Is the increase in the number of total hip arthroplasties in Japan due to an aging society?

BACKGROUND: The number of total hip arthroplasty (THA) is increasing globally, including Japan. The Japanese Orthopaedic Association has been conducting a registry of joint replacement surgery, but there may be a gap between the reported numbers of THA in the registry and the actual number. This study aimed to investigate the exact number of THA and assess the trends in Japan using the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB). METHODS: We downloaded data from 2014 to 2019 from the NDB Open Data. Data on primary THA were extracted, and we calculated the annual number and number for each 10-year age group and sex. We also compared the number and trends between elderly and non-elderly groups. RESULTS: During the study period, number of THAs increased by approximately 20,000, showing a continuous upward trend. The highest number of THAs were performed on patients in their 60s, except for the years 2014 and 2019. Comparison of the numbers in 2014 and 2019 by age group showed an increase in the number in patients in their 90s (by 2.05 times). There were significantly a greater number of elderly patients (P < 0.001). The number of THAs performed was higher in women than in men (P < 0.001). CONCLUSION: The number of THAs in Japan increased substantially from 2014 to 2019, despite a decrease in population. Significantly higher number of THAs were performed on elderly patients in Japan, which might be due to an aging society. The NDB data is highly valuable for epidemiological research in Japan, as it might enable the early detection of issues occurring during THA, facilitating their prompt integration into daily clinical practice.

The necessity of suction drainage when intra-articular injection of tranexamic acid is used during primary total knee arthroplasty: a retrospective study.

BACKGROUND: Suction drainages are commonly used after total knee arthroplasty (TKA) procedures; however, their use is somewhat controversial. Recently, some reports have claimed that the administration of tranexamic acid (TXA) may prevent postoperative bleeding following TKAs. Although numerous studies have reported regarding different dosages, timings of administration, or drain clamping times for intravenous and intra-articular TXA injections (IA-TXAs), few have examined whether suction drainage is necessary when TXA is administered. In this study, we compared using suction drainage without TXA administration and IA-TXA without suction drainage and aimed to examine the need for suction drainage during IA-TXA. METHODS: This retrospective study was conducted on 217 patients who had received TKA for osteoarthritis; 104 were placed on suction drainage after TKA without TXA (Group A), whereas the remaining 113 received IA-TXA immediately after surgery without suction drainage (Group B). Our clinical evaluation included assessments of the need for transfusion, presence of postoperative complications, incidence of deep vein thrombosis (DVT), and changes in hemoglobin (Hb), hematocrit (Hct), and D-dimer levels. RESULTS: No significant differences were observed in terms of postoperative complications and preoperative Hb, Hct, or D-dimer levels between the two groups. Although the prevalence of DVT was significantly higher in Group B (p < 0.05), all cases were asymptomatic. Hb and Hct levels were significantly lower in Group A than in Group B at 1, 3, 7, and 14 days postoperatively (p < 0.05), although none of the cases required blood transfusions. D-dimer levels were significantly higher in Group A than in Group B at 1 and 3 days postoperatively (p < 0.05). CONCLUSION: Suction drainage might not be necessary when IA-TXA is administered after TKA procedures.

Fibrocyte Phenotype of ENTPD1+CD55+ Cells and Its Association with Pain in Osteoarthritic Synovium.

Osteoarthritis (OA) is a prevalent degenerative joint disorder characterized by cartilage erosion, structural changes, and inflammation. Synovial fibroblasts play a crucial role in OA pathophysiology, with abnormal fibroblastic cells contributing significantly to joint pathology. Fibrocytes, expressing markers of both hematopoietic and stromal cells, are implicated in inflammation and fibrosis, yet their marker and role in OA remain unclear. ENTPD1, an ectonucleotidase involved in purinergic signaling and expressed in specific fibroblasts in fibrotic conditions, led us to speculate that ENTPD1 plays a role in OA pathology by being expressed in fibrocytes. This study aimed to investigate the phenotype of ENTPD1+CD55+ and ENTPD1-CD55+ synovial fibroblasts in OA patients. Proteomic analysis revealed a distinct molecular profile in ENTPD1+CD55+ cells, including the upregulation of fibrocyte markers and extracellular matrix-related proteins. Pathway analysis suggested shared mechanisms between OA and rheumatoid arthritis. Correlation analysis revealed an association between ENTPD1+CD55+ fibrocytes and resting pain in OA. These findings highlight the potential involvement of ENTPD1 in OA pain and suggest avenues for targeted therapeutic strategies. Further research is needed to elucidate the underlying molecular mechanisms and validate potential therapeutic targets.

