Visceral Adipose Tissue Percentage Compared to Body Mass Index as Better Indicator of Surgical Outcomes in Women With Obesity and Endometrial Cancer.

STUDY OBJECTIVE: To assess the impact visceral adipose tissue percentage (VAT%) on surgical outcomes during minimally invasive surgery in obese women with endometrial cancer. DESIGN: Retrospective observational cohort study. SETTING: Mie University Hospital, Japan. PATIENTS: Of the 73 women (body mass index [BMI] >30 kg/m2) with obesity and primary endometrial cancer, 52 underwent robotic surgery, while 21 underwent laparoscopic surgery between April 2014 and December 2022. INTERVENTIONS: We investigated the correlation between surgical outcomes (operative time and blood loss) and obesity (BMI and visceral adipose tissue percentage [VAT%]). MEASUREMENTS AND MAIN RESULTS: Abdominal fat-related parameters were measured at the level of the umbilicus using preoperative computed tomography. A weak negative correlation was found between BMI and VAT% (CC = -0.313, p = .001). Multivariate analysis showed that VAT% had a stronger correlation to total and practical operative time than BMI (ß = 0.338 vs 0.267, ß = 0.311 vs 0.209, respectively) and was an independent predictor of blood loss. VAT% was an independent predictive marker prolonged for operative time and increased blood loss during lymphadenectomy. CONCLUSION: VAT% could be an indicator of surgical outcomes for patients with obesity and endometrial cancer.

Precursor Radiographic Findings in Patients With Medication-Related Osteonecrosis of the Jaw.

BACKGROUND: Oral surgical treatment, such as tooth extraction, has been identified as a risk factor for the onset of medication-related osteonecrosis of the jaw (MRONJ). However, MRONJ may already be latent, and its manifestation may be triggered by extraction. PURPOSE: The purpose of this study was to examine the association between pre-extraction imaging and MRONJ. STUDY DESIGN, SETTING, SAMPLE: We performed a multicenter case-control analysis of patients receiving antiresorptive agents (ARAs) who underwent extraction between 2012 and 2016. We enrolled patients who had undergone tooth extraction in the setting of ARA exposure. PREDICTOR VARIABLES: The predictor variables comprised preoperative radiographic findings associated with MRONJ stage 0. These findings included alveolar bone loss, thickening or obscuring of the periodontal ligament, and osteosclerosis involving the alveolar bone. They were coded as present or absent before tooth extraction. MAIN OUTCOME VARIABLE: The primary outcome variable was MRONJ status coded as present or absent. COVARIATES: Sex, age, underlying diseases necessitating the administration of ARA, the type of ARA used, corticosteroid use, extraction region, and wound closure were analyzed. ANALYSES: Mann-Whitney U test, χ2 test, Fisher's exact test for univariate analysis, and multiple logistic regression analysis were performed. P values < .05 were significant. RESULTS: The subjects consisted of 26 patients and 110 controls (male: 8/36, female: 18/74). The mean ages of the MRONJ group and the control group were 77.0 ± 11.9 and 63.0 ± 15.8, respectively (P value = .001). The prevalence of osteosclerosis was significantly higher in the MRONJ group than in the control group (14/72, 53.9%/29.3%, P < .01). Multivariate analysis identified osteosclerosis (odds ratio: 8.4, 95% confidence interval: 2.133.9, P < .01) as a significant independent predictor associated with the development of MRONJ after extraction. CONCLUSION AND RELEVANCE: These findings suggest that a precursor to MRONJ is highly likely to be present in patients with osteosclerosis at the time of extraction. The majority of patients who developed MRONJ after extraction had imaging findings that suggested infection in the surrounding alveolar bone.

Effect of the Sauvé-Kapandji method on the wrist contact surface for distal radial ulnar joint disorders.

