Clinicopathologic Features of Adult-onset Still's Disease Complicated by Severe Liver Injury.

Adult-onset Still's disease (AOSD) is a systemic inflammatory disorder. Severe liver injury has rarely been reported, although liver enzyme elevation is a common complication of AOSD. We herein report four cases of relapsed AOSD with severe liver disorder by tapering or terminating corticosteroids. Liver specimens revealed robust infiltration of inflammatory cells throughout the lobule, especially cluster of differentiation (CD) 8-positive cells. Relapsed AOSD was refractory to corticosteroid reintroduction and required immunosuppressants. Severe liver injury with AOSD is pathologically characterized by extensive lobular infiltration of CD8-positive cells, and we should consider additive immunosuppressive agents on corticosteroids for treatment.

Acute kidney injury is an unfavorable prognostic factor in acute liver failure and is associated with tumor necrosis factor-alpha.

Acute kidney injury (AKI) is a common complication of acute liver failure (ALF); but its pathogenesis is unknown. ALF was divided into 2 subgroups; ALF with hepatic coma, which corresponds to ALF in the US and Europe, and ALF without hepatic coma. AKI has been shown to worsen the prognosis of ALF patients with hepatic coma; however, its prognostic significance in ALF without hepatic coma remains unknown. A single-center retrospective study of 174 patients with ALF was performed. AKI was defined according to KDIGO criteria. AKI developed in 29 (66.0%) of 44 ALF patients with hepatic coma and 27 (38.5%) of 130 ALF patients without hepatic coma. Systemic inflammatory response syndrome (SIRS) was found to be significantly associated with AKI incidence in ALF patients (P < .001). Tumor necrosis factor-alpha (TNF-α) was found to be significantly associated with the presence and severity of AKI (P = .0039 and P = .0140, respectively). On multivariate analysis, TNF-α was an independent risk factor linked with AKI (P = .0103). Even in the absence of hepatic coma, the transplant-free survival rate of ALF was significantly associated with the presence and severity of AKI. Even when hepatic coma is absent, AKI complicated in ALF is strongly associated with TNF-α and worsens the transplant-free survival rate. Before the onset of hepatic coma, plasma exchange, or extracorporeal blood purification to remove inflammatory cytokines should be considered in ALF patients.

Autologous Osteochondral Grafts for Knee Osteochondral Diseases Result in Good Patient-Reported Outcomes in Patients Older Than 60 Years.

Purpose: This study aims to examine the clinical autologous osteochondral grafts (AOG) outcomes for knee osteochondral diseases at operative ages >60 years, and to determine whether patients are able to sit straight in Japanese style after AOG. Methods: All patients who underwent AOG for knee osteochondral diseases between November 2001 and April 2018 were retrospectively identified. The inclusion criteria were AOG only without osteotomy, operative ages between 60 and 79 years, >2 years of follow-up, and involved femorotibial angle between 169° and 179° (normal alignment). Patients who underwent osteotomy to improve knee alignment and patients with inflammatory diseases such as rheumatoid arthritis were excluded. The patients' knee symptoms and their clinical outcome were evaluated according to the criteria of the knee scoring system of the Japanese Orthopedic Association (JOA), International Knee Documentation Committee (IKDC) subjective score, and the ability of straight sitting in Japanese style. Results: This study enrolled 57 cases and 60 knee joints during the study period. The follow-up ratio was 85.1%. Moreover, 14 men and 43 women and 29 right and 31 left knee joints were included in this study. The mean operative age and mean follow-up period were 67.8 years (range 60-76 years) and 81.1 months (range 24-167 months), respectively. In addition, the study involved 30 cases and 32 knee joints (60s group), and 27 cases and 28 knee joints (70s group). Moreover, 34 cases and 36 knee joints had osteonecrosis (ON group), and 23 cases and 24 knee joints had cartilage injury (CI group). The IKDC subjective and JOA scores in both the 60s and 70s groups showed significant differences: 2 years after AOG ＞at the follow-up period, ＞at the preoperative period. The scores in both the CI and ON groups showed similar significant differences. Furthermore, 8.3% and 53.5% of the patients could sit straight in Japanese style at the preoperative period and 2 years after AOG, respectively. Conclusion: Even if the patient's operative age was >60 years, the AOG only for their knee osteochondral diseases had good clinical outcomes, including the ability to sit straight in Japanese style. Level of Evidence: IV, Therapeutic case series Key words: autologous osteochondral grafts, aged patients, clinical outcome, knee joint, straight sitting in Japanese style.