Trends in hip preservation surgery in Japan from 2014 to 2019 with a focus on hip arthroscopic surgery.

Secondary hip osteoarthritis due to hip dysplasia is common among Japanese populations. This study aimed to investigate the number of hip preservation surgeries performed in Japan and assess trends, by age and sex, from 2014 to 2019, focusing on hip arthroscopic surgery, based on the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB). We downloaded the files 'Number of calculations by division, sex, and age group' under 'operation (code K)' from 2014 to 2019 from the NDB Open Data Japan database. Data on hip preservation surgeries were extracted, including the number for each surgical procedure and its incidence per year, calculated as the number of surgeries performed for each 10-year age group and by sex, regarding hip arthroscopic surgery. Overall, 14 891 hip preservation surgeries were performed in Japan over the study period, with pelvic osteotomy being the most common procedure. Although the incidence of hip preservation surgeries decreased from 2014 to 2019, there was a specific 1.54-fold higher incidence in hip arthroscopic procedures in 2019 compared to 2014. Hip arthroscopic labral repair was performed more frequently than synovectomy. The highest incidence of hip arthroscopic surgery was in the 40- to 49-years age group, with no difference in incidence between sexes (P = 0.951). In Japan, pelvic osteotomy was performed more often as a hip preservation surgery than hip arthroscopic surgery. Although hip arthroscopic surgery was developed in Japan, its use has not increased from 2017 to 2019.

A novel primary stability test method for artificial acetabular shells considering vertical load during level walking and shell position.

Uncemented acetabular shell primary stability is essential for optimal clinical outcomes. Push-out testing, rotation testing, and lever-out testing are major evaluation methods of primary stability between the shell and bone. However, these test methods do not consider shell loads during daily activity and shell installation angle. This study proposes a novel evaluation method of acetabular shell primary stability considering load during level walking and acetabular installation angles such as inclination and anteversion. To achieve this, a novel primary stability test apparatus was designed with a shell position of 40° acetabular inclination and 20° anteversion. The vertical load, corresponding to walking load, was set to 3 kN according to ISO 14242-1, which is the wear test standard for artificial hip joints. The vertical load was applied by an air cylinder controlled by a pressure-type electro-pneumatic proportional valve, with the vertical load value monitored by a load cell. Torque was measured when angular displacement was applied in the direction of extension during the application of vertical load. For comparison, we also measured torque using the traditional lever-out test. The novel primary stability test yielded significantly higher primary stabilities; 5.4 times greater than the lever-out test results. The novel primary stability test failure mode was more similar to the clinical failure than the traditional lever-out test. It is suggested that this novel primary stability test method, applying physiological walking loads and extension motions to the acetabular shell, better reflects in vivo primary stability than the traditional lever-out test.

The Impact of Sarcopenia Risk on Postoperative Walking Independence in Older Adults Undergoing Total Joint Arthroplasty.

