Survival Of Total Knee Arthroplasty Research Articles

The effect of anatomical tibia vara on the coronal alignment of tibial component in total knee arthroplasty: A radiographic analysis

Survivorship in total knee arthroplasty depends on the restoration of the coronal alignment of its components. Failure to restore this may decrease the longevity of TKR. The prevalence of tibia vara in patients with osteoarthritis of the knee undergoing TKA is quite high. We wanted to assess the effect of the varus angulation in the proximal metaphysis of the tibia on tibial component malposition in the coronal plane in patients undergoing total knee replacement. Patients who underwent TKA for primary osteoarthritis of the knee and with more than two years of follow-up were included. The extra-articular tibial deformity was assessed by measuring the angle between the anatomical and mechanical axis of the tibia. The coronal alignment of the femoral and tibial components was measured using lateral distal femoral angle and medial proximal tibial angle.Preoperatively,73 (90.12%) patients were having a neutral tibial anatomical axis and 8(9.9%) patients were having varus angulation in the proximal tibia.Postoperatively,18(22.2%) patients had a neutral mechanical axis. There were 14(17.2%) patients with more than 3 degrees of varus mechanical axis and 41(50.6%) patients had less than 3 degrees of varus mechanical axis alignment. 2 (2.5%) patients had more than 3-degree valgus mechanical axis and 6 (7.4%) had less than 3 degrees valgus mechanical axis. Postoperatively, out of 8 patients with pre-operative tibia vara, only 2(25%) patients had neutral placement of the tibial component. 6 (75%) had both tibial and femoral component malalignment. Out of the 73 patients with pre-operatively neutral tibial axis, 40(54.7%) patients had both tibial and femoral component malalignment. 8 (11%) patients had only tibial and 9(12.3%) patients had only femoral component malalignment. In 16 (19.1%) patients, there was no malalignment of both. There was no significant relationship between the tibial anatomical axis malalignment and the tibial component alignment in patients undergoing TKA for primary osteoarthritis.

Long-term survivorship of total knee arthroplasty with a single-radius, high-flexion posterior stabilized prosthesis

BackgroundThe purpose of this study was to determine functional outcomes, implant survival rate, and complications of a single-radius, high-flexion posterior stabilized (PS) total knee prosthesis at a minimum follow up of 10 years for a consecutive series. MethodsThis retrospective observational study included 395 consecutive patients who underwent 585 single-radius, PS total knee arthroplasties (TKAs) between January 2009 and December 2009. Their functional outcomes, implant survival rates, radiological findings, and complications were evaluated. ResultsAt a mean follow up of 11.2 years (range, 10.6–11.8 years), 395 (80.8%) patients were available for review. At final follow up, preoperative Knee Society knee scores were improved from 37.3 to 80.1 (P < 0.05) and function scores were improved from 35.7 to 80.5 points (P < 0.05). Sixteen knees (2.7%) in 15 patients required revision surgery due to 11 septic loosening (1.9%) and five aseptic loosening events (0.8%). Cumulative survival for the prosthesis was 97.3% for any cause at 10 years. A total of 34 radiolucent lines (5.8%) were detected an average of 2.4 years following surgery and radiological assessment did not reveal any evidence of component migration at final follow up. ConclusionsSingle-radius, high-flexion PS TKA showed good long-term survival rates and clinical outcomes. Further study is required to determine whether limited radiolucency findings at the tibial component–tibial plateau could progress to or result in the loosening of components.

Mid-to Long-Term Survival of Total Knee Arthroplasty in Hemophilic Arthropathy.