Preoperative diagnosis of knee cartilage, meniscal, and ligament injuries by magnetic resonance imaging.

PURPOSE: The purpose of the study was to report on the current accuracy measures specific to 1.5-Tesla MRI of the knee in the patient population prone to injuries of the anterior cruciate ligament (ACL), the menisci, and the articular cartilage. METHODS: We accrued patients between January 2018 through August 2021 who underwent a preoperative MRI and were diagnosed with an articular cartilage injury either due to unevenness of articular cartilage in T2-weighted sequences or due to the irregularity of subchondral bone in T1-weighted sequences. All patients were treated arthroscopically. Sensitivity, specificity, and accuracy were calculated for the detection of ACL, meniscus, and cartilage injuries. A P-value of < 0.05 represented statistical significance. RESULTS: One-hundred and forty-seven cases which included 150 knee joints were enrolled in this study. The mean age at the time of surgery was 42.9 years-old. The sensitivity in the diagnosis of ACL injuries was significantly greater than that in the diagnosis of cartilage injuries (P = 0.0083). The ratios of the equality of operative indication in 6 recipient sites were found to be between 90.0% and 96.0%. The diagnostic critical point was within a 1 cm in diameter. CONCLUSION: The diagnostic sensitivity in cartilage injuries was significantly lower than ones of ACL and meniscal injuries. The ratios of the equality of operative indication was determined to be between 90.0% and 96.0%, if we consider the unevenness of articular cartilage or the irregularity of subchondral bone. LEVEL OF EVIDENCE: Level III, Prospective diagnostic cohort study.

Transcatheter arterial steroid injection therapy improves the prognosis of patients with acute liver failure.

Acute liver failure (ALF) is a disorder defined by coagulopathy and encephalopathy with a poor prognosis. No effective therapies have been established except for liver transplantation. We previously reported a subgroup of patients with acute liver injury who developed microcirculatory disturbance. We also established and reported transcatheter arterial steroid injection therapy (TASIT) as a new treatment of ALF. Here, we analyze the effectiveness of TASIT in a larger cohort and evaluate the impact on ALF patients with or without microcirculatory disturbance. We conducted a single-center retrospective study to evaluate the effectiveness of TASIT in patients with ALF admitted at Kyushu University Hospital between January 2005 and March 2018. TASIT is performed by injecting methylprednisolone via the proper hepatic artery for 3 days. One hundred ninety-4 patients with ALF were enrolled and analyzed in this study. Of the 87 patients given TASIT, 71 (81.6%) recovered without any complications and 16 (18.4%) died or underwent liver transplantation. Of the 107 patients not administered TASIT, 77 (72.0%) recovered and 30 (28.0%) progressed to irreversible liver failure. In the high-lactate dehydrogenase subgroup, 52 (86.7%) of the 60 patients with TASIT recovered, and the survival rate was significantly higher than that in patients who did not receive TASIT. Multivariate regression analysis revealed that the TASIT procedure was one of the significant prognostic factors in the high-lactate dehydrogenase subgroup and was significantly associated with prothrombin activity percentage improvement. TASIT is an effective treatment for patients with ALF, especially in those with microcirculatory disturbance.

Intraoperative Acoustic Evaluation of Living Human Knee Cartilage-Comparison with Respect to Cartilage Degeneration and Aging.

OBJECTIVE: The objective of the study was to evaluate the mechanical properties of living human knee cartilage using our ultrasonic device, and to compare the measurements with respect to cartilage degeneration and aging. DESIGN: A total of 95 knees which had undergone arthroscopic knee surgery, from 88 patients, were included in the study, with informed consent. All procedures were reviewed and approved by the ethical committee of our hospital. In the study group, there were 41 men, 47 women, 39 right knees, and 56 left knees. The conditions primarily included knee osteoarthritis and anterior cruciate ligament rupture. The mean operative age was 44.1 years old (range = 10-83). We compared mechanical properties of the knee cartilage with respect to aging and gender, in comparison with normal cartilage. A P value of <0.05 represented statistical significance. RESULTS: In the context of the International Cartilage Repair Society (ICRS) classification of cartilage degeneration (grade 0-3), the signal intensity in grade 0 was significantly larger than that in grade 1, 2, or 3. The thickness in grade 0 was significantly higher than that in grade 1, 2, or 3. Normal cartilage in older women had the lowest signal intensity and the least cartilage thickness among all the groups. CONCLUSION: The ultrasonic system we developed was able to detect early degenerative changes in living cartilage in knees. The lowest signal intensity and least cartilage thickness in normal cartilage among older women were correlated to a large prevalence of knee osteoarthritis in women. LEVEL OF EVIDENCE: Level IV, case series.

