Referential values for lower limb flexibility in healthy children and adolescents in Japan: A five-year cross-sectional study

BACKGROUND

Lower limb flexibility (LLF) is an essential motor function. However, assessing LLF during adolescence is difficult because of the influence of marked physical changes. We, therefore, assessed LLF and investigated the relationship between LLF and sex and age in healthy children and adolescents.

METHODS

We conducted a five-year cross-sectional study with students aged 8-14 years at a single school in Japan. We evaluated the heel-buttock distance (HBD), straight leg raising angle (SLRA), and dorsiflexion angle of the ankle joint (DFA) at the beginning of each year. We conducted a comparative analysis on the performance of the HBD, SLRA, and DFA techniques, stratified by both sex and age. The statistical significance of observed differences was assessed through the application of Mann-Whitney U and Kruskal-Wallis tests. Furthermore, we analyzed the effects of sex, age, height, and weight on LLF using a multivariable linear regression model.

RESULTS

Of the 4221 initial study participants, 3370 were analyzed. Mean HBD, SLRA, and DFA values were 1.6 cm, 77.0°, and 15.7°, respectively. Girls showed significantly higher HBD and lower SLRA and DFA values than boys and 14-year-olds (p < 0.01). Median HBD value for girls was 0 cm, whereas for boys, it exceeded 0 cm after age 13. The median SLRA value for girls was 80-85°, while for boys, it was 70-75°. The median DFA value for girls was 15-19°, and for boys, it was 12-15°. A multivariable linear regression model indicated that boys had significantly greater tightness than girls (p < 0.01).

CONCLUSIONS

The reference values of HBD, SLRA, and DFA differed according to age and sex. Furthermore, we showed that sex differences were significantly associated with LLF. Data in this study provide the reference value for assessing LLF in children and adolescents.

Number of intra-operative cyclic knee motion required to achieve stable graft tension in anterior cruciate ligament reconstruction; a prospective clinical study

BACKGROUND

Applying pretension by cyclic knee motion immediately before graft fixation in anterior cruciate ligament (ACL) reconstruction surgery decreases graft elongation during the postoperative course. However, the expected change in graft tension caused by cyclic knee motion remains unclear. We measured graft tension changes caused by cyclic knee motion during double-bundle ACL reconstruction.

METHODS

We included 39 patients undergoing primary anatomical double-bundle ACL reconstruction with autologous hamstrings as graft sources, at multiple centers between February 2021 and August 2022. After securing the anteromedial (AM) and posterolateral (PL) bundle grafts to the femoral cortex, they were initially tensioned to 40 N per bundle. After 10 cycles of knee extension and flexion motion, ranging from 0 to 90-110°, tension was re-measured and re-tensioned to 40 N if the graft tension had decreased. This was repeated thrice for 10 cycles on each graft. Every 10 cycles, we recorded graft tension changes (ΔGT) and compared the mean ΔGT in the AM and PL bundles. Furthermore, we assessed relationships between total ΔGT in each bundle, age, sex, and graft diameter.

RESULTS

Twenty-five women and 14 men with a mean age of 27.4 ± 12.4 years were included. The mean ΔGT in AM and PL bundles after every 10 cycles were 6.6 ± 3.7 N, 3.0 ± 2.3 N, 1.4 ± 1.5 N, and 9.9 ± 3.8 N, 4.9 ± 2.6 N, and 2.5 ± 1.9 N, respectively. There were significant differences in ΔGT in both bundles after every 10 cycles (p < 0.01). ΔGT in the AM bundle was significantly lower than in the PM bundle at the same number of cycles (p < 0.01). No correlation was observed between ΔGT in either bundle and age, sex, or graft diameter.

CONCLUSIONS

The initially applied graft tension decreased by intra-operative cyclic knee movement, and the changes in graft tension decreased after retention and repeated cycles. Three sets of 10 cycles knee motion may avoid initial tension loss of the hamstring autograft in the early phase after double-bundle ACL reconstruction.

Variability in sonographic anterior drawer test measurements of the ankle: Experienced versus beginner examiners

BACKGROUND

This study aimed to clarify the variability in the measurements of stress sonography of the ankle and determine the effects of examiner experience on the measurements.

METHODS

Twenty examiners (10 experienced and 10 beginners) were included in the study. Each examiner performed stress ultrasonography on a patient with a chronic anterior talofibular ligament injury and a patient with an intact ligament using the reverse anterior drawer method. Changes in ligament length before versus after stress were determined. The same 20 examiners performed ultrasonography on two other patients with an injured or intact ATFL using the anterior drawer method. The length change values and variance were compared between the groups using t-tests and F-tests.

RESULTS

Using the reverse anterior drawer method, the change in the anterior talofibular ligament length was 3.3 mm (range, 2.2-4.8 mm) in the experienced group and 2.7 mm (0.0-4.1 mm) in the beginner group for the ligament injured patient. The length changes for the patient with intact anterior talofibular ligament were 0.5 mm (0.1-0.9 mm) and 0.4 mm (-0.1-1.5 mm) in the experienced and beginner groups, respectively. There were no significant intergroup differences in measurement amount (P = 0.37) or variance (P = 0.72). Similarly, using the anterior drawer method, no significant differences between the groups were found in measurement amount or variance.

CONCLUSION

The quantitative evaluation of stress sonography of the ankle was variable regardless of examiner experience or stress method, particularly in patients with an anterior talofibular ligament injury. The amount of variability appeared to be unacceptably large for clinical application. Our study results highlight the need for technical standardization.

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.

Impact of the COVID-19 Pandemic on Injury Incidence in Japanese Male Professional Soccer Players

Background

The outbreak of the 2019 novel coronavirus disease (COVID-19) led to an enforced quarantine period and limited training and match activities for athletes.

Purpose

To report the influence of the COVID-19 pandemic on the occurrence of injury in Japanese male professional soccer players.

Study Design

Descriptive epidemiology study.

Methods

In total, 21 clubs in the 2019 season and 28 clubs in the 2020 season from the Japan Professional Football League were prospectively followed, and 16 clubs in 2019 and 24 clubs in 2020 were analyzed in this study. Individual training, match exposure, and time-loss injuries were recorded using an electronic data capture system. The influence of COVID-19-related suspension during the 2020 season was retrospectively investigated via comparisons with the 2019 season.

Results

Total activity time included 114,001 hours in training and 16,339 hours in matches in 2019 and 170,798 hours in training and 25,411 hours in matches in 2020. The mean training interruption period caused by COVID-19 in 2020 was 39.9 days (range, 3-65 days), and the mean game-interruption period was 70.1 days (range, 58-79 days). The total number of injuries was 1495 in 2019 and 1701 in 2020. The overall injury incidence per 1000 hours of exposure was 5.7 in 2019 and 5.8 in 2020. The overall injury burden per 1000 hours of exposure was 155.5 days in 2019 and 130.2 days in 2020. The muscle injury incidence was highest in May 2020, immediately after the suspension period.

Conclusion

The overall injury incidence did not differ between 2019 and 2020. However, muscle injury incidence notably increased in the 2 months after the COVID-19 pandemic suspension period.

Foot morphology and correlation with lower extremity pain in Japanese children: A cross-sectional study of the foot posture Index-6

BACKGROUND

Abnormal foot morphology in children and adolescents is a possible risk factor for lower extremity pain. Foot posture index-6 (FPI-6) is a valid and reliable tool to assess foot morphology. However, the normative data on the age distribution for FPI-6 in Asian children and adolescents are still minimal. Further, the correlation of FPI-6 with lower extremity pain is poorly understood. We aimed to investigate the normative distribution for FPI-6 and the relationship between FPI-6 scores and knee and heel pain in Japanese children.

METHODS

We included 2569 Japanese children, aged 9-15 years, at a single school from 2016 to 2018. We summarized the age distribution of children and their mean bilateral FPI-6 scores. Additionally, we assessed the tenderness at the apophysis or tendon insertions at the knee and heel. We performed a cross-sectional analysis to investigate the correlations between FPI-6 scores and sex, age, and knee and heel pain for the data obtained each year.

RESULTS

The mean FPI-6 score was 3.1 ± 2.4, 3.4 ± 2.0, and 3.2 ± 1.9 for the left foot and 3.0 ± 2.4, 3.2 ± 1.9, and 3.1 ± 1.9 for the right foot in 2016, 2017, and 2018, respectively. Boys tended to have higher scores than girls, and the FPI-6 score of the left foot was significantly higher than that of the right foot (p < 0.05). There was no correlation between FPI-6 scores and knee and heel pain.

CONCLUSION

Children and adolescents between 9 and 15 years of age have neutral to slightly pronated foot morphology and an average FPI-6 score of 3.0-3.4. In addition, there was no relationship between foot morphology and knee and heel pain. This normative distribution for FPI-6 in Japanese children could serve as a reference value for future research and clinical evaluation.

