The influence of radiologic bone transparency after hybrid total knee arthroplasty on clinical outcomes: Minimum 6-year follow up of 214 cases.

BACKGROUND: This study aimed to investigate how bone transparency affects loosening of the cementless femoral component by serially analyzing radiologic images in hybrid total knee arthroplasty (TKA). METHODS: A total of 214 cases of TKA performed using the hybrid technique that were followed up for at least 6 years were retrospectively investigated. Bone transparency around the femoral component during the follow up period was evaluated. All TKA cases were divided into two groups and compared: those with radiologic bone transparency (bone transparency group, n = 51) and those without radiologic bone transparency (no bone transparency group, n = 163). RESULTS: The incidence of revision TKA in all patients was 6.1%, and obesity, preoperative and postoperative mechanical alignment did not affect surgical outcomes. All bone transparency cases were asymptomatic, and only 8/51 cases (15.7%) of bone transparency spontaneously resolved. Between the bone transparency and no bone transparency groups, there was no difference found in the preoperative and postoperative radiologic parameters and clinical outcomes. During the follow up period, there were four (1.9%) cases with a definite radiolucent line in the femoral component, all of which belonged to the bone transparency group. CONCLUSIONS: The bone transparency around the femoral component that appears on radiography after hybrid TKA could be an early sign of aseptic loosening; therefore, follow up serial radiography is essential.

Effectiveness of ERAS (Enhanced Recovery after Surgery) Protocol via Peripheral Nerve Block for Total Knee Arthroplasty.

Peripheral nerve block (PNB) for patients with total knee arthroplasty (TKA) is one of the recommended interventions in ERAS protocols. However, most existing studies involved unilateral TKA (UTKA). As such, this study aimed to evaluate the effectiveness of PNB in terms of immediate postoperative analgesia, length of hospital stays (LOS), and early functional outcomes in both UTKA and simultaneous bilateral TKAs (BTKAs). We reviewed 236 patients who underwent primary TKA with PNB, with 138 and 98 being UTKA and BTKAs, respectively; those in the PNB group underwent femoral nerve and adductor canal block. The matched control and PNB groups-who received intravenous/epidural patient-controlled analgesia (IVPCA/PCEA) alone or IVPCA in addition to PNB after surgery, respectively-were compared. The VAS scores at rest until 48 h after surgery were significantly lower in PNB groups compared to those in the IVPCA groups. At 0- 6 h of activity, VAS scores of the UTKA with PNB group were also lower than the IVPCA group. Compared to PCEA groups, VAS scores at 0-6 h of activity were higher in both the UTKA and BTKAs with PNB groups. However, at 24-48 h at rest, the scores of those in the UTKA with PNB group were lower than those in the PCEA group. The control and experimental UTKA and BTKAs groups had similar LOS and functional outcomes at 90 days postoperatively. In primary TKA, PNB has great analgesic effects for immediate postoperative pain control, and represents a similar analgesic effect to epidural PCA.

Difference between medial and lateral tibia plateau in the coronal plane: importance of preoperative evaluation for medial unicompartmental knee arthroplasty.

BACKGROUND: Setting bone cutting levels for different joint line orientations of the medial and lateral tibia plateaus in individual patients is not clear. We aimed to evaluate the difference between joint line orientation of the medial and lateral tibia plateaus relative to the horizontal line of mechanical axis of tibia as tibial plateau difference (TPD) for an optimal tibial bone cut in medial unicompartmental knee arthroplasty (UKA) and determine which factors could influence TPD. We aimed to investigate the effect of preoperative TPD on polyethylene liner size in medial UKA. METHODS: TPD in the coronal plane were measured in 181 female patients (181 knees). To determine the morphology of proximal tibia according to the severity of osteoarthritis, the patients were classified into three groups based on diagnosis and treatment: 80 who underwent robot-assisted medial UKA, 45 who underwent total knee arthroplasty (TKA), and 56 with early-stage osteoarthritis (OA) who had conservative management. Also, we divided the medial UKA group into two groups according to TPD (greater than or less than 5 mm) and compared polyethylene liner sizes. RESULTS: No significant difference was observed in TPD (p = 0.662), difference between the medial and lateral femoral condyle levels (p = 0.54), medial proximal tibial angle (p = 0.169), or posterior tibial slope (p = 0.466) among the three groups. Increased TPD was significantly associated with increased mechanical femorotibial angle(mFTA) (p < 0.01). The medial UKA group was divided into two groups according to TPD greater or less than 5 mm. Thicker polyethylene liners were used for groups with TPD greater than 5 mm (8.5 ± 0.7 mm versus 8.2 ± 0.3 mm, p = 0.01). Additionally, the proportion of patients using the thinnest polyethylene (8 mm) in each TPD group (greater or less than 5 mm) was higher in patients with TPD less than 5 mm (82.4% versus 58.7%, p = 0.038). CONCLUSIONS: Preoperative measurement of TPD is important to help surgeons predict the most appropriate bone cutting level in the coronal plane in primary medial UKA. Tibial bone resection would be likely to be thicker than needed in patients with increased TPD in medial UKA.