While satisfactory results have been reported during short-to mid-term follow-up assessments of hemophilic patients who have undergone total knee arthroplasty (TKA), limited literature focusing on long-term survival following TKA exists to date. As part of this investigation, a consecutive series of 78 TKAs in 56 patients with hemophilic arthropathy was reviewed. The mean patient age at the time of operation was 38.7 years old and the mean length of follow up was 10.2 years. Clinical and radiologic outcomes, quality of life, complications, and long-term survivorship of TKA were evaluated. At the latest point of follow up, the average American Knee Society (AKS) knee and function scores had improved from 32.1 to 85.7 points and 41.5 to 83.3 points, respectively. Moreover, the average range of motion (ROM) was significantly increased from 64.2° preoperatively to 84.2° postoperatively. The physical and mental Short Form-36 results were also significantly improved at the latest point of follow up. Postoperative complications appeared in 12 knees (15.4%). The readmission rate in the 30 days after discharge was 6.4%. Revision TKA was performed in three knees for periprosthetic joint infection (n = 2 knees) and tibial component loosening (n = 1 knee). The Kaplan–Meier 10- and 13-year prosthesis survival rates were 97.1% and 93.2%, respectively. The current study suggests that the mid-to long-term results of TKA in patients with hemophilic arthropathy are favorable, with successful long-term prosthesis survival achievable in most cases.

Tibial crest alignment technique-an effective technique to improve coronal alignment of tibial component in tka for arthritic knees

Introduction:Long term survivorship in Total Knee Arthroplasty is significantly dependent on prosthesis alignment.Accuracy of component positioning relies on alignment guides for making precise and accurate bone cuts.Hypotheses:The aim of this study was to determine, compare and analyse the coronal alignment of the tibial component of a single implant system using 3 different techniques.Methods:Retrospective study of cases from a prospectively collected database. Radiological assessment included measurement of the coronal alignment of tibial components of total knee arthroplasties, and its deviation from the mechanical axis. A comparison study of intramedullary, extramedullary and tibial crest alignment methods was performed.Results:66 consecutive patients (3 groups of 22 each). Mean BMI was 26. The mean angle of deviation from the mechanical axis was significantly lesser (p< 0.05) in the Tibial crest alignment group patients compared to the other 2 groups. Moreover, the number of outliers (+/-3 degrees) were 2 and 4 in the intra and extramedullary group, whereas there were none in the tibial crest group. The inter and intraclass correlation coefficient was 0.8 and 0.9 respectively.Conclusion:The Tibial Crest Alignment Technique is an effective technique to produce consistent results to achieve optimal coronal alignment of the tibial component in TKA, even in patients with high BMI.

The Association of Calcium and Vitamin D Use With Implant Survival of Total Knee Arthroplasty: A Nationwide Population-Based Cohort Study

BackgroundCalcium and vitamin D have been regarded as beneficial nutrients for bone metabolism that may affect survival of arthroplasties. However, the relationship between their use and revision rate of knee arthroplasty has not been evaluated. Thus, we investigated an association between calcium and vitamin D use and the revision rate after primary total knee arthroplasty. MethodsA nationwide population-based cohort study was conducted using the Korean National Health Insurance database. We included patients diagnosed with knee osteoarthritis and underwent primary total knee arthroplasty between 2009 and 2018. Risk for arthroplasty revision was estimated using a Cox proportional hazards model with time-dependent covariates. Log-rank test was used to assess survival of knee arthroplasty. ResultsOut of 142,147 subjects, 28,403 were calcium and vitamin D users and 113,744 were never users. Calcium and vitamin D significantly reduced the revision risk with a 6-month drug use lag period (adjusted hazard ratio [aHR] 0.56, 95% confidence interval [CI] 0.45-0.70). Calcium and vitamin D combination use for more than 1 year was associated with reduced revision risks in both patients with periprosthetic joint infection (aHR 0.63, 95% CI 0.42-0.95) and patients without infection (aHR 0.70, 95% CI 0.54-0.91). Implant survival was significantly improved in calcium and vitamin D combination users for more than 1 year compared with never users (log-rank P < .001). ConclusionCombination use of calcium and vitamin D with a dose of 800 IU or greater for more than 1 year was associated with the greatest reduction in the risks for revision surgery after total knee arthroplasty.

Fellow Involvement in Primary Total Knee Arthroplasty: Is There an "August Effect?"

