Publications by authors named "Kazuya Ikoma"

101 Publications

Hip fractures among the elderly in Kyoto, Japan: a 10-year study.

Arch Osteoporos 2021 02 12;16(1):30. Epub 2021 Feb 12.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

In Kyoto Prefecture, Japan, the number of hip fractures increased during 2013-2017 compared to 2008-2012. However, the estimated overall incidence rate increased only in femoral neck fractures in men aged ≥75 and women aged ≥85.

Purpose: The incidence rate of hip fractures in Japan has plateaued or decreased. We investigated the annual hip fracture occurrences in Kyoto Prefecture, Japan, from 2008 to 2017.

Methods: Patients aged 65 years and above who sustained hip fractures between 2008 and 2017 and were treated at one of the participating 11 hospitals were included. The total number of beds in these institutions was 3701, accounting for 21.5% of the 17,242 acute-care beds in Kyoto Prefecture. The change in incidence rate was estimated utilizing the population according to the national census conducted in 2010 and 2015.

Results: The total number of hip fractures was 10,060, with 47.5% femoral neck fractures and 52.5% trochanteric fractures. A decrease in number was seen only in trochanteric fractures in the group of 75- to 84-year-old women. The population-adjusted numbers of femoral neck fractures showed a significant increase in all age groups in men, whereas in women, there was an increase in femoral neck fractures in the ≥85 group and trochanteric fractures in the age group 65-74, and a decrease in trochanteric fractures in the age group 75-84. The estimated change in incidence rate showed an increase in femoral neck fractures in men aged ≥75 and women aged ≥85.

Conclusion: In Kyoto Prefecture, the number of hip fractures increased in the second half of the study period (2013-2017) compared to the first half (2008-2012). However, the incidence rate had not increased, except in femoral neck fractures in men aged ≥75 and women aged ≥85.
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http://dx.doi.org/10.1007/s11657-021-00888-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7880939PMC
February 2021

Foot orthosis treatment improves physical activity but not muscle quantity in patients with concurrent rheumatoid arthritis and sarcopenia.

Mod Rheumatol 2020 Nov 25:1-7. Epub 2020 Nov 25.

Department of Rehabilitation Medicine, Graduate School of Medical Science, University Hospital, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Objectives: Foot impairment in rheumatoid arthritis (RA) may exacerbate sarcopenia from physical inactivity because of foot pain while walking. The present study aimed to investigate the prevalence of sarcopenia in patients with RA-associated foot impairment, and whether treatment with a foot orthosis improved physical activity and muscle quantity.

Methods: Thirty-two patients with RA were diagnosed as sarcopenic or nonsarcopenic, and the prevalence of sarcopenia was determined. Eleven patients with sarcopenia were treated with a foot orthosis. The following parameters were compared between baseline and after 6 months of treatment: physical activity (walking, moderate-intensity activity, and vigorous-intensity activity), foot pain while walking, Health Assessment Questionnaire (HAQ) score, and body composition parameters, including muscle quantity.

Results: Sarcopenia was present in 25/32 patients (78.1%). The use of a foot orthosis improved walking activity ( = .02), foot pain while walking ( = .02), and HAQ score ( = .02). However, there were no significant changes in moderate- or vigorous-intensity activities or body composition parameters, including muscle quantity.

Conclusion: Patients with RA-associated foot impairment had a high rate of sarcopenia. Treatment with a foot orthosis increases light-intensity physical activity such as walking, but does not enhance moderate-to-vigorous-intensity activities or increase muscle quantity.
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http://dx.doi.org/10.1080/14397595.2020.1847714DOI Listing
November 2020

Can a relatively large spinal cord for the dural sac influence severity of paralysis in elderly patients with cervical spinal cord injury caused by minor trauma?

Medicine (Baltimore) 2020 Jun;99(26):e20929

Department of Rehabilitation Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, Japan.

