Screening of Undiagnosed Increased Lateral Ankle Laxity Using Stress Ultrasonography.

Background: Some patients with lateral ankle sprain (LAS) will experience chronic lateral ankle instability (CLAI). However, not all of those with residual increased lateral ankle laxity (ILAL) become symptomatic. There is a lack of evidence regarding the prevalence of undiagnosed ILAL in the general population. Purpose: To evaluate the prevalence of undiagnosed ILAL with the use of stress ultrasonography (US) and to investigate the percentage of ankle sprain copers (ASCs) with ILAL. Study Design: Cross-sectional study; Level of evidence, 3. Methods: The anterior talofibular ligament (ATFL) lengths in college students without diagnosis of CLAI were measured consecutively in stress and nonstress positions. The ATFL ratio was calculated as an indicator of lateral ankle laxity according to a previously reported method. The manual anterior drawer test was also performed. The Cumberland Ankle Instability Tool (CAIT) and Ankle Instability Instrument (AII) were used to assess subjective impairments related to CLAI. The correlation between the ATFL ratio and CAIT score was evaluated. Results: A total of 207 ankles from 106 participants (mean age, 23.9 ± 2.2 years; male/female, 64/42) were included. Overall, 38 participants (35.8%; 50 ankles [24.2%]) were classified as having undiagnosed ILAL. Of the ankles with no history of LAS, 8% showed ILAL. Overall, 53 participants (50%) had a history of LAS and were all classified as ASCs. Of the 82 ankles from these ASCs, 40 (48.8%) were regarded as having undiagnosed ILAL. There was no correlation between the ATFL ratio and CAIT scores (r = -0.09, P = .414). Conclusion: The prevalence of undiagnosed ILAL by stress US screening was approximately one-third in young adults. In this study, 48.8% of the ankles from ASCs showed ILAL.

Time elapsed from definitive diagnosis to surgery for osteonecrosis of the femoral head: a nationwide observational study in Japan.

OBJECTIVES: This study documents the time elapsed from the diagnosis of osteonecrosis of the femoral head (ONFH) to surgery, exploring the factors that influence ONFH severity. DESIGN: Retrospective observational study of a nationwide database. SETTING: The Kaplan-Meier method with log-rank tests was applied to examine the period from definitive diagnosis of ONFH to surgery using any surgery as the end point. For bilateral cases, the date of the first surgery was the endpoint. PARTICIPANTS: This study included 2074 ONFH cases registered in 34 university hospitals and highly specialised hospitals of the multicentre sentinel monitoring system of the Japanese Investigation Committee between 1997 and 2018. MAIN OUTCOME MEASURE: The primary outcome was the time from diagnosis to surgery. The secondary outcome was the proportion of subjects remaining without surgery at 3, 6 and 9 months, and at 1, 2 and 5 years after diagnosis. RESULTS: The median time to surgery was 9 months (IQR 4-22 months) after diagnosis of ONFH. The time to surgery was significantly shorter in the alcohol alone group and the combined corticosteroid and alcohol group than in the corticosteroid alone group (p=0.018 and p<0.001, respectively), in early stage ONFH with no or mild joint destruction (stages II and III, p<0.001), and with joint preserving surgery (p<0.001). The proportion without surgery was 75.8% at 3 months, 59.6% at 6 months, 48.2% at 9 months, 40.5% at 1 year, 22.2% at 2 years and 8.3% at 5 years. CONCLUSION: ONFH has been considered to be an intractable disease that often requires surgical treatment, but the fact that surgery was performed in more than half of the patients within 9 months from diagnosis suggests severe disease with a significant clinical impact. TRIAL REGISTRATION NUMBER: Chiba University ID1049.

Differences in Retromalleolar Fibular Groove Morphology According to Level of Axial Computed Tomography Scans.