Nuclear receptor subfamily 1 group D member 1 in the pathology of obesity-induced osteoarthritis progression

Mechanical overload and chemical factors are both related to obesity-induced progression of knee osteoarthritis. The circadian rhythm is related to the development of metabolic syndrome and the progression of osteoarthritis, and the core clock genes nuclear receptor subfamily 1 group D member 1 (NR1D1) and brain and muscle arnt-like protein 1 (BMAL1) are dysregulated in cartilage from patients with osteoarthritis. Here, we focused on NR1D1 and investigated osteoarthritis-related changes and gene expression in a mouse model of diet-induced obesity. A high-fat diet was provided to C57BL6/J mice, and changes in body weight, blood lipids, and gene expression were investigated. Destabilization of the medial meniscus or sham surgery was performed on mice fed a high-fat diet or normal diet, and histological osteoarthritis-related changes and NR1D1 expression were investigated. The effects of the NR1D1 agonist SR9009 were also assessed. Mice fed a high-fat diet developed significant obesity and dyslipidemia. Nr1d1 and Bmal1 gene expression levels decreased in the liver and knee joints. Moreover, increased osteoarthritis progression and decreased NR1D1 protein expression were observed in high-fat diet-fed mice after surgical osteoarthritis induction. SR9009 decreased the progression of obesity, dyslipidemia, and osteoarthritis. Overall, obesity and dyslipidemia induced by the high-fat diet led to osteoarthritis progression and decreased NR1D1 expression. Thus, NR1D1 may play an important role in obesity-induced osteoarthritis.

Cross-cultural Adaptation and Validation of the Japanese Version of the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS)

Background:

The Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) is a specifically designed scoring system for children and has been translated into several languages. However, to date, no validated Japanese version of this scoring system is available.

Purpose:

To translate the HSS Pedi-FABS into Japanese and assess its reliability and validity.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

The HSS Pedi-FABS was translated into Japanese and back-translated into English to confirm the appropriateness of the translation. A total of 764 children aged 9 to 15 years participated in the validation study. The participants answered the Japanese version of the HSS Pedi-FABS along with 2 other questionnaires in Japanese (the Physical Activity Questionnaire for Older Children [PAQ-C] and the physical activity questionnaire of the World Health Organization’s Health Behavior in School-aged Children [HBSC PAQ]). At 1 month after the first assessment, the children answered the Japanese version of the HSS Pedi-FABS again. We evaluated reliability using the Cronbach alpha and the intraclass correlation coefficient. Validity was evaluated by quantifying floor and ceiling effects, correlations between the HSS Pedi-FABS and the PAQ-C, the HSS Pedi-FABS discrepancy between active and inactive groups divided by the HBSC PAQ, and correlation between the HSS Pedi-FABS and body mass index.

Results:

HSS Pedi-FABS scores were slightly but significantly higher in male participants (mean = 16.7) than in female participants (mean = 13.2). The Cronbach alpha coefficient was .90, and the intraclass correlation coefficient value was 0.90, indicating excellent internal consistency and test-retest reliability, respectively. No floor (2.6%) or ceiling effect (1.0%) was observed. The HSS Pedi-FABS was significantly correlated with the PAQ-C (r = 0.70). The active group demonstrated a significantly higher score on the HSS Pedi-FABS (mean = 18.9) than did the inactive group (mean = 11.2). In terms of discriminative validity, the HSS Pedi-FABS was not correlated with body mass index (r = –0.15).

Conclusion:

The Japanese version of the HSS Pedi-FABS demonstrated appropriate reliability and validity, indicating that it is a useful tool to assess physical activity levels in Japanese children.

Time-Dependent Change in Cartilage Repair Tissue Evaluated by Magnetic Resonance Imaging up to 2 years after Atelocollagen-Assisted Autologous Cartilage Transplantation: Data from the CaTCh Study

OBJECTIVE

To elucidate the time course of magnetic resonance imaging (MRI)-based morphological and qualitative outcomes after an atelocollagen-assisted autologous chondrocyte implantation (ACI) and to analyze the correlation between arthroscopic and MRI-based assessment.

DESIGN

We included ACI recipients from a multicenter registration study (CaTCh [Cartilage Treatment in Chiba] study). Morphological (3-dimensional magnetic resonance observation of cartilage repair tissue: 3D-MOCART, MOCART2.0) and qualitative assessment (T2- and T1rho-mapping) by MRI were conducted at 6, 12, and 24 months post-implantation. Global T2 and T1rho indices (T2 and T1rho in repair tissue divided by T2 and T1rho in normal cartilage) were calculated. Arthroscopic second-look assessment was performed in 4 and 15 knees at 12 and 24 months post-implantation, respectively.

RESULTS

The 3D-MOCART over 12 months witnessed significant patient improvement, but some presented subchondral bone degeneration as early as 6 months. The MOCART2.0 improved from 57.5 to 71.3 between 6 and 24 months (P = 0.02). The global T2 index decreased from 1.7 to 1.2 between 6 and 24 months (P < 0.001). The global T1rho index decreased from 1.5 to 1.3 between 6 and 24 months (P = 0.004). Normal or nearly normal ICRS-CRA (cartilage repair assessment scale developed by the International Cartilage Repair Society) grades were achieved in 86% and 93% of the lesions at 12 and 24 months, respectively. Better ICRS-CRA grade corresponded to better MOCART2.0, with no trend in the T2 and T1rho values.

CONCLUSIONS

Atelocollagen-assisted ACI improved the MRI-based morphological and qualitative outcomes until 24 months post-surgery, and normal or nearly normal grades were achieved in most lesions by arthroscopic assessment. MRI assessment may be an alternative to arthroscopic assessment.

The influence of COVID-19 pandemic on the incidence of knee pain and physical activity level in children and adolescents in Japan: A prospective observation study

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has had a profound impact on children's lifestyles. Some studies have reported psychological changes in children after the pandemic, but information on musculoskeletal problems is scarce. This study aimed to investigate the incidence of knee pain and changes in physical activity after the spread of COVID-19 among elementary and junior high school students in Japan.

METHODS

Knee pain and amount of physical activity were recorded on a monthly basis between August 2019 and February 2021 in children aged 8-14 years using a self-administered questionnaire. The amount of physical activity was scored using the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS). The period until February 2020 was defined as "Before pandemic," and the period from March 2020 was defined as "After pandemic." The incidences of knee pain and HSS Pedi-FABS scores before and after the COVID-19 pandemic were compared. Additionally, we compared the prevalence of knee pain and HSS Pedi-FABS scores according to sex and age.

RESULTS

We enrolled 886 and 881 participants before and after the pandemic, respectively. The prevalence of knee pain among the participants before and after the pandemic was 6.7% and 7.9%, respectively (p = 0.032). The mean HSS Pedi-FABS scores before and after the pandemic were 14.8 and 14.5, respectively (p = 0.005). Participants aged 14 years had a significantly lower incidence of knee pain (p = 0.013) and significantly higher HSS Pedi-FABS scores (p < 0.001) after the spread of COVID-19.

CONCLUSIONS

In elementary and junior high school students, increase in the incidence of knee pain and decrease in the amount of physical activity after the spread of COVID-19 were observed.

Automated detection of anterior cruciate ligament tears using a deep convolutional neural network

Background

The development of computer-assisted technologies to diagnose anterior cruciate ligament (ACL) injury by analyzing knee magnetic resonance images (MRI) would be beneficial, and convolutional neural network (CNN)-based deep learning approaches may offer a solution. This study aimed to evaluate the accuracy of a CNN system in diagnosing ACL ruptures by a single slice from a knee MRI and to compare the results with that of experienced human readers.

Methods

One hundred sagittal MR images from patients with and without ACL injuries, confirmed by arthroscopy, were cropped and used for the CNN training. The final decision by the CNN for intact or torn ACL was based on the probability of ACL tear on a single MRI slice. Twelve board-certified physicians reviewed the same images used by CNN.

Results

The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the CNN classification was 91.0%, 86.0%, 88.5%, 87.0%, and 91.0%, respectively. The overall values of the physicians’ readings were similar, but the specificity was lower than the CNN classification for some of the physicians, thus resulting in lower accuracy for the human readers.

Conclusions

The trained CNN automatically detected the ACL tears with acceptable accuracy comparable to that of human readers.

Knowledge of and experience with transgender players among soccer team staff: a cross-sectional questionnaire design

OBJECTIVES

Transgender issues have become increasingly prominent in sports. However, knowledge of and experience with supporting transgender players across soccer team staff remain unclear. The objectives of this questionnaire-based study were to 1) clarify staff knowledge of transgender-related terminology; and 2) explore soccer team staff's awareness and experience with supporting transgender players.

METHODS

A questionnaire was distributed to coaches, physicians, and physical trainers affiliated with soccer teams between 2018 and 2019 to capture 1) participant characteristics (e.g. gender, age, certified license, team categories); 2) their understanding of transgender-related terms, including lesbian, gay, bisexual, and transgender (LGBT) and of the IOC Consensus Meeting on Sex Reassignment and Hyperandrogenism in 2015; 3) their awareness of transgender players; and 4) their experience supporting transgender players. Participants were categorized by age, gender, profession, qualifications, and category of involvement; their understanding and experience were investigated statistically using univariate and multivariate analysis.

RESULTS

The 478 respondents included 30 women and 448 men with a mean age of 38 ± 10 years. Of these, 83% understood the term transgender, 75% understood the term LGBT, while only 7% were familiar with the 2015 IOC Consensus Meeting. Physicians reflected more knowledge than coaches and physical trainers (p < 0.01). Altogether, 15% had identified transgender players and 1% had experience supporting them. Respondents with certified licenses who worked with women's teams were more likely to recognize transgender players (p < 0.01). Four participants (1%) had witnessed transgender players receiving transgender hormone therapy.

CONCLUSION

Although most soccer support staff were familiar with transgender terms, many did not have sufficient knowledge of or experience with transgender athletes.

