Do standardization of the procedure reduce measurement variability of the sonographic anterior drawer test of the ankle?

BACKGROUND: In quantitative ankle stress sonography, different examiners use different techniques, which may cause measurement variability. This study aimed to clarify whether standardizing stress sonography techniques reduces variability in the quantitative measurement of anterior talofibular ligament length change. METHODS: Fourteen examiners with a mean ultrasound experience of 8.7 years participated in this study. Each examiner performed stress ultrasonography of the ankle using their preferred method on one patient with an intact anterior talofibular ligament (Patient 1) and on two patients with chronic ankle instability (Patient 2 and 3). Changes in the ligament length between the resting and stressed positions were determined. A consensus meeting was then conducted to standardize the sonographic technique, which was used by the examiners during a repeat stress sonography on the same patients. The variance and measured values were compared between the preferred and standardized techniques using F-tests and paired t-tests, respectively. RESULTS: At a consensus meeting, a sonographic technique in which the examiner pushed the lower leg posteriorly against the fixed foot was adopted as the standardized technique. In Patient 1, the change in the anterior talofibular ligament length was 0.4 (range, -2.3-1.3) mm and 0.6 (-0.6-1.7) mm using the preferred and standardized techniques, respectively, with no significant difference in the variance (P = 0.51) or the measured value (P = 0.52). The length changes in Patient 2 were 2.0 (0.3-4.4) mm and 1.7 (-0.9-3.8) mm using the preferred and standardized techniques, respectively. In Patient 3, the length changes were 1.4 (-2.7-7.1) mm and 0.7 (-2.0-2.3) mm. There were no significant differences between the techniques in either patient group. CONCLUSION: Variability in the quantitative measurement of ankle stress sonography was not reduced despite the standardization of the technique among examiners. Hence, comparing the measured values between different examiners should be avoided.

Association of Preoperative Depression Score With Outcomes of Transfibular Total Ankle Arthroplasty.

Favorable short-term results of transfibular total ankle arthroplasty have been reported in several studies; however, the factors affecting these results have not been elucidated. This study aimed to determine whether preoperative depression affects the outcome of transfibular total ankle arthroplasty and whether depression changes with surgery. Scores from the Japanese Society of Surgery of the Foot Ankle/Hindfoot scale (JSSF scale), Self-Administered Foot Evaluation Questionnaire (SAFE-Q), Hospital Anxiety and Depression Scale (HADS), and Timed Up & Go test (TUG) were collected preoperatively, at 6 months, and at 1 year postoperatively from 20 patients. Eighteen patients were diagnosed with osteoarthritis and 2 patients with rheumatoid arthritis. The mean age of the patients was 75 years. Patients were divided into 2 groups: those with preoperative HADS depression scores above the median (higher depression score group) and below the median (lower depression score group), and intergroup comparisons were made. No significant differences were observed in the JSSF and TUG scores between the groups, both preoperatively and postoperatively. Meanwhile, the SAFE-Q pain subscale score was significantly lower in the higher depression score group than in the lower depression score group (median, 59 vs 90) 1 year postoperatively. There were no differences in the other SAFE-Q subscale scores between the groups. The results suggested that depressive tendencies did not affect postoperative functional results using objective assessment measures but had a negative impact on pain in subjective assessment measures.

Impact of pain in other body regions on the foot-specific quality of life in patients with hallux valgus.

OBJECTIVES: The purpose of this study was to clarify the prevalence of pain outside the foot, and to determine the associations of pain outside the foot with foot-specific quality of life (QOL) in patients with hallux valgus. METHODS: Patients scheduled to undergo hallux valgus surgery were recruited. Patients answered whether they experienced disabling pain in 13 body regions other than the foot. Foot-specific QOLwas assessed using the Self-Administered Foot Evaluation questionnaire (SAFE-Q). Foot pain was quantified using the visual analogue scale (VAS). Patient characteristics, including age, sex, comorbidity, anxiety, and depression, were also surveyed. The association between pain elsewhere and the SAFE-Q and pain VAS scores were assessed using univariate and multivariate analyses. RESULTS: Of 102 patients, 55 (54%) experienced pain other than the foot. All SAFE-Q subscale scores were lower, and pain VAS was higher in patients with pain elsewhere than in patients without. In the multivariate analysis, an increase in the number of pain regions was independently associated with a decrease in SAFE-Q scores and an increase in pain VAS. CONCLUSION: More than half of the patients with hallux valgus experienced pain elsewhere. The presence of pain elsewhere was associated with poorer foot-specific QOL and severer foot pain.