Background: Studies have evaluated types of retromalleolar groove using axial magnetic resonance imaging at the level of 10 mm above the tip of the lateral malleolus. However, no evidence is available to support that this level is appropriate for evaluating retromalleolar groove morphology. Purpose: To assess the influence of the level of axial computed tomography (CT) scans on the assessment of retromalleolar groove morphology. Study Design: Cross-sectional study; Level of evidence, 3. Methods: The study population included 122 patients (mean age, 27.9 ± 11.8 years; 69 males, 53 female) who underwent CT scans to evaluate foot or ankle pathologies between 2020 and 2023. The shape of the retromalleolar groove (concave, flat, convex, or irregular) at 3 levels of axial CT scans (8, 10, and 12 mm above the tip of the lateral malleolus) was assessed independently by 2 orthopaedic surgeons. The length from the tip of the lateral malleolus to the proximal tip of the fossa of the lateral malleolus was also measured on coronal CT scans. Results: The type of retromalleolar groove was significantly different according to the level of CT scans (8 vs 10 mm, P = .0001; 10 vs 12 mm, P = .0001; 8 vs 12 mm, P = .001). The type of retromalleolar groove was the same at all 3 levels in 31.1% of patients (38/122). The length from the tip of the lateral malleolus to the proximal tip of the fossa of the lateral malleolus was <10 mm in 17.2% of patients (21/122). Conclusion: The shape of the retromalleolar fibular groove was affected by the level at which the CT scan was obtained. Approximately 70% of the patients showed different types of retromalleolar grooves among the 3 CT scan levels.

HMGB2 Promotes De Novo Lipogenesis to Accelerate Hepatocyte Proliferation During Liver Regeneration.

Liver regeneration is a well-orchestrated compensatory process that is regulated by multiple factors. We recently reported the importance of the chromatin protein, a high-mobility group box 2 (HMGB2) in mouse liver regeneration. However, the molecular mechanism remains unclear. In this study, we aimed to study how HMGB2 regulates hepatocyte proliferation during liver regeneration. Seventy-percent partial hepatectomy (PHx) was performed in wild-type (WT) and HMGB2-knockout (KO) mice, and the liver tissues were used for microarray, immunohistochemistry, quantitative polymerase chain reaction (qPCR), and Western blotting analyses. In the WT mice, HMGB2-positive hepatocytes colocalized with cell proliferation markers. In the HMGB2-KO mice, hepatocyte proliferation was significantly decreased. Oil Red O staining revealed the transient accumulation of lipid droplets at 12-24 hr after PHx in the WT mouse livers. In contrast, decreased amount of lipid droplets were found in HMGB2-KO mouse livers, and it was preserved until 36 hr. The microarray, immunohistochemistry, and qPCR results demonstrated that the expression of lipid metabolism-related genes was significantly decreased in the HMGB2-KO mouse livers. The in vitro experiments demonstrated that a decrease in the amount of lipid droplets correlated with decreased cell proliferation activity in HMGB2-knockdown cells. HMGB2 promotes de novo lipogenesis to accelerate hepatocyte proliferation during liver regeneration.

Risk factors of failure results after double-bundle reconstruction with autogenous hamstring grafts for isolated posterior cruciate ligament rupture cases.

Posterior tibial translation (PTT) after double-bundle posterior cruciate ligament (PCL) reconstruction has sometimes occurred. Purpose of this study is to identify the risk factors for postoperative PTT after double-bundle PCL reconstruction with a hamstring autograft. Comparing the results of bilateral gravity sag view (GSV) at 12 months after surgery, over 5-mm PTT was defined as 'failure' in this study. Of 26 isolated PCL reconstruction cases, over 5-mm PTT was seen in 7 cases (group F: 9.57 ± 1.28 mm), and 19 cases had less than 5 mm (group G: 2.84 ± 1.29 mm). Age, sex, body mass index (BMI), preoperative GSV, posterior slope angle of the tibia, anterolateral bundle (ALB) and posteromedial bundle (PMB) graft diameters, and tibial tunnel diameter were evaluated. The two groups were compared with the 2 × 2 chi-squared test, the Mann Whitney U-test, and Spearman's rank correlation coefficient. Multivariate logistic regression analysis was also performed to determine the risk factor. Statistical significance was indicated as p < 0.01 for correlation with postoperative PTT, and as p < 0.05 for all other comparisons. Mean age (group G 31.8 ± 12.5 vs group F 34.9 ± 15.9 years), sex (male/female: 15/4 vs 3/4), BMI (25.6 ± 4.6 vs 24.9 ± 3.9 kg/m2), preoperative GSV (11.3 ± 2.2 vs 11.6 ± 2.9 mm), PMB diameter (5.37 ± 0.33 vs 5.36 ± 0.48 mm), and tibial tunnel diameter (9.32 ± 0.58 vs 9.29 ± 0.49 mm) showed no significant differences. ALB diameter was significantly greater in group G (7.0 ± 0.5 mm) than in group F (6.5 ± 0.29 mm; p = 0.022). There was also a significant difference in posterior tibial slope angle (group G 9.19 ± 1.94 vs group F 6.54 ± 1.45, p = 0.004). On Spearman rank correlation coefficient analysis, ALB diameter GSV (correlation coefficient: - 0.561, p = 0.003) and posterior tibial slope angle (correlation coefficient: - 0.533, p = 0.005) showed a significant correlation with postoperative PTT. Multivariate logistic regression analysis showed that ALB diameter (OR 19.028; 95% CI 1.082-334.6; p = 0.044) and posterior slope angle of tibia (OR 3.081; 95% CI 1.109-8.556; p = 0.031) were independently associated with postoperative PTT, respectively. In double-bundle PCL reconstruction with hamstring, smaller ALB graft diameter and lower (flatted) tibial slope angle were considered risk factors for postoperative PTT.

