TKA) with highly porous tantalum cones have been encouraging, but 10-year follow-up is lacking. The purpose of this study was to determine the minimum 10-year results of tantalum cones in revision TKA.MethodsFrom 2005 to 2010, 30 consecutive patients (30 knees) underwent revision TKA with the use of cones. All patients were followed clinically and radiographically for a minimum of 10 years. A total of 42 cones (25 tibial and 17 femoral) were used to reconstruct massive bone defects classified as Anderson Orthopaedic Research Institute Types 2A (10), 2B (12), and 3 (19). The mean age of the patients was 73 years (range, 55 to 84) at the time of revision. The indication for the revision included aseptic loosening (15 patients) and second-stage reimplantation for deep infection (15 patients). Six patients were lost to follow-up.ResultsIn total, 6 cones had to be revised. Minimum 10-year cone survivorship for any reason was 81% (25 of 31 cones). With cone revision for aseptic loosening as the end point, survivorship was 96% (30 of 31). No evidence of loosening or migration of any implant was noted on the most recent radiographs.ConclusionMetaphyseal fixation with tantalum cones in revision TKA demonstrated excellent survivorship and fixation at a minimum follow-up of 10 years. This type of metaphyseal reconstruction can be a durable option for revision TKA in patients who have massive bone defects.     

Total Knee Arthroplasty After Lower Extremity Amputation: A Review of 13 Cases

Below knee amputation protects the ipsilateral knee from osteoarthritis and overloads the contralateral knee predisposing it to symptomatic osteoarthritis. We retrospectively reviewed 13 primary total knee arthroplasty (TKAs) in 12 patients with a prior lower extremity amputation. Twelve TKAs were performed on the contralateral side of the amputated limb while only one TKA was performed on the ipsilateral side. The average clinical follow-up was 6.8 ± 4.8 years. Knee Society Scores improved from 30.4 ± 11.8 to 88.5 ± 4.2 after TKA with a prior contralateral amputation. Three (23.1%) patients with TKA after contralateral amputation had aseptic loosening of the tibial component. Patients experience clinically significant improvement with TKA after lower extremity amputation. Augmentation of tibial fixation with a stem may be advisable during TKA after contralateral amputation.     

Superior Survival of Fully Cemented Fixation Compared to Hybrid Fixation in a Single Design Rotating Hinge Knee Implant

BackgroundClinical observations revealed higher rates of aseptic loosening for hybrid fixated rotating hinge knee implants compared to fully cemented ones. We hypothesize that the use of a fully cemented fixation technique had a higher survival rate for aseptic loosening compared to a hybrid fixation technique in a rotating hinge knee implant.MethodsAll procedures of patients who were treated with the RT-PLUS rotating hinge knee implant (Smith & Nephew, Memphis, TN) between 2010 and 2018 were included. Primary outcome was revision for aseptic loosening. Kaplan-Meier survivorship and Cox proportional hazard regression analysis were performed to calculate survival rates and hazard ratios.ResultsA total of 275 hinge knee implants were placed in 269 patients (60 primary procedures, 215 revisions). Median follow-up was 7.3 ± 3.9 years. In total, 24 components (16 hybrid femur, 2 fully cemented femur, 6 hybrid tibia; all revision procedures) in 19 patients were revised for aseptic loosening. Kaplan-Meier survivorship analysis showed superior survival rates of fully cemented components (femur 97.1%; tibia 100%) compared to hybrid fixated components (femur 89.5%; tibia 95.9%) at the 10-year follow-up. Multivariate Cox hazard analysis showed a significantly higher risk of aseptic loosening for hybrid fixated components, a prior stemmed component and the femoral component.ConclusionFully cemented fixation showed superior survival rates for aseptic loosening compared to hybrid fixation in a single design rotating hinge knee implant. A prior stemmed component appears to be a risk factor for aseptic loosening and the femoral component seems to be more prone to loosening.     

Cemented long-stem revision total knee arthroplasty

From 1981 to 1989, 38 cemented, posterior, stabilized, revision, total knee arthroplasties (TKAs) were performed at the authors' institution using the stemmed kinematic stabilizer prosthesis of a single design. The mean clinical follow-up after the index procedure was 10.1 years. The Knee Society pain score averaged 17 points before revision and improved to 51 points at last follow-up, and the function score averaged 48 points before revision and improved to 57 at last follow-up. Ten-year component survival free of revision or removal for any reason was 96.7%; 11-year component survival free of revision for aseptic loosening was 95.7%. Cemented stem fixation in revision TKA provides good clinical results with durable fixation at an average of 10 years' follow-up.     

Survivorship of Metaphyseal Sleeves in Revision Total Knee Arthroplasty

Background

Metaphyseal fixation has promising early results in providing component stability and fixation in revision total knee arthroplasty (TKA). However, there are limited studies on midterm results of metaphyseal sleeves. We analyzed complications, rerevisions, and survivorship free of revision for aseptic loosening of metaphyseal sleeves in revision TKA.

