Clinical Efficacy of Nasal Screening and Methicillin-Resistant Staphylococcusaureus Decolonization in Total Hip Arthroplasty without Chlorhexidine Soap or Vancomycin.

Purpose: Nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) is a known risk factor for periprosthetic joint infection (PJI). In our facility, preoperative prophylaxis with mupirocin without the chlorhexidine soap scrub or vancomycin was consistently implemented for more than 15 years. This study aimed to evaluate the current screening and treatment of intranasal MRSA colonization in our elective primary THA patient population. Methods: All patients who underwent primary THA between April 2011, and March 2021 were included in this analysis. All patients were screened preoperatively for nasal MRSA approximately 1 month before surgery. Patients with nasal MRSA contamination are treated with topical mupirocin to eradicate the bacteria before surgery. The patients were examined again approximately two weeks before surgery. We evaluated the current screening and treatment of intranasal colonization with MRSA in our elective primary total hip arthroplasty (THA) patient population. Results: Out of 6251 patients, 106 (1.7%) had nasal MRSA contamination. The bacteria were not eradicated in three (3.6%) patients at the second screening. Twenty-two joints (0.35%) out of the 6251 had deep infections. Only 1 patient out of the 106 MRSA nasal carriers suffered from PJI. Twenty-one of the 6145 non-carriers had PJI. The difference between the prevalence of nasal MRSA contamination and the incidence of deep infections was not statistically significant. Conclusion: Our findings suggest that screening of all patients for nasal MRSA before THA followed by mupirocin calcium treatment if needed is sufficient PJI prophylaxis.

Denosumab prevented periprosthetic bone resorption better than risedronate after total hip arthroplasty.

INTRODUCTION: Periprosthetic fracture caused by periprosthetic bone loss is an important concern in total hip arthroplasty (THA). Denosumab has been approved for postmenopausal women with osteoporosis who are at high risk of fracture. In this randomized controlled trial, we compared the effects of denosumab and risedronate on periprosthetic bone mineral density (BMD) after THA. MATERIALS AND METHODS: The current study analyzed 108 patients who were scheduled to have THA. For 2 years, the patients were randomly assigned to the following two treatment groups: denosumab (60 mg subcutaneously every 6 months) or risedronate (17.5 mg oral weekly). The BMD changes in all Gruen zones and bone turnover markers were measured at the 5th postoperative day (baseline) and 6, 12, 18, and 24 months postoperatively. RESULTS: The mean BMD in zones 1, 2, 6, and 7 was significantly higher with denosumab all administration at all postoperative time points compared to the risedronate group. The mean percentage changes in the BMD in these zones from baseline to 24 months postoperatively were + 11.9, + 2.9, + 8.1, and + 5.9% with denosumab group and - 9.6% -3.6, - 2.3, and - 19.2% with risedronate, respectively. The osteoclastic marker, tartrate-resistant acid phosphatase-5b (TRACP-5b), was significantly lower in the denosumab group compared to the risedronate group by 2 months. CONCLUSION: Denosumab is more effective in preventing periprosthetic bone resorption than risedronate in the proximal femur. It also increased BMD around the stem implant following THA.

Nutritional Factors Related to Muscle Weakness 1 Year after Total Hip Arthroplasty: A Case-Control Study.

OBJECTIVES: Prolonged muscle weakness after total hip arthroplasty (THA) remains a problem. Despite increasing physical activity up to 3 years after surgery, muscle strength was decreased to 80-90% of the healthy side 2 years after THA. The objective of the present study was to identify the nutritional factors related to muscle weakness 1 year after THA. METHODS: Persons who underwent THA were divided into 2 groups according to the cutoff point of knee extensor strength that represents functional limitation: a normal-strength group of 71 persons and a muscle weakness group of 91 persons. The investigators assessed lower limb isometric strength, the 10-m timed gait test, and daily intakes of energy and nutrients from preoperative to 1 year after THA. The differences in nutrient intakes between the 2 groups (normal-strength group and muscle weakness group) were examined by multiple logistic regression analysis. RESULTS: There was a significant difference between the groups in energy intake. Daily protein intake was related to knee extension strength gain above the cutoff point 1 year after THA. CONCLUSIONS AND IMPLICATIONS: The present study suggested that to prevent prolonged muscle weakness after THA, a sufficient protein intake as well as an exercise intervention may be needed even half a year or after.