BACKGROUND AND PURPOSE: Sarcopenia is known to be associated with poor outcomes after arthroplasty; however, no study has reported the relationship between sarcopenia and postoperative walking independence. This study aimed to determine the impact of sarcopenia risk screening using the SARC-CalF questionnaire and calf circumference on the time to walk independently after total hip or knee arthroplasty in older patients. METHODS: We included 599 nonobese patients aged 65 years and older who underwent unilateral and primary total hip or knee arthroplasty. Preoperative sarcopenia risk was assessed using the SARC-CalF or calf circumference. The outcome of this study was the time to independent walking after surgery; it was calculated as the number of days from the date of surgery to the date when the patient was able to walk independently. The association between preoperative sarcopenia risk and time to independent walking after surgery was analyzed using Kaplan-Meier curves and Cox proportional hazards models. RESULTS: Among the 599 patients undergoing total joint arthroplasty, 175 (29.2%) were determined to be at risk of sarcopenia using SARC-CalF and 193 (32.2%) using calf circumference. The Kaplan-Meier curve showed that sarcopenia risk assessed by SARC-CalF or calf circumference was associated with a prolonged time to independent walking in patients undergoing hip arthroplasty (log-rank test, P < .001 and P < .001, respectively). In patients undergoing hip arthroplasty, the Cox proportional hazards model showed that SARC-CalF score of 11 points and greater or a calf circumference less than the cutoff was a risk factor for delayed time to independent walking (hazard ratios: 0.55 and 0.57, P < .001 and P = .001, respectively). There was no association between preoperative sarcopenia risk and postoperative time to independent walking in patients who underwent knee arthroplasty. CONCLUSIONS: Sarcopenia screening tools, such as SARC-CalF or calf circumference, should be useful for planning postoperative rehabilitation in older adults scheduled for hip arthroplasty. However, the accuracy of SARC-CalF or calf circumference measurement in patients scheduled for knee arthroplasty may be low.

Association of affected and non-affected side ability with postoperative outcomes in patients undergoing total hip arthroplasty.

BACKGROUND: Although several reports have examined the association between preoperative function and postoperative outcomes in patients undergoing total hip arthroplasty (THA), it is unclear whether the ability of the affected or non-affected side particularly impacts on outcomes. We aimed to investigate the association between affected and non-affected side ability and walking independence. METHODS: We prospectively enrolled 721 consecutive patients who underwent THA. Preoperatively, quadriceps isometric strength (QIS) and one-leg standing time (OLST) were measured. The endpoints were walking independence within 3, 5, 7, 10, and 14 days postoperatively. The associations between preoperative abilities and outcomes were examined using multivariate Cox hazard model, and the area under the curves (AUCs) for outcomes were compared. RESULTS: We analysed 540 patients after excluding patients who met the exclusion criteria. Both affected and non-affected QIS predicted walking independence within 3 (p = 0.006 and 0.001, respectively), 5, 7, 10, and 14 (both p < 0.001) days postoperatively. For OLST, only the affected side did not predict walking independence within 3 days postoperatively (p = 0.154 and 0.012, respectively), and both sides did at days 5 (p = 0.019 and <0.001, respectively), 7, 10, and 14 (both p < 0.001). The AUCs of the non-affected side ability for walking independence were significantly greater than those of the affected side on postoperative days 3 (0.66 vs. 0.73; p = 0.021) and 5 (0.67 vs. 0.71; p = 0.040), with no significant difference after day 7. CONCLUSIONS: Both sides abilities were associated with walking independence after THA, but non-affected side was found to be particularly crucial for early walking independence.

CD39+CD55- Fb Subset Exhibits Myofibroblast-Like Phenotype and Is Associated with Pain in Osteoarthritis of the Knee.