BACKGROUND: The Sauvé-Kapandji (S-K) method is a surgical procedure performed for chronic deformities of the distal radial ulnar joint (DRUJ). Changes to the joint contact surface from pre- to postoperatively under physiological in vivo conditions have not yet been determined for this useful treatment. The aim of the present study was therefore to compare the articular contact area of the wrist joint between before and after the S-K method for DRUJ disorders. METHODS: The SK method was performed for 15 patients with DRUJ osteoarthritis and ulnar impaction syndrome. We calculated the Mayo Wrist Score as the patient's clinical findings and created 3-dimensional bone models of cases in which the S-K method was performed and calculated the contact area and shift in the center of the contact area using customized software. RESULTS: The Mean modified Mayo Wrist Score improved significantly from 60.3 preoperatively to 80.3 postoperatively (P < 0.01). Scaphoid contact area to the radius increased significantly from 112.6 ± 37.0 mm2 preoperatively to 127.5 ± 27.8 mm2 postoperatively (P = 0.03). Lunate contact area to radius-ulna was 121.3 ± 43.3 mm2 preoperatively and 112.5 ± 37.6 mm2 postoperatively, but this decrease was not significant (P = 0.38). Contact area ratio of scaphoid to lunate increased significantly from 1.01 ± 0.4 preoperatively to 1.20 ± 0.3 postoperatively (P = 0.02). Postoperative translations of the center of the scaphoid and lunate contact areas were decomposed into ulnar and proximal directions. Ulnar and proximal translation distances of the scaphoid contact area were 0.8 ± 1.7 mm and 0.4 ± 0.6 mm, respectively, and those of the lunate contact area were 1.1 ± 1.7 mm and 0.4 ± 1.1 mm, respectively. This study revealed changes in wrist contact area and center of the contact area before and after the S-K method. CONCLUSION: These results may accurately indicate changes in wrist joint contact area from pre- to postoperatively using the S-K method for patients with DRUJ disorder. Evaluation of changes in contact area due to bone surface modeling of the wrist joint using 3DCT images may be useful in considering surgical methods.

Improvement of absorbability, osteoconductivity, and strength of a ß-tricalcium phosphate spacer for opening wedge high tibial osteotomy: clinical evaluations with 106 patients.

BACKGROUND: An ideal synthetic spacer for medial opening wedge high tibial osteotomy (MOWHTO) has not yet been developed. The authors have developed a new ß-tricalcium phosphate (ß-TCP) spacer with 60% porosity (N-CP60) by modifying the micro- and macro-pore structures of a conventional ß-TCP spacer (CP60) that is widely used in clinical practice. The purpose of this study was to compare the absorbability, osteoconductivity, and in vivo strength of the N-CP60 spacer with those of the CP60 spacer, when used in MOWHTO. METHODS: First, the porosity, diameter distribution of macro- and micropores, and compressive strength of each ß-TCP block were examined using methodology of biomaterial science. Secondly, a clinical study was performed using a total of 106 patients (106 knees) with MOWHTO, who were followed up for 18 months after surgery. In these knees, the N-CP60 and CP-60 spacers were implanted into 49 tibias and 57 tibias, respectively. The absorbability and osteoconductivity were radiologically evaluated by measuring the area of the implanted spacer remaining unabsorbed and assessing with the Hemert's score, respectively. The incidence of cracking in the implanted spacers was determined using computed radiography. Statistical comparisons were made with non-parametric tests. The significance level was set at p = 0.05. RESULTS: The N-CP60 and CP60 blocks had almost the same porosity (mean, 61.0% and 58.7%, respectively). The diameter of macropores was significantly larger (p < 0.0001) in the N-CP60 block than in the CP60 block, while the diameter of micropores was significantly smaller (p = 0.019) in the N-CP60 block. The ultimate strength of the N-CP60 block (median, 36.8 MPa) was significantly greater (p < 0.01) than that of the CP60 block (31.6 MPa). As for the clinical evaluations, the absorption rate of the N-CP60 spacer at 18 months after implantation (mean, 48.0%) was significantly greater (p < 0.001) than that of the CP60 spacer (29.0%). The osteoconductivity of the N-CP60 spacer was slightly but significantly higher (p = 0.0408) than that of the CP60 spacer only in zone 1. The incidence of in vivo cracking of the posteriorly located N-CP60 spacer at one month (mean, 75.5%) was significantly lower (p = 0.0035) than that of the CP60 spacer (91.2%). CONCLUSIONS: The absorbability, osteoconductivity, and compressive strength of the new N-CP60 spacer were significantly improved by modifying the macro- and micro-pore structures, compared with the conventional CP60 spacer. The N-CP60 spacer is more clinically useful than the CP60 spacer. TRIAL REGISTRATION NUMBER: H29-0002.

The efficacy of vaginal treatment for non-Lactobacillus dominant endometrial microbiota-A case-control study.