Acetabular labral tear is associated with high pelvic incidence with or without femoroacetabular impingement morphology.

PURPOSE: The aim of this study was to investigate the association between pelvic sagittal parameters and acetabular labral tears. METHODS: Three-hundred and sixty-five patients (449 hips) who underwent magnetic resonance imaging (MRI) or magnetic resonance arthrogram (MRA) for hip pain were enrolled in this study. Pelvic sagittal parameters, including the pelvic incidence, pelvic tilt, and sacral slope, were measured with a standing lumbosacral lateral radiograph. All subjects were divided into two groups according to the presence or absence of radiologic acetabular labral tears and compared. Furthermore, the two groups were divided into subgroups according to whether femoroacetabular impingement (FAI) morphology was present or not and compared. RESULTS: Pelvic incidence was greater in the labral tear group than in the non-labral tear group (52.3° ± 8.2° versus 47.1° ± 6.8°, p < 0.001). After accounting for potentially confounding variables, we found that higher age (odds ratio 1.04, 95% confidence interval [CI] 1.02 to 1.06, p = 0.001), FAI (odds ratio 15.11, 95% CI 7.43 to 30.75, p < 0.001), and high pelvic incidence (odds ratio 1.13, 95% CI 1.09 to 1.17, p < 0.001) were independently associated with acetabular labral tear. When only the patients without FAI (308 hips) were divided into groups with and without acetabular labral tear, we found that higher age (odds ratio 1.03, 95% CI 1.01 to 1.06, p = 0.008) and high pelvic incidence (odds ratio 1.15, 95% CI 1.11 to 1.19, p < 0.001) were independently associated with acetabular labral tear. CONCLUSION: Acetabular labral tear is associated with high pelvic incidence with or without FAI morphology. LEVEL OF EVIDENCE: III.

Accuracy of 2D CT-Based Measurements of Rotational Alignment of the Femoral Component for Total Knee Arthroplasty.

PURPOSE: We aimed to investigate the accuracy of two-dimensional computed tomography (2D-CT)-based methods for measuring rotational alignment of the femoral component during total knee arthroplasty in comparison to reference values for three-dimensional (3D) reconstruction. MATERIALS AND METHODS: We selected the "most protruding transepicondylar axis section," "most protruding posterior condylar line section," and "distal femoral cut section" on 2D-CT images for 100 knees. We investigated posterior condylar angle (PCA) and condylar twist angle (CTA) values using three different methods on 2D-CT and compared to these values to those obtained using a 3D model. RESULTS: The mean PCA and CTA values were 2.8° and 7.0° on the 3D model and 2.0° to 2.1° and 5.9° to 6.0° on 2D-CT, respectively. Errors in PCA and CTA measurement included internal rotation of 0.8° and 1.1° with the 1-plane and 2-plane methods and 0.9° and 1.0° with the assumed resection method, respectively. CONCLUSION: Mean errors in PCA and CTA values measured using three different methods on 2D-CT were not significantly different. However, PCA and CTA values measured on 2D-CT were approximately 1° smaller than their 3D values. Thus, we suggest that adding 1° to the mean PCA and CTA values obtained from a single plane of 2D-CT would provide values similar to those obtained from 3D reconstruction.

Cross-Sectional Association between Hypercholesterolemia and Knee Pain in the Elderly with Radiographic Knee Osteoarthritis: Data from the Korean National Health and Nutritional Examination Survey.

