Evaluation of Appropriateness of the Reimbursement Criteria of Korean Health Insurance Review and Assessment Service for Total Knee Arthroplasty.

Background: We evaluated and compared South Korea's total knee arthroplasty (TKA) reimbursement criteria set by Health Insurance Review and Assessment Service (HIRA) with other TKA appropriateness criteria to find additional criterion to improve its appropriateness by reviewing TKA inappropriate cases. Methods: Two TKA appropriateness criteria and HIRA's reimbursement criteria for TKA were adapted for use on patients undergoing TKA in one institute from December 2017 to April 2020. Preoperative data including 9 validated questionnaires on knee joint-specific parameters, age, and radiography were used. We categorized cases into appropriate, inconclusive, inappropriate groups and analyzed each group. Results: Data on 448 cases that underwent TKA were examined. According to the HIRA's reimbursement criteria, 434 cases (96.9%) were appropriate and 14 cases (3.1%) were inappropriate; superior to other TKA appropriateness criteria. The inappropriate group had Knee Injury and Osteoarthritis Outcome score (KOOS) pain, KOOS symptoms, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score, and Korean Knee score total score with worse symptoms compared to the appropriate group classified by HIRA's reimbursement criteria. Conclusions: In terms of insurance coverage, HIRA's reimbursement criteria was more effective in providing healthcare access to patients who had the most pressing need for TKA compared to other TKA appropriateness criteria. However, we found the lower age limit and patient-reported outcome measures of other criteria as useful tools in improving appropriateness of the current reimbursement criteria.

The additional tibial stem extension is not mandatory for the stability of 5 mm metal block augmented tibial prosthesis construct in primary total knee arthroplasty: 5-year minimum follow-up results.

PURPOSE: To determine whether additional stem extension for stability is necessary, we performed mid-term follow-up of patients who had been managed with 5-mm metal block augmentation for a tibial defect, where tibial prosthesis was fixed using bone cement without stem extension. Also, we evaluated clinical and radiologic results including survival rate of patients without stem extension. METHODS: We retrospectively analyzed patients with tibial bone defect, had undergone primary total knee arthroplasty, and had been treated with 5-mm metal block augmentation without stem extension between March 2003 and September 2013. Among 74 patients (80 cases), 47 patients (52 cases) were followed up for at least 5 years. RESULTS: Mean flexion contracture improved from 8.8° (0-40°) preoperatively to 0.4° (-5° to 15°) at final follow-up (P < 0.01), but there was no significant change in the mean angle of great flexion: 124.6° (75-150°) preoperatively and 126.2° (90-145°) at final follow-up (P = 0.488). Mean range of motion improved from 115.8° (35-150°) preoperatively to 125.5° (90-145°) at final follow-up (P < 0.01). Mean knee score improved from 38.7 points (0-66 points) preoperatively to 93.2 points (79-100 points) at final follow-up (P < 0.01), and mean functional score also improved from 50.4 points (10-70 points) preoperatively to 81.8 points (15-100 points) at final follow-up (P < 0.01). The mean postoperative Western Ontario and McMaster University osteoarthritis score was 19.5 points (0-66.0 points). The mean femorotibial angle was corrected from 9.0° varus (23.0° varus-6.3° valgus) preoperatively to 5.5° valgus (2.2° varus-11.1° valgus) at final follow-up (P < 0.01). There was no change in the mean ß-angle, which was 90.7° (87.2-94.9°) immediately postoperative and 90.8° (87.2-94.9°) at final follow-up (P = 0.748) and in the mean δ-angle, which was 86.2° (81.3-90.0°) immediately postoperative and 87.2° (83.1-96.5°) at final follow-up (P = 0.272). Radiolucent lines (RLL) were observed in ten cases (26.3%), and the mean RLL scores at final follow-up were 0.34 points (0-3 points) in the anteroposterior view and 0.42 points (0-6 points) in the lateral view. Scores for the RLL were ≤ 4 points in 36 cases, 5-9 points in two cases. Revision surgery due to aseptic loosening (three cases) is rarely required, and the Kaplan-Meier survival rate at 10 postoperative years was 96.4% CONCLUSION: When performing 5-mm metal block augmentation for a proximal tibial defect, no additional tibial stem extension can be a good surgical option for the stability of tibial prosthetic construct and mid-term clinical and radiologic results. LEVEL OF EVIDENCE: IV.

Comparison of Clinical Outcomes after Total Knee Arthroplasty with and without Patellar Resurfacing in the Same Patients.