Prevalence of locomotive syndrome in Japanese patients more than 10 years after total hip arthroplasty: A cross-sectional cohort study.

BACKGROUND: Locomotive syndrome (LS) is a high risk condition that requires nursing care. It is important to investigate the prevalence of and factors related to LS to maintain a healthy life expectancy for patients; however, only a few reports have focused on the relationship between LS and total hip arthroplasty (THA). The purpose of this study was to evaluate the prevalence of LS and to identify factors associated with LS in patients more than 10 years after THA. METHODS: This is a cross-sectional cohort study. Patients were assessed via a mail survey that included items regarding demographic data, cardiometabolic and motor disorders, the incidence of falls, physical activity level, and the 25-question Geriatric Locomotive Function Scale (GLFS-25) questionnaire. LS was defined as having a score ≥16 on the GLFS-25, and the respondents were categorized into two groups: an LS group and a non-LS group. The prevalence of LS was calculated in each gender and age group. Differences in variables between the groups were determined using the unpaired t-test and chi-squared test. RESULTS: A total of 593 patients were included in the study (mean age, 70.4 years; 525/593 females). According to the GLFS-25, 164 patients (27.7%; 21.1% men and 28.8% women) were classified as having LS, which increased with age. In addition, compared with the non-LS group, the LS group had a significantly higher prevalence of motor diseases, cardiometabolic diseases, and falls and significantly lower levels of activity. CONCLUSION: These findings suggest that the prevalence of LS in patients more than 10 years after THA is 27.7%. The result suggest that the prevalence of LS in patients more than 10 years after THA is similar to the prevalence of LS in the general elderly population. Furthermore, LS is related to not only motor diseases but also cardiometabolic diseases.

Adverse Local Tissue Reaction and Late-Onset Eosinophilic Gastroenteritis After Primary Total Hip Arthroplasty: A Case Report.

CASE: A 67-year-old woman suffered from chronic diarrhea at 10 years after right total hip arthroplasty. She also had a pseudotumor caused by an adverse local tissue reaction (ALTR) in her right pelvis. We performed revision arthroplasty, in part because we suspected the diarrhea may have been associated with the intrapelvic pseudotumor. She was later diagnosed with eosinophilic gastroenteritis (EGE). CONCLUSION: Although these two diseases were thought be be related through a similar immune reaction, our patient's clinical course suggests that the ALTR and EGE were independent events.

Incidence of postoperative complications and non- periprosthetic fractures after total hip arthroplasty: A more than 10-year follow-up retrospective cohort study.

OBJECTIVE: Postoperative complications and non-periprosthetic fractures (NPPFs), which was defined as a fracture existing non- periprosthetic implant, after total hip arthroplasty (THA) have a negative effect on the patients' ability to perform activities of daily living. Thus, investigating these incidences of patients after THA will be valuable as it lead to a more strategic physical therapy interventions and advanced research to prevent these problems. The purpose of this study was to investigate the incidence of postoperative complications related to implants and NPPFs in patients after THA, a more than 10-year follow-up. METHODS: This is a retrospective cohort study. A total 892 patients with hip osteoarthritis who underwent primary THA were analyzed (age at surgery was 45-79 years; 805 women; the average follow-up period was 12.4-year). The postoperative complications related to implants and NPPFs were calculated using data from their medical records. RESULTS: The postoperative complications occurred in 37 patients, and NPPFs occurred in 72 patients, who were significantly older, and hip and knee OA diagnosis, compared to patients without NPPFs ( p <.05). The most common cause of NPPFs was minor trauma. In patients aged ≧ 65 years, significantly more NPPFs occurred during the first year after surgery( p <.05). CONCLUSION: More than 10-year after THA, the incidence of NPPFs was higher than that of postoperative complications related to implants. Older patients who had hip and knee OA were a significantly higher risk of developing NPPFs due to falls within the first year after surgery.