Contemporary Total Hip and Total Knee Arthroplasty Results in Patients with Hemochromatosis

BackgroundHemochromatosis can result in metabolic bone pathology (due to excessive iron absorption) and degenerative joint disease, leading to total joint arthroplasties. The aim of this study is to analyze the survivorship, complications, radiographic results, and clinical outcomes of patients with hemochromatosis who received either a total hip arthroplasty (THA) or a total knee arthroplasty (TKA).MethodsWe identified 34 lower extremity arthroplasties in 29 patients with hemochromatosis performed between 2000 and 2016. There were 17 primary THAs in 15 patients and 17 primary TKAs in 14 patients. Mean age at arthroplasty was 63 years with 76% being male. The mean body mass index was 28 kg/m². Mean follow-up was 5 years.ResultsThe survivorship free from any revision for THAs was 94% at 10 years. One patient was revised for aseptic loosening of the femoral stem at 6 months. In THA patients, no infections, no other complications, and no radiographic evidence of aseptic loosening were identified. Harris Hip Scores improved from a mean of 55 preoperatively to 94 postoperatively (P < .001). The survivorship free from any revision for TKAs was 100% at 10 years. Two patients (12%) developed acquired idiopathic stiffness postoperatively; no infections were identified. There was no radiographic evidence of aseptic loosening in any TKA. Knee Society Scores improved from a mean of 61 preoperatively to 94 postoperatively (P < .001).ConclusionThis study found excellent survivorship, significant improvements in clinical outcomes, and a very low complication profile for both THA and TKA in patients with hemochromatosis.     

Weight Gain After Primary Total Knee Arthroplasty Is Associated With Accelerated Time to Revision for Aseptic Loosening

BackgroundObesity is a major health problem worldwide and is associated with complications after total knee arthroplasty (TKA). It remains unknown whether a change in body mass index (BMI) after primary TKA affects the reasons for revision TKA or the time to revision TKA.MethodsA total of 160 primary TKAs referred to an academic tertiary center for revision TKA were retrospectively stratified according to change in BMI from the time of their primary TKA to revision TKA. The association between change in BMI and time to revision was also analyzed according to indication for revision of TKA using Pearson's chi-square test.ResultsThe mean change in BMI from primary to revision TKA was 0.82 ± 3.5 kg/m². Maintaining a stable weight after primary TKA was protective against late revision TKA for any reason (P = .004). Patients who failed to reduce their BMI were revised for aseptic loosening earlier, at less than 5 years (P = .020), whereas those who reduced their BMI were revised later, at over 10 years (P = .004).ConclusionMaintaining weight after primary TKA is protective against later revision TKA for any reason but failure to reduce weight after primary TKA is a risk factor for early revision TKA for aseptic loosening and osteolysis. Orthopedic surgeons should recommend against weight gain after primary TKA to reduce the risk of an earlier revision TKA in the event that a revision TKA is indicated.     

Cementless vs Cemented Tibial Fixation in Primary Total Knee Arthroplasty

Background

The ideal fixation for modern tibial components in total knee arthroplasty (TKA) remains controversial with uncertainty on whether cementless implants can yield equivalent outcomes to cemented fixation in early follow-up.

Total Knee Arthroplasty With Fully Porous-Coated Stems For The Treatment of Large Bone Defects

Between February1999 and April 2006, 25 patients (28 knees) underwent a TKA by a single surgeon. At an average final follow-up of 7 ± 2 years (range, 3–10 years), 34 (100%) of 34 fully porous stems had achieved bone ingrowth. However, one case (3%) had a component loosening due to the de-bonding of sheets of beads from the stem. The remaining cases remained well fixed. Three well-fixed stems in 2 patients failed from deep infection. There was one reoperation required for a femoral periprosthetic fracture. Our 10-year experience shows that fully porous-coated stems reliably achieve durable fixation in complex primary and revision TKA allowing the surgeon to bypass large bone defects and gain fixation in diaphyseal bone.     

Cemented vs Uncemented Femoral Components: A Randomized,Controlled Trial at 10 Years Minimum Follow-Up

BackgroundThe type of total knee arthroplasty (TKA) fixation (cemented or uncemented) is still subject to debate. The aim of this study is to assess the survival rate, clinical outcomes, and radiological results of TKA according to the fixation type.MethodsA total of 130 patients were randomly assigned to either the cement group (cemented femoral and tibial implants) or the hybrid group (cemented tibial implant, uncemented femoral implant). The inclusion criteria were patients between 50 and 90 years old who underwent primary TKA for osteoarthritis between 2004 and 2005 without a history of open knee surgery. Revisions and complications were reported, as well as clinical scores and radiological signs of loosening.ResultsOne hundred eighteen patients had complete data at 10 years of minimum follow-up (59 in each group). The mean age was 72 years old. The mean follow-up was 13 years. The survival rate was 98% at 13 years in both groups (1 aseptic loosening at 2 years in the cement group, 1 septic loosening in the hybrid group). The complication rate in the cement group was 8.5% (n = 5) vs 12.1% (n = 7) in the hybrid group (P = .8). The clinical results were not significantly different. In the cement group, 25% of patients (n = 15) had radiolucent lines at 10 years. In the hybrid group, 33% of patients had bone transparencies, not evolving or symptomatic.ConclusionAt a minimum follow-up of 10 years, there were no significant differences between cemented TKA and hybrid TKA for the survivorship, the complication rate, the clinical scores, or the radiological signs of loosening.Level of EvidenceI.     