Background: Patellar resurfacing is performed in total knee arthroplasty (TKA) to improve pain in the anterior compartment of the knee joint and to restore proper coordination and movement of the patellofemoral joint. The purpose of this study was to analyze differences in clinical outcomes according to patellar resurfacing in patients who underwent bilateral TKA. Methods: Forty-three patients who underwent bilateral primary TKA with patellar resurfacing on one side only were included. Patellar resurfacing was performed selectively according to the status of the patella cartilage surface. Knee Society score (knee and function), Feller score, Kujala score, and Samsung Medical Center (SMC) score (pain and function) were evaluated. Results: There were no significant differences in Knee Society pain and function scores, Feller score, Kujala score, and SMC pain and function scores according to patellar resurfacing. On the comparison of SMC scores, there was no difference except for two questions. Conclusions: It is advisable not to perform resurfacing on normal patellae. However, in order to apply this result to damaged patellae, comparative studies between resurfaced patellae and damaged patellae are needed.

Allogeneic Umbilical Cord Blood-Derived Mesenchymal Stem Cell Implantation Versus Microfracture for Large, Full-Thickness Cartilage Defects in Older Patients: A Multicenter Randomized Clinical Trial and Extended 5-Year Clinical Follow-up.

BACKGROUND: There is currently no optimal method for cartilage restoration in large, full-thickness cartilage defects in older patients. PURPOSE: To determine whether implantation of a composite of allogeneic umbilical cord blood-derived mesenchymal stem cells and 4% hyaluronate (UCB-MSC-HA) will result in reliable cartilage restoration in patients with large, full-thickness cartilage defects and whether any clinical improvements can be maintained up to 5 years postoperatively. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A randomized controlled phase 3 clinical trial was conducted for 48 weeks, and the participants then underwent extended 5-year observational follow-up. Enrolled were patients with large, full-thickness cartilage defects (International Cartilage Repair Society [ICRS] grade 4) in a single compartment of the knee joint, as confirmed by arthroscopy. The defect was treated either with UCB-MSC-HA implantation through mini-arthrotomy or with microfracture. The primary outcome was proportion of participants who improved by ≥1 grade on the ICRS Macroscopic Cartilage Repair Assessment (blinded evaluation) at 48-week arthroscopy. Secondary outcomes included histologic assessment; changes in pain visual analog scale (VAS) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and International Knee Documentation Committee (IKDC) score from baseline; and adverse events. RESULTS: Among 114 randomized participants (mean age, 55.9 years; 67% female; body mass index, 26.2 kg/m2), 89 completed the phase 3 clinical trial and 73 were enrolled in the 5-year follow-up study. The mean defect size was 4.9 cm2 in the UCB-MSC-HA group and 4.0 cm2 in the microfracture group (P = .051). At 48 weeks, improvement by ≥1 ICRS grade was seen in 97.7% of the UCB-MSC-HA group versus 71.7% of the microfracture group (P = .001); the overall histologic assessment score was also superior in the UCB-MSC-HA group (P = .036). Improvement in VAS pain, WOMAC, and IKDC scores were not significantly different between the groups at 48 weeks, however the clinical results were significantly better in the UCB-MSC-HA group at 3- to 5-year follow-up (P < .05). There were no differences between the groups in adverse events. CONCLUSION: In older patients with symptomatic, large, full-thickness cartilage defects with or without osteoarthritis, UCB-MSC-HA implantation resulted in improved cartilage grade at second-look arthroscopy and provided more improvement in pain and function up to 5 years compared with microfracture. REGISTRATION: NCT01041001, NCT01626677 (ClinicalTrials.gov identifier).

National Trends of Meniscectomy and Meniscus Repair in Korea.

BACKGROUND: Meniscus surgeries are frequently performed in orthopaedics. However, their current status is not well known in many countries, including Korea. This study aimed to investigate the national trends of meniscus surgery in Korea. METHODS: Information from the national database was acquired through the Korean Health Insurance Review and Assessment Service from 2010 to 2017. All cases coded as meniscectomy or meniscus repair were included. The total number and incidence of cases of meniscus surgery per 100,000 persons were determined, and the results were stratified by age and gender. The meniscus repair ratio for the total number of meniscus surgeries was evaluated. RESULTS: The total number and incidence of meniscectomy cases were 65,752 and 137, respectively, in 2010, which increased to 74,088 and 154, respectively, in 2017. The number of meniscectomies increased by 12.67% in 8 years. The total number and incidence of meniscus repair cases were 9,055 and 18, respectively, in 2010, which increased to 14,947 and 31 in 2017. The number of meniscus repairs increased by 65.04%. The meniscus repair ratio was 12.1% in 2010, which increased to 16.8% in 2017. The highest peak was noted for patients who underwent meniscus surgeries in their 50s and 60s. Meniscectomy was performed more frequently in women (57%) than in men (43%), whereas repair was performed more frequently in men (54%) than in women (46%) over the study period. CONCLUSION: The total number and incidence of meniscus surgeries increased from 2010 to 2017; the number and incidence of meniscus repair procedures increased more rapidly than those of meniscectomy, with the peak treatment age for both surgeries being in the 50s and 60s. The current study will contribute to understanding the epidemiology of meniscus surgery, its prevention, and cost-saving measures in Korea.