Few studies have reported the relationship between knee pain and hypercholesterolemia in the elderly population with osteoarthritis (OA), independent of other variables. The aim of this study was to reveal the association between knee pain and metabolic diseases including hypercholesterolemia using a large-scale cohort. A cross-sectional study was conducted using data from the Korea National Health and the Nutrition Examination Survey (KNHANES-V, VI-1; 2010-2013). Among the subjects aged ≥60 years, 7438 subjects (weighted number estimate = 35,524,307) who replied knee pain item and performed the simple radiographs of knee were enrolled. Using multivariable ordinal logistic regression analysis, variables affecting knee pain were identified, and the odds ratio (OR) was calculated. Of the 35,524,307 subjects, 10,630,836 (29.9%) subjects experienced knee pain. Overall, 20,290,421 subjects (56.3%) had radiographic OA, and 8,119,372 (40.0%) of them complained of knee pain. Multivariable ordinal logistic regression analysis showed that among the metabolic diseases, only hypercholesterolemia was positively correlated with knee pain in the OA group (OR 1.24; 95% Confidence Interval 1.02-1.52, p = 0.033). There were no metabolic diseases correlated with knee pain in the non-OA group. This large-scale study revealed that in the elderly, hypercholesterolemia was positively associated with knee pain independent of body mass index and other metabolic diseases in the OA group, but not in the non-OA group. These results will help in understanding the nature of arthritic pain, and may support the need for exploring the longitudinal associations.

The effect of hamstring tightness on intraoperative extension gap in posterior stabilized total knee arthroplasty.

This study aimed to determine the factors related to intraoperative extension gap (EG) in patients who underwent posterior-stabilized total knee arthroplasty (TKA). A total of 106 TKAs in 84 patients were retrospectively reviewed. Only patients who underwent the same method of bone resection were included consecutively. Bilateral popliteal angle (BPA) was used as an indicator of hamstring tightness. EG and extension space angle were measured using an offset type tensor. The associations between patient variables and EG were analyzed using multivariable linear regression and Pearson's correlation coefficients. The average EG was 12.9 ± 2.1 mm, and the average extension space angle was 2.8° ± 3.2°. BPA was greater than flexion contracture in most cases (94.3%), and no difference was found in only six cases (5.7%). According to multivariable linear regression analysis which was conducted after modifying the BPA into a categorical variable by 5°, EG was correlated with BPA (p < 0.001). Pearson's correlation coefficient between EG and BPA was - 0.674 (p < 0.001). No other factors were significantly correlated with intraoperative EG. The present study found that popliteal angle is a different entity from flexion contracture, and that it is a predictable factor for EG in osteoarthritis patients. Smaller BPAs led to larger EG in patients who underwent the same degree of bone resection.

Anatomical tibial component is related to more medial tibial stress shielding after total knee arthroplasty in Korean patients.

PURPOSE: This study aimed to investigate stress shielding of anatomical tibial components (ATCs) in comparison to conventional symmetric tibial components (STCs) in Korean patients which may be related to medial tibial bone loss. METHOD: 78 knees in 59 patients with ATCs (Persona™) and 74 knees in 58 patients with STCs (NexGen LPS-Flex™) were retrospectively reviewed. Radiographic parameters and clinical outcomes in both groups were compared. Logistic regression analysis was performed to identify risk factors for medial tibial bone loss. RESULTS: Medial tibial bone loss was significantly greater in the ATC group (1.6 ± 1.3 mm) than in the STC group (0.4 ± 0.8 mm) (p < 0.001). The ATC group showed a shorter distance between the distal metal tip and anteromedial cortex and higher invading into the sclerotic bone lesion (ISBL) than the STC group (p = 0.034 and p = 0.044, respectively). Multiple logistic regression analysis suggested ATC, a shorter distance to the anteromedial cortex, and the presence of ISBL as risk factors for medial tibial bone loss. The odds ratios of medial tibial bone loss according to type of prosthesis, distance to anteromedial cortex, and presence of ISBL were 6.25 (range 2.86-13.63, p < 0.001), 0.69 (range 0.51-0.93, p = 0.015), and 3.79 (range 1.56-9.21, p = 0.003), respectively. Notwithstanding, there was no difference in clinical outcomes between the two groups. CONCLUSION: In Korean patients, ATCs potentially causes greater medial tibial bone loss due to stress shielding than STCs. The design, however, does not yet appear to affect clinical outcomes at mid-term follow-up. LEVEL OF EVIDENCE: Retrospective cohort study, level III.

Anthropometric Measurement About the Safe Zone for Transacetabular Screw Placement in Total Hip Arthroplasty in Asian Middle-Aged Women: In Vivo Three-Dimensional Model Analysis.