Patient-Reported Outcomes and Satisfaction 1 to 3 Years After Revisions of Total Knee Arthroplasties for Unexplained Pain Versus Aseptic Loosening

BackgroundIt is unknown if patients are relieved of pain after knee arthroplasty revision for unexplained pain. The aim of this cross-sectional case-control study was to compare patient-reported outcome measures (PROMs) and satisfaction 1 to 3 years after revision of total knee arthroplasties (TKAs) for the indications of unexplained pain versus aseptic loosening.MethodsWe included 384 patients undergoing TKA revision for the indications of unexplained pain and aseptic loosening from January 1, 2018 to December 31, 2020 from the Danish Knee Arthroplasty Register. A total of 81 patients were revised for unexplained pain and 303 for aseptic loosening. Questionnaires including PROMs (Oxford Knee Score, EQ-5D-5L, and Forgotten Joint Score) and satisfaction with the surgery on a 0-100 scale (100 = not satisfied; 0 = very satisfied) were sent to digitally secured mailboxes. Time from revision to data collection was a median 3.1 years (range, 1.4-4.4 years).ResultsMedian Oxford Knee Score was 25 (interquartile range [IQR] 15) versus 31 (IQR 18) 1-3 years after revisions for unexplained pain versus aseptic loosening, P = .009. Median EQ-5D-5L was 0.6 (IQR 0.4) versus 0.8 (IQR 0.3) for unexplained pain versus aseptic loosening, P = .009. Median Forgotten Joint Score was 50 (IQR 7) versus 50 (IQR 16) for unexplained pain versus aseptic loosening, P = .905. Satisfaction was 75 (IQR 38) for unexplained pain and 50 (IQR 73) for aseptic loosening, P < .001.ConclusionPatients undergoing TKA revision for the indication of unexplained pain had worse results on PROMs than those revised for aseptic loosening. Likewise, patients revised for unexplained pain were less satisfied compared to patients revised for aseptic loosening. This information is valuable to both surgeons and patients when candidates for revision surgery are selected, to obtain the best possible outcomes.     

Varus-Valgus Constrained Implants With a Mobile-Bearing Articulation: Results of 367 Revision Total Knee Arthroplasties

BackgroundVarus-valgus constrained (VVC) implants are used for compromised ligamentous stability in revision total knee arthroplasties (TKAs). Mobile-bearing VVC implants may reduce rotational forces; yet, limited clinical data exist. The purpose of this study is to report mid-term risk of re-revision, complications, and clinical outcomes with a mobile-bearing VVC implant.MethodsThree hundred thirty-seven patients (367 TKAs) who underwent revision TKA with a mobile-bearing VVC implant between 1999 and 2013 at a single institution were reviewed. Mean age at revision was 67 years. Mean follow-up was 4 years. The main indications for revision were aseptic loosening in 158 cases (43%), reimplantation after 2-stage exchange arthroplasty in 120 (33%), instability in 61 (17%), and other in 28 (7%). Clinical outcomes were assessed by Knee Society Scores, and survivorship was analyzed with death as the competing risk.ResultsThe 5-year cumulative incidences of any re-revision or re-revision for aseptic loosening were 9% and 3%, respectively. Twenty-six knees (7%) were re-revised: 15 for infection, 6 for aseptic loosening, and 5 for other causes. There were 17 cases of irrigation and debridement, 10 cases of manipulations under anesthesia, and 9 cases of periprosthetic fractures. There were no bearing “spin-outs.” The mean Knee Society Scores improved from 45 preoperatively to 77 at most recent follow-up (P < .001).ConclusionThe functional improvement and 5-year cumulative incidence of revision of a mobile-bearing VVC implant demonstrated acceptable outcomes with no unique complications related to the mobile-bearing construct. Additional follow-up will be needed to determine long-term implant survivorship.     

Minimum 20-Year Follow-Up Results of Revision Total Hip Arthroplasty With Improved Cementing Technique

A consecutive, non-selective cohort of 83 (77 patients) cemented total hip arthroplasty revisions using contemporary cementing techniques was analyzed at a minimum of 20 years following the index procedure. No patients were lost to follow-up. The average age at revision was 62.4 years (23 to 89). Twenty-two hips (26.5%) had had a reoperation, eighteen (21.7%) for aseptic loosening, 3 (3.6%) for femoral prosthesis fracture and 1 (1.2%) for dislocation. The incidence of re-revision for aseptic femoral loosening was 7.5% and for aseptic acetabular loosening was 21.7%. These results confirm that cemented femoral revision using improved cementing techniques is a durable option in revision hip surgery. In contrast to this, THA revisions using a cemented acetabular component have been less durable at this length of follow-up.