Rivaroxaban and Acetylsalicylic Acid for Prevention of Venous Thromboembolism Following Total Knee Arthroplasty in Korean Patients.

PURPOSE: To investigate the incidence of venous thromboembolism (VTE) after total knee arthroplasty (TKA) with chemoprophylaxis using acetylsalicylic acid (AA) or rivaroxaban in Korean patients. MATERIALS AND METHODS: Between May 2011 and November 2013, 268 TKA patients (330 cases) were randomly allocated to 3 groups (group A: subcutaneous injection of 5,000 IU low-molecular-weight heparin for 2 days followed by oral administration of 100 mg AA for 5 days; group X7: oral administration of 10mg rivaroxaban for 7 days; and group X10: oral administration of 10 mg rivaroxaban for 10 days). Multidetector-row computed tomography (MDCT) was performed at 10 days and 3 months postoperatively to evaluate VTE changes. RESULTS: The VTE incidence was 38.2%, 20.0%, and 10.0% in groups A, X7, and X10, respectively (p＜0.001). Pulmonary embolism (PE) was identified in 19.1%, 10.0%, and 2.7% in groups A, X7, and X10, respectively (p＜0.001). Proximal or symptomatic deep vein thrombosis (DVT) occurred primarily in group A, but the incidence was not significantly different among groups. On follow-up MDCT, PE was resolved completely with treatment in 29/30 (96.7%), and so was asymptomatic distal DVT in 24/27 (88.8%) without treatment. CONCLUSIONS: Rivaroxaban had a lower incidence of overall VTE than AA, but no difference was observed in symptomatic VTE. The 10-day course of rivaroxaban had a lower incidence of overall VTE than the 7-day course.

A Multicenter, Double-Blind, Phase III Clinical Trial to Evaluate the Efficacy and Safety of a Cell and Gene Therapy in Knee Osteoarthritis Patients.

The aim of this study was to test the clinical efficacy of TissueGene-C (TG-C), a cell and gene therapeutic for osteoarthritis consisting of non-transformed and transduced chondrocytes (3:1) retrovirally transduced to overexpress transforming growth factor-ß1. A total of 163 Kellgren-Lawrence grade 3 patients with knee osteoarthritis were randomly assigned to receive intra-articular TG-C or placebo. Primary efficacy measures included criteria for subjective assessment by International Knee Documentation Committee (IKDC) and pain severity by Visual Analog Scale (VAS) for 52 weeks. Secondary efficacy measures included IKDC and VAS at 26 and 39 weeks; pain, stiffness, and physical function by the Western Ontario and McMaster Universities Arthritis Index (WOMAC); and pain, symptoms, daily activities, function in sports and recreation, and quality of life by the Knee Injury and Osteoarthritis Outcome Score (KOOS), X-ray, magnetic resonance imaging, and soluble urine and blood biomarkers. TG-C was associated with statistically significant improvement over placebo in the total IKDC score and individual categories, and in the VAS score at 26, 39, and 52 weeks. WOMAC and KOOS scores also improved with TG-C over placebo. Patients treated with TG-C showed trends directed toward thicker cartilage and slower growing rates of subchondral bone surface area in the medial tibia, lateral tibia, lateral patella, and lateral patella femoral regions, although these were not statistically significant (p > 0.05). Serum C-terminal telopeptide of type I collagen (CTX-I) and urine CTX-II levels were lower over 1 year in TG-C than placebo-treated patients, with CTX-I level reaching statistical significance. These tendencies supported TG-C as holding great potential as a disease-modifying osteoarthritis drug. The most frequent adverse events in the TG-C group were peripheral edema (9%), arthralgia (8%), joint swelling (6%), and injection site pain (5%). TG-C was associated with statistically significant improvements in function and pain in patients with knee osteoarthritis. The unexpected adverse events were not observed.

Comparison of Tibiofemoral Contact Mechanics After Various Transtibial and All-Inside Fixation Techniques for Medial Meniscus Posterior Root Radial Tears in a Porcine Model.