Mosaicplasty With High Tibial Osteotomy for Knee Subchondral Insufficiency Fracture Had Better Magnetic Resonance Observation of Cartilage Repair Tissue Scores With Less Bone Marrow Edema and Better Plug Union and Less Plug Necrosis Compared With Mosaicplasty Alone.

PURPOSE: To determine the magnetic resonance imaging (MRI) findings after mosaicplasty (MOS) for knee subchondral insufficiency fracture (SIFK), and to analyze the relationship between MRI findings and clinical outcomes. METHODS: We retrospectively reviewed the cases of consecutive patients who underwent MOS for SIFK with/without high tibial osteotomy (HTO) between January 1998 and December 2015. The MRI findings at 12 months after the surgery were assessed by the modified magnetic resonance observation of cartilage repair tissue (MOCART) score to determine the degree of bone marrow edema (BME), plug union, and plug necrosis. The clinical outcomes were assessed by Lysholm score to clarify the minimal clinically important difference (MCID) and patient acceptable symptom state analysis. RESULTS: In total, 58 patients (17 men and 41 women) were enrolled in this study. Among them, 30 knees were treated by MOS alone and 28 knees were treated by MOS with HTO. The MOCART scores of patients who received MOS alone were significantly lower in BME score (P = .0060), plug union score (P = .0216), and in plug necrosis score (P = .0326) than patients who received MOS with HTO. BME lesion was less likely to persist among elderly (odds ratio 1.20, P = .0248) and female (OR 41.8, P = .0118) patients. The MCID of Lysholm score was 6.6 in MOS alone and 8.4 in MOS with HTO cases, but there were no significant association between MRI findings and the postoperative Lysholm score. CONCLUSIONS: The MOS with HTO cases had better MOCART scores with less BME, better plug union, and less plug necrosis compared with MOS alone cases. Female and older patients had better resolution of BME, but there was no significant correlation between MRI findings and the postoperative Lysholm score. All cases in both groups showed improvement of Lysholm score exceeding MCID; thus, MOS may be effective as a joint preserving surgery for SIFK. LEVEL OF EVIDENCE: Level IV, clinical case series.

Corticosteroid suppresses urea-cycle-related gene expressions in ornithine transcarbamylase deficiency.

BACKGROUND: Ornithine transcarbamylase deficiency (OTCD) is most common among urea cycle disorders (UCDs), defined by defects in enzymes associated with ureagenesis. Corticosteroid administration to UCD patients, including OTCD patients, is suggested to be avoided, as it may induce life-threatening hyperammonemia. The mechanism has been considered nitrogen overload due to the catabolic effect of corticosteroids; however, the pathophysiological process is unclear. METHODS: To elucidate the mechanism of hyperammonemia induced by corticosteroid administration in OTCD patients, we analyzed a mouse model by administering corticosteroids to OTCspf-ash mice deficient in the OTC gene. Dexamethasone (DEX; 20 mg/kg) was administered to the OTCspf-ash and wild-type (WT) mice at 0 and 24 h, and the serum ammonia concentrations, the levels of the hepatic metabolites, and the gene expressions related with ammonia metabolism in the livers and muscles were analyzed. RESULTS: The ammonia levels in Otcspf-ash mice that were administered DEX tended to increase at 24 h and increased significantly at 48 h. The metabolomic analysis showed that the levels of citrulline, arginine, and ornithine did not differ significantly between Otcspf-ash mice that were administered DEX and normal saline; however, the level of aspartate was increased drastically in Otcspf-ash mice owing to DEX administration (P < 0.01). Among the enzymes associated with the urea cycle, mRNA expressions of carbamoyl-phosphate synthase 1, ornithine transcarbamylase, arginosuccinate synthase 1, and arginosuccinate lyase in the livers were significantly downregulated by DEX administration in both the Otcspf-ash and WT mice (P < 0.01). Among the enzymes associated with catabolism, mRNA expression of Muscle RING-finger protein-1 in the muscles was significantly upregulated in the muscles of WT mice by DEX administration (P < 0.05). CONCLUSIONS: We elucidated that corticosteroid administration induced hyperammonemia in Otcspf-ash mice by not only muscle catabolism but also suppressing urea-cycle-related gene expressions. Since the urea cycle intermediate amino acids, such as arginine, might not be effective because of the suppressed expression of urea-cycle-related genes by corticosteroid administration, we should consider an early intervention by renal replacement therapy in cases of UCD patients induced by corticosteroids to avoid brain injuries or fatal outcomes.

