Are Stems Redundant in Times of Metaphyseal Sleeve Fixation?

BackgroundVarious options exist for implant fixation in revision total knee arthroplasty. One of it is direct cementless metaphyseal sleeve fixation with stems, which has shown excellent short-term and midterm results. Stemless fixation of sleeves is another fixation option for the treatment of specific bone defects; however, so far no data in larger series exist. The objective of this study was, therefore, to analyze the midterm (3-6.5 years) results of stemless sleeve fixation in a larger revision total knee arthroplasty series.MethodsIn this prospective study, 85 patients with 109 stemless sleeves have been assessed with a mean follow-up of 58.2 (36-78) months. An exclusion criterion was uncontained type II and type III defects. Analysis included clinical and radiographic assessment.ResultsThe results showed a survival rate of sleeves in 96% of the tibia (27/28) and 100% of the femur (81/81). This results in an overall survival rate of sleeves of 99% (108/109). So far, 10 patients (11.8%) underwent rerevision during the follow-up period. The main reason for failure was infection (4/85; 4.7%). Range of motion, Oxford Knee Score, Knee Society Score, and Functional Score improved significantly. Mechanical leg alignment was within the 3° corridor in all patients.ConclusionsIn cases with type I and contained type II defects, sleeves without stems are a promising option, with a survival rate of sleeves of 99% after 5 years. Also, the clinical improvement and reconstruction of leg alignment showed excellent results. In uncontained defects and type III defects, however, we do recommend using stems for additional fixation in the diaphysis. Although the midterm results are very promising, long-term data are needed.     

Is There Material Loss at the Conical Junctions of Modular Components for Total Knee Arthroplasty?

BackgroundClinical concern exists regarding fretting corrosion and material loss from taper junctions in orthopedic devices, with previous research focusing on the modular components from total hip arthroplasty. Comparatively little has been published regarding the fretting corrosion and material loss in modular knee devices. The purpose of this study is to evaluate fretting corrosion damage and quantify material loss for conical total knee arthroplasty taper interfaces.MethodsStem tapers of 166 retrieved modular knee devices were evaluated for fretting corrosion using a semiquantitative scoring method. High precision profilometry was then used to determine volumetric material loss and maximum wear depth for a subset of 37 components (implanted for 0.25-18.76 years). Scanning electron microscopy and energy-dispersive X-ray spectroscopy were used to characterize the observed damage.ResultsMild to severe fretting corrosion was observed on the majority of tapers, with 23% receiving a maximum visually determined damage score of 4. The median rate of volumetric material loss was 0.11 mm³/y (range 0.00-0.76) for femoral components (both cone and bore taper surfaces combined) and 0.01 mm³ (range 0.00-8.10) for tibial components. Greater rates of material loss were associated with mixed metal pairings. There was a strong correlation between visual fretting corrosion score and calculated material loss (ρ = 0.68, P < .001). Scanning electron microscopy revealed varying degrees of scratching, wear, fretting corrosion, and instances of cracking with morphology not consistent with fretting corrosion, wear, or fatigue.ConclusionAlthough visual evidence of fretting corrosion damage was prevalent and correlated with taper material loss, the measured volumetric material loss was low compared with prior reports from total hip arthroplasty.     

Good mid-term outcome of the rotating hinge knee in primary total knee arthroplasty – Results of a single center cohort of 106 knees with a median follow-up of 6.3 years

BackgroundThe prognosis of complex primary total knee arthroplasty (TKA) with severe deformity and ligament deficiency is not clear. There is a paucity of evidence in the current literature on treatment outcomes of the rotating hinge knee implants in primary TKA. The aim of this study was to determine the mid-term clinical, radiographic, and health-related quality of life (HRQoL) outcomes in patients who had undergone complex primary TKA using single hinged knee replacement.MethodsIn total, 106 complex primary TKAs (101 patients) were performed using the single rotating hinged knee (RHK) implant design at our institution between January 2004 and December 2013. We conducted a retrospective analysis of prospectively collected outcome data of these patients, obtaining also information on all possible revision surgeries from the Finnish Arthroplasty Register, and conducted a prospective follow-up study of all living patients.ResultsThe 10-year Kaplan-Meier survival rate of the RHK knees was 91.6% (95% CI 86.0% to 97.2%) with revision for any reason as the endpoint. Overall, eight knees (7.5 %) underwent revision surgery during the follow-up. None of the unrevised RHK knees were radiographically loose. The majority of patients evinced good clinical outcome and quality of life as measured with patient reported outcome measures.ConclusionThe hinge knee replacement which was assessed current study can be regarded as a suitable option in complex primary TKA, provided adequate attention is paid to the correct indications and patient selection.     