Recent studies utilizing single-cell analysis have unveiled the presence of various fibroblast (Fb) subsets within the synovium under inflammatory conditions in osteoarthritis (OA), distinguishing them from those in rheumatoid arthritis (RA). Moreover, it has been reported that pain in knee OA patients is linked to specific fibroblast subsets. Single-cell expression profiling methods offer an incredibly detailed view of the molecular states of individual cells. However, one limitation of these methods is that they require the destruction of cells during the analysis process, rendering it impossible to directly assess cell function. In our study, we employ flow cytometric analysis, utilizing cell surface markers CD39 and CD55, in an attempt to isolate fibroblast subsets and investigate their relationship with OA pathology. Synovial tissues were obtained from 25 knee OA (KOA) patients. Of these, six samples were analyzed by RNA-seq (n = 3) and LC/MS analysis (n = 3). All 25 samples were analyzed to estimate the proportion of Fb (CD45-CD31-CD90+) subset by flow cytometry. The proportion of Fb subsets (CD39+CD55- and CD39-CD55+) and their association with osteoarthritis pathology were evaluated. CD39+CD55- Fb highly expressed myogenic markers such as CNN1, IGFBP7, MYH11, and TPM1 compared to CD39-CD55+ Fb. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of upregulated differentially expressed genes (DEGs) in CD39+CD55- Fb identified the Apelin pathway and cGMP-PKC-signaling pathway as possibly contributing to pain. LC/MS analysis indicated that proteins encoded by myogenic marker genes, including CNN1, IGFBP7, and MYH11, were also significantly higher than in CD39-CD55+ Fb. CD39-CD55+ Fb highly expressed PRG4 genes and proteins. Upregulated DEGs were enriched for pathways associated with proinflammatory states ('RA', 'TNF signaling pathway', 'IL-17 signaling pathway'). The proportion of CD39+CD55- Fb in synovium significantly correlated with both resting and active pain levels in knee OA (KOA) patients (resting pain, ρ = 0.513, p = 0.009; active pain, ρ = 0.483, p = 0.015). There was no correlation between joint space width (JSW) and the proportion of CD39+CD55- Fb. In contrast, there was no correlation between the proportion of CD39-CD55+ Fb and resting pain, active pain, or JSW. In conclusion, CD39+CD55- cells exhibit a myofibroblast phenotype, and its proportion is associated with KOA pain. Our study sheds light on the potential significance of CD39+CD55- synovial fibroblasts in osteoarthritis, their myofibroblast-like phenotype, and their association with joint pain. These findings provide a foundation for further research into the mechanisms underlying fibrosis, the impact of altered gene expression on osteoarthritic joints, and potential therapeutic strategies.

Increase in TPSB2 and TPSD1 Expression in Synovium of Hip Osteoarthritis Patients Who Are Overweight.

While research suggests that increasing body mass index (BMI) is a risk factor for hip osteoarthritis (HOA), the mechanisms of this effect are not fully understood. Tryptases are among the main proteases found in mast cells (MCs) and contribute to OA pathology. TPSB2, which encodes ß-tryptase, is increased in the synovium of overweight and obese knee OA patients. However, it remains unclear whether tryptase in the synovium of HOA is increased with increasing BMI. Here, we investigated tryptase genes (TPSB2 and TPSD1) in the synovium of overweight HOA patients. Forty-six patients radiographically diagnosed with HOA were allocated to two groups based on BMI, namely normal (<25 kg/m2) and overweight (25-29.99 kg/m2). TPSB2 and TPSD1 expression in the synovium of the two groups was compared using real-time polymerase chain reaction. To compare TPSB2 and TPSD1 expression in MCs between the groups, we isolated the MC-rich fraction (MC-RF) and MC-poor fraction (MC-PF), extracted using magnetic isolation. TPSB2 and TPSD1 expression was increased in the overweight group compared with the normal group. Expression of both genes in the MC-RF was significantly higher than that in MC-PF in both groups. However, TPSB2 and TPSD1 expression levels in the MC-RF did not differ between the groups. Tryptase genes were highly expressed in the synovium of overweight HOA patients. Further investigation to reveal the role of tryptase in the relationship between increasing BMI and HOA pathology is required.

In situ-formed hyaluronan gel/BMP-2/hydroxyapatite composite promotes bone union in refractory fracture model mice.

BACKGROUND: A combination of synthetic porous materials and BMP-2 has been used to promote fracture healing. For bone healing to be successful, it is important to use growth factor delivery systems that enable continuous release of BMP-2 at the fracture site. We previously reported that in situ-formed gels (IFGs) consisting of hyaluronan (HyA)-tyramine (TA), horseradish peroxidase and hydrogen peroxide enhance the bone formation ability of hydroxyapatite (Hap)/BMP-2 composites in a posterior lumbar fusion model. OBJECTIVE: We examined the effectiveness of IFGs-HyA/Hap/BMP-2 composites for facilitating osteogenesis in refractory fracture model mice. METHODS: After establishing the refractory fracture model, animals were either treated at the site of fracture with Hap harboring BMP-2 (Hap/BMP-2) or IFGs-HyA with Hap harboring BMP-2 (IFGs-HyA/Hap/BMP-2) (n = 10 each). Animals that underwent the fracture surgery but did not receive any treatment were considered the control group (n = 10). We determined the extent of bone formation at the fracture site according to findings on micro-computed tomography and histological studies four weeks following treatment. RESULTS: Animals treated with IFGs-HyA/Hap/BMP-2 demonstrated significantly greater bone volume, bone mineral content and bone union than those treated with vehicle or IFG-HyA/Hap alone. CONCLUSIONS: IFGs-HyA/Hap/BMP-2 could be an effective treatment option for refractory fractures.