AIM: Reduced Lactobacillus occupancy in the uterine microflora has been associated with implantation failure. This study aimed to evaluate a treatment for improving the uterine microflora. METHODS: This study included patients diagnosed with repeated implantation failure-defined as failure to achieve pregnancy after two or more transfers of viable embryos-who were classified as non-Lactobacillus dominant. Treatment A comprised oral administration of antibiotics for 1 week, followed by oral probiotic butyrate tablets (3 g/day) for approximately 30 days. Treatment B comprised a 1-week course of oral (750 mg/day) and vaginal (250 mg/day) metronidazole, followed by a 1-week intravaginal administration of probiotic capsules (1 capsule/day) and continued oral administration of probiotics (1 capsule/day). Both treatments were compared in terms of efficacy in improving vaginal flora. Improvement was defined as Lactobacillus occupancy >90% or an increase in Lactobacillus occupancy >20%. RESULTS: Seven (41.2%) of 17 patients in the Treatment A group improved in response to the treatment. Contrastingly, 9 (90.0%) of 10 patients improved in the Treatment B group (p = 0.0127). Following treatment, Lactobacillus occupancy in the Treatment B group (62.9% ± 12.7%) was significantly higher than that in the Treatment A group (5.7% ± 9.8%) (p = 0.0242). CONCLUSIONS: This study demonstrates the effectiveness of combining antibiotics and probiotics in vaginal formulations for treating abnormal uterine microflora. However, its potential impact on in vitro fertilization outcomes remains unclear and warrants further investigation through larger, more comprehensive studies.

Safety and dose-finding trial of tadalafil administered for fetus in labor: A phase I clinical study.

AIM: This study aimed to investigate the safety and efficacy of tadalafil in protecting the fetus from hypoxic stress caused by repeated labor pains during delivery and preventing fetal hypoxic-ischemic encephalopathy. METHODS: The study used a three-case cohort approach. Three patients were administered 10 mg tadalafil and monitored for serious adverse events. In the absence of serious tadalafil-associated adverse events as assessed by the Safety Evaluation Committee, three new patients were added to the study and treated with 20 mg/dose. The blood levels of tadalafil were recorded before and after 2, 4, 8, and 12 h of administration and 2 h after delivery. RESULTS: A total of seven patients were enrolled, and after excluding one patient who delivered before 37 weeks, tadalafil was administered to six patients. Maternal adverse events were considered acceptable from the maternal perspective, with grade 1 headache, anorexia, and myalgia and no obstetrical complications after delivery at both doses. No serious neonatal adverse events were associated with tadalafil. Tadalafil blood levels remained stable at both doses. In addition, the level of soluble fms-like tyrosine kinase-1 did not alter, while that of the placental growth factor differed significantly before and after tadalafil administration. CONCLUSIONS: The study confirmed the safety of tadalafil administration during delivery for both mothers and newborns. The stable tadalafil blood levels confirmed the efficacy of the tested administration regime at 12 h interval. These findings would assist in conducting phase II trials to further verify the optimal dose and safety of tadalafil.

Higher association of articular surface destruction with rheumatoid forefoot deformity arising from dislocation of the metatarsophalangeal joints in the lateral column.

BACKGROUND: To evaluate the relationship between the pattern and severity of metatarsophalangeal (MTP) joint dislocation in the lesser toes and severity of joint destruction in rheumatoid forefoot deformities. METHODS: Participants comprised of 13 patients (16 feet) who underwent resection arthroplasty of the metatarsal head of the lesser toes for rheumatoid arthritis of the MTP joints. Correlations between preoperative radiographic findings and histological grades second to fifth metatarsal heads taken intraoperatively were analyzed. RESULTS: In 62 metatarsal heads, complete dislocation of the MTP joint in the lesser toes significantly resulted in severe joint destruction compared to mild or moderate dislocation (P < 0.05). The proportion of severe cartilage damage in MTP joints with complete dislocation was 100 % in the 5th MTP joint, 83.3 % in the 4th MTP joint, and 58.3 % in the 2nd and 3rd MTP joints. Moreover, complete dislocation of the MTP joints in the lateral column showed the most severe joint destruction compared to that in the medial column (P = 0.03). CONCLUSION: Complete dislocation of the MTP joint in the lateral column is related to joint destruction in rheumatoid forefoot deformities.

Radiation therapy improves survival in elderly patients with localized extremity soft tissue sarcoma.