PURPOSE: To compare tibiofemoral contact mechanics after fixation for medial meniscus posterior root radial tears (MMPRTs). METHODS: Seven fresh knees from mature pigs were used. Each knee was tested under 5 conditions: normal knee, MMPRT, pullout fixation with simple sutures, fixation with modified Mason-Allen sutures, and all-inside fixation using Fastfix 360. The peak contact pressure and contact surface area were evaluated using a capacitive sensor positioned between the meniscus and tibial plateau, under a 1,000-N compression force, at different flexion angles (0°, 30°, 60°, and 90°). RESULTS: The peak contact pressure was significantly higher in MMPRTs than in normal knees (P = .018). Although the peak contact pressure decreased significantly after fixation at all flexion angles (P = .031), it never recovered to the values noted in the normal meniscus. No difference was observed among fixation groups (P = .054). The contact surface area was significantly lower in MMPRTs than in the normal meniscus (P = .018) and increased significantly after fixation at all flexion angles (P = .018) but did not recover to within normal limits. For all flexion angles except 60°, the contact surface area was significantly higher for fixation with Mason-Allen sutures than for fixation with simple sutures or all-inside fixation (P = .027). At 90° of flexion, the contact surface area was significantly better for fixation with simple sutures than for all-inside fixation (P = .031). CONCLUSIONS: The peak contact pressure and contact surface area improved significantly after fixation, regardless of the fixation method, but did not recover to the levels noted in the normal meniscus after any type of fixation. Among the fixation methods evaluated in this time 0 study, fixation using modified Mason-Allen sutures provided a superior contact surface area compared with that noted after fixation using simple sutures or all-inside fixation, except at 60° of flexion. However, this study had insufficient power to accurately detect the differences between the outcomes of various fixation methods. CLINICAL RELEVANCE: Our results in a porcine model suggest that fixation can restore tibiofemoral contact mechanics in MMPRT and that fixation with a locking mechanism leads to superior biomechanical properties.

A Randomized, Multicenter, Phase III Trial to Evaluate the Efficacy and Safety of Polmacoxib Compared with Celecoxib and Placebo for Patients with Osteoarthritis.

BACKGROUND: The aim of this study was to evaluate the safety and analgesic efficacy of polmacoxib 2 mg versus placebo in a superiority comparison or versus celecoxib 200 mg in a noninferiority comparison in patients with osteoarthritis (OA). METHODS: This study was a 6-week, phase III, randomized, double-blind, and parallel-group trial followed by an 18-week, single arm, open-label extension. Of the 441 patients with knee or hip OA screened, 362 were randomized; 324 completed 6 weeks of treatment and 220 completed the extension. Patients were randomized to receive oral polmacoxib 2 mg (n = 146), celecoxib 200 mg (n = 145), or placebo (n = 71) once daily for 6 weeks. During the extension, all participants received open-label polmacoxib 2 mg. The primary endpoint was the change in Western Ontario and McMaster Universities (WOMAC)-pain subscale score from baseline to week 6. Secondary endpoints included WOMAC-OA Index, OA subscales (pain, stiffness, and physical function) and Physician's and Subject's Global Assessments at weeks 3 and 6. Other outcome measures included adverse events (AEs), laboratory tests, vital signs, electrocardiograms, and physical examinations. RESULTS: After 6 weeks, the polmacoxib-placebo treatment difference was -2.5 (95% confidence interval [CI], -4.4 to -0.6; p = 0.011) and the polmacoxib-celecoxib treatment difference was 0.6 (CI, -0.9 to 2.2; p = 0.425). According to Physician's Global Assessments, more subjects were "much improved" at week 3 with polmacoxib than with celecoxib or placebo. Gastrointestinal and general disorder AEs occurred with a greater frequency with polmacoxib or celecoxib than with placebo. CONCLUSIONS: Polmacoxib 2 mg was relatively well tolerated and demonstrated efficacy superior to placebo and noninferior to celecoxib after 6 weeks of treatment in patients with OA. The results obtained during the 18-week trial extension with polmacoxib 2 mg were consistent with those observed during the 6-week treatment period, indicating that polmacoxib can be considered safe for long-term use based on this relatively small scale of study in a Korean population. More importantly, the results of this study showed that polmacoxib has the potential to be used as a pain relief drug with reduced gastrointestinal side effects compared to traditional nonsteroidal anti-inflammatory drugs for OA.

Efficacy and safety of single injection of cross-linked sodium hyaluronate vs. three injections of high molecular weight sodium hyaluronate for osteoarthritis of the knee: a double-blind, randomized, multi-center, non-inferiority study.