Mechanisms of Peripheral and Central Sensitization in Osteoarthritis Pain.

Pain, the primary symptom of osteoarthritis (OA), reduces both the quality and quantity of life for patients. The pathophysiology of OA pain is complex and often difficult to explain solely by radiological structural changes. One reason for this discrepancy is pain sensitization (peripheral sensitization [PS] and central sensitization [CS]) in OA. Thus, an understanding of pain sensitization is important when considering treatment strategies and development for OA pain. In recent years, pro-inflammatory cytokines, nerve growth factors (NGFs), and serotonin have been identified as causative agents that induce peripheral and central sensitization and are becoming therapeutic targets for OA pain. However, the characteristics of the clinical manifestations of pain sensitization elicited by these molecules remain unclear, and it is not well understood who among OA patients should receive the therapeutic intervention. Thus, this review summarizes evidence on the pathophysiology of peripheral and central sensitization in OA pain and the clinical features and treatment options for this condition. While the majority of the literature supports the existence of pain sensitization in chronic OA pain, clinical identification and treatment of pain sensitization in OA are still in their infancy, and future studies with good methodological quality are needed.

A Modified Sliding-Lengthening Approach to Tendon Lengthening with a Locking Mechanism Suture: A Technical Note.

There are various techniques used for tendon lengthening, of which Z-lengthening and sliding-lengthening are the most frequently performed. In patients with cerebral palsy, tendon lengthening may often be necessary at multiple sites. However, they can cause various complications, such as inaccurate extension, overextension, and a lack of tendon continuity. We modified the sliding-lengthening technique with a locking mechanism to address these issues. This technical note aims to describe the surgical technique and pitfalls associated with the modified sliding-lengthening approach and suture locking mechanism. The tendon was exposed and stabilized using sterilized spitz tubes and was then threaded so that each loop length was equivalent to the amount of tendon extension. Symmetrical hemisection of both ends of the tendon was performed, and the tendon was carefully extended to create a tense loop. The modified sliding-lengthening technique with the locking suture mechanism may be an advantageous method that accurately addresses extension volume, prevents hyperextension, and maintains tendon continuity, even when smaller incisions are used.

Increased Synovial CD14 mRNA Expression and Proportion of CD14high Subsets in Early-Stage Hip Osteoarthritis: Propensity Matched Score Analysis.

The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary.

Sports activity participation and subjective health status of patients after total hip arthroplasty via the anterolateral-supine approach: a case series study.

BACKGROUND: No reports have been published about participation in sports activity and subjective health status after total hip arthroplasty via the anterolateral approach in the supine position (ALS-THA) in Japanese patients. This study assessed sports activity participation and subjective health status, as well as factors potential associated with these variables, in patients who underwent ALS-THA. METHODS: Of 698 patients who underwent total hip arthroplasty at our institution between 2013 and 2018, questionnaires were sent to 355 patients under 80 years old who had undergone ALS-THA and 242 responded. Patients were asked about their subjective health status, participation in sports activity, the EuroQol 5-dimensions 5-level (EQ-5D-5L), the University of California Los Angeles (UCLA) activity scale score and the Forgotten Joint Score (FJS). Patient characteristics and hospitalization information were also collected. Patients' subjective health status was categorized as "healthy" or "unhealthy". Univariate and multivariate logistic regression analyses were performed to determine factors associated with participation in sports activity after ALS-THA and a "healthy" status. RESULTS: The pre- and postoperative sports activity participation rates were 54.0% and 57.8%, respectively. Most patients (76.8%, n = 182) were considered "healthy". Age (P = .019) and UCLA activity score (P < .001) were significantly associated with sports activity after ALS-THA. FJS (P = .002) and EQ-5D-5L (P = .004) were significantly associated with a "healthy" status. CONCLUSION: Patients participating in sports activity after ALS-THA are older and have higher UCLA activity scores and patients considered "healthy" have higher FJS and EQ-5D-5L scores.