BACKGROUND: This study aims to evaluate the efficacy of radiation therapy in enhancing survival outcomes among elderly patients diagnosed with localized extremity soft tissue sarcomas (STSs). Furthermore, it seeks to explore whether the survival benefits conferred by radiation therapy differ according to tumor characteristics and treatment modalities. METHODS: We conducted a retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database to identify patients aged 80 years and older diagnosed with localized extremity STSs. The study assessed 1498 eligible patients, analyzing cancer-specific survival (CSS) and overall survival (OS) through Kaplan-Meier survival analysis and Cox proportional hazards modeling. Propensity score matching was employed to adjust for potential confounders. RESULTS: Among the analyzed patients, 773 patients underwent radiation therapy (Radiation group), while 725 patients either did not receive radiation therapy or it was unknown if they had (No-Radiation group). The 5-year OS rate was 40% in the radiation group compared to 38% in the no-radiation group. After propensity score matching, radiation therapy was associated with a significant improvement in OS (P = 0.005, HR = 0.8, 95% CI 0.7-0.9). Subgroup analyses indicated that patients undergoing primary tumor resection benefited most from radiation therapy in terms of OS. CONCLUSION: Radiation therapy is associated with improved overall survival in elderly patients with localized extremity STSs. These findings suggest that radiation therapy should be considered as a key component of the treatment strategy for this patient population, taking into account individual patient characteristics and comorbidities.

The effectiveness of a self-reported questionnaire on masticatory function in health examinations.

Periodontal diseases have been reported to be lifestyle-related and associated with metabolic syndrome (MetS). The introduction of dental checkups in a health checkup program may create a synergistic effect and aid the prevention of MetS. In Japan, a chewing function questionnaire has now been introduced into the national health checkup program. The purpose of this study was to investigate whether the questionnaire reflects dental and oral conditions and whether it helps improve general and oral health. A total of 6599 subjects who underwent health checkups or guidance specified by the National Health Insurance of Japan for two consecutive years were included. A single comprehensive question to evaluate masticatory function was asked. Medical and dental examinations and insurance data were collected and used for analysis. In terms of masticatory function during chewing, 82.3% of subjects experienced no problems, 17.3% experienced some difficulty, and 0.4% experienced severe problems. There was a significant relationship between the questionnaire response and dental examinations results for several items of examination. The overall dental consultation rate after health screening was 42.3%. Improvement in periodontal disease was achieved in those who reported some problems with chewing function. Improvement in blood pressure was also observed in those who reported some problem with chewing function and subsequently had a dental consultation. The results of this study indicate that questionnaires on masticatory function reflect the status of dental and oral health. In addition, the results suggested that questionnaire results are potentially linked to improvement in dental and oral health status, and improvement in MetS.

Modes of delivery and indications in women with COVID-19: a regional observational study in Japan.

BACKGROUND: During the coronavirus disease (COVID-19) pandemic, caesarean section (CS) has been the preferred deliver method for pregnant women with COVID-19 in order to limit the use of hospital beds and prevent morbidity among healthcare workers. METHODS: To evaluate delivery methods used during the COVID-19 pandemic as well as the rates of adverse events and healthcare worker morbidity associated with caesarean deliveries. METHODS: We investigated maternal and neonatal backgrounds, delivery methods, indications and complication rates among pregnant women with COVID-19 from December 2020 to August 2022 in Mie Prefecture, Japan. The predominant mutation period was classified as the pre-Delta, Delta and Omicron epoch. RESULTS: Of the 1291 pregnant women with COVID-19, 59 delivered; 23 had a vaginal delivery and 36 underwent CS. Thirteen underwent CS with no medical indications other than mild COVID-19, all during the Omicron epoch. Neonatal complications occurred significantly more often in CS than in vaginal delivery. COVID-19 in healthcare workers was not attributable to the delivery process. CONCLUSION: The number of CS with no medical indications and neonatal complications related to CS increased during the COVID-19 pandemic. Although this study included centres that performed vaginal deliveries during COVID-19, there were no cases of COVID-19 in healthcare workers. It is possible that the number of CS and neonatal complications could have been reduced by establishing a system for vaginal delivery in pregnant women with recent-onset COVID-19, given that there were no cases of COVID-19 among the healthcare workers included in the study.