BACKGROUND: This randomized, double-blind, multi-center, non-inferiority trial was conducted to assess the efficacy and safety of a cross-linked hyaluronate (XLHA, single injection form) compared with a linear high molecular hyaluronate (HMWHA, thrice injection form) in patients with symptomatic knee osteoarthritis. METHODS: Two hundred eighty seven patients with osteoarthritis (Kellgren-Lawrence grade I to III) were randomized to each group. Three weekly injections were given in both groups but two times of saline injections preceded XLHA injection to maintain double-blindness. Primary endpoint was the change of weight-bearing pain (WBP) at 12 weeks after the last injection. Secondary endpoints included Western Ontario and McMaster Universities Osteoarthritis index; patient's and investigator's global assessment; pain at rest, at night, or in motion; OMERACT-OARSI responder rate; proportion of patients achieving at least 20 mm or 40% decrease in WBP; and rate of rescue medicine use and its total consumption. RESULTS: Mean changes of WBP at 12 weeks after the last injection were -33.3 mm with XLHA and -29.2 mm with HMWHA, proving non-inferiority of XLHA to HMWHA as the lower bound of 95% CI (-1.9 mm, 10.1 mm) was well above the predefined margin (-10 mm). There were no significant between-group differences in all secondary endpoints. Injection site pain was the most common adverse event and no remarkable safety issue was identified. CONCLUSIONS: This study demonstrated that a single injection of XLHA was non-inferior to three weekly injections of HMWHA in terms of WBP reduction, and supports XLHA as an effective and safe treatment for knee osteoarthritis. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT01510535 ). This trial was registered on January 6, 2012.

Measurement of change on medial and lateral joint gaps by navigation system in multi-radius PS TKA.

BACKGROUND: The purpose of this study was to evaluate the joint gap kinematics in posterior-stabilized total knee arthroplasty (PS TKA). METHODS: Between January 2010 and April 2011, 44 consecutive patients (55 knees) who underwent primary PS TKA using the navigation system were assessed. There were 37 women and 7 men with a mean age at operation of 63 years (range; 58-73 years). After fixation of all components with cement and insertion of polyethylene trial insert, medial and lateral joint gap measurements were carried out without distraction force and separately using a navigation system on each flexion angles. The joint gaps were measured before and after deflation of tourniquet, first with patella everted and then reduced. RESULTS: Deflation of tourniquet did not effect on gap. In patellofemoral joint reduction situation, the medial gap relatively maintained throughout the range of knee motion, but the lateral gap is gradually decreasing with knee flexion from 30° to 120° flexion. However, in patellar eversion situation, the medial gap showed a significant increase and also statistically significantly increased compared with patellar reduced position over 90° knee flexion status, but the lateral gaps are decreased compared with patellofemoral reduction situation throughout the range of knee motion except full flexion status. In more physiologic status that is patella reduced and tourniquet deflated status, the average medial joint gap change was 2.30 ± 1.64 mm and the average lateral joint gap change was 2.90 ± 1.53 mm throughout the range of motion. CONCLUSIONS: Medial and lateral joint gaps showed different patterns with patellar eversion and patellofemoral joint reduction. However, such changes occurred within 3 mm in average throughout whole range of knee motion even with multi-radius femoral component.

Should the position of the patellar component replicate the vertical median ridge of the native patella?

BACKGROUND: In total knee arthroplasty (TKA), the position of the patellar component can affect patellar tracking. However, the patellar component cannot always replicate the original high point of the patella because of anatomical variance. This study investigated whether altering the highest point of the patella can affect outcomes of primary TKA, especially in patients having a patella with a far-medialized median ridge. METHODS: A retrospective review was performed for 177 knees (143 patients) treated with primary TKA between July 2011 and March 2014. Group 1 (34 knees) had the patellar component displaced over three millimeters from the median ridge, while Group 2 (143 knees) had the patellar component placed on the original median ridge position. The one-year follow-up outcomes were reviewed, including: patellar tilt angle, Knee Society Score, Feller Patellar Score, and modified Kujala Anterior Knee Pain Score. RESULTS: Mean (±standard deviation) displacement of the patellar component in Group 1 was 3.97±0.97mm lateral to the original position of the median ridge, with a significant decrease in lateral patellar tilt angle (P<0.001). Lateral patellar tilt showed a positive correlation with the medialization of the patellar component (P<0.001, r=0.401). Ability to rise from a chair was better in Group 1 (P=0.025). There were no other between-group differences in other clinical outcomes. CONCLUSIONS: There should be no need for the patellar component to replicate the original highest point of the native patella in primary TKA.

The Effects of Adherence to Non-Steroidal Anti-Inflammatory Drugs and Factors Influencing Drug Adherence in Patients with Knee Osteoarthritis.