Do radiological findings around the Fitmore stem change over time? : radiolucency around the short hip stem disappears within a few years: a retrospective study.

AIMS: Although the short stem concept in hip arthroplasty procedure shows acceptable clinical performance, we sometimes get unexplainable radiological findings. The aim of this retrospective study was to evaluate changes of radiological findings up to three years postoperatively, and to assess any potential contributing factors on such radiological change in a Japanese population. METHODS: This is a retrospective radiological study conducted in Japan. Radiological assessment was done in accordance with predetermined radiological review protocol. A total of 241 hips were included in the study and 118 hips (49.0%) revealed radiological change from immediately after surgery to one year postoperatively; these 118 hips were eligible for further analyses. Each investigator screened whether either radiolucent lines (RLLs), cortical hypertrophy (CH), or atrophy (AT) appeared or not on the one-year radiograph. Further, three-year radiographs of eligible cases were reviewed to determine changes such as, disappeared (D), improved (I), stable (S), and progression (P). Additionally, bone condensation (BC) was assessed on the three-year radiograph. RESULTS: CH was observed in 49 hips (21.1%), AT was observed in 63 hips (27.2%), and RLLs were observed in 34 hips (14.7%) at one year postoperatively. Among 34 hips with RLLs, 70.6% showed change of either D or I on the three-year radiograph. BC was observed in younger patients more frequently. CONCLUSION: The Fitmore stem works well in a Japanese population with favourable radiological change on hips with RLLs. Longer-term follow-up is required to determine clinical relevance. Cite this article: Bone Jt Open 2022;3(1):20-28.

Pirfenidone attenuates acetaminophen-induced liver injury via suppressing c-Jun N-terminal kinase phosphorylation.

Acetaminophen (APAP)-induced liver injury is the most frequent cause of acute liver failure in Western countries. Pirfenidone (PFD), an orally bioavailable pyridone derivative, is clinically used for idiopathic pulmonary fibrosis treatment and has antifibrotic, anti-inflammatory, and antioxidant effects. Here we examined the PFD effect on APAP-induced liver injury. In a murine model, APAP caused serum alanine aminotransferase elevation attenuated by PFD treatment. We performed terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) and vital propidium iodide (PI) stainings simultaneously. APAP induced TUNEL-positive/PI-negative necrosis around the central vein and subsequent TUNEL-negative/PI-positive oncotic necrosis with hemorrhage and caused the upregulation of hypercoagulation- and hypoxia-associated gene expressions. PFD treatment suppressed these findings. Western blotting revealed PFD suppressed APAP-induced c-Jun N-terminal kinase (JNK) phosphorylation despite no effect on JNK phosphatase expressions. In conclusion, simultaneous TUNEL and vital PI staining is useful for discriminating APAP-induced necrosis from typical oncotic necrosis. Our results indicated that PFD attenuated APAP-induced liver injury by suppressing TUNEL-positive necrosis by directly blocking JNK phosphorylation. PFD is promising as a new option to prevent APAP-induced liver injury.

Clinical and primary evidence of silver diamine fluoride on root caries management.

Root caries is a growing problem for the worldwide aging population. Silver diamine fluoride (SDF) contains high concentrations of silver and fluoride ions, which prevents and arrests root caries, as well as dentin caries in the primary teeth of young children. Unlike other fluoride products that mainly reduce the formation of new carious lesions, 38% SDF is an effective agent that can efficiently arrest the carious process, remineralize the decayed dental tissues, and protect the tooth structure against the formation of new caries lesions. The use of SDF can result in more caries-resistant tooth structures. Despite these merits, its clinical disadvantages are the deep penetration of silver ions and sequential formation of silver compounds, which cause esthetic concern due to the discoloration and impaired efficacy of dentin bonding after using SDF. Thus, this narrative review, by addressing the primary experimental results and clinical applications of SDF on root caries, proposes management methods for root caries in conjunction with the application of SDF. We propose a two-visit treatment protocol to take advantage of the SDF application for root surface caries and utilize the discoloration caused by SDF.