Association between restricted outings and geriatric locomotive function scale score in the general elderly population during the COVID-19 pandemic.

BACKGROUND: Restrictions in daily activities due to coronavirus infection countermeasures reduced opportunities for physical activity and social participation in people of all ages. This study investigated the associations of restricted outings on locomotive function during the COVID-19 pandemic using a cohort of middle-aged and elderly community-dwelling residents. METHODS: Registered citizens of 50-89 years old were targeted for this investigation. We established 8 groups based on age (50's, 60's, 70's, and 80's) and gender (male and female) after random sampling from the basic resident registry of Obuse town in 2014. All participants were surveyed by a 25-question geriatric locomotive function scale (GLFS-25) at the time of checkup before the COVID-19 pandemic. Then, in 2021 and 2022 after government restrictions on outings were lifted for COVID-19 pandemic, all participants were mailed questionnaires including the GLFS-25. A total of 296 (143 male and 153 female) participants who responded at least once were included. We evaluated the changes in opportunities to go out between pre- and post-pandemic time points and the impact on GLFS-25 scores. RESULTS: In total, 128 (43.2%) respondents had fewer opportunities to go out than the previous year. Pre- and post-pandemic GLFS-25 scores in the decreased outing (+) group were significantly worse than in the decreased outing (-) group (both p < 0.01). The final multivariate model revealed GLFS-25 score worsening beta coefficient of 0.27 for age (+10 years), 3.97 for male, 4.54 for decreased outings, and 4.46 for spinal canal stenosis. CONCLUSIONS: In this randomly sampled Japanese cohort based on a resident registry, restricted outings during the COVID-19 pandemic was a significant independent factor associated with lower locomotive function.

Age- and sex-related differences in upper-body joint and endpoint kinematics during a drinking task in healthy adults.

Background: The objective kinematic assessments of activities of daily living are desired. However, the limited knowledge regarding age- and sex-related differences prevents the adaptation of these measurements to clinical settings and in-home exercises. Therefore, this study aimed to determine the effects of age and sex on joint and endpoint kinematics during a common activity of daily living, specifically, drinking from a glass. Methods: In total, 32 healthy adults (18 males and 14 females) aged 22-77 years performed a drinking task comprising reaching for a glass, bringing it forward and sipping, returning it, and placing the hand back to the starting position, which was recorded using a three-dimensional motion-capturing system. A two-way analysis of variance was used to statistically compare joint angles at five different time points and endpoint kinematic variables in the four drinking phases between older and younger age groups and sexes. Results: Wrist radial deviation was greater in older adults than in younger participants at all five different time points (F = 5.16-7.34, p ≤ 0.03, η2 = 0.14-0.21). Moreover, lesser shoulder abduction and greater shoulder internal rotation and forearm pronation when moving and returning the hand to the starting position were observed in the female group than in the male group (F = 4.21-20.03, p ≤ 0.0497, η2 = 0.13-0.41). Trunk flexion was lower in the female group than in the male group at all time points (F = 4.25-7.13, p ≤ 0.0485, η2 = 0.12-0.19). Regarding endpoint kinematics, the performance time in the reaching phase was longer in older adults than in younger individuals (F = 4.96, p = 0.03, η2 = 0.14). Furthermore, a shorter time while returning the hand to the starting position was observed in the female group than in the male group (F = 9.55, p < 0.01, η2 = 0.22). Conclusions: The joint kinematics of drinking were partially characterized by an age effect, whereas endpoint kinematics were scattered in all drinking phases. Sex-related effects in most upper-body motions and postures may cause rapid motions in females. Therefore, clinicians could use this knowledge for precise assessments and to suggest feasible in-home exercises.