Risk factors for the occurrence and protraction of patellar and patellar tendon pain in children and adolescents: a prospective cohort study of 3 years

Background

Patellar and patellar tendon pain is a common limitation to children’s participation in social and physical activities. Some factors have been implicated in the occurrence and protraction of knee pain, but the causal relationship is unknown. The purpose of this study was to investigate whether participants’ physical characteristics and activity level are risk factors for the occurrence and protraction of patellar and patellar tendon pain in children and adolescents.

Methods

A three-year prospective cohort study was conducted with healthy students who were aged 8–14 years old, in Japan. Height, weight, heel-buttock distance, straight leg raising angle, and dorsiflexion angle of the ankle joint were collected as individual physical factors at the beginning of each year. The presence of self-reported patellar and patellar tendon pain and the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) was collected every month. Protraction was defined as either (1) pain lasting for more than three continuous months or (2) recurrent pain after more than three months of complete recovery. Participants who did not have any pain at the beginning of the observation period were included in the analysis. We analyzed the odds ratio (OR) of pain occurrence within a year of registration and protraction throughout the study period for all physical factors and HSS Pedi-FABS.

Results

We included 1133 participants in the analysis and 252 participants developed knee pain within a year. 34.8% of participants with pain experienced protraction during the follow-up period. A high HSS Pedi-FABS significantly predicted knee pain occurrence (OR 1.03, 95% confidence interval [CI] 1.01–1.05) and protraction (OR 1.03, 95% CI 1.00–1.05). In addition, younger children and girls were at a significantly higher risk of patellar and patellar tendon pain protraction (age, OR 0.81, 95% CI, 0.73–0.90; sex, OR 1.69, 95% CI, 1.09–2.64). Other physical factors did not significantly predict the occurrence or protraction of knee pain.

Conclusions

This study showed that a greater physical activity level was a risk factor for the occurrence and protraction of patellar and patellar tendon pain in childhood. In addition, younger age and female sex predicted higher risk of protraction of pain.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05349-y.

Anatomical factors associated with progression of hallux valgus

BACKGROUND

The purpose of this study was to clarify the incidence rate and the risk factors for the progression of the hallux valgus deformity.

METHODS

Patients who had weight-bearing radiographs of the foot taken twice or more, with a ≥2-year interval, were retrospectively analyzed. Progression of the deformity was defined as an increase in the hallux valgus angle of ≥5° during the follow-up. The association of hallux valgus progression with patient characteristics and radiographic measurements at baseline was determined using univariate and multivariate analyses.

RESULTS

Totally, 268 patients (217 women and 51 men; median age, 64 years) were analyzed. An increase in the hallux valgus angle of ≥5° occurred in 44 (17%) patients in a median follow-up of 49 months. Large hallux valgus angle (odds ratio, 1.07) on the dorsoplantar radiograph at baseline were independent risk factors for the progression of the deformity.

CONCLUSION

Progression of the hallux valgus deformity occurred in one of six patients. Furthermore, large hallux valgus angle was the risk factor for subsequent deformity progression. Patients with large hallux valgus angle should be informed about the possible progression of the deformity.

Effect of Systemic Administration of Granulocyte Colony-Stimulating Factor on a Chronic Partial-Thickness Cartilage Defect in a Rabbit Knee Joint

OBJECTIVE

Cartilage lesions in the knee joint can lead to joint mechanics changes and cause knee pain. Bone marrow stimulation (BMS) promotes cartilage regeneration by perforating the subchondral bone just below the injury and inducing bone marrow cells. This study aimed to investigate whether systemic administration of granulocyte colony-stimulating factor (G-CSF) with BMS improves repair of chronic partial-thickness cartilage defects (PTCDs).

DESIGN

Eighteen 6-month-old New Zealand white rabbits were divided into 3 groups: control (C, n = 6), BMS alone (n = 6), and BMS + G-CSF (n = 6). Partial cartilage defects with 5 mm diameter were created in the trochlear region of both knees; after 4 weeks, the BMS alone and BMS + G-CSF groups underwent BMS; G-CSF (50 µg/kg) or saline was administered subcutaneously for 5 days starting from 3 days before BMS. At 8 and 16 weeks after cartilage defect creation, the area of cartilage defects was macroscopically and histologically evaluated.

RESULTS

International Cartilage Repair Society (ICRS) grades for macroscopic assessment were 0, 0.7, and 0.7 at 8 weeks and 0, 1.2, and 1.3 at 16 weeks in the C, BMS, and BMS + G-CSF groups, respectively. Wakitani scores for histological assessment were 9.8, 8.7, and 8.2 at 8 weeks and 9.5, 9, and 8.2 at 16 weeks in the C, BMS, and BMS + G-CSF groups, respectively. The BMS + G-CSF group showed significantly more repair than the C group, but there was no difference from the BMS group.

CONCLUSIONS

The effect of BMS and G-CSF on chronic PTCDs in mature rabbit knees was limited.

Increase in Achilles Tendon Rupture Surgery in Japan: Results From a Nationwide Health Care Database

Background:

Nationwide epidemiologic studies in Scandinavian countries have shown that the incidence of Achilles tendon ruptures (ATRs) has increased, and the rate of surgical treatment has declined markedly in the past decade. However, there is a lack of national-level data on the trend of ATRs and surgical procedures in other regions.

Purpose:

To clarify the trend in the incidence of ATRs and the proportion of surgery using the nationwide health care database in Japan.

Study Design:

Descriptive epidemiology study.

Methods:

Age- and sex-stratified data on the annual number of ATRs and surgical procedures between 2010 and 2017 were obtained from the Japanese national health care database, which includes almost all inpatient and outpatient medical claims nationwide. The Japanese population data were also obtained from the population census. The change in the annual incidence of ATRs per 100,000 people was assessed using a Poisson regression analysis. The trend in the annual proportion of surgeries relative to the occurrence of tendon ruptures was determined using a linear regression analysis.

Results:

A total of 112,601 ATRs, with men accounting for 67%, were identified over 8 years. Patients aged ≥60 years accounted for 27,106 (24%), while those aged 20 to 39 years and 40 to 59 years accounted for 36,164 (32%) and 49,331 (44%), respectively. The annual incidence of ATR ranged from 12.8/100,000 to 13.9/100,000 (women, 8.2-8.9/100,000; men, 17.2-19.5/100,000), which did not change over the study period (P = .82). Moreover, the annual incidences did not change across sexes and age categories. The annual proportion of surgery increased significantly, from 67% in 2010 to 72% in 2017 (P = .003). The annual proportions increased across sexes and age categories except for women aged 40 to 59 years.

Conclusion:

The incidence of ATR did not change between 2010 and 2017, according to the Japanese nationwide health care database. Furthermore, the proportion of surgical treatment increased during the study period. Overall, 70% of patients underwent surgical treatment. This study suggested that the trend in ATR and surgery differed across regions.

Changes in the Syndesmotic Reduction After Syndesmotic Suture-Button Fixation for Ankle Malleolar Fractures: 1-Year Longitudinal Evaluations Using Computed Tomography

BACKGROUND

Evaluation over time is important in assessing the reduction of the syndesmosis after suture-button fixation for ankle malleolar fractures. The purposes of this study were to evaluate time-dependent change in the syndesmotic reduction immediately after suture-button fixation for ankle malleolus fractures and 1 year after surgery using computed tomography, and to investigate the reliability of the measurement values to evaluate the reduction of syndesmosis.

METHODS

We assessed 28 patients who underwent suture-button fixation for ankle fractures. Syndesmotic reduction was assessed within 2 weeks of the fracture surgery and 1 year after surgery using axial computer tomographic images. Side-to-side differences in the anterior, central, and posterior tibiofibular distances, anteroposterior fibular translation, fibular rotation, and syndesmosis area were measured.

RESULTS

The mean anterior tibiofibular distance and anteroposterior fibular translation were 1.8 mm and 1.5 mm, respectively, after syndesmotic fixation. They decreased to 1.2 mm and 0.6 mm, respectively, at 1 year after surgery (P = .03 and P = .01, respectively). The other measurement values did not change over time. The minimum detectable change in the distance of measurements was 1 mm or less.

CONCLUSION

The anterior tibiofibular distance and anteroposterior fibular translation had decreased 1 year after fixation in ankle malleolar fractures with syndesmotic suture button. Even if the fibula is posteriorly malreduced by the time computed tomography is performed immediately after surgery, the fibula may return to a good position 1 year after surgery.

LEVEL OF EVIDENCE

Level IV, case series.

Isometric exercise during immobilization reduces the time to return to play after lateral ankle sprain

[Objectives] Immobilization reduces symptoms after lateral ankle sprain but may worsen the range of motion (ROM) of the ankle and delay return to play (RTP). We aimed to elucidate the correlation between ankle ROM and time to RTP following immobilization for lateral ankle sprain and investigated if isometric exercise during immobilization would increase ROM and shorten the time to RTP. [Participants and outcome measures] Eighty-two patients with acute lateral ankle sprain were treated by a short-leg cast with or without isometric exercise and electrical muscle stimulation (EMS); intervention group or control group, respectively. The correlation between ankle ROM at cast removal and time to RTP was analyzed. The total and side-to-side ankle ROM and the time to RTP were compared between the two groups. [Results] Side-to-side difference in total ankle ROM significantly correlated with time to RTP (r = 0.38, p = 0.02). The intervention reduced the side-to-side difference in total ROM (20° versus 31°, p = 0.01) and time to RTP (46 versus 65 days, p = 0.01) compared to the control group. [Conclusion] Increased deficiency in ankle ROM led to a longer time to RTP, and isometric exercise combined with EMS during immobilization increased the total ankle ROM and shortened the time to RTP.