Micro-CT assessment of the effect of silver diammine fluoride on inhibition of root dentin demineralization.

This study evaluated the ability of different types of silver diammine fluoride (SDF) to inhibit dentin demineralization using micro-focused X-ray computed-tomography (µCT). Dentin specimens were divided into five groups (n=10); no-treatment (control), 3.8% SDF (RC), 38% SDF, 38% SDF with potassium iodide (SDF/KI), and potassium fluoride (KF). The treated-dentin surfaces were subjected to demineralization for 7-days and assessed using µCT to determine mineral loss (ML) values. Specimens were also analyzed with scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The ML values of the SDF and KF groups were significantly lower than those of the RC and SDF/KI groups. EDS detected fluoride ions in the SDF and KF groups but not in the RC and SDF/KI groups. It was concluded that 38% SDF demonstrated a high ability to inhibit dentin demineralization while additional application of KI may diminish the inhibitory effect of SDF. The amount of dentin demineralization with SDF treatments was material dependent.

Effects of silver diamine fluoride preparations on biofilm formation of Streptococcus mutans.

Effects of silver diamine fluoride preparations (SDFs) on cariogenic biofilm formation on root dentin (RD) were investigated. Streptococcus mutans (S. mutans) biofilms were formed on bovine RD blocks coated with one of three the SDFs (38%-SDF, 3.8%-SDF and 35%-SDF+potassium-iodide; SDF+KI) and a non-coated Control which were quantified (spectrometric-measurement) and thickness measured (optical coherence tomography) after 20 h. Bacterial viability test (BacLight) and biofilm-morphometry (SEM) of 2 h biofilms were also performed. The amounts of biofilms (bacteria and water insoluble glucan) and the thickness of biofilm were minimum on 38%-SDF specimen; 3.8%-SDF and SDF+KI had significantly more than that, but had significantly less than Control (p<0.05). Most S. mutans cells found dead and morphology damaged by 38%-SDF. Some dead bacteria and remarkably damaged biofilms were observed in case of 3.8%-SDF and SDF+KI. Inhibition potential of 3.8%-SDF and SDF+KI on S. mutans biofilm formation is almost similar, although not equivalent to 38%-SDF.

Metabolic Alteration in Hepatocellular Carcinoma: Mechanism of Lipid Accumulation in Well-Differentiated Hepatocellular Carcinoma.

Objective: Metabolic alteration is widely considered as one of the hallmarks of cancer. Hepatocellular carcinoma (HCC) presents a unique pathological feature in which lipid accumulation is common in well-differentiated HCC and rare in poorly differentiated HCC; however, the underlying mechanism remains unclear. Methods: Tissue samples were obtained from 103 HCC patients who had undergone hepatic resection and 12 living donors of liver transplantation. We evaluated metabolic gene expressions in cancer tissues as well as background noncancer tissues and compared the expressions by the degree of cancer differentiation and by liver disease states. Besides, the metabolomics was evaluated and integrated to gene expressions in nonalcoholic steatohepatitis (NASH)-HCC model mice. Results: In cancer tissues, the expression levels of enzymes related to glycolysis, pentose phosphate pathway (PPP), and fatty acid (FA) synthesis were increased and that of tricarboxylic acid (TCA) cycle and ß-oxidation were suppressed. Same metabolic alterations were observed in noncancer tissue as the liver disease progresses from healthy liver to chronic hepatitis, cirrhosis, and HCC. Similar alterations of metabolic genes were detected in NASH-HCC mice, which were consistent with the results of metabolomics. As the degree of cancer differentiation decreased, glycolysis and PPP were accelerated; however, FA synthesis and uptake were diminished. Conclusions: The metabolic alterations including glycolysis, PPP, TCA cycle, and ß-oxidation became more prominent as liver disease progresses from normal, chronic hepatitis, cirrhosis, well-, moderately, and poorly differentiated HCC. FA synthesis and uptake were highest in well-differentiated HCC, which could explain the lipid accumulation.