We evaluated the incidence of adverse events associated with caesarean section (CS) deliveries and the morbidity of health care workers, which increased during the coronavirus infection pandemic. Maternal and neonatal background, delivery methods, indications and complication rates of pregnant women with COVID-19 from December 2020 to August 2022 in Mie Prefecture were investigated by time of onset. Of the 1291 pregnant women with COVID-19, 59 delivered while affected; 23 underwent vaginal delivery and 36 CS. Of these, 13 who underwent CS in the omicron epoch had no medical indication other than mild COVID-19. Neonatal complications were significantly more common with CS than with vaginal delivery, and there was no occurrence of COVID-19 in healthcare workers. In this study, there were no cases of COVID-19 among health care workers; establishing a system to perform vaginal delivery for pregnant women with COVID-19 could have reduced the number of CS and neonatal complications.

Age, sexual abstinence duration, sperm morphology, and motility are predictors of sperm DNA fragmentation.

Purpose: Sperm DNA fragmentation (SDF) has recently received attention as a cause of male infertility. However, SDF cannot be fully assessed using conventional semen parameter evaluations alone. Therefore, the authors aimed to elucidate the relationship between SDF and sperm parameters via computer-assisted sperm analysis (CASA) to improve treatment strategies in reproductive medicine. Methods: This retrospective observational study analyzed the relationship between sperm parameters assessed by CASA and SDF values determined by the TUNEL assay in 359 patients who visited the Mie University Hospital for infertility treatment. The methodology involved semen analyses covering concentration, motility, and morphology, followed by SDF quantification using the flow cytometry. Results: Statistical analysis revealed significant correlations between SDF and various factors, including age, sexual abstinence period, and specific CASA-measured parameters. Notably, lower sperm motility rates and abnormal head dimensions were associated with higher SDF values, indicating that these parameters were predictive of SDF. Conclusions: This study highlights the importance of sperm motility and head morphology as indicators of SDF, suggesting their usefulness in assessing male fertility. These findings demonstrate the efficacy of detailed sperm analysis, potentially increasing the success rate of assisted reproductive technologies by improving sperm selection criteria.

Analysis of foot-originating malignant bone tumors: Epidemiology, characteristics, and survival outcomes.

BACKGROUND: The study examines the characteristics and outcomes of foot-originating malignant bone tumors via Surveillance Epidemiology and End Results (SEER) database analysis. METHODS: A retrospective review of 14,695 malignant bone tumor cases from 2000 to 2019 was conducted. RESULTS: Of the eligible cases, 147 (2.3 %) were foot-origin tumors, typically smaller and more commonly treated with surgery than those in other locations. These tumors were more frequently treated with surgical resection, with a higher proportion undergoing amputation. In contrast, foot-origin tumors were less often managed with chemotherapy and radiation. Foot-origin tumors exhibited higher survival rates compared to non-foot-origin tumors as shown in univariate analysis, although multivariate analysis did not reflect significant differences. CONCLUSION: Foot-originating malignant bone tumors tend to be smaller and are frequently surgically treated, correlating with favorable survival outcomes. These findings point to early detection as a potential factor in the improved survival rates, not necessarily the tumor's origin.

High-speed spinning of collagen microfibers comprising aligned fibrils for creating artificial tendons.

Bundles of engineered collagen microfibers are promising synthetic tendons as substitutes for autogenous grafts. The purpose of this study was to develop high-speed and continuous spinning of collagen microfibers that involves stretching of collagen stream. Our study revealed the 'critical fibrillogenesis concentration (CFC)' of neutralized collagen solutions, which is defined as the upper limit of the collagen concentration at which neutralized collagen molecules remain stable as long as they are cooled (⩽10 °C). Neutralized collagen solutions at collagen concentrations slightly below the CFC formed cord-like collagen gels comprising longitudinally aligned fibrils when extruded from nozzles into an ethanol bath. Dry collagen microfibers with a controlled diameter ranging from 122 ± 2-31.2 ± 1.7 µm can be spun from the cord-like gels using nozzles of various sizes. The spinning process was improved by including stretching of collagen stream to further reduce diameter and increase linear velocity. We extruded a collagen solution through a 182 µm diameter nozzle while simultaneously stretching it in an ethanol bath during gelation and fiber formation. This process resembles the stretching of a melted thermoplastic resin because it solidifies during melt spinning. The mechanical properties of the stretched collagen microfibers were comparable to the highest literature values obtained using microfluidic wet spinning, as they exhibited longitudinally aligned fibrils both on their surface and in their core. Previous wet spinning methods were unable to generate collagen microfibers with a consistent tendon-like fibrillar arrangement throughout the samples. Although the tangent modulus (137 ± 7 MPa) and stress at break of the swollen bundles of stretched microfibers (13.8 ± 1.9 MPa) were lower than those of human anterior cruciate ligament, they were within the same order of magnitude. We developed a spinning technique that produces narrow collagen microfibers with a tendon-like arrangement that can serve as artificial fiber units for collagen-based synthetic tendons.