BACKGROUND: Although the pelvic vascular injury caused by a transacetabular screw is rare, it is a major local complication of total hip arthroplasty. We aimed to obtain anthropometric data about the safe zone for the placement of transacetabular screws by analyzing the three-dimensional (3D) reconstruction model and determine the safe length of transacetabular screws by performing the 3D simulated surgery. METHODS: We reviewed 50 hips of 25 patients who underwent lower extremity angiographic computed tomography scans retrospectively. We reconstructed the 3D models of 50 hips with normal pelvic bone and vascular status using the customized computer software. We measured the central angle and safe depth of the safe zone of the transacetabular screws on the 3D models. We also performed the 3D simulated surgery to confirm the safe length of screws in each hole of the customized cup implant. RESULTS: The measured central angle of the posterior-superior area was 79.5°. And we determined a mean safe depth of 49.8 mm in the safe zone, with a central angle of 47.7°. During the 3D simulated surgery, we determined a mean safe length of the transacetabular screw of 43.3 mm when applied to a lateral hole on a line bisecting the posterior-superior area. CONCLUSION: Although our study was limited by the use of a virtual computer program, the quantitative measurements obtained can help reduce the incidence of pelvic vascular injury during transacetabular screw fixation in total hip arthroplasty.

Preoperative Carbohydrate Drinks Do Not Decrease Postoperative Nausea and Vomiting in Type 2 Diabetic Patients Undergoing Total Knee Arthroplasty-A Randomized Controlled Trial.

INTRODUCTION: We evaluated whether preoperative carbohydrate drink would be able to decrease postoperative nausea and vomiting (PONV) and improve the quality of recovery (QoR) in diabetic patients undergoing total knee arthroplasty (TKA). METHODS: Eighty-two patients were randomized to either the intravenous (IV) Dextrose group (n = 41) or Oral carbohydrate (CHO) group (n = 41). The IV Dextrose group received dextrose solution mixed with insulin while fasting, and the Oral CHO group received carbohydrate drinks preoperatively. PONV was assessed up to postoperative 36 hours, and QoR was assessed before surgery and on postoperative day (POD) 1. Blood glucose was measured from the morning of surgery until POD 1. RESULTS: PONV scores were not different between the groups. Postoperative QoR scores were significantly higher in the Oral CHO group (median [interquartile range]; 160 [153 to 167]) than the IV Dextrose group (155 [147 to 159]) (P = 0.009), but the difference did not meet the minimal clinically important difference. Blood glucose was comparable between the groups. DISCUSSION: Preoperative CHO drink did not reduce PONV in diabetic patients after total knee arthroplasty. A statistically significant but clinically questionable improvement in the QoR was seen in the Oral CHO group. However, preoperative CHO drink did not increase hyperglycemia, which suggests that it may be a safe component of perioperative care in diabetic patients.

High Pelvic Incidence Is Associated with Disease Progression in Nontraumatic Osteonecrosis of the Femoral Head.

BACKGROUND: Although several factors exacerbate osteonecrosis of the femoral head (ONFH), little is known about whether pelvic sagittal parameters are associated with a greater risk of ONFH progression. QUESTIONS/PURPOSES: The purpose of this study was to investigate the association between pelvic sagittal parameters and disease progression (collapse of the femoral head) in patients with nontraumatic ONFH. METHODS: From March 2010 through December 2016, we saw 401 patients with unilateral ONFH diagnosed at an outpatient clinic using plain radiography and MRI that were retrospectively reviewed. Of those, 276 patients met our inclusion criteria: Association Research Circulation Osseous (ARCO) Stage I or II nontraumatic unilateral ONFH without femoral head collapse, older than 18 years, and no prior surgical treatment. In all, 74% (203 of 276) of hips had complete follow-up (clinical and radiographic) at a minimum of 2 years. The pelvic sagittal parameters (pelvic incidence, pelvic tilt, and sacral slope) of all patients were measured with standing radiographs by two observers. Progression of disease and potential collapse of the femoral head of all patients (ARCO Stage ≥ III) was examined using radiography every 2 to 3 months after the first outpatient clinic visit. If patients with intractable pain associated with collapse of the femoral head did not respond to nonoperative treatment, THA was performed during the follow-up period. The patients were divided into two groups for comparison: those whose femoral head collapsed within 12 months (rapid progression group) and those whose femoral head did not collapse (nonrapid progression group). The rapid progression group consisted of 49 men and 55 women with a mean age of 55 years; the nonrapid progression group consisted of 60 men and 39 women with a mean age of 56 years. Factors such as age, sex, BMI, size of necrotic lesions, location of necrosis, necrosis risk factor associated with the rapid progression of disease were analyzed using an exploratory univariate analysis followed by a multivariate analysis. RESULTS: Pelvic incidence (53° ± 9° versus 49° ± 7°; p < 0.01) and sacral slope (38° ± 9° versus 33° ± 7°; p < 0.01) were greater in the rapid progression group than in the non-rapid progression group. After accounting for potentially confounding variables like age, sex, BMI, size of necrotic lesions, location of necrosis, and necrosis risk factors, the only variable we found that was independently associated with more rapid disease progression was high (> 55°) pelvic incidence (odds ratio, 0.95 [95% CI 0.91 to 0.99]; p = 0.03). CONCLUSIONS: After controlling for potential confounders such as age, sex, BMI, size of necrotic lesions, location of necrosis, and necrosis risk factors, we found that a high pelvic incidence was associated with a greater likelihood of femoral head collapse in patients with nontraumatic ONFH. Assessing pelvic sagittal parameters in patients with early nontraumatic ONFH may help anticipate which patients are at risk for femoral head collapse, but future prospective studies are needed to confirm these findings. LEVEL OF EVIDENCE: Level III, therapeutic study.