Is bone marrow oedema in patients with labral tear an indicator of hip pain?

BACKGROUND: Hip labral tear (LT) causes various degrees of hip pain, for which there are few objective measures. Bone marrow oedema (BME), characterized by a diffuse, widely spreading change in the bone marrow, is observed in some patients with LT. However, its pathological role has not been fully understood. The purpose of this study was to investigate the prevalence of BME on hip magnetic resonance imaging (MRI) in patients with LT and to determine whether BME was an objective indicator of hip pain. METHODS: In total, 84 patients with LT who underwent MRI scanning under the same conditions were included. We determined the presence or absence of BME and its size on MRI and evaluated the relationships between BME and sex, age, and pain and total scores on the modified Harris hip score (MHHS). In addition, we collected data on surgical treatments such as hip arthroscopy within a one-year follow-up period and examined whether the presence of BME affected the course of therapy. RESULTS: BME was found in 34.5% of patients. MHHS pain and total scores were significantly lower in patients with BME (MHHS pain score: non-BME vs. BME ≤ 1 cm: p = 0.022, non-BME vs. BME > 1 cm: p < 0.001; MHHS total score: non-BME vs. BME ≤ 1 cm: p = 0.131, non-BME vs. BME > 1 cm: p = 0.027). The presence of BME did not differ between patients who did and did not undergo surgery during follow-up (p = 0.563). CONCLUSION: BME on MRI in patients with LT might be an indicator of hip pain and hip joint dysfunction.

Differences in outcomes after total hip arthroplasty for osteoarthritis between patients with and without central sensitivity syndromes other than fibromyalgia.

We investigated the differences in outcomes after total hip arthroplasty (THA) for hip osteoarthritis (HOA) between patients with and without central sensitivity syndromes (CSSs) other than fibromyalgia (FM). After excluding two patients with FM, we compared the clinical data of 41 patients with CSSs and 132 patients without CSSs. Clinical data included scores on the central sensitization inventory, visual analog scale for pain (VAS pain), and Japanese Orthopedic Association Hip Disease Evaluation Questionnaire (JHEQ). VAS pain was significantly higher at 3 and 6 months after THA in patients with CSSs than in those without CSSs (3 and 6 months, P < 0.001). Satisfaction, pain, and mental JHEQ scores were lower in patients with CSSs than in those without CSSs (satisfaction, P < 0.001; pain, P = 0.011; mental, P = 0.032). Multiple regression analyses indicated that one and ≥ 2 CSS diagnoses significantly impacted the satisfaction score (one CSS, ß = - 0.181, P = 0.019; ≥ 2 CSSs, ß = - 0.175, P = 0.023). Two or more CSSs were the only factor influencing the pain score (ß = - 0.175, P = 0.027). Pain in patients with CSSs reflects central sensitization, which may adversely affect post-operative outcomes. Surgeons should pay attention to patients with a history of CSSs diagnoses who undergo THA for HOA.

TNF-α Suppresses Apelin Receptor Expression in Mouse Quadriceps Femoris-Derived Cells.

Expression of the apelin receptor, APJ, in skeletal muscle (SM) is known to decrease with age, but the underlying mechanism remains unclear. Increased tumor necrosis factor (TNF)-α levels are observed in SM with age and are associated with muscle atrophy. To investigate the possible interconnection between TNF-α elevation and APJ reduction with aging, we investigated the effect of TNF-α on APJ expression in cells derived from the quadriceps femoris of C57BL/6J mice. Expression of Tnfa and Apj in the quadriceps femoris was compared between 4- (young) and 24-month-old (old) C57BL/6J mice (n = 10 each) using qPCR. Additionally, APJ-positive cells and TNF-α protein were analyzed by flow cytometry and Western blotting, respectively. Further, quadricep-derived cells were exposed to 0 (control) or 25 ng/mL TNF-α, and the effect on Apj expression was examined by qRT-PCR. Apj expression and the ratio of APJ-positive cells among quadricep cells were significantly lower in old compared to young mice. In contrast, levels of Tnfa mRNA and TNF-α protein were significantly elevated in old compared to young mice. Exposing young and old derived quadricep cells to TNF-α for 8 and 24 h caused Apj levels to significantly decrease. TNF-α suppresses APJ expression in muscle cells in vitro. The increase in TNF-α observed in SM with age may induce a decrease in APJ expression.

