Risk factors affecting hip fracture patterns in an elderly Korean patient population.

Hip fracture in the elderly patient population, particularly the Korean patient cohort, is one of the most serious complications of osteoporosis and currently increasing alongside age. In this study, we attempted to identify various factors that could either indicate the risk for an intertrochanteric or femoral neck fracture in an osteoporotic Korean hip fracture patient cohort ≥ 65 years old. A retrospective analysis of 168 patients was performed for those who underwent surgical treatment for either an intertrochanteric or femoral neck fracture at Daegu Catholic University Medical Center from January 2013 to December 2015. Inclusion criteria included patients who sustained a intertrochanteric or femoral neck fracture between the designated time frame, ≥65 years old, and of Korean ethnicity. Differences between the T-score and Z-score regarding bone mineral density (BMD) and the relationship between BMD and subtype of the fracture for the intertrochanteric (n = 92) and femoral neck fracture (n = 76) groups were obtained. Demographical factors (age, sex, weight, height, and body mass index [BMI]) were analyzed as potential risk factors for intertrochanteric or femoral neck fractures using software. Of the total 168 patients, mean weight and BMI values were found to be lower in the intertrochanteric fracture group (P = .033) compared to the femoral neck fracture group (P = .044). Additionally, Z-scores for the intertrochanteric fracture group were lower in the trochanter (P = .030), intertrochanteric (P = .029), and Ward's triangle (P = .029) regions. Regarding the intertrochanteric fracture group, the A3 subgroup showed lower T-scores of the trochanteric region than the A1 fracture subgroup (P = .010). In an elderly Korean hip patient cohort, lower body weight, BMI, and BMD Z-scores are correlated with a higher incidence of intertrochanteric fractures when compared to femoral neck hip fractures.

Efficacy of skin preparation solutions in patients with total knee replacement: A randomized controlled trial.

PURPOSE: Surgical site infection following total knee replacement is considered as one of the most severe postoperative complications. The presence of bacteria at the surgical site is the most important risk factor and therefore it is essential to prevent infection through appropriate preoperative skin preparation. The purpose of this study was to examine the presence and type of native bacteria on the incision site and to assess which skin preparation is most effective to sterilize those native bacteria. METHODS: Scrub-and-paint 2 step method was used for standard preoperative skin preparation. 150 patients who underwent total knee replacement were grouped into 3 groups- Group 1 (povidone-iodine scrub-and-paint), Group 2 (chlorhexidine gluconate paint after povidone-iodine scrub), and Group 3 (povidone-iodine paint after chlorhexidine gluconate scrub). 150 specimens of post-preparation swabs were obtained and cultured. To analyze the native bacteria at the total knee replacement incision site, 88 additional swaps were performed before skin preparation and cultured. RESULTS: The positive rate of bacterial culture after skin preparation was 5.3% (8/150). Positive rates of the groups were 12% (6/50) in group 1, 2% (1/50) in group, 2 and 2% (1/50) in group 3 and positive rates of bacterial culture after skin preparation in group 2 and group 3 were lower than in group 1 (p = 0.037). Among the 55 patients who had positive bacterial culture prior to skin preparation, 26.7% (4/15) in group 1, 5.6% (1/18) in group 2, and 4.5% (1/22) in group 3 were positive. Group 1 showed 7.64 times higher positive bacterial culture rate after skin preparation than group 3 (p = 0.084). CONCLUSION: During skin preparation prior to total knee replacement surgery, chlorhexidine gluconate paint after povidone-iodine scrub or povidone-iodine paint after chlorhexidine gluconate scrub had a superior effect on sterilizing native bacteria compared to povidone-iodine scrub-and-paint method.

Factors affecting the need of postoperative blood transfusion in elderly patients with intertrochanteric hip fracture.

