Mid-term results of tibial cones

Aims Tibial cones are often utilized in revision total knee arthroplasty (TKA) with metaphyseal defects. Because there are few studies evaluating mid-term outcomes with a sufficient cohort, the purpose of this study was to evaluate tibial cone survival and complications in revision TKAs with tibial cones at minimum follow-up of five years. Methods A retrospective review was completed from September 2006 to March 2015, evaluating 67 revision TKAs (64 patients) that received one specific porous tibial cone during revision TKA. The final cohort was composed of 62 knees (59 patients) with five years of clinical follow-up or reoperation. The mean clinical follow-up of the TKAs with minimum five-year clinical follow-up was 7.6 years (5.0 to 13.3). Survivorship analysis was performed with the endpoints of tibial cone revision for aseptic loosening, tibial cone revision for any reason, and reoperation. We also evaluated periprosthetic joint infection (PJI), risk factors for failure, and performed a radiological review. Results The rate of cone revision for aseptic loosening was 6.5%, with an eight-year survival of 95%. Significant bone loss (Anderson Orthopaedic Research Institute grade 3) was associated with cone revision for aseptic loosening (p = 0.002). The rate of cone revision for any reason was 17.7%, with an eight-year survival of 84%. Sixteen percent of knees developed PJI following revision. A pre-revision diagnosis of reimplantation as part of a two-stage exchange protocol for infection was associated with both PJI (p < 0.001) and tibial cone revision (p = 0.001). Conclusion Mid-term results of tibial cones showed a survivorship free of cone revision for aseptic loosening of 95%. Patients with significant bone loss were more likely to have re-revision for tibial cone failure. Infection was common, and patients receiving cones at reimplantation were more likely to develop PJI and undergo cone revision. Cite this article: Bone Joint J 2021;103-B(6 Supple A):158–164.

Modified hybrid cementing technique reduces stem tip pain and improves patient’s satisfaction after revision total knee arthroplasty

Background There have been no studies comparing patient-reported outcome measures including end-of-stem tip pain and patient satisfaction based on the use of cementing techniques in revision total knee arthroplasty (TKA). The purpose of this study was to compare end-of-stem tip pain and PROMs with hybrid and modified hybrid cementing techniques in revision TKAs. Method Sixty-two cases of revision TKA performed by a single surgeon were divided into two groups based on the cementing technique with a minimum follow-up of 2 years. Two types of cementing technique for femoral and tibial stems were used as follows: (1) a hybrid cementing technique (33 cases), in which cement was applied immediately distal to the modular junction of the stem and the component while the distal stem was press-fitted into the diaphysis without using cement; and (2) a modified hybrid cementing technique (29 cases), in which cement was applied to the tip of femoral and tibial stems. The thigh and shin were assessed for the end-of-stem tip pain. Patient satisfaction was evaluated based on the satisfaction items of New Knee Society Score. Results Modified hybrid cementing significantly lowered the percentage of patients manifesting shin pain (3.4% vs. 24.2%, p = 0.029). Patients treated with the modified hybrid cementing technique showed a higher satisfaction rate (p = 0.003). Multivariate logistic regression analysis showed an increase in the odds of satisfaction 32.686-fold (p = 0.004) in patients without pain at the end-of-stem tip in the shin and 9.261-fold (p = 0.027) in patients treated with the modified hybrid cementing technique. Conclusion The modified hybrid cementing technique for fixation of long-stem in revision TKAs reduced the end-of-stem tip pain in the shin, leading to significantly higher satisfaction compared with the hybrid cementing technique after revision TKA. Level of evidence Level III

Association of Anesthesia Type with Postoperative Outcome and Complications in Patients Undergoing Revision Total Knee Arthroplasty