Evaluations of daily teriparatide using finite-element analysis over 12 months in rheumatoid arthritis patients.

INTRODUCTION: The objective of this study was to quantitatively evaluate the effects of daily teriparatide on rheumatoid arthritis patients using predicted bone strength (PBS) assessed by quantitative computed tomography-based finite-element analysis (QCT/FEA) and using bone mineral density (BMD) assessed by dual-energy X-ray absorptiometry (DXA), and to prospectively investigate clinical determinants associated with PBS and BMD increases. MATERIALS AND METHODS: Participants comprised 39 patients (mean age, 69 years; disease activity score assessing 28 joints with CRP, 3.0; previous vertebral fractures, 82%) enrolled in this study. BMD by DXA and PBS by QCT/FEA of lumbar spine (LS) and proximal femur were measured at baseline, and after 6 and 12 months. In the groups showing increases in these values, variables that may have affected these increases were evaluated using univariate logistic regression analysis. RESULTS: Daily teriparatide treatment significantly increased not only LS BMD, but also LS PBS in RA patients with osteoporosis after both 6 and 12 months of treatment. Increases in N-terminal type I procollagen propeptide (PINP) at 1 and 3 months were significantly associated with increased LS PBS at 12 months according to univariate logistic regression analysis. The threshold value for increased PINP at 1 month for increased PBS at 12 months was 75 µg/L. CONCLUSIONS: Increased LS PBS at 12 months was predicted by increased PINP at 1 month from baseline.

Disease activity affects the recurrent deformities of the lesser toes after resection arthroplasty for rheumatoid forefoot deformity.

OBJECTIVES: The purpose of this study was to clarify the effect of disease activity on recurrent deformities after resection arthroplasty for forefoot deformities in patients with rheumatoid arthritis (RA). METHODS: This study included 83 feet in 58 patients with RA who underwent resection arthroplasty of all metatarsal heads, with a minimum follow-up of 2 years. The patients' demographic characteristics, preoperative radiographic findings, and RA disease activity evaluated using the 28-joint disease activity score based on the erythrocyte sedimentation rate (determined preoperatively and at the final follow-up) were compared between feet with and without postoperative recurrent deformities of the toes. Recurrent deformities were assessed separately for the hallux and lesser toes. RESULTS: Recurrence in the hallux and lesser toes occurred in 23 feet (27.7%) and 13 feet (15.7%), respectively. With respect to recurrent hallux deformity, only the preoperative severity of hallux deformity was associated with recurrence. On the other hand, postoperative deformity of the lesser toes was positively associated with disease activity alone and not with other preoperative factors. CONCLUSION: Postoperative control of RA disease activity was associated with recurrent deformity of the lesser toes but not that of the hallux after resection arthroplasty of all metatarsals for rheumatoid forefoot deformities.

Diagnosis of avulsion fractures of the distal fibula after lateral ankle sprain in children: a diagnostic accuracy study comparing ultrasonography with radiography.