INTRODUCTION: We investigated the risk factors that increased the frequency of blood transfusions in elderly patients with intertrochanteric hip fractures to determine blood transfusion risk before surgery and to take selective precautionary measures in the group at high risk for transfusion to ensure safe surgery. MATERIALS AND METHODS: We retrospectively reviewed the electronic medical records of 203 patients who underwent surgical fixation of intertrochanteric hip fractures from January 2015 to December 2020. We hypothesized that patient sex, age, body mass index, preoperative hemoglobin, preoperative platelet count, glomerular filtration rate (GFR), preoperative albumin level, American Society of Anesthesiologist score, intraoperative blood loss, duration of surgery, method of anesthesia, and time from injury to surgery would affect the need for blood transfusion. Student's t-test, Chi-squared test, and the one-way analysis of variance test were used to determine whether differences between variables in the transfusion and non-transfusion groups were significant. RESULTS: Unstable fractures (P = 0.002), general anesthesia (P = 0.028), lower preoperative hemoglobin levels (P < 0.001), and lower GFRs (P < 0.001) were identified as related to blood transfusions in univariate analysis. In multivariate logistic analysis, the need for allogeneic blood transfusion in unstable fractures was approximately 2.949 times higher than in stable fractures (P = 0.009). The risk in general anesthesia patients was about 2.953 times higher than in spinal anesthesia patients (P = 0.007). In addition, the need for allogeneic blood transfusion increased by about 1.293 times as preoperative hemoglobin levels decreased by 1 g/dL (P = 0.017) and increased by about 1.017 times as the GFR decreased by 1 mL/min/1.7m2 (P = 0.006). CONCLUSION: Low preoperative hemoglobin levels, low GFRs, general anesthesia, and unstable fractures in elderly patients with intertrochanteric hip fractures increased the risk of blood transfusion.

Prolonged ileus in traumatic pelvic ring injury patients who underwent arterial angio-embolization: A retrospective study.

Paralytic ileus occurs in up to 18% of the patients with pelvic bone fractures. The aim of this study is to determine if massive bleeding requiring arterial angio-embolization is related with the duration of ileus in patients with traumatic pelvic ring injuries. This retrospective study included 25 patients who underwent arterial angio-embolization for traumatic pelvic ring injuries. Data were collected from prospectively maintained databases of two independent hospitals. Demographic characteristics (such as age, sex, body mass index, and Charlson Comorbidity Index), cause of trauma, and severity of pelvic injuries were similar in the non-prolonged and prolonged ileus groups. As expected, the prolonged ileus group had a significantly longer duration of ileus than the non-prolonged ileus group (8.0 ±â€…4.2 days vs 1.2 ±â€…0.4 days, respectively; P < .001). The mortality rate was higher in the prolonged ileus group (20% vs 0%), but it was not significantly different (P = .13). Interestingly, the prolonged ileus group received significantly higher amounts of packed red blood cell transfusions (6.1 ±â€…2.1 units vs 3.8 ±â€…2.5 units; P = .02). The amount of packed red blood cell transfusions was associated with a greater risk of prolonged ileus development (P = .03, odds ratio = 2.04, 95% confidence interval = 1.08-3.88). This study supports the idea that the duration of the ileus is related with the amount of bleeding caused by the traumatic pelvic ring injury. In order to prevent further complications, conservative treatments of the ileus should be considered.

A Review of Sarcopenia Pathophysiology, Diagnosis, Treatment and Future Direction.

Sarcopenia is a progressive and generalized loss of skeletal muscle mass and function. The prevalence of sarcopenia was reported to be up to 29% in older persons in the community healthcare setting. Sarcopenia diagnosis is confirmed by the presence of low muscle mass plus low muscle strength or low physical performance. Sarcopenia management options include non-pharmacological and pharmacological approaches. Non-pharmacological approaches include resistance exercise and adequate nutrition. Of the two, resistance exercise is the standard non-pharmacological treatment approach for sarcopenia with significant positive evidence. Some dietary approaches such as adequate intake of protein, vitamin D, antioxidant nutrients, and long-chain polyunsaturated fatty acid have been shown to have positive effects against sarcopenia. Currently, no specific drugs have been approved by the Food and Drug Administration for the treatment of sarcopenia. However, several agents, including growth hormone, anabolic or androgenic steroids, selective androgenic receptor modulators, protein anabolic agents, appetite stimulants, myostatin inhibitors, activating II receptor drugs, ß-receptor blockers, angiotensin-converting enzyme inhibitors, and troponin activators, are recommended and have been shown to have variable efficacy. Future research should focus on sarcopenia biological pathway and improved diagnostic approaches such as biomarkers for early detection, development of consistently pre-eminent treatment methods for severe sarcopenia patients, and establishing sensitive measures for predicting sarcopenia treatment response.