Randomized comparative study of suspension femoral fixation device in graft position maintenance in anterior cruciate ligament reconstruction: EndoButton CL vs TightRope RT

Background

In double-bundle anterior cruciate ligament reconstruction (ACLR), fixed-loop and adjustable-loop cortical suspensory devices are commonly used to fix the soft graft on the femoral side. However, few studies have compared in vivo elongation of the two devices. The purpose of this study was to determine whether EndoButton CL (EB) and TightRope RT (TR), the suspensory fixation devices used in ACLR, maintained their length in vivo from the time of surgery through the postoperative period in a randomized controlled trial.

Methods

This study prospectively incorporated 30 patients undergoing initial ACLR at a single center. Participants were divided into two groups using a stratified randomization method with age and sex as assignment adjustment factors. EB or TR was used for fixation of the soft graft on the femoral side. The primary endpoint was to compare the elongation distance of the suspensory device. MRIs were taken within seven days after ACLR and 3,6,12 months postoperatively and measured by a radiologist in a blinded fashion. Secondary endpoints included the side-to-side difference in anterior translation, one leg hop test (HOP index), Lachman test, lateral pivot shift test, and Lysholm score one year postoperatively.

Results

Twenty-eight patients (EB, n = 13; TR, n = 15) were followed for one year. There was no significant difference between EB and TR groups in elongation from the immediate postoperative period to 3, 6, 12 months after surgery. However, the non-inferiority of TR to EB (non-inferiority margin: 1.5 mm) was not proved by the difference in measured elongation between the two groups (TR – EB, lower 95% CI. AM: 1.80 mm; PL: 1.86 mm) at 6 months. There was no significant difference in anterior translation, HOP index, Lachman test, lateral pivot shift test, or Lysholm score.

Conclusion

EB and TR had similar graft retaining ability in vivo for 12 months, but the non-inferiority of TR against EB was not verified statistically.

Can accuracy with the iASSIST navigation be confirmed by assessment? A multi-center prospective randomized controlled trial with independent three-dimensional image assessment

BACKGROUND

iASSIST is one of the novel accelerometer-based navigation systems for total knee arthroplasty (TKA). Although the accuracy of iASSIST compared with conventional instruments has been reported, such evaluations were performed on two-dimensional (2D) images (X-rays). This multi-center prospective randomized controlled trial aimed to assess component positioning between TKA with and without iASSIST by 3D image assessment, and to clarify whether the iASSIST provides any benefit with regard to alignment accuracy.

METHODS

Eighty-three knees with primary knee osteoarthritis were enrolled in this study. iASSIST was used for distal femoral and proximal tibial resection in 42 knees (iA group) and a conventional guide was used in 41 knees (CONV group). At 6 months postoperatively, component alignment was evaluated with 3D images by the independent orthopaedic surgeons, and surgical parameters, range of motion and clinical outcomes were examined.

RESULTS

The rate of knees who have the alignment within 3° of neutral compared with the iA group and CONV group were 92.9% (39/42) vs. 87.8% (36/41) for femur and 76.2% (32/42) vs. 56.1% (23/41) for tibia in the coronal plane, respectively, whereas in the sagittal plane, the rate was 85.7% (36/42) vs. 58.5% (24/41) for femur and 83.3% (35/42) vs. 78.0% (32/41) for tibia, respectively. Compared with the CONV group, the iA group had a significantly improved femoral alignment in the sagittal plane (P = 0.006). There were no clinical or patient-reported differences at 6 months postoperatively.

CONCLUSIONS

The iASSIST provides technically high accuracy in femoral resection at TKA compared with a conventional procedure.

Intra- and inter-observer reliability of implant positioning evaluation on a CT-based three-dimensional postoperative matching system for total knee arthroplasty

Background

The evaluation of postoperative total knee arthroplasty (TKA) alignment mainly relies on measurement data obtained from plain radiographs. The aim of this retrospective observational study was to document the intra- and inter-observer reliability in assessment of TKA component positioning after surgery using a three-dimensional (3D) computed tomography (CT) image matching system.

Methods

Fourteen knees from 14 patients who received primary TKA were included, and images were analyzed by blinded readers not associated with the surgeries. The examiner digitized the reference points according to defined landmarks, and the designated size component was superimposed to the 3D reconstructed CT model for measurement. In addition to the evaluation of implant position against the coronal and sagittal lower limb mechanical axes that were defined based on bony landmarks, implant position against axes connecting implant-based reference points that are easier to indicate was evaluated.

Results

The overall intra- and inter-observer reliabilities determined by the intraclass correlation coefficients (ICC) of the implant alignment measurement for both femoral and tibial components were good (ICC > 0.60), except in the direction of femoral flexion and extension, for both mechanical and implant-based axes. The difference between implant alignment measurements according to the traditional mechanical axis and the implant-based axis ranged between means of 0.08^o and 1.70^o and were statistically significantly different.

Conclusions

The postoperative evaluation of implant position in the coronal and sagittal planes using 3D-CT image matching is reliable and has good reproducibility except for the sagittal alignment assessment of the femoral component. The measured implant position according to the traditional mechanical axis and the implant-based axis were slightly but significantly different.

In vivo kinematics of cruciate-retaining total knee arthroplasty after a change of polyethylene insert configuration

Background

To investigate in vivo kinematics of total knee arthroplasty (TKA) with the introduction of a mildly constrained (MC) type of polyethylene (PE). We compared the knee kinematics with a reported pattern after surgery using the same component with a conventionally constrained (CC) type of PE.

Methods

Finite element analysis (FEA) was performed to examine different peak stress distribution of both types of PE. For in vivo study, patients who underwent cruciate-retaining TKA using a total knee system with MC-PE were included. Fluoroscopic surveillance was used to measure the weight-bearing deep knee bend (squatting) using a two-dimensional/three-dimensional (2-D/3-D) registration technique.

Results

FEA analysis revealed the edge loading of the femoral component on PE in CC but not in MC. During the study period, 42 patients underwent TKA with MC-PE. Among them, 13 agreed to participate in the present study. In vivo kinematics analysis found that starting from an average external rotation of femur being 7.1° at 0° of flexion, the rotation slightly decreased to 6.8° at 10° of flexion, then increased with increasing knee flexion until it reached 10.8° at 80° of flexion, and finally decreased to 9.8° at 100° of knee flexion. The results indicate a modest medial pivot pattern. Although the overall pattern was similar for both MC-PE and CC-PE, a slight difference was observed. MC-PE showed a slight internal rotation of 0.3° from 0 to 10° of knee flexion, whereas CC-PE showed a gradual increase of external rotation in this range.

Conclusions

Change of configuration from CC to MC did not substantially affect in vivo kinematics of knees after TKA. Considering the theoretical wider range of allowance of rotation, MC-PE is easier for knee surgeons to use.

Arthroscopic Reduction and Internal Fixation of Posterior Cruciate Ligament Avulsion Fracture Using an Adjustable-Length Loop Device

A displaced avulsion fracture at the tibial attachment of the posterior cruciate ligament is considered an indication for surgical reduction and internal fixation because nonunion and remaining posterior instability of the knee are common consequences of conservative treatment. The problems with standard open surgical techniques are that they are relatively invasive despite the limited operative field and it is impossible to explore intra-articular lesions by the posterior approach. An arthroscopic procedure has the advantage of being minimally invasive and allowing the surgeon to detect and treat associated intra-articular injuries. We present an arthroscopic reduction-internal fixation technique using an adjustable-length loop device. A trans-septal portal is created to visualize the fracture fragment directly, and the fragment is reduced and penetrated with a cannulated drill under fluoroscopic guidance. An adjustable-length loop device is relayed from the posteromedial portal and pulled out through the fragment in an anterograde fashion, placing a button on top of the fragment. By tightening the loop, downward compression can be applied to the fragment. Overall, this technique provides good reduction and bone union, and excellent clinical outcomes, including posterior knee stability, can be achieved.

The shape of the first metatarsal head and its association with the presence of sesamoid-metatarsal joint osteoarthritis and the pronation angle

BACKGROUND

The purpose of this study was to evaluate the associations of the shape of the first metatarsal head with (1) the presence of osteoarthritis in the sesamoid-metatarsal joint and (2) the pronation angle of the first metatarsal head on foot radiographs.

METHODS

A total of 121 patients, with the mean age of 61 years, underwent weight-bearing dorsoplantar, lateral, and first metatarsal axial radiographs. The shape of the first metatarsal head's lateral edge was classified as either rounded, intermediate, or angular in shape in the dorsoplantar view. The presence of osteoarthritis in the sesamoid-metatarsal joint and the pronation angle of the first metatarsal head were assessed in the first metatarsal axial view. Other variables that could affect the first metatarsal shape, including the lateral first metatarsal inclination angle, were also assessed. Univariate and multivariate analyses were performed to determine the associations.

RESULTS

The prevalence of sesamoid-metatarsal osteoarthritis was significantly higher (77%, 27%, and 29% for rounded, intermediate, and angular, respectively, P < .001), and the metatarsal pronation angle was significantly larger (14°, 8°, and 4° for rounded, intermediate, and angular, respectively, P < .001) in feet with a rounded metatarsal head. These associations were also significant in the multiple regression analysis.

CONCLUSION

A rounded metatarsal head was associated with a higher prevalence of osteoarthritis within the sesamoid-metatarsal joint, as well as a larger first metatarsal head pronation angle. A negative round sign can be used as a simple indicator of an effective correction to the first metatarsal pronation angle during hallux valgus surgery. However, in feet with sesamoid-metatarsal osteoarthritis, surgeons will need to be cautious as overcorrection may occur.