BACKGROUND: The purpose of this study was to determine the diagnostic accuracy of ultrasonography for the diagnosis of avulsion fractures of the distal fibula for lateral ankle sprain in children and compare it to that of radiography. METHODS: Children who sustained lateral ankle sprain were prospectively surveyed. They underwent both ultrasonography and radiography at the first clinic visit to diagnose any concomitant avulsion fractures of the distal fibula. The patients underwent follow-up radiography 4 weeks later to obtain the reference standard diagnosis. The measures of diagnostic accuracy (i.e., sensitivity, specificity, positive predictive value, and negative predictive value) of the initial ultrasonography and radiography were calculated; they were then compared using the McNemar test. Totally, 52 patients (with a median age of 9 years) were analyzed. RESULTS: On the reference standard (follow-up) radiographs, 32 patients (62%) were found to have avulsion fractures of the distal fibula. The sensitivity, specificity, positive predictive value, and negative predictive value for ultrasonography were 94, 85, 91, and 89% respectively; and 81, 100, 100, and 77% respectively for radiography at the first visit. There were no significant differences in sensitivity and specificity between the two diagnostic methods (P = 0.22, 0.25). CONCLUSIONS: Ultrasonography has a high diagnostic accuracy, which is comparable to that of radiography, for the diagnosis of avulsion fracture of the distal fibula. Ultrasonography may be used as an option of imaging modality for lateral ankle sprain in children.

Prior Treatment with Anti-High Mobility Group Box-1 Antibody Boosts Human Neural Stem Cell Transplantation-Mediated Functional Recovery After Spinal Cord Injury.

Together with residual host neurons, transplanted neural stem cell (NSC)-derived neurons play a critical role in reconstructing disrupted neural circuits after spinal cord injury (SCI). Since a large number of tracts are disrupted and the majority of host neurons die around the lesion site as the damage spreads, minimizing this spreading and preserving the lesion site are important for attaining further improvements in reconstruction. High mobility group box-1 (HMGB1) is a damage-associated molecular pattern protein that triggers sterile inflammation after tissue injury. In the ischemic and injured brain, neutralization of HMGB1 with a specific antibody reportedly stabilizes the blood-brain barrier, suppresses inflammatory cytokine expression, and improves functional recovery. Using a SCI model mouse, we here developed a combinatorial treatment for SCI: administering anti-HMGB1 antibody prior to transplantation of NSCs derived from human induced pluripotent stem cells (hiPSC-NSCs) yielded a dramatic improvement in locomotion recovery after SCI. Even anti-HMGB1 antibody treatment alone alleviated blood-spinal cord barrier disruption and edema formation, and increased the number of neurites from spared axons and the survival of host neurons, resulting in functional recovery. However, this recovery was greatly enhanced by the subsequent hiPSC-NSC transplantation, reaching an extent that has never before been reported. We also found that this improved recovery was directly associated with connections established between surviving host neurons and transplant-derived neurons. Taken together, our results highlight combinatorial treatment with anti-HMGB1 antibody and hiPSC-NSC transplantation as a promising novel therapy for SCI. Stem Cells 2018;36:737-750.

Neural stem cell therapy aiming at better functional recovery after spinal cord injury.

Injury to the spinal cord causes transection of axon fibers and neural cell death, resulting in disruption of the neural network and severe functional loss. Reconstruction of the damaged neural circuits was once considered to be hopeless as the adult mammalian central nervous system has very poor ability to regenerate. For this reason, there is currently no effective therapeutic treatment for spinal cord injury (SCI). However, with recent developments in stem cell research and cell culture technology, regenerative therapy using neural stem cell (NSC) transplantation has rapidly been developed, and this therapeutic strategy makes it possible to rebuild the destroyed neural circuits. In this review, we discuss the recent breakthroughs in NSC transplantation therapy for SCI. Developmental Dynamics 247:75-84, 2018. © 2017 Wiley Periodicals, Inc.

Synovial Metallosis After Ceramic Total Ankle Arthroplasty Treated With a Total Talar Prosthesis: A Case Report.

Total ankle arthroplasty is a useful surgical procedure for osteoarthritis of the ankle, but aseptic loosening of components is an issue. We report here a case of aseptic implant loosening with metallosis after total ankle arthroplasty using the TNK ankle (Kyocera, Kyoto, Japan), which occurred despite the components being ceramic. We also report favorable results from our method of treatment using a total talar prosthesis in the revision surgery. During the revision surgery, synovial metallosis was found, probably related to superficial damage to the screw affixing the tibial component to the bone. Because both the tibial and talar components were loose, all the components and the remaining talar bone were removed. A new tibial component and a custom-made alumina-ceramic total talar prosthesis was inserted. Pain relief was achieved and maintained through the latest follow-up visit at 42 months after revision surgery. Dorsiflexion of the ankle improved from 0° to 5° and plantarflexion remained unchanged from its preoperative range of 20°. The American Orthopaedic Foot & Ankle Society ankle-hindfoot score improved from 38 to 80 points. To the best of our knowledge, this is the first reported case of an alumina-ceramic total ankle prosthesis loosening caused by metallosis resulting from screw abrasion. Favorable treatment results were obtained by using a total talar prosthesis in the revision surgery.