Retrospective reviewThe degree of spinal cord compression and bony spinal canal stenosis are risk factors for the occurrence of spinal cord injury (SCI) without major fracture or dislocation, but they do not affect the severity of neurological symptoms. However, whether a relatively large spinal cord for the dural sac influences the severity of symptoms in SCI cases is unknown.The purpose of this study was to verify the influence of spinal cord size relative to dural sac on the severity of paralysis in elderly patients with cervical SCI caused by minor trauma.Subjects were 50 elderly patients with SCI caused by falls on flat ground. At 72 hours after injury, neurological assessment was performed using the Japanese Orthopaedic Association (JOA) scoring system. Bony canal anteroposterior diameters (APD) at mid C5 vertebral body were measured with computed tomography. We measured dural sac and spinal cord APD at the injured level and mid C5 with magnetic resonance imaging. Spinal cord compression ratio was calculated by dividing spinal cord at the injured level by spinal cord at mid C5. As the evaluation of spinal cord size relative to the dural sac, spinal cord/dural sac ratio was calculated at the injured level and mid C5. To clarify the factors influencing the severity of paralysis, the relationships between JOA score and those parameters were examined statistically.A significant negative correlation was observed between JOA score and spinal cord/dural sac ratio at mid C5. No clear relationship was observed between JOA score and bony canal APD or spinal cord compression ratio.In elderly patients with SCI caused by minor trauma, a relatively large spinal cord for the dural sac was shown to be a factor that influences the severity of paralysis. This result can be useful for the treatment and prevention of SCI in the elderly.
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http://dx.doi.org/10.1097/MD.0000000000020929DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7328921PMC
June 2020

Extensor hallucis longus tendon is a new distal landmark for coronal tibial component alignment in total knee arthroplasty: A study of magnetic resonance imaging.

J Orthop Surg (Hong Kong) 2020 Jan-Apr;28(1):2309499020912340

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Purpose: In total knee arthroplasty (TKA), various landmarks are generally used to ensure correct osteotomy. In this study, we examined whether the tibialis anterior tendon (TAT) or the extensor hallucis longus tendon (EHLT) could be used as a landmark of the center of the ankle joint in patients with knee osteoarthrosis (OA), using magnetic resonance imaging (MRI).

Methods: The subjects were 61 patients with OA in 79 knees (males: 8 with 9 knees and females: 53 with 70 knees). With the ankle joint secured in the intermediate position, MRI from the knee joint to the ankle joint was performed in the same foot position. We prepared individual lines connecting the center of the ankle joint with the TAT or EHLT to measure the angle difference (ΔA) from Akagi's line in the knee joint. We analyzed whether the ΔA might be affected by deformity of the knee joint or foot region, and tibial torsion.

Results: At the ankle joint level, the ΔA of EHLT was the smallest, with an average of 1.6 ± 3.4°. The ΔA for the femorotibial angle, hallux valgus angle, and varus-valgus angle showed no correlations with deformity of the knee joint and foot region, or tibial torsion.

Conclusions: MRI findings showed that EHLT would be useful as a landmark of the ankle joint center in extramedullary tibial osteotomy in TKA for medial knee OA. It was also clarified that the landmark would not be affected by severe deformity of the knee joint, deformity of the foot region, or external torsion of the tibia.
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http://dx.doi.org/10.1177/2309499020912340DOI Listing
December 2020

Reproducibility of radiographic methods for assessing longitudinal tarsal axes Part 2: Severe cavus or flatfoot study.

Foot (Edinb) 2020 Mar 20;42:101631. Epub 2019 Aug 20.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.

Introduction: Calcaneal pitch angle and Meary's angle are commonly used to assess longitudinal foot arches on lateral-view radiographs. The aim of this study was to examine and evaluate the radiographic longitudinal foot arch measurement methods with the best intraobserver and interobserver reliabilities for patients with (1) severe cavus deformity and (2) severe flatfoot deformity.

Methods: Standing radiographic images of 22feet with severe cavus foot deformity and 49feet with severe flatfoot deformity were obtained to measure the longitudinal axes of the talus, first metatarsal, calcaneus and plantar surface, which were defined using six, five, four and three different methods, respectively, selected from previous reports. Intraobserver and interobserver correlation coefficients were calculated.