Influence of foot position on the measurement of first metatarsal axial rotation using the first metatarsal axial radiographs

BACKGROUND

The purpose of this study was to clarify 1) the measurement error of the pronation angle using the first metatarsal axial radiograph with the pronation angle along the longitudinal axis of the first metatarsal as the reference standard, 2) the influence of variability in the foot position on the measurement error, and 3) the intra- and interrater reliability of pronation angle measurement using digitally reconstructed radiographs.

METHODS

Digitally reconstructed radiographs of the first metatarsal were generated from the computed tomography images of 10 feet without hallux valgus (non-HV group) and 10 feet with hallux valgus (HV group). In total, 135 images were created at different degrees of supination, plantarflexion, and adduction from each foot to simulate the first metatarsal axial view. Then, the pronation angle of the first metatarsal was measured. The measurement error was determined using the mean error and 95% limits of agreement. Simple linear regression analysis was used to test the correlations of the measurement error with pronation, plantarflexion and adduction angles. The intra- and interrater reliability of measurement was assessed using the intraclass correlation coefficient and minimum detectable change values.

RESULTS

The mean measurement errors were 0.1° for both the non-HV and HV groups. There was no significant correlation of the measurement error with pronation, plantarflexion or adduction angles for both groups. Additionally, the intraclass correlation coefficients for the intra- and interrater reliability were more than 0.9 in both the non-HV and HV groups with the minimum detectable change values ranging from 0.7° to 1.4°.

CONCLUSION

The measurement error of first metatarsal pronation using the axial view was clinically acceptable. The measurements were not influenced by the variability in foot position while obtaining the radiograph. The first metatarsal axial view could be used to quantify the first metatarsal coronal rotation.

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.

Timing of Intra-Articular Injection of Synovial Mesenchymal Stem Cells Affects Cartilage Restoration in a Partial Thickness Cartilage Defect Model in Rats

OBJECTIVE

We investigated the effect of administration of intra-articular mesenchymal stem cells (MSCs) on cartilage repair at different timings, and the distribution of MSCs in the knee.

DESIGN

A partial thickness cartilage defect (PTCD) was created on the medial femoral condyle in 14-week-old Sprague-Dawley rats. Intra-articular injection of 1 × 10⁶ MSCs was performed at 3 time points, namely at the time of surgery (0w group), at 1 week after surgery (1w group), and at 2 weeks after surgery (2w group). For the control, 50 μL phosphate-buffered saline was injected at the time of surgery. The femoral condyles were collected at 6 weeks after creation of PTCD and assessed histologically. To investigate the distribution of MSCs, fluorescent-labeled MSCs were injected into the knee joint.

RESULTS

In the control group, the cartilage lesion was distinguishable from surrounding cartilage. In the 0w group, hypocellularity and a slight decrease in safranin O stainability were observed around the injured area, but cartilage was restored to a nearly normal condition. In contrast, in the 1w and 2w groups, the cartilage surface was irregular and safranin O stainability in the injured and surrounding areas was poor. Histological score in the 0w group was significantly better than in the control, 1w, and 2w groups. At 1 day postinjection, fluorescent-labeled MSCs were mostly distributed in synovium. However, no migration into the PTCD was observed.

CONCLUSIONS

Early intra-articular injection of MSCs was effective in enhancing cartilage healing in a rat PTCD model. Injected MSCs were distributed in synovium, not in cartilage surrounding the PTCD.

Avulsion fracture of the distal fibula is associated with recurrent sprain after ankle sprain in children

PURPOSE

The purpose of this study was to clarify radiographic and clinical outcomes, as well as their association, of ankle sprain in children.

METHODS

Patients who sustained a first-time ankle sprain were prospectively surveyed. Patients underwent radiography of the ankle in the mortise, lateral, anterior talofibular ligament (ATFL), and calcaneofibular ligament views at the first clinic visit to assess avulsion fractures of the distal fibula. Patients with avulsion fractures underwent radiography after 8 weeks to assess bone union. The treatment method was not standardized and was determined by the patient, their parents, and the treating physician. Recurrent sprain and quality of life were evaluated by using the Self-Administered Foot Evaluation Questionnaire and reviewing the medical records of patients. The association between avulsion fracture and recurrent sprain was assessed using univariate and multivariate analyses.

RESULTS

A total of 143 patients with a median age of 9 (range 6-12) years were analyzed. Avulsion fractures were present in 89 (62%) patients. The sensitivity of the ATFL view for the diagnosis of avulsion fractures was 0.94, whereas that for the anteroposterior and lateral views was significantly lower at 0.46 (P < 0.001). Only 17% of fractures united at 8 weeks. Of 114 (follow-up rate, 80%) patients who were followed up for a median period of 24 months, recurrent sprain occurred in 41 (36%) patients. The incidence rate was significantly higher in patients with avulsion fractures than in patients without the fractures (44 vs. 23%, P = 0.027). In multivariate logistic regression analysis, avulsion fracture was independently associated with recurrent sprain (P = 0.027).

CONCLUSION

More than one-third of patients experienced recurrent sprain. The presence of avulsion fracture was associated with an increased risk of recurrent sprain. Patients with avulsion fracture and their parents should be informed about the risk of recurrent sprain and subsequent ankle instability, and careful follow-up is needed for these patients.

LEVEL OF EVIDENCE

III.

Single vs. repeated matrix metalloproteinase-13 knockdown with intra-articular short interfering RNA administration in a murine osteoarthritis model

Purpose: Our aims were 1) to estimate the duration of short interfering RNA (siRNA) effect on matrix metalloproteinase-13 (Mmp-13) levels by a single intra-articular injection using a mouse knee osteoarthritis (OA) model and 2) to test whether repeated injections results in any additional suppressive effect on cartilage degradation compared to a single injection. Materials and Methods: OA was induced in 9 weeks old male C57BL/6 mice by destabilization of medial meniscus (DMM). Chemically modified siRNA targeted for Mmp-13 was injected into the knee joint at 1 week post-DMM surgery. Control group of knees received that for non-targeted genes. Synovial tissue was collected to measure Mmp-13 expression levels by quantitative polymerase chain reaction (qPCR) at 2, 3, and 6 weeks after surgery in each group. To test the effect of multiple injections, we created four experiment groups according to the number of injections. Histological assessment of articular cartilage was performed at 8 weeks post-DMM surgery. Results: In the Mmp-13 siRNA-treated group, expression levels of Mmp-13 mRNA were decreased by 40% compared to the control group at 2 weeks after surgery (p = 0.04), before returning to baseline at 3 weeks after surgery. A significant improvement in the histological score was observed in all Mmp-13 siRNA-treated groups compared to the control group (p < 0.05). However, no significant differences were seen between the single and multiple injection group. Conclusions: Our results suggested that the duration of siRNA effect in the knee joint lasts for at least 1 week, and that no further benefit is achieved by multiple injections.

Efficacy of foot orthoses as nonoperative treatment for hallux valgus: A 2-year follow-up study

BACKGROUND

The purpose of this study was to clarify the 2-year clinical and radiological outcomes of nonoperative treatment using foot orthosis for hallux valgus patients.

METHODS

Patients who underwent nonoperative treatment using foot orthosis were surveyed prospectively. Foot orthoses were made by one certified orthotist using the standardized method. Pain and quality of life were evaluated using subjective and objective assessment measures at 3, 6, 12, 18, and 24 months. Furthermore, radiological outcomes, patient satisfaction, and adherence to treatment were surveyed.

RESULTS

A total of 53 patients (50 women and 3 men; median age, 63 years) were included for analysis. The pain visual analogue scale score significantly decreased over time, with the lowest score observed at 12 months. The treatment effect was maintained over 24 months (median score, 52, 21, and 27 points at baseline, 12 months, and 24 months, respectively; P < .001). The Japanese Society for Surgery of the Foot hallux scale, American Academy of Orthopaedic Surgeons Foot and Ankle Scale, and 36-Item Short-Form Health Survey bodily pain subscale also improved, although the treatment effects were maximal at 6 months and decreased thereafter. At 24 months, 43 (81%) patients continued to use the orthosis, with the median visual analogue scale score for patient satisfaction of 76 points. The hallux valgus angle and intermetatarsal angle did not change during the 24-month period.

CONCLUSION

Nonoperative treatment using foot orthoses decreased pain in patients with hallux valgus. The effect of treatment was maintained up to 2 years with a relatively high degree of patient satisfaction. However, treating physicians should inform patients to set realistic expectations and be aware that a limited degree of pain reduction is expected.

Identification of transcription factors responsible for dysregulated networks in human osteoarthritis cartilage by global gene expression analysis

OBJECTIVE

Osteoarthritis (OA) is the most prevalent joint disease. As disease-modifying therapies are not available, novel therapeutic targets need to be discovered and prioritized for their importance in mediating the abnormal phenotype of cells in OA-affected joints. Here, we generated a genome-wide molecular profile of OA to elucidate regulatory mechanisms of OA pathogenesis and to identify possible therapeutic targets using integrative analysis of mRNA-sequencing data obtained from human knee cartilage.

DESIGN

RNA-sequencing (RNA-seq) was performed on 18 normal and 20 OA human knee cartilage tissues. RNA-seq datasets were analysed to identify genes, pathways and regulatory networks that were dysregulated in OA.