The natural trends of C-reactive protein after hip arthroplasty for femoral neck fracture without infection.

ABSTRACT: The aim of this study was to estimate the degree of normalization of C-reactive protein (CRP) at 2-weeks and 4-weeks after hip arthroplasty after femoral neck fracture. We also wished to determine whether the degree of CRP normalization differs after total hip arthroplasty (THA) compared to bipolar hemiarthroplasty (BH). We also wanted to analyze the patient factors that may influence CRP normalization.We conducted a retrospective study of 135 patients who had undergone THA (32 cases) or BH (103 cases) for femoral neck fracture by single surgeon from January 2015 to December 2019. We analyzed CRP levels during the preoperative period, the early postoperative period, the 2-week postoperative period, and the 4-week postoperative period.In THA, CRP was normalized in 4 patients (12.5%) and in 15 patients (46.9%) within 2-weeks and 4-weeks after surgery, respectively. In BH, CRP was normalized in 16 patients (15.5%) and in 52 patients (50.5%) within 2-weeks and 4-weeks after surgery, respectively. There were no statistical differences between THA and BH. Compared to women, men were 3.78 (95% confidence interval, 1.05-13.63) times less likely to have normalized CRP at 2-weeks after surgery (P = .042). Compared to women, men were 3.01 (95% confidence interval, 1.44-6.27) times less likely to have normalized CRP at 4-weeks after surgery (P = .003).Only 50% of patient's CRP level was normalized during 4-week postoperative period. In men, CRP levels were significantly higher than women in whole period. In the case of THA, the CRP level was higher only in early postoperative period compared to BH, and there was no difference since then.

Natural course of hemoglobin level after total knee arthroplasty and the benefit of tranexamic acid injection in the joint.

ABSTRACT: We retrospectively investigated the natural course of hemoglobin (Hb) level after total knee arthroplasty (TKA) and identified the benefit of tranexamic acid injection at the operation field for unilateral TKA patients who have not received blood transfusions.There were 115 cases conducted by a surgeon who performed TKA without injecting tranexamic acid and 62 cases by another surgeon with injection. During 2-weeks of hospitalization, Hb level was checked on the day of surgery and 1, 2, 3, 5, 7, 11 days after surgery.Regardless of whether whom the operator was and tranexamic acid was injected or not, the same natural course of Hb level after TKA was observed. The lowest value of Hb was shown at postoperative day 3, after which it tended to recover. In repeated measures analysis of variance test, mean difference from preoperative Hb level showed a statistically significant difference between tranexamic acid injected and noninjected groups (P = .01). In post hoc test, the differences from preoperative Hb levels were significantly lower at all measurements in surgeon with injection of tranexamic acid.When deciding whether to transfuse after TKA, it should be noted that the patient tends to show the lowest Hb level on postoperative day 3. Also, the authors emphasize that tranexamic acid injection in the joint at the operation field is an effective method to reduce the loss of Hb after TKA.

Changes of acetabular anteversion according to pelvic tilt on sagittal plane under various acetabular inclinations.

Improper functional orientation of the acetabular cup can result in improper positions when dynamic pelvic positions are not considered. The purpose of this study was to evaluate changes on acetabular anteversion according to pelvic tilt under various acetabular inclinations. Two artificial pelvic models were selected for this study. Acetabular inclinations on the coronal plane were 25°, 32°, 50°, and 60°. Acetabular anteversion of all components were 15°. Changes of anteversion according to pelvic tilt were measured at angles of 0°, 10°, 20°, 30°, and 40°. Computer Navigation, PolyWare 3D pro, CT, and plain radiography were used to measure each angle. The anatomical anteversions against pelvic tilt were calculated using the following formulae: anatomical anteversion (°) = -14.48Χ + 90.18 (inclination angle 25°); anatomical anteversion (°) = -12.26Χ + 80.10 (inclination angle 32°); anatomical anteversion (°) = -7.468Χ + 61.13 (inclination angle 50°); and anatomical anteversion (°) = -5.328Χ + 44.84 (inclination angle 60°) (Χ: pelvic tilt angle). Radiographic anteversion against pelvic tilt were calculated using the following formulae: radiographic anteversion (°) = -9.50Χ + 57.09 (inclination angle 25°); radiographic anteversion (°) = -8.577Χ + 50.89 (inclination angle 32°); radiographic anteversion (°) = -6.794Χ + 45.73 (inclination angle 50°); radiographic anteversion (°) = -5.226Χ + 33.08 (inclination angle 60°). In conclusion, changes in anteversion according to pelvic tilt were lesser at higher degrees of acetabular inclination.