Assessing joint destruction in the knees of patients with rheumatoid arthritis by using a semi-automated software for magnetic resonance imaging: therapeutic effect of methotrexate plus etanercept compared with methotrexate monotherapy.

OBJECTIVES: To evaluate the prevention of knee joint destruction and clinical efficacy of methotrexate (MTX) plus etanercept (ETN) compared with MTX monotherapy in patients with rheumatoid arthritis (RA) by using semi-automated software for magnetic resonance imaging (MRI) scan analysis. MATERIALS AND METHODS: This study enrolled patients with active moderate-to-severe RA who displayed an inadequate response to oral MTX at screening. Patients were assigned to receive either MTX plus ETN or MTX monotherapy (≥10 mg/week). The primary endpoint was the quantitative knee cartilage volume using our software developed for MRI scan analysis. RESULTS: A total of 18 female patients were enrolled in this study and allocated to the MTX + ETN group (n = 9) or the MTX monotherapy group (n = 9). At 52 weeks, the quantitative knee cartilage volume was significantly reduced compared with baseline in both groups (MTX plus ETN group: 2.3 ± 2.3 cm3; MTX monotherapy group: 2.4 ± 1.6 cm3); however, the difference was not significant. CONCLUSION: The semi-automated software for MRI scan analysis can reveal useful and potentially clinically important information about the characteristics of knee joint destruction in patients with RA.

Relationship between roentgenographic joint destruction in the hands and functional disorders among patients with rheumatoid arthritis.

OBJECTIVES: Although a relationship between joint destruction and functional disorders seems apparent in patients with rheumatoid arthritis (RA), it has not been well proven in the literature. The aims of this study were to clarify the relationship between roentgenographic joint destruction in the hands and functional disorders in patients with RA, and to explore the appropriate assessment measures for functional disorders. METHODS: Cross-sectional data of the Genant-modified Total Sharp Score (Genant-mTSS), Health Assessment Questionnaire-Disability Index (HAQ-DI), Disabilities of the Arm, Shoulder, and Hand (DASH), and Michigan Hand Outcomes Questionnaire (MHQ) were collected from 50 consecutive RA patients and analyzed. RESULTS: HAQ-DI, DASH, and MHQ had close correlations with Genant-mTSS, with correlation coefficients of 0.69, 0.71, and -0.70, respectively, among patients with low disease activity (DAS28 < 3.2). A floor effect was observed in HAQ-DI, but neither floor nor ceiling effects were observed in DASH and MHQ. Both DASH and MHQ were strongly correlated with HAQ-DI, with correlation coefficients of 0.87 and 0.73, respectively. CONCLUSIONS: Functional disorders had significant relationships with roentgenographic joint destruction in the hands among RA patients with low disease activity. As assessment measures of functional disorders, DASH and MHQ had no floor or ceiling effects, being different from HAQ-DI.

Time trends and risk factors for perioperative complications in total ankle arthroplasty: retrospective analysis using a national database in Japan.