Predictors of falls in patients during the first year after total hip arthroplasty: A prospective cohort study.

BACKGROUND AND PURPOSE: Since falls after total hip arthroplasty (THA) cause severe complications such as dislocation and fractures around the femoral stem, it is important to investigate what factors predict of falls. Thus, investigating predictors of falls in patients waiting for THA would be valuable as it lead to more strategic interventions to prevent these problems. The purpose of this study was to evaluate the predictors of falls in patients during the first year after THA. METHODS: This is a prospective cohort study. A total of 157 patients who underwent THA for unilateral hip osteoarthritis were analyzed. The incidence of falls during the first year after THA was monitored, and patients were classified into a "faller" and "non-faller" group. The following factors were compared between the two groups: demographic data (age, sex, body mass index, leg length discrepancy, length of hospital stay, and history of falling), preoperative hip abductor muscle strength, functional performance (single leg stance and maximum walking speed), pain during walking, and physical activity. RESULTS: On multivariate logistic regression analysis, preoperative hip abductor muscle strength on the affected side and a history of falling were predictors of falls during the first year after THA. On subsequent receiver operating characteristic curve analysis, preoperative hip abductor muscle strength on the affected side was retained as a significant predictor, with a cut-off strength of 0.46 Nm/kg differentiating the faller and non-faller groups with a specificity of 73.6%, specificity of 50.0%, and area under the curve of 70.2%. CONCLUSIONS: Finding from the present study suggested that clinicians should focus on low preoperative hip abductor muscle strength on the affected side and a history of falling to prevent falls during the first year after THA.

Clinical efficacy of risk-stratified prophylaxis with low-dose aspirin for the management of symptomatic venous thromboembolism after total hip arthroplasty.

BACKGROUND: Pulmonary thromboembolism (PTE) and deep vein thrombosis (DVT) are serious complications after total hip arthroplasty (THA). Aspirin has been considered a safe and cost-effective prophylaxis for venous thromboembolism (VTE), and there have been some reports about the incidence of PTE (0%-0.57%) and DVT (0.1%-0.35%) with low-dose aspirin for prophylaxis after THA. The aim of this study was to investigate the incidence of postoperative symptomatic VTE in our hospital and to evaluate the clinical efficacy of our prophylactic regimen. PATIENT AND METHODS: We retrospectively reviewed the medical records of consecutive patients who underwent THA in our hospital between 2011 and 2016. A total of 3295 hips (male: 337 patients, 365 hips; female: 2527 patients, 2930 hips) were enrolled in this study. Patients were divided into low-risk and high-risk groups. Low-risk patients were administered aspirin (100 mg/day) for 28 days postoperatively. High-risk patients, such as those diagnosed with obesity and/or with a history of VTE, received anticoagulants (enoxaparin or edoxaban) for 5 days postoperatively, followed by a dose of aspirin for 28 days. Based on our criteria, 218 of 3295 hips were considered high risk. RESULTS: No VTE-related mortality was observed. One patient developed symptomatic PTE, and one patient developed symptomatic DVT. Both were successfully treated. Postoperative fatal bleeding or bleeding from any organ such as gastrointestinal and cerebral hemorrhage were not observed. A low incidence (0.03%) was observed for symptomatic DVT and PTE. CONCLUSIONS: This study demonstrated that the hospital's risk-stratified protocol using low-dose aspirin or anticoagulants was clinically effective in preventing symptomatic VTE. These results were considerably better than those reported from Western countries. However, all patients in this study were the Japanese. It was unclear whether similar results were given to non-Japanese patients. Therefore, this protocol needs severe carefulness to be applied to non-Japanese populations.

Effect of exercise therapy combined with branched-chain amino acid supplementation on muscle strengthening in persons with osteoarthritis.