Results: The results are generally consistent with those of Part 1. The best intraobserver and interobserver correlation coefficients for the tarsal axes were obtained using methods involving a line bisecting the angle formed by the lines tangential to the superior and inferior margins of the talus, a line connecting the centre of the first metatarsal head and the midpoint of the visualized base of the first metatarsal, and a line drawn tangential to the inferior surface of the calcaneus. For the plantar axis, a method that used the horizontal plane (as a reference axis) was regarded as the best approach.

Conclusions: The aforementioned methods were considered to be optimal for the radiographic assessment of longitudinal foot arches in patients with severe cavus or flatfoot deformity. This study may contribute to the more accurate assessment of any foot deformity.
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http://dx.doi.org/10.1016/j.foot.2019.08.002DOI Listing
March 2020

A retrospective study of antibacterial iodine-coated implants for postoperative infection.

Medicine (Baltimore) 2019 Nov;98(45):e17932

Department of Orthopedics, Graduate School of Medical Science, Kyoto prefectural University of Medicine, 465 Kajiicho Kyoto.

Postoperative infection is one of the most serious complications in orthopedic surgery. We have developed and use iodine-coated implants to prevent and treat postoperative infection in compromised hosts. This study evaluated outcomes using iodine-coated implants for postoperative infections.We treated 72 postoperative infected patients using iodine-coated implants. Of these, 38 were males and 34 were females, with a mean age of 59.3 years. The mean follow-up period was 5.6 years. The patients included 23 with an infection following total knee arthroplasty, 20 following total hip arthroplasty, 11 following osteosynthesis, 11 following spine surgery, 6 following tumor excision, and 1 following osteotomy. Of these, 37 underwent single-stage surgery and 35 underwent staged revision surgery. We performed staged surgery in any case with active infection. The survival of iodine-coated implants was determined using Kaplan-Meier analysis. White blood cell (WBC) and C-reactive protein (CRP) levels were measured pre- and postoperatively. To evaluate the systemic effects of iodine, serum thyroid hormone levels were examined.Five patients underwent re-revision surgery. In 3 patients, periprosthetic infection recurred at an average of 18 months after surgery. The reinfection rate was 4.2%. These patients recovered following reimplantation of iodine-coated prostheses. No patients required amputation. The survival rate of iodine-coated implants was 91%. There were no signs of infection at the latest follow-up. The median WBC level was nearly in the normal range, and CRP levels returned to normal within 4 weeks after surgery. No abnormalities of thyroid gland function were detected.Iodine-coated titanium implants can be very effective in the treatment of postoperative infections. An iodine coating can be safely applied to infected regions.
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http://dx.doi.org/10.1097/MD.0000000000017932DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6855576PMC
November 2019

Treadmill Running in Established Phase Arthritis Inhibits Joint Destruction in Rat Rheumatoid Arthritis Models.

Int J Mol Sci 2019 Oct 15;20(20). Epub 2019 Oct 15.

Department of Rehabilitation Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.

Exercise therapy inhibits joint destruction by suppressing pro-inflammatory cytokines. The efficacy of pharmacotherapy for rheumatoid arthritis differs depending on the phase of the disease, but that of exercise therapy for each phase is unknown. We assessed the differences in the efficacy of treadmill running on rheumatoid arthritis at various phases, using rat rheumatoid arthritis models. Rats with collagen-induced arthritis were used as rheumatoid arthritis models, and the phase after immunization was divided as pre-arthritis and established phases. Histologically, the groups with forced treadmill running in the established phase had significantly inhibited joint destruction compared with the other groups. The group with forced treadmill running in only the established phase had significantly better bone morphometry and reduced expression of connexin 43 and tumor necrosis factor α in the synovial membranes compared with the no treadmill group. Furthermore, few cells were positive for cathepsin K immunostaining in the groups with forced treadmill running in the established phase. Our results suggest that the efficacy of exercise therapy may differ depending on rheumatoid arthritis disease activity. Active exercise during phases of decreased disease activity may effectively inhibit arthritis and joint destruction.
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http://dx.doi.org/10.3390/ijms20205100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6834114PMC
October 2019

Effectiveness of medial-wedge insoles for children with intoeing gait who fall easily.