Being Underweight Is Associated with Worse Surgical Outcomes of Total Knee Arthroplasty Compared to Normal Body Mass Index in Elderly Patients.

PURPOSE: Being underweight has never been studied in relation to the radiologic and clinical outcomes of total knee arthroplasty (TKA) in elderly patients. The aim of this study was to determine the effect of being underweight on TKA radiological and clinical outcomes and to investigate whether being underweight influences postoperative complications compared to normal body mass index (BMI) in elderly patients. PATIENTS AND METHODS: A total of 118 female patients aged 65 years or older with BMI < 25 kg/m2 who underwent primary TKA were divided into two groups based on BMI: group A: 18.5 kg/m2 < BMI < 25 kg/m2; group B: BMI < 18.5 kg/m2. The radiologic and clinical outcomes were evaluated at follow-up of 6, 12, and 24 months after surgery such as the hip-knee-ankle angle, the American Knee Society (AKS) score, Western Ontario and McMaster University score (WOMAC), and patellofemoral (PF) scale. Moreover, postoperative complications during follow-up were investigated. RESULTS: Preoperative clinical scores did not differ significantly between the two groups. Postoperative WOMAC pain (1.8 ± 1.9 versus 3.4 ± 2.6, p = 0.02), WOMAC function (12.4 ± 8.1 versus 16.5 ± 8.5, p = 0.012) and PF scales (26.1 ± 3.6 versus 23.7 ± 4.1, p = 0.002) were worse in the underweight group at 12 and 24 months after surgery. The frequency of postoperative complications did not differ significantly between groups. In multivariate linear regression analysis, underweight patient group was significantly associated with worse postoperative WOMAC and PF scores (p = 0.002, 0.005). CONCLUSION: Although postoperative complications of TKA did not differ between groups, underweight patients had worse clinical outcomes of TKA compared to patients with normal BMI in elderly patients. Therefore, care should be taken when performing TKA in elderly underweight patients.

Cigarette smoking and knee osteoarthritis in the elderly: Data from the Korean National Health and Nutritional Examination Survey.

BACKGROUND: The relationship between smoking and osteoarthritis (OA) has not been investigated in a large-scale study. The aim of this study was to examine the relationship between smoking and knee OA in the elderly. METHODS: This study included 5117 subjects aged >60 years who responded to questionnaires on their history of smoking and knee OA diagnosed by a physician taken from the Korean National Health and Nutritional Examination Survey (KNHANES-VI) 2013-2015. We classified all 5117 subjects into 2 groups (the OA group and non-OA group) and compared the demographics and characteristics between the 2 groups. A multivariate logistic regression analysis was conducted to investigate the possible association between knee OA and smoking. RESULTS: The prevalence of current smoking in the OA group (5.1%) was significantly lower than in the non-OA group (14.6%; p < 0.001). Furthermore, the proportion of moderate smokers who smoked >10 cigarettes per day or heavy smokers who smoked >20 cigarettes per day was significantly higher in the non-OA group. In the multivariate analysis, current smoking history was a preventative factor for the prevalence of OA in a multivariate model that included age, sex, body mass index, waist circumference (OR: 0.752, 95% CI: 0.571-0.989, p = 0.042). CONCLUSIONS: This large-scale national study highlights an inverse association between smoking and the prevalence of knee OA in the general Korean elder adult population, primarily in males. Further investigation of this relationship between smoking and knee OA is needed to determine smoking's specific mechanism of protection against knee OA.

Robot-assisted unicompartmental knee arthroplasty can reduce radiologic outliers compared to conventional techniques.