RESULTS

RNA-seq data analysis revealed 1332 differentially expressed (DE) genes between OA and non-OA samples, including known and novel transcription factors (TFs). Pathway analysis identified 15 significantly perturbed pathways in OA with ECM-related, PI3K-Akt, HIF-1, FoxO and circadian rhythm pathways being the most significantly dysregulated. We selected DE TFs that are enriched for regulating DE genes in OA and prioritized these TFs by creating a cartilage-specific interaction subnetwork. This analysis revealed eight TFs, including JUN, Early growth response (EGR)1, JUND, FOSL2, MYC, KLF4, RELA, and FOS that both target large numbers of dysregulated genes in OA and are themselves suppressed in OA.

CONCLUSIONS

We identified a novel subnetwork of dysregulated TFs that represent new mediators of abnormal gene expression and promising therapeutic targets in OA.

Age-dependent differences in response to partial-thickness cartilage defects in a rat model as a measure to evaluate the efficacy of interventions for cartilage repair

The objectives of this study are (1) to examine age-dependent longitudinal differences in histological responses after creation of partial-thickness articular cartilage defects (PTCDs) in rats and to use this model (2) to objectively evaluate the effectiveness of interventions for cartilage repair. Linear PTCDs were created at a depth of 100 μm in the weight-bearing region of the medial femoral condyle in rats of different ages (3 weeks, 6 weeks, 10 weeks and 14 weeks). One day, one week, two weeks, four weeks and twelve weeks after PTCD generation, spontaneous healing was evaluated histologically and immunohistochemically. Effects of interventions comprising mesenchymal stem cells (MSCs) or platelet-rich plasma (PRP) or both on 14-week-old PTCD rats were evaluated and compared with natural courses in rats of other ages. Younger rats exhibited better cartilage repair. Cartilage in 3-week-old and 6-week-old rats exhibited nearly normal restoration after 4-12 weeks. Cartilage in 14-week-old rats deteriorated over time and early signs of cartilage degeneration were observed. With injection of MCSs alone or MSCs + PRP, 14-week-old PTCD rats showed almost the same reparative cartilage as 6-week-old rats. With injection of PRP, 14-week-old PTCD rats showed almost the same reparative cartilage as 10-week-old rats. This model will be of great use to objectively compare the effects of interventions for small cartilage lesions and may help to advance the development of disease-modifying osteoarthritis drugs.

Comparative Analysis of Gene Expression between Cartilage and Menisci in Early-Phase Osteoarthritis of the Knee-An Animal Model Study

Cartilage degeneration is believed to be the primary event in the development of osteoarthritis (OA). On the other hand, meniscal degeneration is observed with high prevalence, and some researchers have pointed out that pathological changes in menisci precede that of cartilage. The purpose of the present study is to investigate comprehensive gene expression pattern of cartilage and menisci in the initial phase of surgically induced OA and to compare them. Secondary OA was surgically induced in 10-week-old male Wistar rats by anterior cruciate ligament transection (ACLT). Articular cartilage and menisci were separately dissected from six ACLT- and six sham-operated rats. Each specimen was analyzed by microarray, histological, and immunohistochemical analysis 3 weeks after surgery. Of the 36,685 transcripts detectable by microarray, the number of upregulated transcripts in ACLT menisci was >2.5-fold compared with that in ACLT menisci in any given threshold. Cluster analysis using the Database for Annotation Visualization and Integrated Discovery (DAVID) showed genes related to OA, such as response to stimulus, angiogenesis, and apoptosis, which were predominantly found in menisci in ACLT rats. Representative proteases including Adamts2, 4, Mmp2, 12, 13, 14, 16, extracellular matrix genes including versican (Vcan), lumican (Lum), syndecan1 (Sdc1), and Prostaglandin endoperoxide synthase2 (Ptgs2) were up-regulated in menisci, but were not up-regulated in cartilage. Our results indicated that the molecular changes that occurred in menisci preceded those occurred in cartilage in the very early phase of surgically induced OA models.

A comparative study of flat surface design and medial pivot design in posterior cruciate-retaining total knee arthroplasty: a matched pair cohort study of two years

Background

Component design is one of the contributory factors affecting the postoperative flexion angle. The purpose of this study was to compare short-term outcomes of flat surface and medial pivot designs in posterior cruciate-retaining (CR) total knee arthroplasty (TKA).

Methods

A retrospective, case-control, and observational cohort study consisted of matched-pairs of the flat surface design (Hi-Tech Knee II) and the medial pivot design (FINE Knee) in CR-TKA with a two-year follow-up period.

Results

Hi-Tech Knee II and FINE knee groups each included 7 males and 38 females. Surgical time was significantly shorter in the FINE Knee group than in the Hi-Tech Knee II group (104.8 min versus 154.9 min, p = 0.001). Estimated total blood loss was significantly lower in the FINE Knee group than in the Hi-Tech Knee II group (654 ml versus 1158 ml, p = 0.001). The postoperative flexion angle was significantly better in the FINE Knee group than in the Hi-Tech Knee II group (119.3 degrees versus 112.5 degrees), and was positively correlated with the preoperative flexion angle. Postoperative Knee Society scores were significantly better in the FINE Knee group than in the Hi-Tech Knee II group (93.0 points versus 85.0 points, p = 0.001), especially for postoperative pain relief (46.0 points versus 39.0 points out of 50, p = 0.001). Complications were not observed in either group over a two-year follow-up period.

Conclusion

The short-term outcome of the medial pivot design used in CR-TKA was more favorable than the flat surface design, especially for surgical time, estimated total blood loss, postoperative flexion angle, and knee pain.

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2138-z) contains supplementary material, which is available to authorized users.

The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study

Objectives

To compare the effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament (ACL) reconstruction animal model.

Methods

Anterior cruciate ligament reconstruction using the plantaris tendon as graft material was performed on both knees of 24 rabbits (48 knees) to mimic ACL reconstruction by two different suspensory fixation devices for graft fixation. For the adjustable fixation device model (Socket group; group S), a 5 mm deep socket was created in the lateral femoral condyle (LFC) of the right knee. For the fixed-loop model (Tunnel group; group T), a femoral tunnel penetrating the LFC was created in the left knee. Animals were sacrificed at four and eight weeks after surgery for histological evaluation and biomechanical testing.

Results

Histologically, both groups showed a mixture of direct and indirect healing patterns at four weeks, whereas only indirect healing patterns were observed in both groups at eight weeks. No significant histological differences were seen between the two groups at four and eight weeks in the roof zone (four weeks, S: mean 4.8 sd 1.7, T: mean 4.5 sd 0.5, p = 0.14; eight weeks, S: mean 5.8 sd 0.8, T: mean 4.8 sd 1.8, p = 0.88, Mann-Whitney U test) or side zone (four weeks, S: mean 5.0 sd 1.2, T: mean 4.8 sd 0.4, p = 0.43; eight weeks, S: mean 5.3 sd 0.8,T: mean 5.5 sd 0.8, p = 0.61, Mann-Whitney U test) . Similarly, no significant difference was seen in the maximum failure load between group S and group T at four (15.6 sd 9.0N and 13.1 sd 5.6N) or eight weeks (12.6 sd 3.6N and 17.1 sd 6.4N, respectively).

Conclusion

Regardless of bone tunnel configuration, tendon-bone healing after ACL reconstruction primarily occurred through indirect healing. No significant histological or mechanical differences were observed between adjustable and fixed-loop femoral cortical suspension methods.

Cite this article: Y. Sato, R. Akagi, Y. Akatsu, Y. Matsuura, S. Takahashi, S. Yamaguchi, T. Enomoto, R. Nakagawa, H. Hoshi, T. Sasaki, S. Kimura, Y. Ogawa, A. Sadamasu, S. Ohtori, T. Sasho. The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study. Bone Joint Res 2018;7:327–335. DOI: 10.1302/2046-3758.75.BJR-2017-0238.R2.

Prevalence and associated factors of foot and ankle pain among nurses at a university hospital in Japan: A cross-sectional study

OBJECTIVES

The purposes of this study were to clarify 1) the prevalence of foot and ankle pain and 2) the factors associated with foot and ankle pain among nurses.

METHODS

Nurses working at a university hospital in Japan were recruited to participate in this cross-sectional, questionnaire-based study. The occurrence of foot and ankle pain in the previous month was assessed by using the Standardized Nordic Questionnaire and the Manchester Foot Pain and Disability Index. Subjects also answered questions on footwear-related factors, including using the visual analog scale for shoe comfort. In addition, information on personal factors and psychosocial factors was collected using the Job Content Questionnaire. The relationships between the presence of foot and ankle pain and the associated factors were examined using multiple logistic regression analysis.

RESULTS

Responses of 636 nurses (response rate, 67%) were included for analysis. The prevalence of foot and ankle pain was 23% and 51% when using the Standardized Nordic Questionnaire and the Manchester Foot Pain and Disability Index, respectively. The prevalence of pain that prevented the nurses from performing activities of daily living and work was 4% and 17%, respectively. A low level of shoe comfort, personal factors (age and body mass index), and psychosocial factors (low job control and high job strain) was independently associated with the presence of foot and ankle pain.

CONCLUSIONS

Foot and ankle pain occurred frequently in nurses. Shoe comfort, personal factors, and psychosocial factors were associated with foot and ankle pain.