BACKGROUND: Total ankle arthroplasty (TAA) has become increasingly popular worldwide as an alternative to ankle arthrodesis for surgical treatment of end-stage ankle arthritis. The aim of this epidemiological study, using a national inpatient database in Japan, was to describe the volume, utilization, patient characteristics, and temporal trends regarding these procedures in Japan, and to identify the risk factors associated with perioperative adverse events in TAA. METHODS: This was a population-based, retrospective cohort study. We retrospectively identified 2775 patients in the Diagnosis Procedure Combination database who underwent ankle arthrodesis or TAA for ankle arthritis at 559 hospitals in Japan from 2007 to 2013. Information on sex, age, main diagnosis, use of blood transfusion, duration of anesthesia, length of hospital stay, in-hospital mortality, hospitalization costs, additional procedures after primary surgery, and use of negative pressure wound therapy was extracted. Multivariable logistic regression analysis was performed to analyze the effect of various factors on the incidence of perioperative adverse events in TAA, including additional procedure during hospitalization, negative pressure wound therapy, blood transfusion, and in-hospital death. RESULTS: We identified 465 patients who underwent TAA and 2310 patients who underwent ankle arthrodesis. There was no apparent increase in the proportion of TAAs performed during the survey period. Patients undergoing TAA tended to be older, female, and have rheumatoid arthritis compared with those undergoing ankle arthrodesis. Patients undergoing TAA had shorter length of stay, higher hospitalization costs, and more blood transfusions compared with those undergoing ankle arthrodesis. Lower hospital volume and shorter anesthesia time were associated with higher rates of adverse events after TAA. CONCLUSIONS: Despite an increase in the popularity of TAA internationally, the number of TAAs performed remains low in Japan. Lower hospital volume and anesthesia time were associated with higher rates of perioperative adverse events after TAA. LEVEL OF EVIDENCE: IV, Cross-sectional study.

Total Talar Replacement for Idiopathic Necrosis of the Talus: A Case Report.

Idiopathic osteonecrosis of the talus is a rare but severe condition that directly affects the ability to walk and is difficult to treat either conservatively or surgically. We report the case of a 72-year-old female with idiopathic necrosis of the talus treated with total talar replacement surgery. A custom-made aluminum-ceramic total talar prosthesis was prepared using the mirror image of the computed tomography and radiographic data from the contralateral ankle. The talus was exposed and removed using an anterior approach, and the total talar prosthesis was inserted. The prosthesis was placed in a stable position between the tibia, calcaneus, and navicular, with no signs of instability with ankle joint movement. The ankle was immobilized in a short-leg cast for 3 weeks. At the latest follow-up examination, 2 years after surgery, the patient was walking without pain. Examination of the left ankle showed 20° of dorsiflexion and 40° of plantar flexion. The American Orthopaedic Foot and Ankle Society ankle/hindfoot score was 90, which had improved from a preoperative score of 45. Radiographic examination showed that the prosthesis was in a stable position in the ankle mortise, and no degenerative or destructive changes were observed in the surrounding bones. This is the first reported case of total talar replacement with a prosthesis for idiopathic talar necrosis. Although the long-term outcome is still unknown, this procedure could provide a good treatment option for idiopathic necrosis of the talus.

The impact of joint disease on the Modified Health Assessment Questionnaire scores in rheumatoid arthritis patients: A cross-sectional study using the National Database of Rheumatic Diseases by iR-net in Japan.

OBJECTIVES: To investigate the effect of bilateral and unilateral joint disease on the Modified Health Assessment Questionnaire (MHAQ) scores and the differences in joint weighting in rheumatoid arthritis patients. METHODS: A total of 9212 subjects from the Japanese nationwide cohort database NinJa, 2011, were analyzed. The presence or absence of disease in each joint, including swelling and/or tenderness, was investigated. The correlations between bilateral and unilateral disease in each joint and MHAQ scores were investigated using multivariable logistic regression analysis. RESULTS: The patients' mean age and disease duration was 63.2 and 12.2 years, respectively. The Disease Activity Score-28 was 3.3. The odds ratios of physical impairment according to the MHAQ using multivariable logistic regression models for bilateral and unilateral joints, respectively, were: shoulder, 4.0 and 1.8; elbow, 2.6 and 1.8; wrist, 1.9 and 1.5; hip, 1.7 and 3.0; knee, 2.6 and 1.9; ankle, 2.3 and 2.0, finger, 1.4 and 1.2; and toe, 1.0 and 1.1. The shoulder, elbow, wrist, knee, and ankle had a significant effect on physical impairment. CONCLUSIONS: The MHAQ score was significantly affected by shoulder, elbow, wrist, knee, and ankle joint disease. Furthermore, bilateral disease tended to have a greater effect on physical impairment than unilateral disease.