BACKGROUND: Improving lower limb muscle strength is important in preventing progression of osteoarthritis (OA) and its symptoms. Exercise with branched-chain amino acid (BCAA) supplementation has been reported to affect protein anabolism in young and elderly persons. However, few studies provided daily BCAAs for patients with OA. OBJECTIVE: This study examined the effects of combined BCAAs and exercise therapy on physical function improvement in women with hip OA scheduled for total hip arthroplasty. METHODS: The subjects were 43 women with OA (age: 64.2 ± 9.4). The participants were randomly divided into two groups: BCAA ( n = 21 ) and control ( n = 22 ). The combined therapy was carried out for one month. Exercise intervention involved hip abductor muscle exercise in both groups. For the nutritional intervention, 6 g of BCAAs or 1.2 g of starch were consumed within 10 min before starting the exercise. RESULTS: There was a marginally significant difference in the main effect between the groups in 10-m timed gait time. The improvement rate in hip abductor muscle strength of the contralateral side was significantly greater in the BCAA group. CONCLUSION: By combining BCAA intake and exercise therapy, a significant improvement in hip abductor muscle strength of the contralateral side was achieved in women with OA.

Patients 10 years after total hip arthroplasty have the deficits in functional performance, physical activity, and high fall rate compared to healthy adults.

Background Long-term results in muscle strength, physical activity (PA), and functional improvement after total hip arthroplasty (THA) have not been studied. The purpose of this study was to evaluate the deficits in functional performance, PA, and high fall rate in patient 10 years after THA compared to healthy adults. Methods The subjects were 58 patients who underwent primary THA for unilateral hip osteoarthritis 10 years, and 46 healthy adults. Hip abductor strength, balance function (single-leg stance time), Maximal Walking Speed (MWS), fall rate, and PA (IPAQ short ver.) were evaluated. The unpaired t-test and χ2 test were used to assess differences between the groups. Statistical significance was set at p value <0.05. Results Compared to healthy adults, THA patients had 9.5% less hip abductor muscle strength on the operated side, 42.1% shorter single-leg stance time on the operated side, 14.8% slower MWS, 2.0 times less High-PA group, and 2.8 times higher fall rate (p<0.05). Conclusion This study showed that hip abductor muscle strength, gait speed, balance function, and PA were significantly lower in patients 10 years after THA than in healthy adults. Additionally, the fall rate was significantly higher in patients 10 years post-THA than in healthy adults.

Effects of perioperative factors and hip geometry on hip abductor muscle strength during the first 6 months after anterolateral total hip arthroplasty.

[Purpose] The importance and effect of hip joint geometry on hip abductor muscle strength are well known. In addition, other perioperative factors are also known to affect hip abductor muscle strength. This study examined the relative importance of factors affecting hip abductor muscle strength after total hip arthroplasty. [Subjects and Methods] The subjects were 97 females with osteoarthritis scheduled for primary unilateral THA. The following variables were assessed preoperatively and 2 and 6 months after surgery: isometric hip abductor strength, radiographic analysis (Crowe class, postoperative femoral offset (FO)), Frenchay Activities Index, compliance rate with home exercise, Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ), and demographic data. Factors related to isometric hip abductor muscle strength 2 and 6 months after surgery were examined. [Results] Significant factors related to isometric hip abductor muscle strength at 2 and 6 months after surgery were, in extraction order: 1. isometric hip abductor muscle strength in the preoperative period; 2. BMI; and 3. the JHEQ mental score at 2 and 6 months after surgery. [Conclusion] Preoperative factors and postoperative mental status were related to postoperative isometric hip abductor strength. FO was not extracted as a significant factor related to postoperative isomeric hip abductor strength.

Re-dislocation after revision total hip arthroplasty for recurrent dislocation: a multicentre study.