Evaluating different closed loop graft preparation technique for tibial suspensory fixation in ACL reconstruction using TightRope™

In most anterior cruciate ligament (ACL) reconstructions, grafts are fixed to the femoral side first followed by the tibial side. Various techniques have been reported to achieve optimal tension on the grafts, but once the grafts are fixed it is difficult to adjust graft tension further. To enable post fixation tension control we have invented a new graft configuration using an adjustable loop-device (TightRope^TM, Arthrex, FL, USA) on the tibial side. In this paper, biomechanical properties of this configuration using soft tissue were examined in terms of graft diameter and various suture techniques (referred to as base suture) to make a closed circle to support TightRope^TM.

Two experiments were conducted under different conditions. In each experiment, cyclic load, followed by a pull-to-failure load, was applied to the grafts and elongation and failure mode were recorded. (1) To evaluate the effects of diameter, 5.0 or 6.0 mm grafts were prepared by a single locking loop stitch as the base suture (SLL5, SLL6). (2) To evaluate different base sutures, 5.0 mm tendons were used, and grafts were prepared using five kinds of base sutures (SLL, ZLL: zigzag locking loop, DZLL: double zigzag locking loop, DK: double Krackow, DK w/o TR: double Krackow without TightRopeTM). In the first experiment, tearing was observed in 2 of 6 cases in the SLL5 test group, whereas no tearing was observed with SLL6. In the second experiment, no tearing was observed with DZLL or DK. Elongation was smaller in these two groups compared to the other groups. Mechanical strength decreases with a smaller graft diameter. Biomechanical properties differed with different base sutures and, among them, the double-zigzag-suture stitch and double Krackow provided less elongation and higher ultimate load in this graft configuration.

Stress fracture of the second proximal phalanx of the foot in teenage athletes: Unrecognized location of stress fracture

Background

Adolescent athletes are a high-risk population for stress fractures. We report four cases of stress fractures of the second proximal phalanx, which had not been previously diagnosed as the location of the stress fracture of the foot, in teenage athletes.

Case report

All fractures were on the plantar side of the proximal phalangeal base, and the oblique images of the plain radiograph clearly depicted the fractures. Notably, three out of the four patients had histories of stress fracture of other locations. While three athletes with acute cases were able to make an early return to play with simple conservative management, the chronic case required surgical treatment for this rare injury.

Conclusion

Although a rare injury, it is important that clinicians be aware of this type of stress fracture, as a timely diagnosis can avoid the need for surgical treatment and allow an early return to play.

Association of Anxiety and Depression With Pain and Quality of Life in Patients With Chronic Foot and Ankle Diseases

BACKGROUND

The purposes of this study were to clarify the incidence of anxiety and depression among patients with chronic foot and ankle diseases and to examine the independent association of anxiety and depression with pain and quality of life.

METHODS

Patients who visited the foot and ankle clinic from April 2015 to November 2016 were recruited. Anxiety and depression in patients were assessed using the Hospital Anxiety and Depression Scale. Pain and quality of life were evaluated using the visual analog scale (VAS) and Self-Administered Foot Evaluation Questionnaire (SAFE-Q), respectively. Furthermore, patient characteristics, including age, sex, body mass index, pain in other body areas, social support, employment, and household income, were surveyed. A multiple regression analysis was performed to examine the independent association of anxiety and depression with pain and quality of life. A total of 250 patients were included in the analysis.

RESULTS

The prevalence of anxiety and depression was 30% and 27%, respectively. The VAS and all SAFE-Q subscale scores were significantly worse in patients with anxiety or depression than in patients without the same (median VAS 63 vs 49 for anxiety, P = .005; 68 vs 47 for depression, P < .001). Furthermore, the multiple regression analyses showed that the presence of anxiety ( P = .02) and depression ( P < .001) was independently associated with increased pain, and it led to low scores on all SAFE-Q subscales ( P < .001 for all subscales).

CONCLUSION

About 30% of patients with chronic foot and ankle disease had anxiety or depression. The presence of these psychological symptoms was independently associated with worse pain and impaired quality of life after controlling for patient characteristics. Clinicians need to recognize the possibility of concurrent anxiety and depression to provide a more holistic treatment for chronic foot and ankle disease.

LEVEL OF EVIDENCE

Level IV, case series.

Increased DNA Methylation and Reduced Expression of Transcription Factors in Human Osteoarthritis Cartilage

OBJECTIVE

To analyze the methylome of normal and osteoarthritic (OA) knee articular cartilage and to determine the role of DNA methylation in the regulation of gene expression in vitro.

METHODS

DNA was isolated from human normal (n = 11) and OA (n = 12) knee articular cartilage and analyzed using the Infinium HumanMethylation450 BeadChip array. To integrate methylation and transcription, RNA sequencing was performed on normal and OA cartilage and validated by quantitative polymerase chain reaction. Functional validation was performed in the human TC28 cell line and primary chondrocytes that were treated with the DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-aza-dC).

RESULTS

DNA methylation profiling revealed 929 differentially methylated sites between normal and OA cartilage, comprising a total of 500 individual genes. Among these, 45 transcription factors that harbored differentially methylated sites were identified. Integrative analysis and subsequent validation showed a subset of 6 transcription factors that were significantly hypermethylated and down-regulated in OA cartilage (ATOH8, MAFF, NCOR2, TBX4, ZBTB16, and ZHX2). Upon 5-aza-dC treatment, TC28 cells showed a significant increase in gene expression for all 6 transcription factors. In primary chondrocytes, ATOH8 and TBX4 were increased after 5-aza-dC treatment.

CONCLUSION

Our findings reveal that normal and OA knee articular cartilage have significantly different methylomes. The identification of a subset of epigenetically regulated transcription factors with reduced expression in OA may represent an important mechanism to explain changes in the chondrocyte transcriptome and function during OA pathogenesis.

Safety and Efficacy of Intra-articular Injection of Platelet-Rich Plasma in Patients With Ankle Osteoarthritis

BACKGROUND

An intra-articular injection of platelet-rich plasma (PRP) may be an effective treatment for osteoarthritis (OA). However, its efficacy in ankle OA has not been investigated yet. The purpose of this study was to assess the safety and efficacy of an intra-articular injection of PRP in patients with ankle OA during a 24-week period.

METHODS

Twenty ankles of 20 patients with varus-type ankle OA who received intra-articular injections of PRP were evaluated. PRP was extracted from whole blood by using the double-spin technique. Three injections of 2-mL PRP were administered to the ankle at an interval of 2 weeks under ultrasonographic guidance. Adverse events and efficacy were assessed at 4, 12, and 24 weeks after the last injection. Clinical outcomes were assessed by using the visual analog scale (VAS) for pain, the Japanese Society for Surgery of the Foot (JSSF) ankle/hindfoot scale, and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q).

RESULTS

No serious adverse effects were observed during the follow-up period. The VAS and JSSF scale scores significantly decreased from baseline to 4, 12, and 24 weeks after treatment ( P < .001). The mean score in the pain-related subscale of the SAFE-Q significantly improved from baseline to 12 weeks after treatment ( P = .04). Overall, the amount of pain reduction was maximal at 12 weeks after the last injection, and the effect was reduced at 24 weeks. The patients with late-stage OA had worse scores in all outcomes than those with early-stage OA.

CONCLUSION

Intra-articular injections of PRP resulted in no serious adverse effects and significantly reduced pain in the patients with ankle OA. PRP treatment can be safe and effective and may be an option in the treatment of ankle OA.

LEVEL OF EVIDENCE

Level IV, case series.

Dysregulated circadian rhythm pathway in human osteoarthritis: NR1D1 and BMAL1 suppression alters TGF-β signaling in chondrocytes

OBJECTIVES

Circadian rhythm (CR) was identified by RNA sequencing as the most dysregulated pathway in human osteoarthritis (OA) in articular cartilage. This study examined circadian rhythmicity in cultured chondrocytes and the role of the CR genes NR1D1 and BMAL1 in regulating chondrocyte functions.

METHODS

RNA was extracted from normal and OA-affected human knee cartilage (n = 14 each). Expression levels of NR1D1 and BMAL1 mRNA and protein were assessed by quantitative PCR and immunohistochemistry. Human chondrocytes were synchronized and harvested at regular intervals to examine circadian rhythmicity in RNA and protein expression. Chondrocytes were treated with small interfering RNA (siRNA) for NR1D1 or BMAL1, followed by RNA sequencing and analysis of the effects on the transforming growth factor beta (TGF-β) pathway.

RESULTS

NR1D1 and BMAL1 mRNA and protein levels were significantly reduced in OA compared to normal cartilage. In cultured human chondrocytes, a clear circadian rhythmicity was observed for NR1D1 and BMAL1. Increased BMAL1 expression was observed after knocking down NR1D1, and decreased NR1D1 levels were observed after knocking down BMAL1. Sequencing of RNA from chondrocytes treated with NR1D1 or BMAL1 siRNA identified 330 and 68 significantly different genes, respectively, and this predominantly affected the TGF-β signaling pathway.

CONCLUSIONS

The CR pathway is dysregulated in OA cartilage. Interference with circadian rhythmicity in cultured chondrocytes affects TGF-β signaling, which is a central pathway in cartilage homeostasis.

The recognition and incidence of peroneal tendon dislocation associated with a fracture of the talus

AIMS

The purposes of this study were to clarify first, the incidence of peroneal tendon dislocation in patients with a fracture of the talus and second the factors associated with peroneal tendon dislocation.