The purpose of this study is to determine if a fellow's involvement, as well as duration of a fellow's training, impacts complications, outcomes, and survivorship in primary total knee arthroplasty (TKA). A retrospective review identified 2,790 consecutive patients (3,530 knees) who underwent primary TKA between 2003 and 2008. A 2-year minimum follow-up was available on 2,785 knees (2,195 patients). Operative data, clinical outcomes, complications, and survivorship were compared between cases with and without a fellow involved as well as comparing cases in the first quarter (Q1) of the academic year to the last three quarters (Q2-4). Mean follow-up was 9.7 years. Fellows were involved in 1,434 (41%) surgeries. Fellow cases had significantly longer tourniquet times (59.5 vs. 49 minutes, p < 0.001) and operative times (82.4 vs. 70.8 minutes, p < 0.001). Overall, there was no difference in clinical, functional, or pain outcomes between attending and fellow cases. Fellow cases during Q1 had significantly worse pain scores (p = 0.009) and clinical scores (p < 0.001). Revision rate, infection rates, and survivorship were not significantly different between fellow and attendings or during Q1 of fellowship compared with attendings. Primary TKA survivorship and complications were not affected by fellow involvement or academic quarter. An "August Effect" may be suggested for clinical and pain outcomes in the first 3 months of fellowship.

Knee haemophilic arthropathy care in Chile: Midterm outcomes and complications after total knee arthroplasty.

Total knee arthroplasty (TKA) can improve knee function in the general population, but challenges arise for TKA use in haemophilic patients (HPs). This study aimed to evaluate the midterm clinical experience of a single medical centre in TKA in HPs. We performed a case series of consecutive TKAs from 2007 to 2013 in HPs. All patients received coagulation factor supplementation according to the institutional protocol. Surgery was performed without a tourniquet by a standard midline medial parapatellar approach. We compared the range of motion (ROM) and flexion contracture before surgery and 1-year postoperative using paired Wilcoxon-non-parametric test (P<.05 was considered significant). The need for revision surgery was considered TKA survival failure. Forty-one HP/60 TKAs were reviewed (19 cases were bilateral). Preoperative median ROM and flexion contracture was 75° (range, 0°-95°) and 20° (range, 5°-80°), respectively. The postoperative median ROM increased to 83° (range, 45°-110°), and median flexion contracture decrease to 0° (range, 0°-40°) a statistically significant difference (P<.01). Postoperative median clinical Knee Society Score (KSS) and functional KSS were 88 (range, 59-97) and 100 (range, 30-100), respectively. Six patients required revision (6.66%) due to infection. TKA survival at 5years was 92% (range, 82%-96%). This study supports that TKA improves function and ROM in haemophilic knee arthropathy. The protocol of coagulation factors used in this cohort is valid as no related complications were reported. A higher incidence of complications, especially infections, must be expected compared with a TKA in non-HPs.

Accuracy of tibial positioning in the frontal plane: a prospective study comparing conventional and innovative techniques in total knee arthroplasty

BackgroundCoronal alignment of the tibial component determines functional outcome and survival in total knee arthroplasty (TKA). Innovative techniques for tibial instrumentation have been developed to improve accuracy and reduce the rate of outliers.MethodsIn a prospective study, 300 patients were allocated to four different groups using a randomization process (two innovative and two conventional) techniques of tibial instrumentation (conventional: extramedullary, intramedullary; innovative: navigation and patient-specific instrumentation (PSI); n = 75 for each group). The aims were to reconstruct the medial proximal tibial angle (MPTA) to 90° and the mechanical tibio-femoral axis (mTFA) to 0°. Both angles were evaluated and compared between all groups three months after the surgery. Patients who presented with a postoperative mTFA > 3° were classified as outliers.ResultsThe navigation and intramedullary technique both demonstrated that they were significantly more precise in reconstructing a neutral mTFA and MPTA compared to the other two techniques. The odd’s ratio (OR) for producing outliers was highest for the PSI method (PSI OR = 5.5, p < 0.05; extramedullary positioning OR = 3.7, p > 0.05; intramedullary positioning OR = 1.7, p > 0.05; navigation OR = 0.04, p < 0.05). We could only observe significant differences between pre- and postoperative MPTA in the navigation and intramedullary group. The MPTA showed a significant negative correlation with the mTFA in all groups preoperatively and in the extramedullary, intramedullary and PSI postoperatively.ConclusionThe navigation and intramedullary instrumentation provided the precise positioning of the tibial component. Outliers were most common within the PSI and extramedullary technique. Optimal alignment is dependent on the technique of tibial instrumentation and tibial component positioning determines the accuracy in TKA since mTFA correlated with MPTA pre- and postoperatively.