Effect of age on upper limb, neck, and trunk kinematics during activities of daily living.

Motion analysis during activities of daily living has been conducted in numerous studies. However, information is lacking regarding age-related differences that affect clinical assessment and treatment goals. This study aimed to examine the effect of age on kinematics during activities of daily living. Three-dimensional motions of the shoulder, elbow, neck, and trunk of 12 younger adults (age, 29.8 ± 5.4 years; 7 men and 5 women) and 10 older adults (age, 69.5 ± 4.9 years; 6 men and 4 women) were measured during the acts of reaching for a table, bringing a glass to the mouth for drinking, wiping the buttocks, tying shoelaces, washing hair, washing the axilla, reaching for a high shelf, and reaching for the floor. The ranges of motion and sequential joint angles were compared between age groups by using discrete analysis and statistical parametric mapping, respectively. The ranges of motion of all joint angles in older and younger adults were comparable in the drinking, washing hair, washing the axilla, and reaching for the floor tasks. Statistical parametric mapping indicated that older adults had significantly poorer neck extension than did younger adults during the drinking (67-92% cycle time) and tying shoelaces (64-95% cycle time) tasks. Kinematics were mostly maintained in healthy older adults during activities of daily living. However, reduced motions were confirmed later during some tasks. The results indicated that existing knowledge combined with the current findings, which take age into account, could be used in clinical settings to assess the kinematics of activities of daily living and set treatment goals.

Increasing baseline aortic valve peak flow velocity is associated with progression of aortic valve stenosis in osteoporosis patients-a possible link to low vitamin D status.

PURPOSE: The purpose of this study was to investigate the morphological characteristics of the aortic valve and identify factors associated with the progression of aortic valve stenosis (AS) in osteoporosis patients. METHODS: In this single-center prospective cohort study, we recruited 10 patients (mean age: 75 ± 7 years, 90% female) who were taking anti-resorptive medicines at the outpatient clinic of University of Miyazaki Hospital, Japan. Baseline assessments, including transthoracic echocardiogram, blood sampling, and dual energy X-ray absorptiometry, were performed. Follow-up assessments were conducted at 6, 12, 18, and 24 months. RESULTS: During the 2-year follow-up, three patients with aortic valve peak flow velocity (AV PFV) ≥2 m/s at baseline developed moderate AS, which is defined as AV PFV ≥3 m/s. However, seven patients with AV PFV <2 m/s did not exhibit any progression of AS. There were significant variations in terms of bone mineral density, T-score values, and biomarkers associated with bone turnover (i.e., bone alkaline phosphatase, tartrate-resistance acid phosphatase-5b) among the enrolled patients, but none of these factors were found to be associated with the progression of AS. All patients exhibited low vitamin D status, with a median level of 16.1 ng/mL (25th percentile, 9.7 ng/mL; 75th percentile, 23 ng/mL). The baseline levels of AV PFV values were negatively correlated with 25-hydroxyvitamin D levels, determined by univariate linear regression analysis (beta coefficient = -0.756, 95% confidence interval, -0.136 ̶ -0.023, p = 0.011). CONCLUSION: Our data suggest that low vitamin D status might be a potential risk factor for the progression of AS in osteoporosis patients undergoing treatment with anti-resorptive medicines. Elderly patients with osteoporosis patients exhibited a subset of aortic valve stenosis. Our data suggest that the baseline aortic valve peak flow velocity predicts the progression of aortic valve stenosis, and there might be an association between the progression and the co-existing low vitamin D status in these patients.

Diagnostic utility of anteroposterior measurements of the median nerve on sagittal ultrasonographic images and their correlation with clinical findings in carpal tunnel syndrome.