Patients with Dupuytren’s Contracture,Ledderhose Disease,and Peyronie’s Disease are at higher risk of arthrofibrosis following total knee arthroplasty

BackgroundTotal knee arthroplasty (TKA) is a successful treatment for patients with late stage osteoarthritis, yet arthrofibrosis remains a consistent cause of TKA failure. Dupuytren’s, Ledderhose and Peyronie’s Diseases are related conditions of increased fibroblast proliferation. The aim of this study was to identify whether an association exists between these conditions and arthrofibrosis following TKA.MethodsPatient records were queried from 2010 to 2016 using an administrative claims database to compare the rates of arthrofibrosis, manipulation under anesthesia (MUA), lysis of adhesions (LOA), and revision TKA in patients with independent chart diagnoses of Dupuytren’s Contracture, Ledderhose, or Peyronie’s Diseases versus those without. Complications were queried and compared using multivariate logistic regression.ResultsPatients with Dupuytren’s (n = 5,232) and Ledderhose (n = 50,716) had a significantly higher rate of ankylosis following TKA: 30-days (OR, 1.54; OR, 1.23), 90-days (OR, 1.20; OR, 1.24), 6-months (OR, 1.23; OR, 1.23), and 1-year (OR, 1.28; OR, 1.23), while patients with Peyronie’s (n = 1,186) had a higher rate of diagnosis at 6-months (OR, 1.37) and 1-year (OR, 1.35). Patients with diagnoses of any of the fibroproliferative diseases had a statistically higher risk of MUA at 90-days, 6-month, and 1-year following primary TKA. These cohorts did not have a significantly higher rate of revision TKA.ConclusionThere is an increased odds risk of arthrofibrosis and MUA in patients who have undergone TKA and have a diagnosis of Dupuytren’s Contracture, Ledderhose, or Peyronie’s Diseases. Improvements to frequency and application of post-operative treatment should be considered in these cohorts to improve outcomes.     

Primary Total Knee Arthroplasty Implants as Functional Prosthetic Spacers for Definitive Management of Periprosthetic Joint Infection: A Multicenter Study

BackgroundThere are limited data on the utility of a standard primary total knee arthroplasty (TKA) femoral component with an all polyethylene tibia as a functional prosthetic spacer in place of a conventional all cement spacer for the management of periprosthetic joint infection (PJI). The aim of this multicenter study was to retrospectively review (1) ultimate treatment success; (2) reimplantation rates; (3) reoperation rates; and (4) change in knee range of motion in patients managed with functional prosthetic spacers following TKA PJI.MethodsA retrospective review was performed for patients at 2 tertiary care centers who underwent a functional prosthetic spacer implantation as part of a functional single-stage (n = 57) or all cement spacer conventional two-stage (n = 137) revision arthroplasty protocol over a 5-year period. Outcomes including reinfection, reimplantation, and reoperation rates, success rate as defined by the Delphi criteria, and final range of motion were compared between the 2 cohorts at a minimum of 2-year follow-up.ResultsThere was no significant difference in reinfection (14.0 vs 24.1%), reoperation (19.3 vs 27.7%), or success rates (78.9 vs 70.8%; P > .05 for all) between the one-stage and two-stage revision TKA cohorts. Mean final total arc of motion was also similar between the 2 groups (105.8 vs 101.8 degrees, respectively).ConclusionFunctional prosthetic spacers offer the advantage of a single procedure with decreased overall hospitalization and improved cost-effectiveness with analogous success rates (78.9%) compared with two-stage exchange (70.8%) at mid-term follow-up. Although long-term data are required to determine its longevity and efficacy, the outcomes in this study are encouraging.Level of Evidence3.     

Cross-Cultural Adaptation,Reliability, and Validity of the Chinese Version of the Tampa Scale for Kinesiophobia-11 Among Patients Who Have Undergone Total Knee Arthroplasty

BackgroundThe shortened version of the Tampa Scale for Kinesiophobia (TSK-11) has been well characterized in the literature. However, to the best of our knowledge, no previous studies have evaluated the reliability and validity of the TSK-11 for Chinese-speaking patients who have undergone total knee arthroplasty (TKA). Thus, the objectives of this study were to translate and adapt the TSK-11 cross-culturally into Chinese and to evaluate its reliability and validity in a sample of Chinese TKA patients.MethodsThe TSK-11 was translated and cross-culturally adapted into Chinese according to the international guidelines for the cross-cultural adaptation of self-report measures. The Chinese version of TSK-11 was administered to 254 patients following their TKA, along with the Fear-Avoidance Beliefs Questionnaire, Pain Catastrophizing Scale, Numerical Rating Scale, and 12-Item Short Form Health Survey. Psychometric testing included internal consistency, test-retest reliability, floor and ceiling effects, construct validity, and convergent validity.ResultsA high completion rate of 95.8% with no floor or ceiling effects was noted in the Chinese version of the TSK-11. The questionnaire also showed good internal consistency (Cronbach’s α = 0.883) and test-retest reliability (intraclass correlation coefficient = 0.798). Construct validity was assessed by exploratory factor analysis, and 3 factors were extracted that accounted for 65.2% of the variance. Convergent validity was confirmed by significant Pearson correlations between the Chinese version of the TSK-11 and the Pain Catastrophizing Scale (r = 0.751), Fear-Avoidance Beliefs Questionnaire (r = 0.719) and VAS (r = 0.450), as well as the 12-Item Short Form Health Survey subdomains Bodily Pain (r = ?0.391), Mental Health (r = ?0.356), Physical Functioning (r = ?0.339), Role-Emotional (r = ?0.317), and Role-Physical (r = ?0.277).ConclusionThe Chinese version of the TSK-11 demonstrated satisfactory acceptability, reliability, and validity; therefore, it can be used in clinical practice and research for assessing kinesiophobia in Chinese patients after TKA.     