BACKGROUND: The aim of this study was to compare the clinical and radiologic outcomes of robot-assisted unicompartmental knee arthroplasty (UKA) to those of conventional UKA in Asian patients. METHODS: Fifty-five patients underwent robot-assisted UKA and 57 patients underwent conventional UKA were assessed in this study. Preoperative and postoperative range of motion (ROM), American Knee Society (AKS) score, Western Ontario McMaster University Osteoarthritis Index scale score (WOMAC), and patellofemoral (PF) score values were compared between the two groups. The mechanical femorotibial angle (mFTA) and Kennedy zone were also measured. Coronal alignments of the femoral and tibial components and posterior slopes of the tibial component were compared. Additionally, polyethylene (PE) liner thicknesses were compared. RESULTS: There was no significant difference between the two groups regarding postoperative ROM, AKS, WOMAC and PF score. Robot group showed fewer radiologic outliers in terms of mFTA and coronal alignment of tibial and femoral components (p = 0.022, 0.037, 0.003). The two groups showed significantly different PE liner thicknesses (8.4 ± 0.8 versus 8.8 ± 0.9, p = 0.035). Robot group was the only influencing factor for reducing radiologic outlier (postoperative mFTA) in multivariate model (odds ratio: 2.833, p = 0.037). CONCLUSION: In this study, robot-assisted UKA had many advantages over conventional UKA, such as its ability to achieve precise implant insertion and reduce radiologic outliers. Although the clinical outcomes of robot-assisted UKA over a short-term follow-up period were not significantly different compared to those of conventional UKA, longer follow-up period is needed to determine whether the improved radiologic accuracy of the components in robotic-assisted UKA will lead to better clinical outcomes and improved long-term survival.

Impact of Renal Function on the Surgical Outcomes of Displaced Femoral Neck Fracture in Elderly Patients.

BACKGROUND: The aim of this study was to investigate the relationship between estimated glomerular filtration rate (eGFR) and outcomes of bipolar hemiarthroplasty for femoral neck fracture in elderly patients, and to compare postoperative complications and mortality among groups according to eGFR. METHODS: A total of 181 patients who underwent bipolar hemiarthroplasty for displaced femoral neck fracture were divided into three groups according to eGFR. Data were retrospectively analyzed. Group 1 had 96 patients with eGFR greater than or equal to 60 mL/min/1.73 m2; Group 2 had 54 patients with eGFR greater than or equal to 30 mL/min/1.73 m2 and lower than 60 mL/min/1.73 m2; and Group 3 had 31 patients with eGFR lower than 30 mL/min/1.73 m2. Postoperative complications and mortality were compared between groups at a minimum 2-year follow-up. RESULTS: Patients in Group 3 had the longest hospital stay of the three groups (p = 0.001). The rates of medical complications did not differ significantly among groups. However, Group 2 and 3 had higher rates of surgical complications (p = 0.001) and mortality (p = 0.043) than Group 1. Severe renal impairment was associated with increased risk of postoperative complications compared to mild renal impairment (odds ratio (95% confidence interval) = 4.33 (1.32-13.19), p = 0.015). CONCLUSION: Patients with moderate or severe decreased eGFR associated with chronic kidney disease (CKD) could have higher postoperative complications and mortality after bipolar hemiarthroplasty compared to patients with CKD stage 1 or 2.

Regulation of MMP and TIMP expression in synovial fibroblasts from knee osteoarthritis with flexion contracture using adenovirus-mediated relaxin gene therapy.