Prevalence of total knee arthroplasty and its predictive factors in Japanese patients with rheumatoid arthritis: Analysis using the NinJa cohort.

OBJECTIVES: The aim of this study was to clarify the prevalence and the predictive factors for undergoing total knee arthroplasty (TKA) among patients with rheumatoid arthritis (RA). METHODS: The data of 1,134 patients with RA who were enrolled in the Japanese nationwide cohort database NinJa in 2003 and consecutively followed up until 2009 were analyzed. RESULTS: Seventy-six patients underwent TKA during the observation period. The yearly progression of the modified Health Assessment Questionnaire or mHAQ score from 2003 to 2004, but not the yearly progression of the Disease Activity Score in 28 Joints or DAS28 or patient visual analog scale (VAS) score, was significantly higher in the patients who underwent TKA than those who did not. Multivariate analysis showed that knee involvement in the disease, high Steinbrocker stage (III or IV), and high patient VAS score at the time of enrollment were powerful predictive factors, with hazard ratios of 4.01, 3.71, and 1.20, respectively. According to survival analysis with TKA as an endpoint, patients with knee involvement in the disease at the time of enrollment had a significantly worse 5-year survival rate than did those without knee involvement (83.5% vs. 97.0%, respectively). CONCLUSION: Several factors were elucidated as predictive factors for undergoing TKA among patients with RA.

Global epigenomic analysis indicates protocadherin-7 activates osteoclastogenesis by promoting cell-cell fusion.

Gene expression is dependent not only on genomic sequences, but also epigenetic control, in which the regulation of chromatin by histone modification plays a crucial role. Histone H3 lysine 4 trimethylation (H3K4me3) and histone H3 lysine 27 trimethylation (H3K27me3) are related to transcriptionally activated and silenced sequences, respectively. Osteoclasts, the multinucleated cells that resorb bone, are generated by the fusion of precursor cells of monocyte/macrophage lineage. To elucidate the molecular and epigenetic regulation of osteoclast differentiation, we performed a chromatin immunoprecipitation sequencing (ChIP-seq) analysis for H3K4me3 and H3K27me3 in combination with RNA sequencing. We focused on the histone modification change from H3K4me3(+)H3K27me3(+) to H3K4me3(+)H3K27me3(-) and identified the protocadherin-7 gene (Pcdh7) to be among the genes epigenetically regulated during osteoclastogenesis. Pcdh7 was induced by RANKL stimulation in an NFAT-dependent manner. The knockdown of Pcdh7 inhibited RANKL-induced osteoclast differentiation due to the impairment of cell-cell fusion, accompanied by a decreased expression of the fusion-related genes Dcstamp, Ocstamp and Atp6v0d2. This study demonstrates that Pcdh7 plays a key role in osteoclastogenesis by promoting cell-cell fusion.

Vertebral fractures affect functional status in postmenopausal rheumatoid arthritis patients.

Functional disability is a major concern in patients with rheumatoid arthritis (RA). This retrospective study investigated the risk factors for vertebral fractures (VFs) in postmenopausal RA patients and determined the impact of VFs on functional status. Data from a cohort of 200 postmenopausal RA patients in a single hospital registry were analyzed. Demographic and clinical data, imaging data from spine radiographs, and bone mineral density (BMD) data were collected from the patients at baseline and at the final visit (a mean of 2.9 years after the first visit). Risk factors for incident VFs and their impact on the modified health assessment questionnaire (mHAQ) were analyzed. Twenty-eight patients (14%) developed new VFs (NVFs). Logistic regression analysis adjusted for age, BMI, and disease duration revealed that daily dose of prednisolone, femoral neck BMD, use of active vitamin D3, and use of a bisphosphonate at baseline were factors associated with NVF, with odds ratios (95% confidence interval) of 1.27 (1.05-1.54), 0.94 (0.91-0.97), 0.34 (0.13-0.89), and 0.31 (0.12-0.82), respectively. Patients with NVF exhibited worse mHAQ scores and a greater increase in mHAQ scores from baseline compared with those without NVF. In conclusion, incident VFs were associated with reduced functional status in postmenopausal patients with RA. It is important to prevent VFs to maintain the functional status of RA patients.