The advantage of navigation for knee with lateral femoral bowing in total knee arthroplasty.

PURPOSE: We have analyzed the surgical outcomes of primary total knee arthroplasty (TKA) using computer-assisted (CA) navigation in terms of postoperative coronal alignment depending on preoperative lateral femoral bowing. METHODS: We conducted a retrospective study of patients who have undergone navigated primary TKA from January 2016 through January 2020. Two hundred and ninety-nine cases with lateral femoral bowing of 3° or less were assigned to group 1, 95 cases of lateral femoral bowing between 3° and 5° were assigned to group 2, and 89 cases with lateral femoral bowing of more than 5° were assigned to group 3. The postoperative mechanical hip-knee-ankle (mHKA) angle was measured from scanograms, which were taken 3 months after surgery. The appropriate range of coronal alignment was set as 0 ± 3°. RESULTS: The number of outliers of mHKA occurred was 31 cases (10.4%) in group 1, 17 cases (17.9%) in group 2, and 17 cases (19.1%) in group 3. There was a significant correlation between the degree of lateral femoral bowing and the occurrence rate of mHKA outliers. Multiple variables logistic regression analysis showed occurrence rate of outliers in group 3 to be 2.04 times higher than group 1. After adjusting the patient's age, sex, body mass index, and preoperative HKA deformity, the occurrence rate of outliers in group 3 was still 1.96 times higher than group 1. CONCLUSION: The benefit of CA navigation during TKA in obtaining coronal alignment within 0 ± 3° may be lessened when the preoperative lateral femoral bowing is severely advanced.

C-reactive protein course after classical complication free total knee arthroplasty using navigation.

PURPOSE: The purpose is to estimate the degree of normalization of C-reactive protein (CRP) at 2 weeks and 4 weeks after uncomplicated total knee arthroplasty (TKA) using computer navigation. We also wish to determine whether the degree of normalization of CRP at 2 and 4 weeks differs after TKA performed in one knee and after TKA performed sequentially in both knees. We also want to analyze the patient factors that may influence the normalization of CRP. MATERIAL AND METHODS: We studied 400 knees who underwent primary computer-navigated TKA for treatment of advanced osteoarthritis: the TKAs were all performed by the same surgeon. We retrospectively analyzed CRP levels during the preoperative period, the early postoperative period (5-7 days), the 2-week postoperative period (12-14 days), and the 4-week postoperative period (25-30 days). We have assumed gender, age, body mass index (BMI), staged bilateral TKA, and preoperative CRP as the potential patient factors associated with CRP normalization. RESULTS: In unilateral TKA, CRP was normalized in 94 cases (34.3%) and in 219 cases (81.4%) within 2 weeks and 4 weeks after surgery, respectively. In second-knee, staged bilateral TKA, CRP was normalized in 46 cases (35.1%) and in 104 cases (79.4%) within 2 weeks and 4 weeks after surgery, respectively. There were no statistical differences between unilateral TKA and second-knee, staged bilateral TKA during the 2-week postoperative and the 4-week postoperative period. Compared to women, men were 1.99 times less likely to have normalized CRP at 2 weeks after surgery (P = 0.02). CONCLUSION: CRP was less likely to normalize during the 2-week postoperative period in men than it is in women, while there was no difference between men and women in the normalization of CRP during the 4-week postoperative period. There were no statistical differences in the course of CRP levels after unilateral TKA and staged bilateral TKA during the 2-week postoperative and the 4-week postoperative period.