Accuracy and Cost-Effectivenss of a Novel Method for Alpha Defensins Measurement in the Diagnosis of Periprosthetic Joint Infections

BackgroundTwo methods for detecting synovial fluids alpha defensins are available: the enzyme-linked immunosorbent assay and the lateral flow test. For both, the proper role and accuracy remain uncertain. The purpose of this study was to assess the accuracy of the matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) for alpha defensin detection in synovial fluids of patients with total knee arthroplasty/total hip arthroplasty failures. The hypothesis was that the alpha defensin measurement through MALDI-TOF MS assay could be a high sensitive and specific test for periprosthetic joint infections (PJI) diagnosis as compared with Musculoskeletal Infection Society (MSIS) criteria.MethodsThe study included 138 patients. The 2018 MSIS criteria were used to diagnose PJIs. Synovial fluids were assessed for routinely synovial fluid tests and alpha defensin measurement through MALDI-TOF MS. Sensitivity, specificity, overall diagnostic accuracy, positive and negative predictive values, receiver operator curves, and area under the curve were calculated.ResultsAs per the 2018 MSIS criteria, 59 PJIs (43%) and 79 aseptic failures (57%) were diagnosed. The MALDI-TOF MS assay showed an overall accuracy of 94.9%. The sensitivity was 93%, the specificity was 96%, the positive predictive value was 95%, and the negative predictive value was 95%. Receiver operator curves analysis demonstrates an area under the curve of 0.95 (P < .001).ConclusionThe MALDI-TOF MS assay showed high sensitivity and specificity for alpha defensin detection in case of total knee arthroplasty/total hip arthroplasty failures. The advantages of the technology, such as the few milliliters of sample needed, the rapidity of obtaining results, and the cost-effectiveness of the procedure could make the MALDI-TOF MS alpha defensin assay a useful and widespread test in clinical practice.     

Intraoperative Practice Variability in Total Knee Arthroplasty

BackgroundConsiderable practice variability exists among orthopedic surgeons performing total knee arthroplasty (TKA). The purpose of this study is to understand what TKA surgical and perioperative techniques are standard among high-volume academic knee arthroplasty surgeons.MethodsA written survey with 59 questions regarding management preferences in TKA was distributed by the 2018 John N. Insall Traveling Fellows to all arthroplasty-trained attending physicians at 13 medical centers, with 45 responses recorded.ResultsSurveyed surgeons performed unicompartmental knee arthroplasty (88%) and bilateral TKA (87%). Most surveyed surgeons rarely or never performed outpatient primary TKA (71%). Conventional alignment guides and cemented implants were used by 80% of respondents. Most surgeons used posterior-stabilized implants (67%), followed by cruciate-retaining (20%), ultracongruent (20%), and medial congruent or medial pivot designs (17.8%). Surveyed surgeons frequently or always resurfaced the patella (73%), used a tourniquet for the entire case (73%), and used tranexamic acid for all TKAs (91%). The most common locations for intra-articular anesthetic injection were the arthrotomy (91%), the periosteum (84%), and the medial posterior capsule (82%). Saline (62%) and dilute iodine (47%) were the most common irrigation fluids. The arthrotomy was most commonly closed with running barbed suture (60%) followed by interrupted vicryl (40%). Skin closure was predominantly with running monocryl (60%) followed by staples (29%). Anticoagulation for TKA was primarily aspirin 81 mg BID (60%).ConclusionThere was considerable variability among surgeons polled although a strong preference for more conventional and less developmental techniques prevailed.     

Comparison of Tip- Versus Hub-Oscillating Saw Blade Control in a Total Knee Arthroplasty Model

BackgroundOscillating saws are commonly used for bone preparation in total knee arthroplasty but can cause injury to the posterior neurovascular bundle during tibial resection. Tip-oscillating saw blades are a recent innovation that could improve saw control due to decreased excursion; however, the tactile feedback to the surgeon is different.MethodsTo compare traditional hub and new tip-oscillating saw blades, 16 participants of varying levels of experience were video-recorded during composite tibial bone model resections to measure posterior saw blade plunge. Subjective perceptions of saw control and preference were also surveyed.ResultsSaw blade design and level of surgical experience did not produce a significant difference in posterior saw blade plunge (P > .05). Independent of saw blade design, subjects with no previous saw experience had significantly decreased posterior tibial plunge over subsequent resections. Tip-oscillating saw blades were perceived to be easier to use and control by less experienced participants (P = .0163).ConclusionTip-oscillating saw blades do not alter the risk of posterior tibial saw plunge compared with traditional saw blades.