We aimed to compare the clinical outcomes of knee osteoarthritis patients according to drug adherence; and to find out the factors the affecting those outcomes. We analyzed the drug adherence and clinical outcomes in 1,334 primary knee osteoarthritis patients who took non-steroidal anti-inflammatory drugs (NSAIDs) for 3 weeks. Clinical outcomes of Pain Numeric Rating Scale (NRS), Knee injury and Osteoarthritis Outcome Score (KOOS) and EQ-5D were compared at baseline and 3 weeks' follow-up between the two groups of adherent group and non-adherent group (1,167 vs. 167 patients). Logistic regression analysis was performed to examine the factors affecting the adherence, and the reasons for the non-adherence were asked. The follow-up clinical outcomes of NRS and KOOS symptom, pain and activity of daily life were significantly higher in the adherence group (P = 0.003, P = 0.048, P = 0.005, and P = 0.003, respectively). The adherence was better in the elderly and in the male group (P = 0.042 and P = 0.034, respectively) and the top reason for no strict adherence was "symptom improved" (21.5%) followed by side effects. In this study, the patients with better adherence to NSAIDs showed better outcomes compared to those with poor adherence. This study can contribute to the patient education for the pharmacological treatment in knee OA patients.

Double metal tibial blocks augmentation in total knee arthroplasty.

PURPOSE: Severe uncontained tibial bone defects occurring during total knee arthroplasty are challenging, and which treatment method is the best remains unknown. In this study, clinical and radiographic outcomes of double metal blocks augmentation were examined. METHODS: Between 2004 and 2012, double metal blocks augmentation was carried out in 17 patients with severe asymmetric uncontained tibial bone defects. The first block was attached to the tibial tray with screws, and then the second block was cemented to the first block. Out of 17 patients, 13 (8 primary, 5 revision) were available for final follow-up at a median of 69 months (range 24-99). For clinical assessment, range of motion and Knee Society score were evaluated preoperatively and annually thereafter. At the final follow-up, Western Ontario and McMaster Universities Osteoarthritis Index, Oxford knee, Short Form-36, Lower extremity functional scale, and Lower extremity activity scale scores were evaluated. Radiographic assessment for radiolucent lines at the block-cement-bone interfaces and signs of failure was performed annually using fluoroscopy and standard radiographs. RESULTS: Range of motion and Knee Society score were significantly improved post-operatively. Other clinical outcomes were favourable. Radiolucent lines were seen on fluoroscopy in three knees, but no sign of failure, such as loosening, collapse, or instability, was observed at the final follow-up. CONCLUSIONS: Double metal blocks augmentation is a favourable and useful method, which does not cause mechanical failure or protrusion of the prosthetic because of its modularity, to manage severe asymmetric uncontained proximal tibial bone defects >15 mm in total knee arthroplasty. LEVEL OF EVIDENCE: Case series, Level IV.

Long-term results of cruciate-retaining total knee replacement in patients with rheumatoid arthritis: a minimum 15-year review.

BACKGROUND: There is controversy about whether to retain or excise the posterior cruciate ligament in rheumatoid knees because attenuation of the ligament is often present in this subgroup of patients. We reviewed more than 15 years of results of cruciate-retaining total knee replacements (TKRs) in patients with rheumatoid arthritis. METHODS: We reviewed patients' charts and radiographs to evaluate knee range of motion and flexion contractures, component loosening and osteolysis at the bone-cement interface. Our primary outcome was revision of a femoral or tibial component for any reason, and the secondary outcome was revision for any reason and periprosthetic fracture during the follow-up period. RESULTS: Our study included 112 patients (7 men, 105 women, 176 knees). Their mean age was 49.3 (range 33-64) years. Twenty-one patients died and 16 were lost to follow-up, leaving 75 patients (119 knees) with a minimum follow-up of 15 (mean 16.1) years for our analysis. Of these, 61 patients (101 knees) were available for clinical and radiological evaluation at the final follow-up assessment. At a mean of 12.2 (range 6-16) years, revision was necessary in 14 patients (19 knees), including 1 patient with an infection. Eleven patients (11 knees) had periprosthetic fractures at a mean of 11.4 (range 5-14) years after the index operation. The survival rate, with the end point being revision of the femoral or tibial component for any reason, was 98.7% at 10 years and 83.6% at 17 years. The survival rate of revision and periprosthetic fracture was 97.6% at 10 years and 76.9% at 17 years. CONCLUSION: Special attention should be paid to component loosening or periprosthetic fracture after more than 10 years of follow-up in this subgroup of patients.