Revision total knee arthroplasty (TKA) is an increasingly common procedure and is effective in treating knee osteoarthritis, but it has higher complication rates than primary TKA. Anesthetic choice poses perioperative risk that has been extensively studied in primary TKA, showing favorable results for regional anesthesia compared with general anesthesia. The impact of anesthetic choice in revision TKAs is not well studied. A retrospective cohort study was conducted using the American College of Surgeons National Surgical Quality Improvement Program database. Patients who underwent revision TKAs between 2014 and 2017 were divided into three anesthesia cohorts: (1) general anesthesia, (2) regional anesthesia, and (3) combined general-regional anesthesia. Univariate and multivariate analyses were used to analyze patient characteristics and 30-day postoperative outcomes. Bonferroni correction was applied for post hoc analysis. In total, 8,820 patients were identified. Of whom, 3,192 patients underwent general anesthesia, 3,474 patients underwent regional anesthesia, and 2,154 patients underwent combined anesthesia. After multivariate analyses, regional anesthesia was associated with decreased odds for any complication (p = 0.008), perioperative blood transfusion (p < 0.001), and extended length of stay (p < 0.001) compared with general anesthesia. In addition, regional anesthesia was associated with decreased odds for perioperative blood transfusion (p < 0.001) and extended length of stay (p = 0.006) compared with combined anesthesia. However, following multivariate analysis, regional anesthesia was not associated with decreased odds of wound, pulmonary, renal, urinary tract, thromboembolic, and cardiac complications, and was not associated with return to operating room, extended length of stay, minor and major complications, and mortality. Retrospective analysis of a large surgical database suggests that patients receiving general anesthesia have increased likelihood for developing adverse postoperative outcomes relative to patients receiving regional anesthesia. Prospective and controlled trials should be conducted to verify these findings.

Outcomes of a technique combining diaphyseal impaction grafting and metaphyseal cones for severe bone loss in revision total knee arthroplasty

Aims Metaphyseal cones with cemented stems are frequently used in revision total knee arthroplasty (TKA). However, if the diaphysis has been previously violated, the resultant sclerotic canal can impair cemented stem fixation, which is vital for bone ingrowth into the cone, and long-term fixation. We report the outcomes of our solution to this problem, in which impaction grafting and a cemented stem in the diaphysis is combined with an uncemented metaphyseal cone, for revision TKA in patients with severely compromised bone. Methods A metaphyseal cone was combined with diaphyseal impaction grafting and cemented stems for 35 revision TKAs. There were two patients with follow-up of less than two years who were excluded, leaving 33 procedures in 32 patients in the study. The mean age of the patients at the time of revision TKA was 67 years (32 to 87); 20 (60%) were male. Patients had undergone a mean of four (1 to 13) previous knee arthroplasty procedures. The indications for revision were aseptic loosening (80%) and two-stage reimplantation for prosthetic joint infection (PJI; 20%). The mean follow-up was four years (2 to 11). Results Survival free from revision of the cone/impaction grafting construct due to aseptic loosening was 100% at five years. Survival free from any revision of the construct and free from any reoperation were 92% and 73% at five years, respectively. A total of six patients (six TKAs, 17%) required a further revision, four for infection or wound issues, and two for periprosthetic fracture. Radiologically, one unrevised TKA had evidence of loosening which was asymptomatic. In all unrevised TKAs the impacted diaphyseal bone graft appeared to be incorporated radiologically. Conclusion When presented with a sclerotic diaphysis and substantial metaphyseal bone loss, this technique combining diaphyseal impaction grafting with a metaphyseal cone provided near universal success in relation to implant fixation. Moreover, radiographs revealed incorporation of the bone graft and biological fixation of the cone. While long-term follow-up will be important, this technique provides an excellent option for the management of complex revision TKAs. Cite this article: Bone Joint J 2020;102-B(6 Supple A):116–122.

Varus-valgus constraint in 416 revision total knee arthroplasties with cemented stems provides a reliable reconstruction with a low subsequent revision rate at early to mid-term review

Aims Varus-valgus constrained (VVC) implants are often used during revision total knee arthroplasty (TKA) to gain coronal plane stability. However, the increased mechanical torque applied to the bone-cement interface theoretically increases the risk of aseptic loosening. We assessed mid-term survivorship, complications, and clinical outcomes of a fixed-bearing VVC device in revision TKAs. Methods A total of 416 consecutive revision TKAs (398 patients) were performed at our institution using a single fixed-bearing VVC TKA from 2007 to 2015. Mean age was 64 years (33 to 88) with 50% male (199). Index revision TKA diagnoses were: instability (n = 122, 29%), aseptic loosening (n = 105, 25%), and prosthetic joint infection (PJI) (n = 97, 23%). All devices were cemented on the epiphyseal surfaces. Femoral stems were used in 97% (n = 402) of cases, tibial stems in 95% (n = 394) of cases; all were cemented. In total, 93% (n = 389) of cases required a stemmed femoral and tibial component. Femoral cones were used in 29%, and tibial cones in 40%. Survivorship was assessed via competing risk analysis; clinical outcomes were determined using Knee Society Scores (KSSs) and range of movement (ROM). Mean follow-up was four years (2 to 10). Results The five-year cumulative incidence of subsequent revision for aseptic loosening and instability were 2% (95% confidence interval (CI) 0.2 to 3, number at risk = 154) and 4% (95% CI 2 to 6, number at risk = 153), respectively. The five-year cumulative incidence of any subsequent revision was 14% (95% CI 10 to 18, number at risk = 150). Reasons for subsequent revision included PJI (n = 23, of whom 12 had previous PJI), instability (n = 13), and aseptic loosening (n = 11). The use of this implant without stems was found to be a significant risk factor for subsequent revision (hazard ratio (HR) 7.58 (95% CI 3.98 to 16.03); p = 0.007). KSS improved from 46 preoperatively to 81 at latest follow-up (p < 0.001). ROM improved from 96° prerevision to 108° at latest follow-up (p = 0.016). Conclusion The cumulative incidence of subsequent revision for aseptic loosening and instability was very low at five years with this fixed-bearing VVC implant in revision TKAs. Routine use of cemented and stemmed components with targeted use of metaphyseal cones likely contributed to this low rate of aseptic loosening. Cite this article: Bone Joint J 2020;102-B(4):458–462.