Appropriateness of the Use of Navigation System in Total Knee Arthroplasty.

BACKGROUD: The aim of this study was to evaluate the difference between the planned and verified actual values in total knee arthroplasty (TKA) performed using a navigation system. METHODS: Sixty patients who underwent primary TKA for knee pain from March 2018 to July 2018 were included in this study. All patients underwent TKA using the latest version of a computer navigation system (Kick ver. 2.6). All TKA procedures were performed by the same surgeon. The appropriateness of the use of navigation system in each of the several steps during the operation was investigated. Implant size was assessed using a preoperative template and after registration of landmarks with the navigation system. Intraoperative measurement was conducted using a femoral sizing implant apparatus. The difference between the planned value based on the navigation system and the actual cutting value was investigated. Intraoperatively confirmed hip-knee-ankle angle was also compared to the angle measured at postoperative 3 months. RESULTS: The average time spent on the registration process was 242 seconds (range, 205-345 seconds). Intraoperative femoral component size tended to be smaller than the size recommended by the navigation system. A significant difference between the planned distal femoral cutting level (9.08 ± 0.40 mm) and the verified actual cutting level (9.87 ± 1.39 mm) was identified (p < 0.05). The difference between the planned lateral and medial tibial resection levels (10.12 ± 0.34 mm and 4.47 ± 2.17 mm, respectively) and the verified actual lateral and medial tibial resection levels (9.07 ± 1.45 mm and 3.48 ± 2.00 mm, respectively) was statistically significant. Distal femoral cutting angle in sagittal plane was significantly different but femoral and tibial cutting angles showed no significant difference between the planned and verified values. At full extension, the average coronal alignment of the implant recorded after insertion of the actual implant using the navigation system was 0.23° ± 0.51° varus and showed no significant difference from the alignment measured at postoperative 3 months (0.45° ± 0.58°). CONCLUSIONS: When performing navigation-assisted TKA, surgeons should aware that frequent errors can occur on the femoral cutting level, tibial cutting level, and implant sizing despite its reported advantage in defining the mechanical limb axis.

IgG Seroprevalence of COVID-19 among Individuals without a History of the Coronavirus Disease Infection in Daegu, Korea.

BACKGROUND: Seroprevalence studies of coronavirus disease 2019 (COVID-19) from many countries have shown that the number of undiagnosed missing cases is much larger than that of confirmed cases, irrespective of seroprevalence levels. Considering the strategy of Korea entailing massive testing and contact tracing from the beginning of epidemic, the number of undiagnosed missing cases in Korea may be negligible. This study was conducted to estimate the seroprevalence of COVID-19 among individuals who were never diagnosed with COVID-19 in Daegu, the epicenter of COVID-19 epidemic in Korea. METHODS: Serologic testing for immunoglobulin G antibody based on immunochromatographic assay was conducted in 103 patients and 95 guardians aged 18 to 82 years without any history of COVID-19 diagnosis, who visited outpatient clinics of a single university-affiliated hospital from May 25 to June 5, 2020. RESULTS: The estimated seroprevalence was 7.6% (95% confidence interval, 4.3%-12.2%) with 15 positive cases. Among them, only one had a polymerase chain reaction (PCR)-confirmed case among their close contacts and 13 did not experience COVID-19-related symptoms. Seroprevalence was similar between patients and guardians. Based on this figure, the number of undiagnosed missing cases in Daegu was estimated to be a dozen times more than the number of confirmed cases based on PCR testing. CONCLUSION: Despite the limitation of a small and unrepresentative sample, this is the first study on seroprevalence of COVID-19 in Korea. Our study suggested that the number of undiagnosed missing cases was substantial even with the stringent strategy adopted in Korea, similar to that of other countries.

Sleep Disturbance Strongly Related to the Development of Postoperative Delirium in Proximal Femoral Fracture Patients Aged 60 or Older.