Midterm results of resection arthroplasty for forefoot deformities in patients with rheumatoid arthritis and the risk factors associated with patient dissatisfaction.

We investigated the midterm results of resection arthroplasty of all 5 metatarsal heads in patients with rheumatoid arthritis and forefoot deformity and analyzed the factors that affect patient satisfaction levels. Of 64 patients (1 male, 63 females), 107 feet were treated with resection arthroplasty for forefoot deformity at our hospital from January 1992 to December 2005. The mean follow-up period was 5.8 ± 3.1 years, with all patients having at least 1 year of follow-up. Of the 64 patients, 75% were satisfied with the surgery. The mean score for the postoperative Japanese Society for Surgery of the Foot lesser metatarsophalangeal-interphalangeal scale was 75.0 ± 15.8 points. Multivariate logistic regression analysis showed that patient-reported dissatisfaction was significantly associated with the recurrence of hammer toe deformity (odds ratio 2.66, 95% confidence interval 1.07 to 6.97), shortening of the resection arthroplasty space (odds ratio 0.85 for a 1-unit increase, 95% confidence interval 0.74 to 0.96), and the recurrence of hallux valgus (odds ratio 1.04 for a 1-unit increase, 95% confidence interval 1.00 to 1.09) during the postoperative period. From our results, interventions to prevent recurrence of hammer toe deformity, especially in toes with preoperative metatarsophalangeal joint dislocations, have been shown to be important in preventing complications and patient dissatisfaction after resection arthroplasty.

Smart insole-based analysis of gait biomechanics for insoles in patients with flatfoot.

BACKGROUND: Assessing the effect of insoles on gait biomechanics and foot comfort remains challenging. Our novel in-insole-type wearable sensor device (smart insole) enables accurate quantitative evaluation of gait parameters without affecting the subject's foot comfort. RESEARCH QUESTION: What are the effects of insoles on gait biomechanics and foot comfort in patients with flatfoot, as evaluated using a novel smart insole? METHODS: Thirty-three subjects with 61 flatfeet were recruited. Three different types of prefabricated insoles were tested: a control insole as an experimental control, a flat insole with only cushion pads for the shock absorbing function, and an arch support insole with both cushioning pads and arch support functions. Gait parameters and visual analog scale (VAS) scores for foot comfort were measured during 30 m of straight walking with each insole incorporating the wearable sensor device. The differences in gait parameters and foot comfort between the flat and arch support insoles relative to the control insole were analyzed. Additionally, the correlations between gait parameters and foot comfort were evaluated. RESULTS: Maximum plantarflexion angle significantly decreased (p = 0.03) and the toe-out angle significantly increased (p < 0.01) with arch support insoles compared to flat insoles. Significantly better foot comfort was demonstrated when walking with arch support insoles than with flat insoles (p < 0.01). The only gait parameter correlated with foot comfort was foot lift height while walking with an arch support insole (r = -0.45, p < 0.01). SIGNIFICANCE: A novel smart insole revealed that foot lift height was a key gait parameter for determining foot comfort while walking with an arch support insole. Our findings provide important evidence for selecting a comfortable flatfoot insole based on gait data measured using a smart insole.

Patellar fracture after total knee arthroplasty for rheumatoid arthritis.

Patellar fracture is one of the most challenging complications of total knee arthroplasty, but relatively, little is known about it in patients with rheumatoid arthritis. We retrospectively analyzed 329 total knee arthroplasties performed in 230 female patients with rheumatoid arthritis to identify the incidence and risk factors for postoperative patellar fractures. The mean age was 61.8 years, and the mean follow-up period was 6.2 years. Patellar resurfacing was performed in all cases. Five postoperative patellar fractures (1.51%) were identified, and a thin residual patellar thickness and the use of posterior-stabilizing components were identified as significant risk factors, although the number of fractures was small in both groups. There was also tendency of higher age and greater joint line change observed in patients with fracture compared with those without fracture.