Effects of a surface prereacted glass-ionomer filler coating material on biofilm formation and inhibition of dentin demineralization.

OBJECTIVES: This study investigated the ability of a surface prereacted glass-ionomer (S-PRG) coating material to inhibit the biofilm formation and demineralization of dentin. METHODS AND MATERIALS: Dentin specimens were randomly divided into three groups: (1) no coating (control), (2) S-PRG filler-containing coat, and (3) a nonS-PRG filler-containing coat. Streptococcus mutans biofilms were grown on the dentin surfaces in a microcosm for 20 h. Then, the quantity of bacteria and water-insoluble glucan in the retained biofilm on the dentin surface were measured. Regarding demineralization inhibition test, specimens were demineralized for 5 days then sectioned into halves and observed under confocal laser scanning microscope (CLSM). One-way ANOVA and Tukey's HSD were used for statistical analysis. RESULTS: The estimated mean surface roughness for specimens in the S-PRG group was statistically significantly higher than the estimates for both the nonS-PRG and the control group specimens. The quantity of bacteria and water-insoluble glucan/mm2 revealed that the S-PRG group prevented biofilm formation and bacterial adhesion to the dentin surface compared with the control and nonS-PRG groups. The S-PRG group recorded the highest acid-resistance ability with no surface loss. CONCLUSION: Application of S-PRG barrier coat on dentin surfaces can inhibit biofilm formation as well as protecting the dentin surface against demineralization. CLINICAL SIGNIFICANCE: Coating material containing S-PRG fillers might be used for caries prevention, through inhibiting biofilm formation, enhancing mineralization, and reducing acidic attack by cariogenic bacteria.

Improving MiniHip femoral prosthesis positioning using a cross-laser projection system in total hip arthroplasty by an anterolateral supine approach.

BACKGROUND: The authors developed a cross-laser projection system (CLP) to place a femoral neck-sparing short stem using the minimally invasive anterolateral supine approach in total hip arthroplasty. This study aimed to verify the utility of CLP. METHODS: Thirty joints were assessed with the MiniHip (Corin). The authors compared femoral component implantation with a patient-specific femoral osteotomy guide (PSG) for the femoral neck-cut (PSG group), with the CLP attached to the rasp handle to irradiate the cross-laser to the target of PSG (CLP group), and without PSG or CLP (control group). RESULTS: In the CLP group, the positional deviation of anteversion, anterior/posterior tilt and varus/valgus placement of the stem postoperatively were 1.8° ± 0.2°, 2.0° ± 2.0° and 2.0° ± 0.1°, respectively. The positional deviation of anteversion (p < 0.001) and anterior/posterior tilt (p = 0.036) were significantly smaller than those in the other groups. CONCLUSIONS: CLP improves the accuracy of MiniHip femoral prosthesis placement.

Clinical results of a short stem with flat tapered wedge design in primary total hip arthroplasty for hip dysplasia in Asians.

BACKGROUND: Cementless femoral reconstruction is challenging in hip dysplasia due to deformity of the proximal femur causing insufficient stem fixation and/or inadequate neck anteversion. Strategies to address these problems include the use of a modular stem or a distal fixation stem, but both stems have some characteristic disadvantages. METHODS: We studied the postoperative clinical outcomes in primary total hip arthroplasty in 257 hips using the flat tapered wedge short femoral stem for hip dysplasia in an Asian population (postoperative follow-up period: 2 years to 6 years and 11 months; mean 4 years and 5 months). We took advantage of the characteristic of high flexibility in stem placement because of its low volume, positioning it while performing some varus/valgus and rotational alignment adjustments. RESULTS: Favorable clinical functional outcomes were obtained, including the radiographic outcome of biological fixation achieved in all stems. Regarding complications, there was no case of split fracture of the femoral calcar region during stem insertion, and the rate of postoperative dislocation was also low at 0.4% (1 case). In the pre- and postoperative computed tomography measurements, the variability in stem anteversion postoperatively was significantly reduced compared to preoperative anatomical anteversion. CONCLUSION: This flat-shaped short low-volume stem likely has high flexibility in positioning in cases of hip dysplasia and can be easily positioned to avoid fractures while still achieving secure fixation.