Screening of aspiration pneumonia using the modified Mallampati classification tool in older adults.

Pneumonia is a major cause of morbidity and mortality in older adults. In the aging society, screening methods for predicting aspiration pneumonia are crucial for its prevention. Changes in the oropharyngeal morphology and hyoid bone position may increase the risk of aspiration pneumonia. This multicenter study aimed to investigate a simple and effective screening method for predicting dysphagia and aspiration pneumonia. Overall, 191 older adults (aged 65 years or older) were randomly sampled using the simple random sampling technique. Oropharyngeal morphology was assessed using the modified Mallampati classification, which reflects the size of the tongue in the oropharyngeal cavity. The hyoid position was measured as the distance between the menton and laryngeal prominence to evaluate aging-related changes in the muscles of the laryngopharynx. Dysphagia was assessed using the repetitive saliva swallowing test (RSST), which measures the number of swallowing movements in 30 seconds; dysphasia is defined as less than 3 swallowing movements in 30 seconds. The aspiration signs were assessed based on history of choking or coughing reflex during eating or drinking and medical history of pneumonia. The study findings revealed that the modified Mallampati classification was significantly correlated with a medical history of pneumonia. A higher incidence of pneumonia was evident in the lower Mallampati classification, which shows the smaller size of the tongue base in the oropharyngeal cavity. The results of this study suggest that the modified Mallampati classification may be a possible screening method to predict the occurrence of pneumonia.

The alterations in nerve growth factor concentration in plasma and synovial fluid before and after total knee arthroplasty.

Total knee arthroplasty (TKA) is an effective procedure for pain relief; however, the emergence of postsurgical pain remains a concern. In this study, we investigated the production of nerve growth factor (NGF) and mediators that affect NGF production and their function in the synovial fluid and plasma after TKA. This study included 19 patients (20 knees) who had rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and knee osteoarthritis (OA) who underwent TKA, categorized into OA and non-OA groups. The levels of NGF, inflammatory cytokines, and lipid mediators were analyzed before and after surgery. The intraoperative synovial fluid NGF concentration was more than seven times higher in the non-OA group than in the OA group. The intra-articular NGF levels increased significantly by more than threefold postoperatively in the OA group but not in the non-OA group. Moreover, the levels of inflammatory cytokines and lipid mediators were increased in the synovial fluid of both groups. The intra-articular cytokines or NGF concentrations positively correlated with postoperative pain. Targeted NGF control has the potential to alleviate postsurgical pain in TKA, especially in patients with OA, emphasizing the importance of understanding NGF dynamics under different knee conditions.

Dental and oral management in the perioperative period of surgery: A scoping review.

Dental and oral management (DOM) is a long-established treatment modality. This scoping review aimed to narratively review previous studies, examine the effects of perioperative DOM, and identify the available evidence. A literature search was conducted using the PubMed electronic database for studies published between January 1, 2000, and March 8, 2022. The search yielded 43 studies, most of which were published in the last 10 years. The results of this study confirmed that improved perioperative oral hygiene is effective in preventing postoperative pneumonia. Our results also suggested that preoperative DOM is effective in preventing postoperative surgical site infections. Perioperative DOM is effective in reducing the incidence of postoperative pneumonia, SSI, and postsurgical complications. Further studies are needed to elucidate the various mechanism of DOM and to examine efficient intervention methods and timing.

Elucidation of the association between additional distal femoral resection and extension angle improvement following the actual surgical steps with the Robot-TKA system.