PURPOSE: To investigate the efficacy of sagittal ultrasonography of the median nerve in diagnosing carpal tunnel syndrome (CTS). METHODS: Seventy-six hands with idiopathic CTS and 80 hands of asymptomatic subjects were included. All patients with CTS underwent ultrasonographic examination, electrodiagnostic testing, and CTS-6 assessment. In the sagittal ultrasonographic examination, the maximum and minimum median nerve diameters (MNDs) were measured at the proximal and distal ends of the carpal tunnel, respectively. The median nerve stenosis rate (MNSR) was computed as (1 - minimum MND/maximum MND) × 100 (%). The cross-sectional area (CSA) of the median nerve at the level of the pisiform was measured. RESULTS: In the sagittal ultrasonographic examination, the mean maximum MNDs were 0.252 cm and 0.202 cm, mean minimum MNDs were 0.145 cm and 0.165 cm, and mean MNSRs were 41.83% and 17.35% in the CTS and control groups, respectively; the mean maximum MND and MNSR were considerably larger in the CTS group. The maximum MND and MNSR were correlated with the electrodiagnostic testing results and CTS-6 score. The MNSR with a cut-off value of 34.0% had a higher sensitivity and specificity than the CSA in diagnosing CTS. CONCLUSIONS: Sagittal ultrasonographic examination is useful in diagnosing CTS.

Is the Small Ossicle of Type 1 Accessory Navicular a Cause of Foot Pain?-A Case Report.

Background and objectives: An accessory navicular (AN) bone is often classified into types 1-3 according to the Veitch classification, and symptomatic type 1 patients usually receive non-surgical treatment. However, there are cases in which AN cannot be classified into one of these three types using this classification system, and the small ossicle of type 1 AN may not be the cause of foot pain. This report aimed to present a case of symptomatic type 1 AN that required surgical treatment without the excision of the small ossicle after long-term conservative treatment had failed. Case presentation: A 15-year-old girl who was diagnosed with symptomatic type 1 AN was referred to our department. Medial-side foot pain had prevented her from playing soccer well. She had been treated conservatively for type 1 AN for more than 12 months at several orthopedic clinics. Tenderness of the prominent navicular tubercle was identified, and computed tomography and magnetic resonance imaging findings suggested that the cause of her foot pain was derived from the prominent navicular tubercle not the small ossicle itself. Osteotomy of the prominent navicular tubercle with the advancement of the tibialis posterior tendon, without excision of the ossicle, was performed. At the 12-month follow-up examination, she was completely free from foot pain, and the patient-reported outcome measures were excellent. She now plays soccer at the pre-injury level. Conclusions: We report the case of a patient with symptomatic type 1 AN who underwent osteotomy of the prominent navicular tubercle with advancement of the tibialis posterior tendon, without excision of the ossicle, and who showed favorable short-term clinical outcomes. The evaluation of symptomatic patients with AN based on the Veitch classification alone may lead to inappropriate management. The small ossicle of type 1 AN was not the cause of foot pain in the present case.

Tmem161a regulates bone formation and bone strength through the P38 MAPK pathway.

Bone remodeling is an extraordinarily complex process involving a variety of factors, such as genetic, metabolic, and environmental components. Although genetic factors play a particularly important role, many have not been identified. In this study, we investigated the role of transmembrane 161a (Tmem161a) in bone structure and function using wild-type (WT) and Tmem161a-depleted (Tmem161aGT/GT) mice. Mice femurs were examined by histological, morphological, and bone strength analyses. Osteoblast differentiation and mineral deposition were examined in Tmem161a-overexpressed, -knockdown and -knockout MC3T3-e1 cells. In WT mice, Tmem161a was expressed in osteoblasts of femurs; however, it was depleted in Tmem161aGT/GT mice. Cortical bone mineral density, thickness, and bone strength were significantly increased in Tmem161aGT/GT mice femurs. In MC3T3-e1 cells, decreased expression of alkaline phosphatase (ALP) and Osterix were found in Tmem161a overexpression, and these findings were reversed in Tmem161a-knockdown or -knockout cells. Microarray and western blot analyses revealed upregulation of the P38 MAPK pathway in Tmem161a-knockout cells, which referred as stress-activated protein kinases. ALP and flow cytometry analyses revealed that Tmem161a-knockout cells were resistant to oxidative stress. In summary, Tmem161a is an important regulator of P38 MAPK signaling, and depletion of Tmem161a induces thicker and stronger bones in mice.

Development of a video camera-type kayak motion capture system to measure water kayaking.