PURPOSE: The aim of this study was to investigate the effects of relaxin (RLN) expression on fibrosis inhibition in synovial fibroblasts. MATERIALS AND METHODS: Tissue cells from patients with knee osteoarthritis and >30° flexion contractures were utilised. Synovial fibroblasts were activated by TGF-ß1 (two nanograms per millilitre) and then exposed to Ad-RLN as a therapeutic gene, adenovirus-lacZ construct as a marker gene, and SB505124 as an inhibitor for TGF-ß1 signal for 48 h. The mRNA expression levels of collagens and MMPs were analysed by reverse transcription-polymerase chain reaction. Also, fibronectin, phosphorylation of Smad2 and ERK1/2, alpha smooth muscle actin, TIMP-1, TIMP-2, MMP-1 and MMP-13 levels were estimated using western blotting, and the total collagen synthesis was assayed. RESULTS: Ad-RLN-transduced synovial fibroblasts demonstrated 17%, 13%, and 48% reduction in collagen I, III and IV mRNA expression levels, respectively, and a 40% decrease in MMP-3, MMP-8, 20% decrease in MMP-9, MMP-13 mRNA expression, compared to non-Ad-RLN-transduced cells. In protein expression, Ad-RLN-transduced synovial fibroblasts demonstrated 46% increase in MMP-1, 5% decrease in MMP-2, 51% increase in MMP-9, and 22% increase in MMP-13, compared to non-Ad-RLN-transduced cells. Ad-RLN-transduced synovial fibroblasts showed a 25% decrease in TIMP-1 and 65% decrease in TIMP-2 protein expression at 48h, compared to non-Ad-RLN-transduced cells. Ad-RLN-transduced synovial fibroblasts demonstrated a 45% inhibition of fibronectin in protein expression level and 38% decrease in total collagen synthesis at 48h, compared to non-Ad-RLN-transduced cells. CONCLUSION: Relaxin expression exerted anti-fibrogenic effects on synovial fibroblasts from patients with knee osteoarthritis and flexion contractures. Therefore, relaxin could be an alternative therapeutic agent during the initial stage of osteoarthritis with flexion contracture by exerting its anti-fibrogenic effects.

Reliability of Intraoperative Knee Range of Motion Measurements by Goniometer Compared with Robot-Assisted Arthroplasty.

Accurate measurement of knee range of motion (ROM) is critical to predict the outcomes of knee surgery and prognosis. We investigated the reliability of knee ROM measurements by goniometer compared with robotic system. Fifty-three patients with medial osteoarthritis who were planning to undergo unicompartmental knee arthroplasty (UKA) with robotic UKA were prospectively enrolled. During the operation, knee ROM measurement was performed in both flexion and extension before and after insertion of the implant using both a goniometer and robotic system. The intraclass correlation coefficient (ICC) of extension measured by the goniometer and robotic system showed good agreement; however, the ICC of flexion did not show good agreement. During passive flexion, the mean values measured before insertion of the implant were significantly lower by goniometer (134.6 ± 6.43) than by robot (145.4 ± 6.80; p = 0.017); likewise, the mean values after insertion of the implant were significantly lower by goniometer (138.6 ± 6.07) than by robotic system (147.0 ± 6.60; p = 0.045). A goniometer can underestimate knee ROM measurements compared with robotic system, especially in flexion. Orthopaedic surgeons should be cautious when measuring the flexion angle with a goniometer.

Utility of False Profile View for Screening of Ischiofemoral Impingement.

PURPOSE: Ischiofemoral impingement (IFI)-primarily diagnosed by magnetic resonance imaging (MRI)-is an easily overlooked disease due to its low incidence. The purpose of this study was to evaluate the usefulness of false profile view as a screening test for IFI. MATERIALS AND METHODS: Fifty-eight patients diagnosed with IFI between June 2013 and July 2017 were enrolled in this retrospective study. A control group (n=58) with matching propensity scores (age, gender, and body mass index) were also included. Ischiofemoral space (IFS) was measured as the shortest distance between the lateral cortex of the ischium and the medial cortex of lesser trochanter in weight bearing hip anteroposterior (AP) view and false profile view. MRI was used to measure IFS and quadratus femoris space (QFS). The receiver operating characteristics (ROC), area under the ROC curve (AUC) and cutoff point of the IFS were measured by false profile images, and the correlation between the IFS and QFS was analyzed using the MRI scans. RESULTS: In the false profile view and hip AP view, patients with IFI had significantly decreased IFS (P<0.01). In the false profile view, ROC AUC (0.967) was higher than in the hip AP view (0.841). Cutoff value for differential diagnosis of IFI in the false profile view was 10.3 mm (sensitivity, 88.2%; specificity, 88.4%). IFS correlated with IFS (r=0.744) QFS (0.740) in MRI and IFS (0.621) in hip AP view (P<0.01). CONCLUSION: IFS on false profile view can be used as a screening tool for potential IFI.

Does Simultaneous Computed Tomography and Quantitative Computed Tomography Show Better Prescription Rate than Dual-energy X-ray Absorptiometry for Osteoporotic Hip Fracture?