CONTEXTE: On ne s'entend pas sur la nécessité de conserver ou d'exciser le ligament croisé postérieur dans les genoux rhumatoïdes en raison de l'affaiblissement du ligament, souvent présent chez cette catégorie de patients. Nous avons passé en revue sur plus de 15 ans les résultats de prothèses totales du genou (PTG) avec préservation du ligament croisé chez des patients atteints de polyarthrite rhumatoïde. MÉTHODES: Nous avons examiné les dossiers et les radiographies des patients pour évaluer l'amplitude de mouvement et les contractures en flexion des genoux, le descellement des composants et l'ostéolyse à l'interface os­ciment. Notre paramètre principal était la révision d'un composant fémoral ou tibial, peu importe la raison, et le paramètre secondaire était la révision, peu importe la raison, ainsi que les fractures périprothétiques durant la période de suivi. RÉSULTANTS: Notre étude a regroupé 112 patients (7 hommes, 105 femmes; 176 genoux). L'âge moyen était de 49,3 ans (entre 33 et 64 ans). Vingt-et-un patients sont décédés et 16 ont été perdus au suivi, ce qui laissait 75 patients (119 genoux) et un suivi minimum de 15 ans (moyenne 16,1 ans) pour notre analyse. Parmi ces patients, 61 (101 genoux) étaient disponibles pour évaluation clinique et radiologique à la dernière évaluation de suivi. Sur une moyenne de 12,2 ans (entre 6 et 16 ans), une révision a été nécessaire chez 14 patients (19 genoux), y compris 1 patient porteur d'une infection. Onze patients (11 genoux) ont présenté des fractures périprothétiques en moyenne 11,4 ans (entre 5 et 14 ans) après l'intervention initiale. Le taux de survie, avec pour paramètre principal la révision d'un composant fémoral ou tibial, qu'elle qu'en soit la raison, a été de 98,7 % à 10 ans et de 83,6 % à 17 ans. Le taux de survie des révisions et de fractures périprothétiques a été de 97,6 % à 10 ans et de 76,9 % à 17 ans. CONCLUSION: Il faut porter une attention spéciale au descellement des composants ou à la fracture périprothétique après plus de 10 ans de suivi dans cette catégorie de patients.

Usefulness of the korean knee score for evaluation of the results of total knee arthroplasty.

PURPOSE: The Korean Knee score (KKS) was designed to reflect the floor-sitting lifestyle that necessitates high knee flexion. The purpose of this study is to assess whether the KKS reflects the floor-sitting lifestyle more accurately than the previously developed Knee Society clinical rating system. In addition, the presence of ceiling effects was compared between the two rating systems. MATERIALS AND METHODS: Eighty-one consecutive patients (120 knees) who were assessed regularly after total knee arthroplasty (TKA) on an outpatient basis between January 2012 and December 2012 were enrolled. All patients were asked to complete a questionnaire to assess the Knee Society Knee score (KSKS), Knee Society Function score (KSFS), and KKS. RESULTS: At the final follow-up, the mean KSKS, KSFS, and KKS were 91.2, 86.0, and 70.1, respectively, and the scores were similar between the ≥125° maximum flexion group and <125° maximum flexion group. However, the 'floor life' subdomain score of the KKS was significantly higher in the >125° maximum flexion group (15.13 vs. 11.24, p=0.001). The number of cases with the highest possible score was 24 (20%) for the KSKS and 47 (39%) for the KSFS, whereas none of the cases obtained the highest possible KKS. According to the standard deviation method, more substantial ceiling effects were present in the KSKS (83 cases, 69.1%) and KSFS (67 cases, 55.8%) than in the KKS (23 cases, 19.2%). CONCLUSIONS: Although, the KKS was effective in reducing the ceiling effect, it demonstrated limited improvement in assessing the ability to perform high knee flexion after TKA. However, the 'floor life' subdomain of KSS appeared to be valid for evaluating high flexion of the knee.

Risk factors of delirium in patients undergoing total knee arthroplasty.

Although postoperative delirium is a complicated disorder in elderly individuals, no study has been examined the risk factors associated with perioperative comorbidities and clinical laboratory data while specifically focusing on only total knee arthroplasty (TKA). In the present retrospective study, we aimed to evaluate the incidence and perioperative risk factors of postoperative delirium after TKA. Between April 2009 and May 2013, 287 patients (365 knees) aged >65 years who had undergone primary TKA were enrolled. These patients were assigned to the delirium group of 11 patients (11 knees) or the non-delirium group of 276 patients (354 knees). The incidence of delirium among the patients was 3.1% (11/365). Univariate logistic regression analysis indicated that a history of dementia, older age, lower body mass index (BMI) level, and a postoperative day 3 blood urea nitrogen (BUN) level of >14.9 mg/dL were risk factors. However, multivariate logistic regression analysis indicated that a history of dementia (adjusted odds ratio [AOR]: 10.4, [1.09, 100]), older age (AOR: 1.15, [1.01, 1.31]), and a postoperative day 3 BUN level of >14.9 mg/dL (AOR: 4.76, [1.15, 19.7]) were independent risk factors. Based on our findings, we believe that the surgeons should be careful to avoid the postoperative delirium and ensure the appropriate management for patients who have these risk factors.

The effect of a single dose of preemptive pregabalin administered with COX-2 inhibitor: a trial in total knee arthroplasty.