Turk J Phys Med Rehabil 2019 Mar 14;65(1):9-15. Epub 2019 Feb 14.

Hisashi Mouri, Wook-Cheol Kim, Yuji Arai, Takashi Yoshida, Yoshinobu Oka, Kazuya Ikoma, Hiroyoshi Fujiwara, Toshikazu Kubo.

Objectives: This study aims to investigate the effectiveness of orthosis therapy using a medial-wedge insole (MWI) with a height of 5 mm and an arch support for children with intoeing gait who are prone to falling.

Patients And Methods: Between January 1997 and July 2014, a total of 51 children (24 males, 27 females; mean age 5.0 years; range, 3 to 8 years) who were treated for an intoeing gait symptom of easily falling using the MWI (toe-in gait group) were included. The effectiveness of the MWI was evaluated based on the scores reported by children and their parents on a scale. Physical findings of the study group were also compared with a control group consisting of seven healthy children (4 males, 3 females; mean age 5.2 years; range, 3 to 6.2 years). Foot stability with and without MWI were assessed.

Results: The MWI was found to be effective in 80.8% of the toe-in gait group. Bilateral sum of the internal rotation angle of the hip (IRAB) was significantly higher (136±17°) (p=0.007) and bilateral sum of thigh foot angle (TFAB) significantly lower (-27±21°) (p<0.001) before using MWI in the toe-in gait group, compared to the control group. The maximum range of motion of the foot in six children in the toe-in gait group significantly decreased from 14.1±5.0° without MWI to 8.2±3.0° with MWI (p=0.002) in the gait analysis.

Conclusion: These study results suggest that MWI is effective in reducing the risk of falling in children with intoeing gait, mainly due to the internal torsion of the tibia or femur. In addition, it appears to be effective in improving the maximum range of motion of the foot.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6648186PMC
March 2019

REV-ERBα and REV-ERBβ function as key factors regulating Mammalian Circadian Output.

Sci Rep 2019 07 15;9(1):10171. Epub 2019 Jul 15.

Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan.

The circadian clock regulates behavioural and physiological processes in a 24-h cycle. The nuclear receptors REV-ERBα and REV-ERBβ are involved in the cell-autonomous circadian transcriptional/translational feedback loops as transcriptional repressors. A number of studies have also demonstrated a pivotal role of REV-ERBs in regulation of metabolic, neuronal, and inflammatory functions including bile acid metabolism, lipid metabolism, and production of inflammatory cytokines. Given the multifunctional role of REV-ERBs, it is important to elucidate the mechanism through which REV-ERBs exert their functions. To this end, we established a Rev-erbα/Rev-erbβ double-knockout mouse embryonic stem (ES) cell model and analyzed the circadian clock and clock-controlled output gene expressions. A comprehensive mRNA-seq analysis revealed that the double knockout of both Rev-erbα and Rev-erbβ does not abrogate expression rhythms of E-box-regulated core clock genes but drastically changes a diverse set of other rhythmically-expressed output genes. Of note, REV-ERBα/β deficiency does not compromise circadian expression rhythms of PER2, while REV-ERB target genes, Bmal1 and Npas2, are significantly upregulated. This study highlight the relevance of REV-ERBs as pivotal output mediators of the mammalian circadian clock.
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http://dx.doi.org/10.1038/s41598-019-46656-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6629614PMC
July 2019

Status of growth plates can be monitored by MRI.

J Magn Reson Imaging 2020 01 1;51(1):133-143. Epub 2019 May 1.

Department of Orthopedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Background: Growth plate injuries and disorders cause premature closure, resulting in shortened or deformed limbs. Quantitative assessment by MRI might monitor the status of the growth plate and may assist in the prediction of these deformations.

Purpose: To investigate whether the status of the growth plate can be monitored by quantitative evaluation using MRI of the noninjured region of the growth plate in a physeal injury model.

Study Type: Prospective, longitudinal.