PATIENTS AND METHODS

We retrospectively examined 30 patients (30 ankles) with a mean age of 37.5 years, who had undergone internal fixation for a fracture of the talus. Independent examiners assessed for peroneal tendon dislocation using the pre-operative CT images. The medical records were also reviewed for the presence of peroneal tendon dislocation. The associations between the presence of dislocation with the patient characteristics or radiological findings, including age, mechanism of injury, severity of fracture, and fleck sign, were assessed using Fisher's exact tests.

RESULTS

The pre-operative CT images showed peroneal tendon dislocation in eight out of 30 patients. Dislocation was found later in one patient whose pre-operative CT image had not shown dislocation. The overall incidence of peroneal tendon dislocation was 30% (9/30). The presence of dislocation was associated with the presence of a fleck sign (p = 0.03).

CONCLUSIONS

Surprisingly, approximately one-third of the patients who underwent internal fixation for a fracture of the talus had peroneal tendon dislocation. This was associated with a fleck sign. Cite this article: Bone Joint J 2017;99-B:489-93.

The effect of systemic administration of G-CSF on a full-thickness cartilage defect in a rabbit model MSC proliferation as presumed mechanism: G-CSF for cartilage repair

Objectives

The aim of this study was to investigate the effect of granulocyte-colony stimulating factor (G-CSF) on mesenchymal stem cell (MSC) proliferation in vitro and to determine whether pre-microfracture systemic administration of G-CSF (a bone marrow stimulant) could improve the quality of repaired tissue of a full-thickness cartilage defect in a rabbit model.

Methods

MSCs from rabbits were cultured in a control medium and medium with G-CSF (low-dose: 4 μg, high-dose: 40 μg). At one, three, and five days after culturing, cells were counted. Differential potential of cultured cells were examined by stimulating them with a osteogenic, adipogenic and chondrogenic medium.

A total of 30 rabbits were divided into three groups. The low-dose group (n = 10) received 10 μg/kg of G-CSF daily, the high-dose group (n = 10) received 50 μg/kg daily by subcutaneous injection for three days prior to creating cartilage defects. The control group (n = 10) was administered saline for three days. At 48 hours after the first injection, a 5.2 mm diameter cylindrical osteochondral defect was created in the femoral trochlea. At four and 12 weeks post-operatively, repaired tissue was evaluated macroscopically and microscopically.

Results

The cell count in the low-dose G-CSF medium was significantly higher than that in the control medium. The differentiation potential of MSCs was preserved after culturing them with G-CSF.

Macroscopically, defects were filled and surfaces were smoother in the G-CSF groups than in the control group at four weeks. At 12 weeks, the quality of repaired cartilage improved further, and defects were almost completely filled in all groups. Microscopically, at four weeks, defects were partially filled with hyaline-like cartilage in the G-CSF groups. At 12 weeks, defects were repaired with hyaline-like cartilage in all groups.

Conclusions

G-CSF promoted proliferation of MSCs in vitro. The systemic administration of G-CSF promoted the repair of damaged cartilage possibly through increasing the number of MSCs in a rabbit model.

Cite this article: T. Sasaki, R. Akagi, Y. Akatsu, T. Fukawa, H. Hoshi, Y. Yamamoto, T. Enomoto, Y. Sato, R. Nakagawa, K. Takahashi, S. Yamaguchi, T. Sasho. The effect of systemic administration of G-CSF on a full-thickness cartilage defect in a rabbit model MSC proliferation as presumed mechanism: G-CSF for cartilage repair. Bone Joint Res 2017;6:123–131. DOI: 10.1302/2046-3758.63.BJR-2016-0083.

Quantitative US Elastography Can Be Used to Quantify Mechanical and Histologic Tendon Healing in a Rabbit Model of Achilles Tendon Transection

Purpose To determine the time-dependent change in strain ratios (SRs) at the healing site of an Achilles tendon rupture in a rabbit model of tendon transection and to assess the correlation between SRs and the mechanical and histologic properties of the healing tissue. Materials and Methods Experimental methods were approved by the institutional animal care and use committee. The Achilles tendons of 24 New Zealand white rabbits (48 limbs) were surgically transected. The SRs of Achilles tendons were calculated by using compression-based quantitative ultrasonographic elastography measurements obtained 2, 4, 8, and 12 weeks after transection. After in vivo elastography, the left Achilles tendon was harvested for mechanical testing of ultimate load, ultimate stress, elastic modulus, and linear stiffness, and the right tendons were harvested for tissue histologic analysis with the Bonar scale. Time-dependent changes in SRs, mechanical parameters, and Bonar scale scores were evaluated by using repeated-measures analysis of variance. The correlation between SRs and each measured variable was evaluated by using the Spearman rank correlation coefficient. Results Mean SRs and Bonar scale values decreased as a function of time after transection, whereas mechanical parameters increased (P < .001). SR correlated with ultimate stress (ρ = 0.68, P <.001,) elastic modulus (ρ = 0.74, P <.001), and the Bonar scale (ρ = 0.87, P <.001). Conclusion Quantitative elastography could be a useful method with which to evaluate mechanical and histologic properties of the healing tendon. ^© RSNA, 2017 Online supplemental material is available for this article.

Direct anterior approach for total hip arthroplasty with a novel mobile traction table -a prospective cohort study

Background

The purpose of this prospective cohort study was to clarify the safety and efficacy of total hip arthroplasty via the direct anterior approach in the supine position with a novel mobile traction table.

Methods

The first experience of consecutive surgeries by a single surgeon using the direct anterior approach with a traction table is described with a two-year follow-up period. Of 121 patients, 100 patients without previous hip surgeries, severe deformity, or cemented implants were divided into two groups comprising the first 50 patients and the second 50 patients.

Results

The implant survival rate was 99% at the two-year follow-up. Revision surgery was required for periprosthetic femoral fracture in one patient. The complication rate possibly related to the traction table was 5% (5 patients): three anterior dislocations, one periprosthetic femoral fracture, and one intraoperative perforation caused by femoral rasping. The complication rate tended to decrease in the second group compared to the first group (4% versus 6%). Mean surgical time (72.0 minutes versus 82.5 min, p = 0.027), rate of allogeneic blood transfusion (2% versus 24%, p = 0.001), and cup alignment in the safe zone (100% versus 88%, p = 0.027) were significantly improved in the second group compared to the first group.

Conclusion

The direct anterior approach with a novel mobile traction table showed a positive learning curve for surgical time, rate of allogeneic blood transfusion, and cup alignment in the safe zone.

Effect of inhibiting MMP13 and ADAMTS5 by intra-articular injection of small interfering RNA in a surgically induced osteoarthritis model of mice

Matrix metalloproteinase 13 (MMP13) and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) are thought to play critical roles in cartilage degradation at the early phase of osteoarthritis (OA). The aim of this study is to examine the effect of chemically modified Mmp13 or Adamts5 small interfering RNA (siRNA), alone or in combination, in a mouse OA model. OA pathology was surgically induced in 9-week-old male C57/BL6 mice (n = 64) via destabilization of the medial meniscus (DMM). We used chemically modified siRNA (Accell siRNAs®) for Mmp13 and Adamts5, as well as a non-targeting control and evaluated their combined and individual effects after injection in the DMM model. The control group (n = 16) was injected with non-targeting siRNA and the normal group (n = 16) did not undergo any surgical induction or intra-articular injection. Histological assessment of the articular cartilage was conducted at 4 and 8 weeks post-DMM surgery to evaluate OA progression. Significant improvement in the histological score was observed at 8 weeks after DMM in all three siRNA-treated groups compared to the control siRNA-injected group. The score of the combined group was significantly lower than that of the Adamts5 siRNA-only group. No significant differences were noted between the Mmp13 siRNA-only group and the combined group. Combined intra-articular injection of Mmp13 and Adamts5 siRNA resulted in almost the same inhibitory effects as Mmp13 siRNA alone on cartilage degradation at the early phase of OA.

Quality of Life in Patients With Untreated and Symptomatic Hallux Valgus

BACKGROUND

The purposes of this study were to compare the quality of life (QOL) of subjects who had untreated symptomatic hallux valgus with the QOL of the general population and to investigate factors associated with the QOL of the subjects.

METHODS

One hundred sixteen subjects with previously untreated and symptomatic hallux valgus were surveyed. QOL was assessed using the 36-item Short Form Health Survey (SF-36). Additionally, clinical evaluations (the visual analog scale for pain, Japanese Society for Surgery of the Foot Scale, lesser toe pain, and pain in other parts of the body) and radiographic evaluations (hallux valgus angle, intermetatarsal angle between the first and second metatarsals, and dislocation of the second metatarsophalangeal joint) were performed. Differences in the SF-36 between the subjects and the general population were tested using independent t tests. Correlations between the QOL measurements, clinical evaluations, and radiographic evaluations were assessed using Spearman rank correlation coefficient.

RESULTS

All SF-36 subscales and physical component summary scores for the subjects were significantly lower than those of the general population. Notably, the standardized physical function subscale (38.2 ± 15.8, P < .001) and physical component summary scores (38.9 ± 14.5, P < .001) were more than 10 points lower than those of the general population. Most QOL and clinical evaluation parameters were not correlated or were negligibly correlated with radiographic evaluations. Similarly, lesser toe pain or pain in other parts of the body was not correlated with QOL or clinical evaluations.

CONCLUSION

The QOL of untreated and symptomatic hallux valgus subjects was lower than that of the general population. All QOL and clinical evaluation parameters were not significantly or negligibly correlated with the severity of toe deformities. Surgical decision making should not be based on the severity of the deformity alone, but rather patient QOL should also be carefully assessed.

LEVEL OF EVIDENCE

Level III, comparative series.