PURPOSE: Post-fracture sleeping disorders can lead to a deterioration of mental and physical health and delay recovery to pre-fracture status. Here, an analysis was conducted to determine if sleep disturbance is a risk factor for delirium in patients older than 60 years of age with surgically treated proximal femoral fractures. MATERIALS AND METHODS: This retrospective study included 316 patients with surgically treated proximal femoral fractures between January 2014 and December 2016; 33 patients were removed from analysis due to exclusion criteria. Confirmation of delirium was made by a neurologist upon consultation for cognitive impairment and sleeping disorders were confirmed by a doctor or nurse based on the Pittsburgh sleep quality index. Potential risk factors other than a sleep disorder (e.g., history of cognitive impairment, medical illness, preoperational levels of albumin and hemoglobin, transfusion) were also analyzed as variables for the development of delirium. RESULTS: The sensitivity and specificity of a sleeping disorder as a risk factor for the development of delirium were 0.75 and 0.76, respectively; the positive and negative predictive values were 0.64 and 0.93, respectively. A sleeping disorder was significantly related to the development of the delirium (odds ratio adjusted for age, sex and body mass index was 5.78, P<0.01). In those with a history of cognitive impairment, the adjusted odds ratio for the development of delirium was 6.03 (P<0.01). CONCLUSION: Sleeping disorders occurring after a surgically repaired proximal femoral fracture in patients 60 years of age or older could be an independent predictive factor of delirium.

Acquisition of coronal alignment according to the degree of varus deformity in total knee arthroplasty using computer-assisted navigation.

PURPOSE: We have analyzed the surgical outcomes of primary total knee arthroplasty (TKA) using computer-assisted navigation that were performed by a single surgeon in terms of postoperative coronal alignment depending on preoperative varus deformity. METHODS: We conducted a retrospective study of patients who have undergone navigated primary TKA from January 2016 through December 2019. Two hundred and fifty-six cases with varus deformity of 10° or less were assigned to group 1, and 216 cases with varus deformity of more than 10° were assigned to group 2. The postoperative mechanical hip-knee-ankle (mHKA) angle was measured from scanograms which were taken preoperatively and 3 months after surgery. The postoperative mHKA angle was targeted to be 0°, and the appropriate range of coronal alignment was set as 0 ± 3°. RESULTS: The Pearson correlation showed a significant correlation with the degree of preoperative varus deformity and with the absolute error of postoperative mHKA (p = 0.01). Among all patients, 64 cases (13.6%) were detected as outliers (mHKA > 0° ± 3°) at 3 months after surgery. Of the 64 cases, 25 cases (9.8%) were affiliated to group 1 and 39 cases (18.1%) were affiliated to group 2. Group 2 showed significantly higher occurrence of outliers than group 1 (p = 0.01). Multiple variables logistic regression analysis, which analyzed the difference in the occurrence rate of outliers (mHKA > 0° ± 3°), showed that the occurrence rate of group 2 was 2.04 times higher than group 1. After adjusting for patient's age, gender, and body mass index, the occurrence rate of outliers in group 2 was 2.01 times higher than group 1. CONCLUSION: The benefit of computer-assisted navigation during TKA in obtaining coronal alignment within 0 ± 3° may be lessened when the preoperative varus deformity is severely advanced.

Results of primary THA using 36 mm femoral heads on first-generation highly cross-linked polyethylene in patients less than 60 years of age: Minimum 10-year follow-ups.

PURPOSE: Long-term results of total hip arthroplasty (THA) using highly cross-linked polyethylene (HXLPE) and metal femoral head with more than 10 years of follow-up have already been reported. However, most studies included results with a head size of 28 mm that could affect wear rates. The aim of this study was to evaluate the results of 36-mm metallic femoral heads on first-generation HXLPE in patients less than 60 years of age with a minimum follow-up of 10 years. METHODS: Retrospective analysis included 54 cases from 47 patients. The mean age at the time of surgery was 47.22 years and the mean follow-up period was 131.04 months. Porous-coated cementless acetabular cups (Trilolgy®; Zimmer Inc., Warsaw, Indiana, USA) and HXLPE acetabular liners (Longevity®; Zimmer Inc.) were used for all cases. Acetabular cup abduction angles, anteversion angles, and wear rates of liner were measured using polyWare pro 3D distal version 5.10. RESULTS: The average modified Harris hip score at the final follow-up was 88.48 (range 80-96). Average Merle d'Aubigne and Postel score was 15.57 (range 14-18). There was no acetabular cup or femoral stem failing due to aseptic loosening. The average steady-state wear rate determined using radiographs taken at 1 year postoperatively and at the latest follow-up was 0.053 ± 0.025 mm/year. There were no statistically significant differences in liner wear rate with respect to age, variety of the femoral stem, or liner thickness. CONCLUSION: Results of THA with 36-mm metallic femoral heads on first-generation HXLPE in patients less than 60 years of age were satisfactory.