PURPOSE: This study aimed to evaluate the efficacy of simultaneous computed tomography (CT) and quantitative CT (QCT) in patients with osteoporotic hip fracture (OHF) by analyzing the osteoporosis detection rate and physician prescription rate in comparison with those of conventional dual-energy X-ray absorptiometry (DXA). MATERIALS AND METHODS: This study included consecutive patients older than 65 years who underwent internal fixation or hip arthroplasty for OHF between February and May 2015. The patients were assigned to either the QCT (47 patients) or DXA group (51 patients). The patients in the QCT group underwent QCT with hip CT, whereas those in the DXA group underwent DXA after surgery, before discharge, or in the outpatient clinic. In both groups, the patients received osteoporosis medication according to their QCT or DXA results. The osteoporosis evaluation rate and prescription rate were determined at discharge, postoperative (PO) day 2, PO day 6, and PO week 12 during an outpatient clinic visit. RESULTS: The osteoporosis evaluation rate at PO week 12 was 70.6% (36 of 51 patients) in the DXA group and 100% in the QCT group (P<0.01). The prescription rates of osteoporosis medication at discharge were 70.2% and 29.4% (P<0.001) and the cumulative prescription rates at PO week 12 were 87.2% and 60.8% (P=0.003) in the QCT and DXA groups, respectively. CONCLUSION: Simultaneous CT and QCT significantly increased the evaluation and prescription rates in patients with OHF and may enable appropriate and consistent prescription of osteoporosis medication, which may eventually lead to patients' medication compliance.

How Long Does Antimycobacterial Antibiotic-loaded Bone Cement Have In Vitro Activity for Musculoskeletal Tuberculosis?

BACKGROUND: Antibiotic-loaded bone cement is accepted as an effective treatment modality for musculoskeletal tuberculosis. However, comparative information regarding combinations and concentrations of second-line antimycobacterial drugs, such as streptomycin and amoxicillin and clavulanic acid, are lacking. QUESTIONS/PURPOSES: (1) In antibiotic-loaded cement, is there effective elution of streptomycin and Augmentin® (amoxicillin and clavulanic acid) individually and in combination? (2) What is the antibacterial activity duration for streptomycin- and amoxicillin and clavulanic acid -loaded cement? METHODS: Six different types of bone cement discs were created by mixing 40 g bone cement with 1 or 2 g streptomycin only, 0.6 g or 1.2 g Augmentin® (amoxicillin and clavulanic acid) only, and a combination of 1 g streptomycin plus 0.6 g amoxicillin and clavulanic acid and 2 g streptomycin plus 1.2 g amoxicillin and clavulanic acid. Five bone discs of each type were incubated in phosphate buffered saline for 30 days with renewal of the phosphate buffered saline every day. The quantity of streptomycin and/or amoxicillin and clavulanic acid in eluates were measured by a liquid chromatography-mass spectrometry system, and the antimycobacterial activity of eluates against Mycobacterium tuberculosis H37Rv, were calculated by comparing the minimal inhibitory concentration of each eluate with that of tested drugs using broth dilution assay on microplate. RESULTS: Streptomycin was detected in eluates for 30 days (in 1 g and 2 g discs), whereas 1.2 g amoxicillin and clavulanate eluted until Day 7 and 0.6 g amoxicillin and clavulanate until Day 3. All eluates in streptomycin-containing discs (streptomycin only, and in combination with amoxicillin and clavulanic acid) had effective antimycobacterial activity for 30 days, while amoxicillin and clavulanate-only preparations were only active until Day 14. The antimycobacterial activity of eluates of 2 g streptomycin plus 1.2 g amoxicillin and clavulanate were higher than those of discs containing 1 g streptomycin plus 0.6 g amoxicillin and clavulanate until Day 3, without differences (Day 3, 1 g streptomycin plus 0.6 g amoxicillin and clavulanate: 17.5 ± 6.85 ug/mL; 2 g streptomycin plus 1.2 g amoxicillin and clavulanate: 32.5 ± 16.77 ug/mL; p = 0.109). After Day 7, however, values of the two combinations remained no different than that of Day 30 (Day 30, 1 g streptomycin plus 0.6 g amoxicillin and clavulanate: 0.88 ± 0.34 ug/mL; 2 g streptomycin plus 1.2 g amoxicillin and clavulanate: 0.59 ± 0.94 ug/mL; p = 0.107). CONCLUSIONS: Streptomycin, in the form of antibiotic-loaded bone cement, had effective elution characteristics and antimycobacterial effects during a 30-day period, whereas amoxicillin and clavulanate only had effective elution and antimycobacterial characteristics during the early period of this study. The two drugs did not interfere with each other during the elution test. CLINICAL RELEVANCE: This research revealed that combinations of streptomycin and amoxicillin and clavulanate mixed with bone cement are effective for 30 days. Further trials to determine various different combinations of drugs are necessary to improve the effectiveness of treatments for musculoskeletal tuberculosis.