No difference in clinical outcome and survivorship after total knee arthroplasty with patellar resurfacing and nonresurfacing after minimum 10-year follow-up.

The study aims to evaluate the clinical outcomes and surgery survivorship for over 10 years following patellar resurfacing or nonresurfacing in total knee arthroplasty (TKA) in a cohort of Chinese patients.From 1998 to 2003, 355 patients underwent primary TKA in our institute. The survivorship of TKA between the patellar resurfacing and nonresurfacing groups and the clinical outcome of Hospital for Special Surgery knee score, Western Ontario and McMaster Universities index score, patellar score, patellar related complications, and radiological results were studied at latest follow-up.There was no statistically significant difference for the Hospital for Special Surgery score, Western Ontario and McMaster Universities score, and the patellar score between the 2 groups after an average 12.4-year follow-up. Nonresurfacing group had higher anterior knee pain than the resurfacing group (13.2% vs 5.6%). The patients with rheumatoid arthritis had a 2.9-fold higher rate of patellar-related complications than did the patients with osteoarthritis. The 10-year survival rate was not significantly different between the 2 groups both for revision surgery (P = .505) and for patellar-related complication (P = .194).There was no significant difference in the long-term clinical outcome and survivorship between patellar resurfacing and nonresurfacing. Patellar nonresurfacing could be advisable during primary TKA for osteoarthritis patients. Selective patellar resurfacing for RA patients could achieve lower patellar-related complications.

Extramedullary Guide Alignment Is not Affected by Obesity in Primary Total Knee Arthroplasty.

Coronal alignment of the tibial implant correlates with survivorship of total knee arthroplasty (TKA), especially in obese patients. The purpose of this study was to determine if obesity affects coronal plane alignment of the tibial component when utilizing standard extramedullary tibial guide instrumentation during primary TKA. A retrospective review from June 2017 to February 2018 identified 142 patients (162 primary TKAs). There were 88 patients (100 knees) with body mass index (BMI) < 35 kg/m2 and 54 patients (62 knees) with BMI ≥ 35.0 kg/m2. The cohorts did not differ in age (p = 0.37), gender (p = 0.61), or Charlson's comorbidity index (p = 0.54). Four independent reviewers measured the angle between the base of the tibial component and the mechanical axis of the tibia on the anteroposterior view of long-leg film at first postoperative clinic visit. Outliers were defined as patients with greater than 5 degrees of varus or valgus alignment (n = 0). Reoperations and complications were recorded to 90 days postoperatively. There was no significant difference in mean tibial coronal alignment between the two groups (control alignment 90.8 ± 1.2 degree versus obese alignment 90.8 ± 1.2 degree, p = 0.91). There was no difference in varus versus valgus alignment (p = 0.19). There was no difference in the number of outliers (two in each group, p = 0.73). There was no difference in rate of reoperation (p = 1.0) or complication (p = 0.51). Obesity did not affect coronal plane alignment of the tibial component when using an extramedullary guide during primary TKA in our population.

Preliminary experience with an image-free handheld robot for total knee arthroplasty: 77 cases compared with a matched control group.

Achieving an optimal limb alignment is an important factor affecting the long-term survival of total knee arthroplasty (TKA). This is the first study to look at the limb alignment and orientation of components in TKA using a novel image-free handheld robotic sculpting system. This case-controlled study retrospectively compared limb and component alignment of 77 TKAs performed with a robot (Robot-group) with a matched control group of patients who received conventional alignment with intramedular rods (Controlgroup). Alignment and component positioning was measured on full-leg weight-bearing and standard lateral X-rays by two independent observers. The image-free handheld robotic sculpting system calculated the planned and achieved mechanical axis (MA). Outliers were defined as > 3° deviation from planned alignment. Mean MA was 180.1° (SD = 1.9) in the Robot-group, compared to the Controlgroup with a mean MA of 179.1° (SD = 3.1, p = 0.028). We observed 5 outliers (6%) in the Robot-group and 14 outliers (18%, p = 0.051) in the Controlgroup. Fraction of outliers of the frontal tibial component was 0% in the Robot-group versus 8% in the Controlgroup (p = 0.038). There were no other statistical differences regarding the implant positioning between both groups. The Robot-group showed significantly less outliers compared to the conventional technique. Whether these differences are clinically relevant is questionable and should be investigated on the long term. Randomized controlled trials with larger patient series will be needed in the future to confirm our preliminary results.