Aseptic Loosening of Porous Metaphyseal Sleeves and Tantalum Cones in Revision Total Knee Arthroplasty: A Systematic Review

Bone loss often complicates revision total knee arthroplasty (TKA). Management of metaphyseal defects varies, with no clearly superior technique. Two commonly utilized options for metaphyseal defect management include porous-coated metaphyseal sleeves and tantalum cones. A systematic review was conducted according to the international Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We combined search terms “Total knee arthroplasty” AND/OR “Sleeve,” “Cone” as either keywords or medical subject heading (MeSH) terms in multiple databases according to PRISMA recommendations. All retrieved articles were reviewed and assessed using defined inclusion and exclusion criteria. A total of 27 studies (12 sleeves and 15 cones) of revision TKAs were included. In the 12 studies on sleeve implantation in revision TKAs, 1,617 sleeves were implanted in 1,133 revision TKAs in 1,025 patients. The overall rate of reoperation was 110/1,133 (9.7%) and the total rate of aseptic loosening per sleeve was 13/1,617 (0.8%). In the 15 studies on tantalum cone implantation in revision TKAs, 701 cones were implanted into 620 revision TKAs in 612 patients. The overall rate of reoperation was 116/620 (18.7%), and the overall rate of aseptic loosening per cone was 12/701 (1.7%). Rates of aseptic loosening of the two implants were found to be similar, while the rate of reoperation was nearly double in revision TKAs utilizing tantalum cones. Variability in the selected studies and the likely multifactorial nature of failure do not allow for any definitive conclusions to be made. This review elucidates the necessity for additional literature examining revision TKA implants.

Validation of Lithuanian Arthroplasty Register Telephone Survey of 2769 Patients Operated for Total Knee Replacement

Background and objectives: The aim of our study is to validate the registration of knee arthroplasty revisions in the Lithuanian Arthroplasty Register (LAR) and thus give an indication of the accuracy of the published revision rates. Materials and methods: A total of 4269 primary total knee arthroplasties (TKAs) registered in the LAR between 2013 and 2015 were included. Two years after surgery the patients were contacted by phone in order to inquire if they had been subject to revision. The information from the patients was then cross checked against what had been registered in the LAR, and in case of a revision not having been registered hospital charts were investigated. Thus, the patients were followed up with regarding revision and/or death until 2017. A true revision was defined as an addition, exchange, or removal of one or all components. Results: Out of 4269 primary TKAs, we managed to contact and interview 2769 patients. Nine small hospitals were not able to provide contact details (telephone numbers) for 533 patients (549 knees). Sixty-seven patients (67 knees) were deceased (data from the Lithuanian National Census Register) and a further 438 patients (565 knees) appeared to have a wrong or non-valid telephone number, leaving 3031 (3091 knees) patients being contacted. Of those, 262 patients (266 knees) refused to participate in the study which left 2769 responders (2825 knees). Sixty-one patients said that reoperation had been performed on the index knee within two years of their primary surgery. After checking with the clinics, 10 were surgical procedures on the knee but not true revisions by our criteria. Out of the 51 true revisions we found that 46 were registered to the LAR as revised, while five (9.8%) revisions were missing. Conclusions: We conclude that the Lithuanian Arthroplasty Register has a good completeness of registered revision TKAs as only 9.8% of revisions were missing.