BACKGROUND: This study investigates the association between additional distal femoral resection and improved flexion contracture in total knee arthroplasty (TKA) with a robot-assisted system. Flexion contracture is a common issue in patients with knee osteoarthritis, which causes postoperative complications and functional limitations. This study aims to evaluate the effectiveness of additional bone resection in flexion contracture correction and knee extension angle improvement after the actual surgical steps. METHODS: The study included 11 patients who underwent posterior-stabilized (PS)-type TKA with a robot-assisted system. The surgical technique consisted of precise bone resection and range of motion evaluation using a navigation system. A precut technique was used to facilitate posterior access and remove osteophytes that cause the contracture. The amount of additional distal femoral resection was determined based on the thickness of the insert trial required for achieving full extension. RESULTS: The flexion contracture correction angle and the amount of additional distal femoral resection demonstrated a linear relationship. An average of 2.0° with the standard error (SE) of 0.6° improvement in flexion contracture was observed per 1.0 mm of additional bone resection. The postoperative evaluation demonstrated a significant improvement in knee extension angle, thereby reducing the contracture degree. CONCLUSION: This study was the first to perform the additional distal femoral resection on the living knee, which closely replicates the actual surgical steps. The current study revealed that an additional 1.0 mm of distal femoral resection in PS-type TKA improves knee extension angle by 2.0° (SE 0.6°) within an additional resection range of 1.0 mm to 3.3 mm.

Paradoxical Change in Subchondral Bone Density in the Medial Compartment of the Proximal Tibial Articular Surface After High Tibial Osteotomy: A Detailed Subchondral Bone Density Analysis.

BACKGROUND: High tibial osteotomy (HTO) aims to realign the varus knee to alleviate stress in the medial compartment. However, detailed information on the impact of HTO on stress distribution across the tibiofemoral joint surface still needs to be completely elucidated. PURPOSE/HYPOTHESIS: The present study aimed to analyze the subchondral bone density distribution to validate the alignment threshold causing paradoxical changes. We hypothesized that there would be a paradoxical stress change in the medial compartment beyond a specific threshold for lower limb realignment after HTO. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective clinical study of 32 knees from 30 patients who underwent medial opening-wedge HTO between 2015 and 2019 was conducted at Hokkaido University Hospital. The subchondral bone density across the tibiofemoral joint was analyzed using computed tomography-osteoabsorptiometry before and after HTO. The high-density area (HDA) within the medial and lateral compartments and their subregions, which were quartered in the coronal plane, was specifically examined. RESULTS: The hip-knee-ankle angle, medial proximal tibial angle (MPTA), joint line obliquity (JLO), and joint line convergence angle significantly changed after HTO (P < .01). The HDA of the medial compartment to the total HDA ratio decreased from 83% to 77%. Paradoxically, the HDA in the most central subregion of the medial compartment increased from 24% to 30%. There were significant differences between MPTA and JLO in patients with and without paradoxical changes in the HDA. MPTA and JLO cutoff values causing paradoxical changes in the HDA were 94° and 4°, respectively. CONCLUSION: There was a paradoxical stress increase in the M4 region at the medial compartment associated with the MPTA and JLO beyond specific thresholds. Therefore, surgical planning should be cautiously performed to prevent overcorrection, which can lead to adverse stress distribution changes.

Surgical Resection of Primary Tumor for Bone Metastatic Breast Cancer Patients at Initial Presentation.

BACKGROUND/AIM: The purpose of this study was to investigate whether primary tumor resection in patients with bone metastatic breast cancer has an impact on survival using the Surveillance, Epidemiology, and End Results database, considering subtype classification. PATIENTS AND METHODS: We included all female patients with bone metastatic breast cancer at initial presentation between 2010 and 2016 with known hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) statuses. Cases showing unknown cause of death or unknown HR/HER2 status were excluded. Survival analysis was performed using Cox proportional hazards modeling to calculate hazard ratios (HZR). RESULTS: Of the 13,450 patients included in this study, 2,073 patients were HR+/HER2+, 8,597 patients were HR+/HER2-, 797 patients were HR-/HER2+, and 1,182 patients were HR-/HER2- (triple-negative). Five-year overall survival (OS) rate was 34.5% in HR+/HER2+, 26.0% in HR+/HER2-, 29.2% in HR-/HER2+ and 8.0% in triple-negative. Triple-negative patients showed the worsen OS [HR+/HER2+: HZR=2.1, 95% confidence interval (CI)=1.9-2.3; HR+/HER2-: HZR= 2.4, 95%CI=2.2-2.6; HR-/HER2+: HZR=1.5, 95%CI=1.3-1.6]. After excluding patients who died within six months, primary tumor resection prolonged survival in each subtype classification except HR-/HER2+. CONCLUSION: Patients with triple-negative bone metastatic breast cancer showed unfavorable survival. Primary tumor resection prolonged survival in each subtype except for HR-/HER2+.