Reduced survival of total knee arthroplasty after previous unicompartmental knee arthroplasty compared with previous high tibial osteotomy: a propensity-score weighted mid-term cohort study based on 2,133 observations from the Danish Knee Arthroplasty Registry

Background and purpose — Both medial unicompartmental knee arthroplasties (UKA) and high tibial osteotomies (HTO) are reliable treatments for isolated medial knee osteoarthritis. However, both may with time need conversion to a total knee arthroplasty (TKA). We conducted the largest nationwide registry comparison of the survival of TKA following UKA with TKA following HTO.Patients and methods — From the Danish Knee Arthroplasty Registry, aseptic conversions to TKA from UKA and TKA converted from HTO within the period of 1997–2018 were retrieved. The Kaplan–Meier method and the Cox proportional hazards regression were used to estimate the survival and hazard ratio (HR) for revision, considering confounding by indication utilizing propensity-score based inverse probability of treatment weighting (PS-IPTW).Results — PS-IPTW yielded a well-balanced pseudo-cohort (standard mean difference (SMD) < 0.1 for all covariates, except implant supplementation) of 963.8 TKAs following UKA and 1139.1 TKAs following HTO. The survival of TKA following UKA was significantly less than that of TKA following HTO with a 5-year estimated survival of 0.88 (95% confidence interval (CI) 0.85–0.90) and 0.94 (CI 0.93–0.96), respectively. The differences in survival corresponded to an implant-supplementation adjusted HR of 2.7 (CI 2.4–3.1) for TKA following UKA compared with TKA following HTO.Interpretation — Previous UKA more than doubled the revision risk of a subsequent TKA compared with previous HTO. This potential risk should be considered in the shared treatment decision of patients who are candidates for both UKA and HTO.

Influence du varus préopératoire sur l’alignement postopératoire et les résultats fonctionnels à long terme dans les arthroplasties totales de genou

PurposePreoperative varus deformity may affect postoperative mechanical alignment and outcomes of total knee arthroplasty (TKA). In this study, we aimed to determine whether (1) greater degrees of preoperative varus deformity increase the incidence of varus-aligned TKAs and (2) residual varus alignment improves the long-term survival rate in TKAs with preoperative varus deformity. MethodsWe retrospectively reviewed 905 primary TKAs for varus-type osteoarthritis from November 1998 to June 2009. The mean follow-up was 8.23 years (±3.47 years). We measured pre- and postoperative mechanical hip-knee-ankle axis angle (HKA) on full-length standing radiographs to assess the severity of preoperative varus deformities, defined as mild (0°<HKA≤5°), moderate (5°<HKA≤10°), severe (10°<HKA≤15°), and very severe (HKA>15°). Postoperative alignment was divided to four groups: valgus (HKA<−3°), neutral (−3°≤HKA≤3°), mild varus (3°<HKA≤6°), and severe varus (HKA>6°). We performed survival analysis in all cases for mechanical failure. ResultsVarus-aligned TKAs increased proportionally to increasing preoperative varus deformity (p<0.001). The survival rate showed no significant difference according to the preoperative varus deformity (p=0.147). However, the survival time for postoperative neutral alignment (16.13±0.10 years, 95 % CI 15.94–16.33 years) was longer than the survival time for mild varus (15.32±0.35 years, 95 % CI 14.64–16.00 years) and severe varus (13.38±0.53 years, 95 % CI 12.35–14.42 years) alignment (p<0.001). ConclusionPostoperative varus malalignment appears to increase proportionally to the severity of preoperative varus deformity. Also, postoperative neutral alignment results in longer TKA survival time than residual varus alignment. Level of evidenceIII, Retrospective comparative cohort study.