Are Joint Surgeons Being Adequately Compensated for Single-Component versus Double-Component Revision TKA? An Analysis of Relative Value Units

Relative value units (RVUs) are used for ensuring that physicians are appropriately reimbursed based on case complexity. While past research has elucidated that surgeons are reimbursed at a higher rate for primary total knee arthroplasty (TKA) versus revision TKA, no study has explored differences in reimbursements between single-component and double-component revisions, considering a double-component revision is likely to require more effort/skill as compared with single-component revision. The 2015 to 2016 American College of Surgeons National Surgical Quality Improvement Program files were queried using Current Procedural Terminology (CPT) codes for single-component revision TKA (CPT-27486) and double-component revision TKA (CPT-27487). A total of 1,962 single-component and 4,184 double component revisions were performed during this period. Total RVUs, RVU/min, and dollar amount/min were calculated for each case. The mean RVU was 21.12 and 27.11 for single-component and double-component revision TKAs, respectively. A statistically significant difference was noted in mean operative time (single component = 100.44 vs. double component = 144.29; p < 0.001) between the two groups. Single-component revision had a significantly higher mean RVU/min (0.267) versus double-component revision (0.223). The reimbursement amounts calculated for single-component versus double-component revisions were per minute ($9.58/min vs. $8.00/min), per case ($962.22 vs. $1,154.32), and per day ($5,773.32 vs. $4,617.28) with a projected annualized cost difference of $184,966. Orthopaedic surgeons are reimbursed at a higher rate for single-component revision TKAs as compared with double-component revision TKAs, despite the higher complexity and longer operative times required in the latter. The study highlights the need for a change in the RVUs for either double-component or single-component revision to ensure reimbursement per unit time is adequate for performing a complex case such as double-component revision TKA.

The Impact of Gender on Postoperative Complications after Revision Total Knee Arthroplasty

Knee osteoarthritis is a common form of arthritis, often treated by total knee arthroplasty (TKA). Complications can arise after TKAs, which may necessitate revision TKAs and further treatments. However, there remains a paucity of literature regarding influence of gender on postoperative complication rates after revision TKA. A retrospective cohort study was conducted using the American College of Surgeons National Surgical Quality Improvement Program database. Patients who received revision TKAs between 2007 and 2014 were identified and recorded as male or female. Univariate and multivariate analysis was used to evaluate the incidence of multiple adverse events within 30 days of revision TKA. This study included 9,914 patients who underwent revision TKA (females = 5,728 [57.8%]; males = 4 186 [42.2%]). Male patients were shown to be at greater risk for developing 7 of 17 complications compared with female patients, and female patients were shown to be at greater risk for urinary tract infection (UTI) development. Multivariate analysis showed males as an independent risk factor for four complications and females as an independent risk factor for UTI development. Male patients were more likely to develop more complications postoperatively than female patients. Although the possibility of developing complications is relatively low, orthopaedic surgeons should be aware of increased postoperative complication rates when counseling patients who undergo revision TKA.

Blood Loss in Primary and Aseptic Revision Total Knee Arthroplasty: A Retrospective Matched Cohort Analysis

Background and Hypothesis: While blood loss in primary TKA is well-characterized, there is a paucity of data on blood loss in aseptic revision TKA. In this study, we hypothesized that revision TKAs would have increased blood loss compared to matched primary TKAs. Project Methods: Two-hundred-ninety consecutive revision TKAs performed between 2010 and 2017 were retrospectively reviewed and matched to primary TKAs on surgeon, age, sex, BMI, and ASA Score. Seventy-four revision TKAs were excluded for factors affecting blood loss. Potential covariates affecting blood loss were compiled from the medical record. Outcomes including total blood loss, drain output rate, and change in hemoglobin levels from preoperative to postoperative day one were assessed. Results: Two-hundred-sixteen revision TKAs matched to 216 primary TKAs were analyzed. Multivariate analysis showed no difference in blood loss metrics comparing primary and revision TKAs. However, increased tourniquet time (p=0.001), elevated BMI (p=0.002), male sex (p<0.001), and lack of topical TXA (p=0.005) significantly increased total blood loss. Similar results were found for increased drain output rate in addition to lack of intravenous TXA (p<0.001) and a trend for lower age (p=0.073). Increased tourniquet time (p=0.004) and lack of topical TXA (p=0.002) correlated with a greater drop in hemoglobin postoperatively. Conclusion and Potential Impact: Primary and revision TKAs showed no difference in blood loss. However, increased tourniquet time and withholding topical TXA significantly increased total blood loss, drain output rate, and change in hemoglobin levels. This data continues to support emphasizing procedural efficiency and TXA use in revision TKA.