Using allogenous structural bone graft for uncontained tibial bone defects ≥ 10 mm in depth in primary total knee arthroplasty.

BACKGROUND: In primary total knee arthroplasty (TKA), tibial bone defects ≥ 10 mm in depth often become uncontained defects, a condition most surgeons find challenging to treat. Although the allogenous bone graft is a useful method, complications such as infection and nonunion are likely to occur. There are several reports on the use of allogenous bone graft in revision TKA; however, few studies have investigated its use in primary TKA. We performed primary TKA using the allogenous bone graft as a structural bone graft to treat uncontained defects ≥ 10 mm in depth. This study aimed to assess the clinical and radiographical results after primary TKA with allogenous structural bone graft (ASBG). METHODS: Seventeen patients (mean age, 69.2 years) with a follow-up period of at least 7 years, were retrospectively reviewed. All cases had been treated for medial bone defects using the ipsilateral medial tibial allogenous bone. Clinical evaluation included the assessment of the knee and function scores and knee angle, and the hip-knee-ankle (HKA) angle, bone union, and radiolucent line (RL) were assessed radiologically. RESULTS: The mean depth of the medial tibial defects after tibia cutting was 16.8 mm. Nonunion occurred in one case, and RL occurred in another. We observed a significant difference when the preoperative knee score and HKA angle of patients was compared with that at 1 year postoperatively and the final evaluation. No major complications were observed. CONCLUSION: The ASBG technique produced favorable surgical outcomes and may be an acceptable procedure for managing uncontained tibial bone defects ≥ 10 mm in depth in primary TKA.

Femoral varus derotational osteotomy without pelvic osteotomy in nonambulatory children with cerebral palsy: Minimum 5 years follow-up.

ABSTRACT: Whether femoral varus derotational osteotomy (VDRO) alone or a combination of femoral and pelvic osteotomies should be performed for hip dislocation in nonambulatory children with cerebral palsy (CP) remains controversial. Few studies have reported radiographical results after the surgical treatment in nonambulatory children with CP. This study aimed to assess the results and determine predictors indicating progressive hip subluxation and redislocation after VDRO without pelvic osteotomy. We retrospectively analyzed 22 hips in 15 nonambulatory children with CP. All patients underwent VDRO without pelvic osteotomy and were followed up for at least 5 years. The mean follow-up period was 7.3 ±â€Š1.9 years. In radiological assessments, we investigated migration percentage (MP), center-edge angle, neck-shaft angle, teardrop distance, break in Shenton's line (SL), sharp's angle, acetabular ridge angle (ARA), and the change ratio of MP (Change MP). We classified patients with an MP of <40% at final follow-up in the Good group and those with an MP of ≥40% in the Poor group. The Good group included 10 children (14 hips), and the Poor group included 8 children (8 hips). No preoperative differences were found in the means of all the radiographical parameters. However, MP was significantly different between the groups from 1 year postoperatively. ARA showed improvement 5 years after surgery in the Good group. Change MP in the Good group was maintained from immediately after surgery to the final follow-up. Multivariate logistic regression analyses revealed that preoperative break in SL and Change MP immediately after surgery were parameters to predict MP at the final follow-up. In the receiver operating characteristic analysis, the cut-off values were estimated to be 19.2 mm for preoperative SL and 79.0% for Change MP immediately after surgery. Within 7.3 years of follow-up, 63.6% of the patients who underwent VDRO without pelvic osteotomy had good results. Preoperative SL and postoperative Change MP can be considered as predictors of postoperative subluxation and/or dislocation.