Long-Term Implant Survivorship and Modes of Failure in Simultaneous Concurrent Bilateral Total Knee Arthroplasty

BackgroundThere is limited evidence describing long-term implant survivorship and modes of failure in simultaneous concurrent bilateral total knee arthroplasty (TKA). MethodsWe performed a retrospective review of 266 consecutive patients (532 knees) who underwent simultaneous concurrent bilateral TKA. We reviewed medical records for preoperative characteristics, perioperative complications, and revision surgeries. The primary outcome was TKA survivorship. Secondary outcomes included indication and type of revision surgery. We used the Kaplan-Meier method to estimate survivorship and characterize risk of revision up to 20 years post-TKA. ResultsOur cohort had median follow-up of 9.8 years (interquartile range, 3.9-15.9). Forty-four patients (17%) underwent revision. Revision was more common among younger and male patients. The cumulative incidence of first-time revision per knee (n = 532) was 1.27 per 100 component-years. Implant survival was 99% (confidence interval, 97%-99%) at 5 years, 92% (89%-95%) at 10 years, 83% (77%-87%) at 15 years, and 62% (50%-73%) at 20 years. Five and 10-year survivorship compared favorably to estimates of TKA survivorship in the literature. The cumulative incidence of revision surgery per patient was 1.91 per 100 component-years. Implant survival at 5-, 10-, 15-, and 20-year time points was 96% (CI, 92%-98%), 84% (77%-89%), 71% (62%-79%), and 59% (46%-70%), respectively. Aseptic loosening (40%), polyethylene wear (34%), and infection (11%) were the most common indications for revision. ConclusionSimultaneous concurrent bilateral TKA is associated with a higher risk of reoperation for the patient when both knees are evaluated but similar implant survivorship to the literature when each knee was evaluated in isolation.

Impact of preoperative varus deformity on postoperative mechanical alignment and long-term results of “mechanical” aligned total knee arthroplasty

PurposePreoperative varus deformity may affect postoperative mechanical alignment and outcomes of total knee arthroplasty (TKA). In this study, we aimed to determine whether (1) greater degrees of preoperative varus deformity increase the incidence of varus-aligned TKAs and (2) residual varus alignment improves the long-term survival rate in TKAs with preoperative varus deformity. MethodsWe retrospectively reviewed 905 primary TKAs for varus-type osteoarthritis from November 1998 to June 2009. The mean follow-up was 8.23 years (±3.47 years). We measured pre- and postoperative mechanical hip-knee-ankle axis angle (HKA) on full-length standing radiographs to assess the severity of preoperative varus deformities, defined as mild (0°<HKA≤5°), moderate (5°<HKA≤10°), severe (10°<HKA≤15°), and very severe (HKA>15°). Postoperative alignment was divided to four groups: valgus (HKA<−3°), neutral (−3°≤HKA≤3°), mild varus (3°<HKA≤6°), and severe varus (HKA>6°). We performed survival analysis in all cases for mechanical failure. ResultsVarus-aligned TKAs increased proportionally to increasing preoperative varus deformity (p<0.001). The survival rate showed no significant difference according to the preoperative varus deformity (p=0.147). However, the survival time for postoperative neutral alignment (16.13±0.10 years, 95% CI 15.94–16.33 years) was longer than the survival time for mild varus (15.32±0.35 years, 95% CI 14.64–16.00 years) and severe varus (13.38±0.53 years, 95% CI 12.35–14.42 years) alignment (p<0.001). ConclusionPostoperative varus malalignment appears to increase proportionally to the severity of preoperative varus deformity. Also, postoperative neutral alignment results in longer TKA survival time than residual varus alignment. Level of evidenceIII, Retrospective comparative cohort study.