Background: In kayaking, trunk motion is one of the important factors that prevent injury and improve performance. Kinematic studies in kayaking have been reported in laboratory settings using paddling simulators and ergometers. However, such studies do not reflect kayaking on water, the actual competitive environment. Therefore, we developed a video camera-type kayak motion capture system (KMCS) wherein action cameras were fixed to a kayak to capture images of markers attached to an athlete's body. This study aimed to compare the kinematic data between KMCS and an optical motion capture system (OMCS) in kayaking and to determine the accuracy of the KMCS analysis. Methods: In a competition, five elite junior female kayak athletes performed kayak paddling under the unloaded condition using a kayak. The kayak was secured using a tri-folding bench and a towel, and twenty strokes were recorded during maximal paddling. One stroke was defined as the period from right catch to left catch, and the first six strokes were used to evaluate the accuracy. Trunk angles (tilting, turning, and rotation) were examined with the simultaneous use of KMCS and OMCS, and the differences between these systems were evaluated. To ensure reliability, intraclass correlation coefficient (ICC; a two-way mixed model for absolute agreement) was calculated for each angle. Furthermore, Bland-Altman analysis was performed to understand the agreement between the two systems. Results: Root mean square errors (RMSEs) were 1.42° and 3.94° for turning and rotation, respectively, and mean absolute errors (MAEs) were 1.08° and 3.00° for turning and rotation, respectively. The RMSE and MAE for tilting were 2.43° and 1.76°, respectively, which indicated that the validity was comparable to that of other angles. However, the range of motion in tilting was lower than that in turning and rotation. Bland-Altman analysis showed good agreement in the total range of motion, with mean bias values of -0.84°, -0.07°, and -0.41° for tilting, turning, and rotation, respectively. The ICCs for tilting, turning, and rotation were 0.966, 0.985, and 0.973, respectively, and showed excellent reliability. Conclusions: The newly developed KMCS effectively measured the trunk motion with good accuracy in kayaking. In future studies, we intend to use KMCS to measure kayaking on water and collect data for performance improvement and injury prevention.

Shear stress in the medial meniscus posterior root during daily activities.

BACKGROUND: Medial meniscus posterior root (MMPR) tears have been reported to occur in middle-aged patients with minor trauma. However, the injury mechanism of MMPR tears remains unclear. The purpose of this study was to evaluate the shear stress in the MMPR during daily activities using a finite-element analysis. METHODS: Subject-specific finite-element models of the knee joint of a healthy middle-aged subject were developed from computed tomographic and magnetic resonance images. A three-dimensional motion capture system "VICON" was used to capture four daily activities: walking, jogging, descending stairs, and landing. The knee joint reaction force was estimated using the AnyBody modeling system. Based on these procedures, the shear stress in the MMPR was calculated during each motion. The shear stress in the lateral meniscus posterior root (LMPR) was also measured to compare the stress between the MMPR and LMPR. RESULTS: The shear stress in the MMPR increased as the knee flexion angle increased during each motion. Descending stairs caused more than two-fold greater stress in the MMPR than walking and a similar or greater amount of stress than jogging. The LMPR tended to receive more shear stress than the MMPR throughout each motion. CONCLUSIONS: The present study showed that descending stairs confers almost the same amount of shear stress to the MMPR as jogging. The results of the present study may suggest that descending motion of the knee is an important cause of MMPR tear, and the initiation of descending stairs should be delayed after MMPR repair.

Retrograde Autologous Talar Osteocancellous Bone Grafting for the Treatment of Osteochondral Lesions of the Talus: A Technical Note.

Osteochondral lesions of the talus (OLT) are common injuries in young athletes. Various kinds of surgical procedures are available for orthopaedic surgeons, but which surgical technique is the best remains controversial. Many surgical procedures require malleolar osteotomy to obtain appropriate surgical exposure to the OLT because of the anatomic characteristics of the ankle joint. However, malleolar osteotomy is invasive and has a potential risk of complications, such as tibial chondral damage and pseudoarthrosis. This article aims to introduce a novel surgical procedure for the treatment of OLTs: retrograde autologous talar osteocancellous bone grafting without the need for osteotomy and harvesting a graft from anywhere other than the talus. First, an arthroscopic evaluation is performed to verify the location, size, and cartilage quality of the OLT as well as concomitant lesions. After confirming the position of the guide pin using a guide device arthroscopically, a talar osteocancellous bone plug is harvested using a coring reamer. The OLT of the harvested talar bone plug is removed, and under arthroscopy, the talar osteocancellous bone plug is retrogradely inserted into the talar bone tunnel. To stabilize the implanted bone plug, one or two bioabsorbable pins are inserted from the lateral wall of the talus while applying counterforce to the articular surface of the bone plug. The present surgical technique can minimally invasively address the OLT without the need for malleolar osteotomy and harvesting a graft from the knee joint or iliac bone.