Animal Model: A 3.0-mm drill was used to create an injury to the central region of the right proximal tibial growth plate in 5-week-old male Japanese white rabbits (N = 18). The left tibia served as the control.

Field Strength/sequence: 7.04T, T -weighted imaging, diffusion-weighted imaging.

Assessment: Eight of 18 rabbits underwent MRI, proton density-weighted imaging, and T -weighted and diffusion-weighted imaging. T and apparent diffusion coefficient (ADC) maps were generated for each image. The growth plate height and the T and ADC values of the noninjured region were measured. Two rabbits were sacrificed at 2, 4, 6, 8, and 10 weeks postinjury. Proximal tibial bones were evaluated using microcomputed tomography, histological, and immunohistological methods.

Statistical Tests: Data were compared using repeated-measures analysis of variance followed by Tukey post-hoc multiple comparison.

Results: Growth plate height decreased at 10 weeks postinjury (P = 0.018) on the injured side. T values were greater at 2 weeks postinjury (P = 0.0478) and decreased at 8 and 10 weeks (P = 0.0226, P = 0.0470, respectively) on the injured side. ADC values increased at 6 weeks on the lateral side (P = 0.0304) and decreased at 8 weeks and 10 weeks postinjury (P < 0.01) on the medial and injured sides, respectively.

Data Conclusion: Quantitative MRI can help monitor the status of the growth plate and capture its changes early.

Level Of Evidence: 1 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;51:133-143.
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http://dx.doi.org/10.1002/jmri.26771DOI Listing
January 2020

The influence of hallux valgus and flatfoot deformity on metatarsus primus elevatus: A radiographic study.

J Orthop Sci 2020 Mar 19;25(2):291-296. Epub 2019 Apr 19.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.

Background: Metatarsus primus elevatus (MPE), a dorsal elevation of the first metatarsal in relation to the lesser metatarsals on lateral-view radiographs, is an indicator of hallux rigidus. The angle between the articular surfaces of the base of the first metatarsal and the anterior part of the medial cuneiform (MCA) reflects the sagittal instability of the first tarsometatarsal (TMT) joint. MPE may also indicate instability of the first metatarsal. The purpose of this study was to identify the influence of hallux valgus (HV) and flatfoot (FF) deformities on measurements obtained from first metatarsal-related radiographic images.

Methods: Standing radiographic images of 134 feet were investigated. In dorsoplantar-view radiographs, HV and intermetatarsal angles were evaluated. The position of the medial sesamoid was classified with a grading system (Hardy score). In lateral-view radiographs, MPE, MCA, and Meary's angle were measured. The subjects were divided into 4 groups: the normal group (G1), HV(-)FF(-); the HV group (G2), HV(+)FF(-); the FF group (G3), HV(-)FF(+); and the dual group (G4), HV(+)FF(+). The radiographic parameters were compared among the groups.

Results: MPE in the HV patients (G2 and G4) was less than that in the non-HV participants (G1 and G3). MPE in G4 was less than that in G3. The odds ratios of the Hardy score were higher in G2, G3 and G4 than in G1. The ratios were higher in the FF patients (G3 and G4) than in the non-FF participants (G1 and G2) and were higher in G4 than in G2.

Conclusions: FF affects sesamoid dislocation, and the combination of HV and FF further increases sesamoid dislocation. Combined with M1C1A and the Hardy score, MPE may be a useful indicator of three-dimensional instability of the first TMT joint. First TMT joint-related operations may be considered for severe HV treatment in G4 patients.
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http://dx.doi.org/10.1016/j.jos.2019.03.020DOI Listing
March 2020

Reproducibility of radiographic methods for assessing longitudinal tarsal axes: Part 1: Consecutive case study.

Foot (Edinb) 2019 Sep 14;40:1-7. Epub 2019 Mar 14.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.

Introduction: Calcaneal pitch angle and Meary's angle are commonly used to assess longitudinal foot arches on lateral-view radiographs. However, the methods used to obtain the talar, first metatarsal, calcaneal, and plantar axes differ across multiple reports, and no study has evaluated the reproducibility of these approaches. The aim of this study was to determine the most reproducible methods for radiographically evaluating longitudinal axes.