PURPOSE: Although most case of dislocations after total hip arthroplasty (THA) can be managed with conservative treatment, recurrent dislocation may require surgical intervention. This multicentre study was conducted to evaluate the re-dislocation rate after revision THA for recurrent dislocation, and to determine the risk factors for re-dislocation. METHODS: We retrospectively reviewed the 88 hips in 88 patients who underwent revision THA for recurrent dislocation at five institutions between 1995 and 2014. The mean patient age at surgery was 68.5 years and the mean follow-up period was 53.1 months. Multivariate logistic regression was performed to identify risk factors for re-dislocation. RESULTS: Sixteen hips in 16 patients (18.2 %) re-dislocated at a mean of 25.5 months (range, 1-83 months) after revision THA. Multivariate analysis identified osteonecrosis of the femoral head (odds ratio [OR] = 5.62 vs. osteoarthritis) and a femoral head size < 32 mm (OR = 3.86) as independent risk factors for re-dislocation. Eight hips required additional revision THA for re-dislocation. CONCLUSION: The re-dislocation rate after revision THA for recurrent dislocation remains high, suggesting the need for prevention measures. We recommend the use of a femoral head size ≥ 32 mm.

Additional intraarticular tranexamic acid further reduced postoperative blood loss compared to intravenous and topical bathed tranexamic acid in total hip arthroplasty: a retrospective sequential series study.

BACKGROUND: Topical tranexamic acid (TXA) administration has been described to be effective in decreasing blood loss in total hip arthroplasty (THA). The aim of this retrospective study was to evaluate whether topical intraarticular TXA administration in addition to intravenous (IV) and topical bathed TXA further reduces blood loss in THA patients. STUDY DESIGN AND METHODS: Four-hundred patients were enrolled in this sequential series study with two different phases during four different time periods. Patients were divided based on TXA usage and route of administration: those with and without IV TXA (IVTA-I and no-IVTA groups, respectively) and those with and without intraarticular TXA (TITA and IVTA-II groups, respectively). Both IVTA-II and TITA groups had IV TXA, and all four groups used topical bathed TXA. These four groups had 100 cases each. The primary outcomes were evaluated with total blood loss and postoperative hemoglobin level. RESULTS: The total blood loss was 1106 and 875 mL in the no-IVTA and IVTA-I groups, respectively (p < 0.05). Postoperative Hb was 10.9 and 11.51 g/dL in the no-IVTA and IVTA-I groups, respectively (p < 0.05). Total blood loss was 813 and 646 mL in the IVTA-II and TITA groups, respectively (p < 0.05). Intraarticular with IV and bathed TXA administration was more effective than IV and bathed TXA in reducing blood loss. CONCLUSION: This study suggests that the combined administration of topical intraarticular, bathed, and IV TXA was effective in reducing blood loss in THA patients.

Relationship between peri-operative outcomes and hospital surgical volume of total hip arthroplasty in Japan.

BACKGROUND: This study aimed to evaluate the relationship between peri-operative complication of total hip arthroplasty (THA) and hospital surgical volume. METHODS: We reviewed discharge administrative data from 8321 patients who underwent primary THA between July and December 2008. Relationships between complications and surgical volume were analyzed with multivariate logistic regression models including age, sex, and Charlson comorbidity index. Hospitals were categorized into four groups according to the 6-month volume of THA procedures. RESULTS: The most frequent complication was dislocation (1.41%). Next was infection (1.24%). Fracture and pulmonary embolism occurred in less than 1% of procedures. Patients who underwent THA in hospitals with the highest surgical volume had lower risk of dislocation and infection than those treated in the hospitals with the lowest surgical volume (odds ratio [OR] 0.321, 95% confidence interval [CI] 0.167-0.572 and OR 0.123, 95% CI 0.020-0.421). Patients aged 65 years and older were associated with increased risk of dislocation (OR 2.342, CI 1.555-3.624) and fracture (OR 2.799, CI 1.372-6.301). Females demonstrated lower risk of dislocation (OR 0.558, CI 0.352-0.869) and infection (OR 0.560, CI 0.365-0.882). CONCLUSION: These results indicated that the increase in the risk of peri-operative dislocation of primary THA may be associated with low hospital surgical volume as well as age and male sex.