Higher Rate of Early Revision Following Primary Total Knee Arthroplasty in Patients Under Age 55: A Cautionary Tale

BackgroundThere has been an increased number of total knee arthroplasties (TKAs) performed in young and active patients. Although improved materials have decreased the likelihood of early catastrophic wear, concerns remain with the performance and survivorship of TKA implants in this patient population. The purpose this study is to evaluate perioperative complications, patient-reported outcomes, and implant survivorship of TKAs performed in patients under age 55. MethodsWe retrospectively reviewed 4259 primary TKAs performed over a 4-year period. There were 741 TKAs in patients under age 55. The primary outcome of interest was rate of revision at 30 days, 1, 2, and 5-year time points. Secondary outcomes included postoperative transfusion rate, length of stay, rate of deep vein thrombosis/pulmonary embolism, need for manipulation under anesthesia, readmission and reoperation within 30 days, as well as patient-reported outcomes. ResultsThere were 3518 patients over 55 years and 741 patients under 55 years. Overall, 175 patients required revision (4.1%). Patients under 55 years had significantly higher cumulative revision rate at 1 (3.4% vs 1.8%, P < .001), 2 (5.0% vs 2.4%, P < .001), and 5 years (7.3% vs 3.7%, P < .001). Patients under 55 years had a higher rate of early reoperation. Patients over 55 years required more transfusions and suffered a higher rate of early deep vein thrombosis. Patients over 55 years had significantly greater improvements in Patient Reported Outcome Measurement Information System Global 10 Physical scores at 6 months postoperatively compared to patients under 55 years. ConclusionsDespite improvements in TKA implants, young and active patients remained at higher risk of early revision compared to older patients. The data should be used to counsel young prospective TKA patients about the early risk of reoperation and non–wear-related complications.

Survival of total knee arthroplasty after high tibial osteotomy versus primary total knee arthroplasty: A meta-analysis.

Background:Theoretical considerations suggest that total knee arthroplasty (TKA) is technically more challenging after high tibial osteotomy (HTO), resulting in inferior results compared to primary TKA. However, several studies on this issue have shown contradictory results. The purpose of this meta-analysis to compare survivorship and clinical outcomes between TKA with and without previous HTO.Methods:We reviewed studies that evaluated pain and function scores, range of motion (ROM), operation time, Insall-Salvati (IS) ratio, complications, and survival rates in patients treated with TKA with previous HTO or with primary TKA with short- to midterm (<10 years) or long-term (>10 years) follow-up.Results:Fifteen studies were included in the meta-analysis. There were no significant differences between TKA with and without previous HTO in pain score (95% CI: −0.27 to 0.29; P = .94), function score (95% CI: −0.08 to 0.24; P = .32), operation time (95% CI: −5.43 to 26.85; P = .19), IS ratio (95% CI: −0.03 to 0.08; P = .40), complication rates (TKA with previous HTO, 62/1717; primary TKA, 610/31386; OR 1.31, 95% CI: 0.97–1.77; P = .08), and short- to midterm survival rates (TKA with previous HTO, 1860/2009; primary TKA, 37848/38765; OR 0.55, 95% CI: 0.28–1.10; P = .09). Conversely, ROM (95% CI: −7.40 to −1.26; P = .006) and long-term survival rates (TKA with previous HTO, 1426/1523; primary TKA, 29810/31201; OR 0.71, 95% CI: 0.57–0.89; P = .003) were significantly different between the two groups. In addition, both groups had substantial proportions of knees exhibiting short- to midterm survivorship (92.6% by TKA with previous HTO and 97.6% by primary TKA) and long-term survivorship (93.6% by TKA with previous HTO and 95.5% by primary TKA).Conclusions:This meta-analysis suggests that a previous HTO affected ROM or survival of TKA in the long-term even though both groups have equivalent clinical outcomes and complications. Thus, orthopedic surgeons should offer useful information regarding the advantages and disadvantages of both procedures to patients, and should provide advice on the generally higher risk of revision after TKA with previous HTO at long-term follow-up when counseling patients.