Ureter position and risk of ureteral injury during lateral lumbar interbody fusion.

BACKGROUND: Ureteral injury during lateral lumbar interbody fusion (LLIF) is uncommon. However, it is a serious complication that may require additional surgery should it occur. The objective of this study was to evaluate whether there was any change in the position of the left ureter between preoperative biphasic contrast-enhanced CT scanned in the supine position and intraoperative scanning in the right lateral decubitus position after stent placement, to assess the risk of ureteral injury in the actual surgical position. METHODS: The position of the left ureter scanned with the O-arm navigation system with the patient in the right lateral decubitus position and its position on preoperative biphasic contrast-enhanced CT images scanned with the patient in the supine position were investigated comparing their positions at the L2/3, L3/4, and L4/5 levels. RESULTS: The ureter was located along the interbody cage insertion trajectory in 25 of 44 disc levels (56.8%) in the supine position, but in only 4 (9.5%) in the lateral decubitus position. The proportion of patients in whom the left ureter was located lateral to the vertebral body (along the LLIF cage insertion trajectory) at each level was 80% in the supine position and 15.4% in the lateral decubitus position at the L2/3 level, 53.3% in the supine position and 6.7% in the lateral decubitus position at the L3/4 level, and 33.3% in the supine position and 6.7% in the lateral decubitus position at the L4/5 level. CONCLUSION: The proportion of patients in whom the left ureter was located on the lateral surface of the vertebral body when the patient was in the actual surgical position (lateral decubitus position) was 15.4% at the L2/3 level, 6.7% at the L3/4 level, and 6.7% at the L4/5 level, suggesting that caution is required during LLIF surgery.

Weight-shifting-based robot control system improves the weight-bearing rate and balance ability of the static standing position in hip osteoarthritis patients: a randomized controlled trial focusing on outcomes after total hip arthroplasty.

Background: After a total hip arthroplasty (THA), standing and walking balance are greatly affected in the early stages of recovery, so it is important to increase the weight-bearing amount (WBA) on the operated side. Sometimes, traditional treatments may not be enough to improve WBA and weight-bearing ratio (WBR) on the operated side in a satisfactory way. To solve this problem, we came up with a new weight-shifting-based robot control system called LOCOBOT. This system can control a spherical robot on a floor by changing the center of pressure (COP) on a force-sensing board in rehabilitation after THA. The goal of this study was to find out how rehabilitation with the LOCOBOT affects the WBR and balance in a static standing position in patients with unilateral hip osteoarthritis (OA) who had a primary uncemented THA. Methods: This randomized controlled trial included 20 patients diagnosed with Kellgren-Lawrence (K-L) grade 3 or 4 hip OA on the operative side and K-L grade 0 normal hip on the nonoperative side. We used the minimization method for allocation and randomly assigned patients to either the LOCOBOT group or the control group. As a result, 10 patient seach were randomly assigned to the LOCOBOT and control groups. Both groups received 40 min of rehabilitation treatment. Out of the 40 min, the LOCOBOT group underwent treatment for 10 min with LOCOBOT. The control group performed COP-controlled exercises on a flat floor instead of using LOCOBOT for 10 of the 40 min. All theoutcome measures were performed pre-THA and 11.9 ± 1.6 days after THA (12 days after THA). The primary outcome measure included WBR in the static standing position. Results: After12 days of THA, the LOCOBOT group exhibited significantly higher mean WBR and WBA (operated side) values than the control group. Furthermore, the LOCOBOT group exhibited significantly lower mean WBA (non-operated side) and outer diameter area (ODA) values than the control group. From pre-THA to 12 days after THA, the LOCOBOT group exhibited a significant improvement in mean WBR and WBA (operated side). Moreover, the mean WBA (non-operated side) and ODA significantly decreased. From pre-THA to 12 days after THA, the control group showed a significant increase in total trajectory length and ODA. Conclusions: The most important finding of this study was that patients were able to perform the LOCOBOT exercise as early as the second day after THA, and that WBR and ODA significantly improved by the 12th day after THA. This result demonstrated that the LOCOBOT effectively improves WBR in a short period of time after THA and is a valuable system for enhancing balance ability. This expedites the acquisition of independence in activities of daily living after THA and may contribute to optimizing the effectiveness of medical care.