Femoral anterior tangent line of the osteoarthritic knee for determining rotational alignment of the femoral component in total knee arthroplasty.

Several reference axes have been used to establish femoral rotational alignment during total knee arthroplasty. The current study examined the configuration of the anterior surface of the femur immediately proximal to the trochlea as an alternative rotational landmark. An analysis of computed tomographic images of 150 knees with osteoarthritis indicated that the configuration of the surface is mostly flat or slightly depressed, and the line tangential to the surface (femoral anterior tangent line; FAT line) was consistently determined to be 12.2° ± 3.6° internally rotated to the transepicondylar axis. This value was relatively constant and as reliable as the femoral anteroposterior axis for determining rotational alignment. In addition, the FAT line was not affected by the degree of the varus-valgus deformity of the osteoarthritic knees.

Wear of sequentially enhanced 9-Mrad polyethylene in 10 million cycle knee simulation study.

Highly crosslinked polyethylene (HXPE) has been shown to be effective in reducing wear in total hip replacements. HXPE has not found widespread use in TKR, because the crosslinking inevitably leads to reductions in critical properties such as toughness and fatigue strength. Sequentially enhanced crosslinking (SXPE) have been suggested for improved wear resistance for tibial inserts with maintenance of mechanical properties and anticipated high oxidation resistance superior to conventional polyethylene (XLPE). We compared the wear of SXPE (9Mrad) to XLPE inserts (3Mrad) to 10 million cycles. Triathlon femoral condyles were identical in both. This is the first wear study of SXPE inserts. According to the power law relating irradiation dose to wear of XLPE inserts, wear of 9 Mrad inserts should be reduced by 70% compared to 3Mrad controls. The wear rates of the SXPE inserts were reduced by 86% at 10 million cycles duration, somewhat greater than predicted. The one prior investigation by the manufacturer reported a 79% wear reduction for SXPE compared to controls in a 5 million cycle simulator study in knee design and test parameters. There were important differences between the two studies. Nevertheless there clearly appeared to be a major benefit for sequentially enhanced polyethylene in tibial inserts. This combined wear reduction of 80-85% with improved oxidation resistance and retention of mechanical properties may prove beneficial for active patients who may otherwise risk high wear rates over many years of use.

Wear in molded tibial inserts: knee simulator study of H1900 and GUR1050 polyethylenes.

Hi-fax 1900 tibial inserts were used in the IB-1 total knee replacement (TKR) beginning 1978, soon followed by the AGC design. Such direct compression molded (DCM) inserts was relatively immune to oxidation. Unfortunately the Hi-fax 1900 resin (H1900) was taken off the market in year 2004. As an alternate, GUR1050 was introduced in the Vanguard TKR. However there appeared to be little or no wear comparisons of molded inserts. Therefore the study aim was to compare wear performance of GUR1050 to the historical H1900. The hypothesis was that Hi-fax and GUR1050 would show comparable wear performance. The Vanguar was a posterior-cruciate sacrificing design (Biomet Inc.). All tibial inserts were sterilized by gamma-radiation (3.2 Mrad) under argon. A 6-channel, displacement-controlled knee simulator was used with serum lubricant (protein concentration 20 mg/mL). Wear assessments were by gravimetric methods and linear regression techniques. The gross weight-loss trends over 2.5 Mc duration demonstrated excellent linear behavior with good agreement between TKR sets (<+/-10%). Fluid sorption artifacts in control represented less than 5% of gross wear magnitudes. Thus suitable corrections could be made in determining net wear. The H1900 and GUR1050inserts demonstrated net wear-rates of 3.6 and 3.4 mm(3)/Mc, respectively. This difference was not found to be statistically significant. This wear study demonstrated that GUR1050 inserts were indistinguishable from the Hi-fax 1900 in terms of laboratory wear performance, proving our hypothesis. Given the excellent clinical history of DCM Hi-fax 1900, the GUR1050 should be an ideal candidate for TKR.