Preventing postoperative prosthetic joint dislocation by repairing obturator externus in total hip arthroplasty performed via the posterior approach.

BACKGROUND: In total hip arthroplasty performed via the posterior approach, repairing the posterior soft tissues is a conventional method for preventing postoperative prosthetic joint dislocation. The aim of this study was to verify whether obturator externus repair played the main role and what was the mechanism of the repair preventing the dislocation. METHODS: Included were 188 patients who underwent primary cementless total hip arthroplasty via the posterior approach. The patients were divided into a repair group (n = 94) and a non-repair group (n = 94). Patients of repair group received additional obturator externus repair while patients of non-repair group did not. The range of motion of hip joint was assessed before and after operation. Data were compared between the two groups. A p value < 0.05 was considered statistically significant. RESULTS: Before operation and under anesthesia, with regard to internal rotation of hip joint, the mean values of repair and non-repair groups were 24° ± 16/28° ± 15 (p = 0.2933). The mean values of the groups were 13° ± 8/15° ± 9 immediately after repair (p = 0.5672). Range of internal rotation 1 year after operation were 15° ± 8/19° ± 9 (p = 0.0139). Specifically, the values in repair group were lower than those in non-repair group. During a 5-year period of postoperative follow-up, hip joint dislocation occurred in one patient of non-repair group. No dislocation was observed in repair group. CONCLUSION: When THA is performed via the posterior approach, repairing the obturator externus may decrease the risk of postoperative prosthetic joint dislocation by reinforcing the posterior soft tissues of the hip joint. LEVEL OF EVIDENCE: Therapeutic study, Level IVa.

Treatment of periprosthetic hip infection with retention of a well-fixed stem: six to 13-year outcomes.

BACKGROUND: Treatment of periprosthetic joint infection (PJI) is challenging, generally requiring complete implant removal. However, recently reported treatments involve partial retention of implants because of the severe local and systemic burden on the patients and difficulties in functional preservation. Long-term results should be evaluated because of the risk of residual biofilm on the retained implant and late infection recurrence. We evaluated 6 to 13-year clinical outcomes of two-stage treatment of chronic PJI retaining well-fixed cementless stems. METHODS: Among 36 surgeries for deep infection following hip arthroplasty performed from 2004 to 2011, six hips had a well-fixed and well-functioning cementless stem. These six hips were all chronic PJI and were treated without stem removal. The first-stage surgery involved acetabular cup removal and reconstruction by filling the acetabular defect with antibiotic-loaded acrylic cement, creating a socket-like hemispherical dent, and reducing the retained femoral head to this dent. After confirming infection eradication the second-stage acetabular reconstruction was performed. One patient died of an unrelated noninfective cause 1 year after the operation. Clinical outcomes of the remaining five patients were followed for 6 to 13 years. RESULTS: Between the two surgeries (range; 2-5 months), patients underwent active range-of-motion and ambulation exercises. No dislocation was found during the interval. No recurrence of infection was found and good functional outcomes and radiographic findings were observed during the average follow-up of 109 months in all five patients. CONCLUSIONS: Two-stage treatment with retention of a well-fixed stem may minimize local and systemic burden of the patient and enhance functional preservation while obtaining long-term infection control. Although further study could establish the effectiveness and indications for this treatment option, currently used indications should be carefully evaluated considering factors including local and systemic conditions of the patient, implant fixation status, and type of bacteria.

Regorafenib could cause sinusoidal obstruction syndrome.

A 74-year-old man with advanced colon cancer was admitted to our hospital with jaundice and ascites. Four weeks before admission, he had started treatment with regorafenib because other chemotherapies had failed. Blood tests showed a characteristic increase in his serum lactate dehydrogenase level, which indicated intrahepatic hypoxia. The liver was not cirrhotic, but Doppler ultrasonography (US) showed that the portal flow was markedly decreased. These findings suggested that his liver failure could be caused by sinusoidal obstruction syndrome (SOS). We therefore started treatment with anticoagulants that included antithrombin III and recombinant thrombomodulin. His portal flow gradually increased, and his hepatic function improved in parallel with the increased flow. Although regorafenib could cause fatal liver failure, the mechanism remains unclear. SOS might be a route by which regorafenib induces liver failure. Additionally, lactate dehydrogenase could be a marker for identifying the adverse effects at an early stage of regorafenib-induced liver failure.