Evaluation of Sit-to-Stand Movement in Older Adults with Locomotive Syndrome Using the Nintendo Wii Balance Board.

Standing up from a chair is a mechanically demanding daily motion, and its biomechanics represent motor performance. In older adults with locomotive syndrome (LS), sit-to-stand (STS) movement with adequate postural control is essential to prevent falls. This study evaluated the characteristics of dynamic balance during STS movement on older adults with LS. A total of 116 participants aged ≥65 years were divided into Non-LS, LS stage 1, and LS stage 2 groups using the LS risk test. The participants were instructed to stand on the Nintendo Wii Balance Board as quickly as possible, and the STS movement was quantified using the vertical ground reaction force (VGRF) and center of pressure (CoP). The STS score, which represented dynamic balance, was significantly different among the groups (p < 0.001). The rate of VGRF development was significantly lower in the LS stages 1 and 2 than in the Non-LS group (p < 0.001). On the other hand, the total distance of the CoP path did not differ among the groups (p = 0.211). These findings indicated a reduction of postural control in older adults with LS. The STS score emphasized the importance of balance training to prevent falls in older adults with LS.

Three-dimensional fine structures in deep fascia revealed by combined use of cryo-fixed histochemistry and low-vacuum scanning microscopy.

Recent physiological studies have shown that the deep fascia has received much attention concerning clinical medicine; however, histological examination of the deep fascia has not been well established. In this study, we aimed to clarify and visualize the structure of the deep fascia by taking advantage of cryofixation techniques and low-vacuum scanning electron microscopy. As a result, the ultrastructural observations revealed three-dimensional stratification of the deep fascia composed of three layers: the first superficial layer consisting of collagen fibers extending in various directions with blood vessels and peripheral nerves; the second intermediate layer formed by single straight and thick collagen fibers with flexibility; and the third deepest layer, consisting of relatively straight and thin collagen fibers. We explored the use of two hooks to hold a piece of deep fascia in place through the course of cryo-fixation. A comparative observation with or without the hook-holding procedure would indicate the morphological adaptation to physiological stretch and contraction of the deep fascia. The present morphological approach paves the way to visualize three-dimensional ultrastructures for future biomedical studies including clinical pathophysiology.

Risk factors associated with throwing injuries in young baseball players.

BACKGROUND: Few studies have retrospectively analyzed the relationship between joint range of motion (ROM) and muscle flexibility and shoulder and elbow throwing injuries in a large number of elementary school baseball players. The purpose of this study was to retrospectively identify the physical factors related to shoulder and elbow throwing injuries in younger baseball players. METHODS: A total of 2466 younger baseball players belonging to our Prefecture Rubber Baseball Federation who participated in medical check-ups from 2016 to 2019 were analyzed. Players completed a questionnaire and had a medical check-up that included a physical examination and ultrasonography. ROM (internal rotation [IR] angle and external rotation angle) of the shoulder and hip and the finger-to-floor distance and heel-to-buttock distance were measured. The straight leg raise was also performed. The results of two groups (normal group and injury group) were compared using the χ2 test, Mann-Whitney U test, and Student t test. Stepwise forward logistic regression models were developed to identify risk factors. RESULTS: On univariate analysis, nine of the 13 evaluated items showed significant decreases in ROM and muscle flexibility in the injury group. On multiple logistic regression analysis, grade, finger-to-floor distance, IR angle of the dominant side shoulder, and IR angle of the nondominant side hip were significantly associated with the occurrence of throwing injuries. Decreased total shoulder angle was observed not only on the dominant side but also on the nondominant side in the injury group. CONCLUSION: Decreased ROM and muscle flexibility were risk factors for baseball-related throwing injuries in elementary school baseball players. To prevent shoulder and elbow throwing injuries, players, coaches, medical staff, and parents need to be aware of these findings.