Hip-Knee-Ankle (HKA) angle modification during gait in healthy subjects

BackgroundAchieving a neutral static Hip-Knee-Ankle angle (sHKA) measured on radiographs has been considered a factor of success for total knee arthroplasty (TKA). However, recent studies have shown that sHKA seems to have no effect on TKA survivorship. sHKA is not representative of the dynamic loading occurring during gait, unlike the dynamic HKA (dHKA). Research questionThe primary objective was to see if the sHKA is predictive of the dynamic HKA (dHKA). A secondary objective was to document to what degree the dHKA changes during gait. MethodsWe analysed 3D knee kinematics during gait of a cohort of 90 healthy individuals with the KneeKG™ system. dHKA was calculated and compared with sHKA. Knees were considered “Stable” if the dHKA remained in valgus or varus for greater than 95% of the corresponding phase, and “Changer” otherwise. Patient characteristics of the Stable and Changer knees were compared to find associated factors. ResultsAbsolute variation of dHKA during gait was 10.9 ± 5.3° for the whole cohort. The variation was less for the varus knees (10.3 ± 4.8°), than for the valgus knees (12.8 ± 6.1°, p = 0.008). We found low to moderate correlations (r = 0.266 to 0.553, p < 0.001) between sHKA and dHKA values for varus knees and no significant correlation for valgus knees. Twenty two percent (36/165) of the knees were considered Changers. The proportion of knees that were Changers was 15% of the varus versus 39% of the valgus (p < 0.001). SignificanceLower limb radiographic measures of coronal alignment have limited value for predicting dynamic measures of alignment during gait.

Prior unilateral total hip arthroplasty does not influence the outcome of ipsilateral total knee arthroplasty.

To assess the influence of a prior well-functioning unilateral primary total hip arthroplasty (THA) on the functional outcome of a subsequent ipsilateral primary total knee arthroplasty (TKA). A retrospective case-control study of 92 patients older than 60years underwent unilateral primary TKA after a prior ipsilateral THA (THA-TKA group) and 92 matched patients underwent only TKA (TKA group). Clinical assessments were performed using the Knee Society Scores (KSS) and Harris Hip Score (HSS), quality of life by the Reduced Western Ontario and MacMaster Universities (WOMAC) and Short-Form 12 (SF-12) questionnaires. Radiological evaluation was also performed. Median follow-up after TKA was 7.2 (range 5-9) years. There were no significant differences between groups in baseline data at the TKA time. The mean gains in KSS were similar in both groups. At the last follow-up, there were no significant differences in WOMAC-pain or SF12-physical scores, but the WOMAC-function (p = 0.003) and SF12-mental (p = 0.018) scores were significantly better in the isolated TKA group. At the last follow-up, there were no significant differences in the radiological knee alignment or component positions. For aseptic reasons, the TKA survival at 8years in the TKA group was 95.8 (95% CI 87.8-100%), and 96.6% (95% CI 91.8-100%) in the THA-TKA group (ns). A well-functioning unilateral THA does not influence on the functional outcome of a subsequent ipsilateral TKA. This finding can help clinicians when counseling patients with hip and knee osteoarthritis. III.

Factors Associated with a Short-Term Revision of Total Knee Arthroplasty

Background: To present the short-term complications that required revision surgery on total knee arthroplasty (TKAs) performed during the 2012-2013 period. Objective: To study the relation of complication appearance and type with the prosthesis model and surgical team experience. Methods: Study of patients undergoing TKA at our center between January 2012 and June 2013. Surgical teams were stratified according to the experience of the surgeon. Two different implants were utilized for this study. The following postoperative data were collected: indication for review, time of follow-up from the intervention to the indication for review (in months) and the reason for revision. A total of 322 TKAs were performed. The follow-up time from the placement of the first prosthesis was 35.48 ± 10.23 months. A revision was indicated for 60 of the 322 implanted prostheses (18.6%). The most frequent causes were aseptic loosening in 22 cases (37.9%), and anterior pain in 19 cases (32.8%). According to the prosthetic model, 11 revisions belonged to the A model (18.3%), and 49 (81%) to the B model. These results were statistically significant (p <0.001). Odds Ratio 5.78 (95% CI: 2.87-11.62). In teams with no expert in arthroplasty, the percentage of revision for instability was 8.3%; in teams with one expert, it was 4%; and in teams with two experts, it was 0%. Discussion: There is an increase in the number of reviews in knee arthroplasty surgery. The reasons for failure of total knee arthroplasty depend on several factors, including surgical techniques, implants, demographic variants, etc. The experience of the surgeon seems to influence the number of revisions. Patellofemoral kinematics also influences the evolution of total knee arthroplasty. One of the most important factors is the trochlear groove. Although the optimal troclear design has not been established. Conclusions: The prosthetic model seems to influence the survival of total knee arthroplasty. It is preferable that the surgical team always include a surgeon with expertise in knee arthroplasty.