Pseudotumor mimicking iliacus muscle abscess following a total hip arthoplasty with metal on metal articulation: A case report.

RATIONALE: Cases of pseudotumor complicated after THA with metal-on-metal articulation as a bearing surface have been reported. Most of the pseudotumors occurred near or inside the hip joint, and usually have similar features with the infectious condition. We herein report a case of pseudotumor with huge size in the pelvic cavity mimicking features of iliacus muscle abscess. PATIENTS CONCERNS: A 70-year-old female was referred to our emergency department due to huge mass in her right pelvic area on abdominal CT. She complained of mild febrile sensation, generalized weakness, and pain in her right leg for several months. The patient underwent metal-on-metal bearing THA 11 years ago for treatment of right-sided hip pain due to avascular necrosis. DIAGNOSIS: Percutaneous catheter drainage was performed for both therapeutic and diagnostic reasons. No microbes were cultured from the drained fluid, and signs of chronic inflammation were shown on pathology slide samples. The patient showed positive allergic reactions to cobalt and captan on allergic patch test, and serum cobalt levels was increased as 46.78 µg/L (normal value, 0.11-0.64 µg/L). Biopsy samples of the cyst were consistent with the histological findings of pseudotumor reported by Willert et al. INTERVENTION:: For the treatment of infection, primarily, the patient was surgically treated by irrigation, debridement, and bone bead insertion. Then, after 4 weeks of antibiotic treatment, revision surgery changing the metal-on-metal articulation into poly-on-metal articulation was performed. OUTCOMES: CT scan at 1 year after surgery showed no findings of cyst inside the pelvic cavity. Although the patient complained of right sided hip pain (VAS score 2), she was able to perform activities of daily living. LESSONS: In patients who underwent metal-on-metal THA, pseudotumor mimicked the feature of periprosthetic infection may occur not only inside the hip joint but also in the pelvic cavity.

Preoperative Temporary Discontinuation of Aspirin Medication Does Not Increase the Allogeneic Transfusion Rate and Blood Loss in Primary Total Hip Arthroplasty.

PURPOSE: This study aims to determine whether preoperative temporary discontinuation of aspirin (100 mg/d) use is a safe procedure does not increase blood loss and the need for transfusion after total hip arthroplasty (THA). MATERIALS AND METHODS: This study retrospectively reviewed 219 patients who underwent consecutive primary THA from January 2012 to December 2018. They were divided into the experimental group (42 cases) that discontinued aspirin intake 7 days before surgery and the control group (150 cases) that had no history of use of antiplatelet agents. To compare initial blood loss between the two groups, we analyzed the changes hemoglobin (Hb) levels and hematocrit values measured preoperatively and in lowest values measured during three days after surgery. In addition, transfusion rate was compared within the first two postoperative weeks between the two groups. A multiple logistic regression was performed to assess the association of transfusion with age, gender, use of antiplatelet agents, preoperative anesthetic risk, body weight and preoperative Hb. RESULTS: No statistically significant difference was found in the changes in lowest Hb level (P=0.30) and hematocrit value (P=0.14) measured preoperatively and for three days after surgery between the experimental group and the control group. There was no statistically significant association between transfusion and the use of antiplatelet agents, and preoperative Hb level was identified as a factor that affected the need for transfusion (odds ratio, 0.427; P=0.001). CONCLUSION: Preoperative temporary discontinuation of aspirin use for 7 days before surgery did not increase initial blood loss after THA and the need for transfusion in the first two postoperative weeks compared to patients with no history of use of antiplatelet agents.