We sought to compare a group (Group L) (n=21) of patients that underwent total knee arthroplasty and received a single preoperative dose of pregabalin combined with a COX-2 inhibitor with a control group (Group C) (n=20) that only received a COX-2 inhibitor in terms of (1) acute postoperative pain intensity, (2) analgesic consumption, and (3) functional recovery. Mean cumulative fentanyl consumption during the first 48 hours was lower in Group L than in Group C (P<0.05). The pain scores at rest were lower in Group L at 6 and 12 hours after surgery (P<0.05). No significant intergroup difference was noted in functional recovery. The addition of pregabalin led to an additive reduction in early postoperative pain and analgesic consumption.

A randomized study to compare the efficacy and safety of extended-release and immediate-release tramadol HCl/acetaminophen in patients with acute pain following total knee replacement.

OBJECTIVE: To evaluate the relative efficacy and safety of extended-release tramadol HCl 75 mg/acetaminophen 650 mg (TA-ER) and immediate-release tramadol HCl 37.5 mg/acetaminophen 325 mg (TA-IR) for the treatment of moderate to severe acute pain following total knee replacement. METHODS: This phase III, double-blind, placebo-controlled, parallel-group study randomized 320 patients with moderate to severe pain (≥4 intensity on an 11 point numeric rating scale) following total knee replacement arthroplasty to receive oral TA-ER (every 12 hours) or TA-IR (every 6 hours) over a period of 48 hours. In the primary analysis, TA-ER was evaluated for efficacy non-inferior to that of TA-IR based on the sum of pain intensity difference (SPID) at 48 hours after the first dose of study drug (SPID48). Secondary endpoints included SPID at additional time points, total pain relief at all on-therapy time points (TOTPAR), sum of SPID and TOTPAR at all on-therapy time points (SPID + TOTPAR), use of rescue medication, subjective pain assessment (PGIC, Patient Global Impression of Change), and adverse events (AEs). RESULTS: Analysis of the primary efficacy endpoint (SPID48) could not establish the non-inferiority of TA-ER to TA-IR. However, a post hoc analysis with a re-defined non-inferiority margin did demonstrate the non-inferiority of TA-ER to TA-IR. No statistically significant difference in SPID at 6, 12, or 24 hours was observed between the TA-ER and TA-IR groups. Similarly, analysis of TOTPAR showed that there were no significant differences between groups at any on-therapy time point, and SPID + TOTPAR at 6 and 48 hours were similar among groups. There was no difference in the mean frequency or dosage of rescue medication required by both groups, and the majority of patients in both the TA-ER and TA-IR groups rated their pain improvement as 'much' or 'somewhat better'. The overall incidence of ≥1 AEs was similar among the TA-ER (88.8%) and TA-IR (89.5%) groups. The most commonly reported AEs by patients treated with TA-ER and TA-IR included nausea (49.7% vs 44.4%), vomiting (28.0% vs 24.2%), and decreased hemoglobin (23.6% vs 26.1%). This study is limited by the lack of placebo control, and the invalidity of the initial non-inferiority margin. CONCLUSION: This study demonstrated that the analgesic effect of TA-ER is non-inferior to TA-IR, and supports TA-ER as an effective and safe treatment for moderate to severe acute pain post total knee replacement. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, NCT01814878.

Posttraumatic stress disorder associated with orthopaedic trauma: a study in patients with extremity fractures.

OBJECTIVE: The aims of this prospective study were to determine the prevalence of posttraumatic stress disorder (PTSD) in a population of young male military conscripts who experienced an extremity long-bone fracture, and to evaluate whether injury-related variables are associated with the development of PTSD. DESIGN: Prospective, nonrandomized comparative study. SETTING: Level 1 trauma center. PATIENTS AND METHODS: A total of 148 men (age older than 18 years) who had 1 or more acute long-bone extremity fractures within 12 months and were seen at the Seoul Regional Military Manpower Center for examination of military conscripts from March 2013 to March 2014, were enrolled. The Korean version of the posttraumatic disorder scale was used to identify aspects of PTSD. The injury-related variables assessed included injury mechanism, fracture location and multiplicity, fracture severity, and the occurrence of joint ankylosis and secondary osteoarthritis. RESULTS: Of the 148 participants, 40 (27.0%) met the criteria for the diagnosis of PTSD. Multivariate logistic linear analysis confirmed that lower extremity fracture, multiple fractures, and a higher pain visual analog scale score were significantly (P = 0.042, P = 0.043 and P < 0.001, respectively) related to the occurrence of PTSD. CONCLUSIONS: Lower extremity fracture, multiple extremity fractures, and higher pain visual analog scale scores were significantly related to the occurrence of PTSD. To achieve an optimal recovery after orthopaedic injury, clinicians must address both physical and psychologic needs of their patients. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.