Methods: Standing radiographic images of 40 feet from 21 consecutive outpatients were obtained to measure longitudinal axes of the talus, first metatarsal, calcaneus and plantar surface, which were defined using six, five, four and three different methods, respectively, selected from previous reports. Intraobserver and interobserver correlation coefficients were calculated.

Results: The best intraobserver and interobserver correlation coefficients for the talar, first metatarsal, and calcaneal axes were obtained using methods involving a line bisecting the angle formed by the lines tangential to the superior and inferior margins of the talus, a line connecting the centre of the first metatarsal head and the midpoint of the visualized base of the first metatarsal, and a line drawn tangential to the inferior surface of the calcaneus, respectively. For the plantar axis, a method that used the horizontal plane (as a reference axis) was regarded as the best approach, although intraobserver and interobserver correlation coefficients could not be calculated because all values were zero.

Conclusions: The aforementioned methods were considered to be optimal for the radiographic assessment of longitudinal foot arches. This study could contribute to more accurate assessments of foot deformities.
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http://dx.doi.org/10.1016/j.foot.2019.03.003DOI Listing
September 2019

Transiently proliferating perivascular microglia harbor M1 type and precede cerebrovascular changes in a chronic hypertension model.

J Neuroinflammation 2019 Apr 10;16(1):79. Epub 2019 Apr 10.

Department of Neurology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho Kamigyo-ku, Kyoto, 602-8566, Japan.

Background: Microglia play crucial roles in the maintenance of brain homeostasis. Activated microglia show a biphasic influence, promoting beneficial repair and causing harmful damage via M2 and M1 microglia, respectively. It is well-known that microglia are initially activated to the M2 state and subsequently switch to the M1 state, called M2-to-M1 class switching in acute ischemic models. However, the activation process of microglia in chronic and sporadic hypertension remains poorly understood. We aimed to clarify the process using a chronic hypertension model, the deoxycorticosterone acetate (DOCA)-salt-treated Wistar rats.

Methods: After unilateral nephrectomy, the rats were randomly divided into DOCA-salt, placebo, and control groups. DOCA-salt rats received a weekly subcutaneous injection of DOCA (40 mg/kg) and were continuously provided with 1% NaCl in drinking water. Placebo rats received a weekly subcutaneous injection of vehicle and were provided with tap water. Control rats received no administration of DOCA or NaCl. To investigate the temporal expression profiles of M1- and M2-specific markers for microglia, the animals were subjected to the immunohistochemical and biochemical studies after 2, 3, or 4 weeks DOCA-salt treatment.

Results: Hypertension occurred after 2 weeks of DOCA and salt administration, when round-shaped microglia with slightly shortened processes were observed juxtaposed to the vessels, although the histopathological findings were normal. After 3 weeks of DOCA and salt administration, M1-state perivascular and parenchyma microglia significantly increased, when local histopathological findings began to be observed but cerebrovascular destruction did not occur. On the other hand, M2-state microglia were never observed around the vessels at this period. Interestingly, prior to M1 activation, about 55% of perivascular microglia transiently expressed Ki-67, one of the cell proliferation markers.

Conclusions: We concluded that the resting perivascular microglia directly switched to the pro-inflammatory M1 state via a transient proliferative state in DOCA-salt rats. Our results suggest that the activation machinery of microglia in chronic hypertension differs from acute ischemic models. Proliferative microglia are possible initial key players in the development of hypertension-induced cerebral vessel damage. Fine-tuning of microglia proliferation and activation could constitute an innovative therapeutic strategy to prevent its development.
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http://dx.doi.org/10.1186/s12974-019-1467-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6456949PMC
April 2019

Early stage and small medial osteochondral lesions of the talus in the presence of chronic lateral ankle instability: A retrospective study.

J Orthop Sci 2020 Jan 21;25(1):178-182. Epub 2019 Feb 21.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Japan.

Background: In chronic lateral ankle instability (CLAI), the instability of the ankle joint results in repeated microtrauma to the articular cartilage. How the lesion condition or stage is affected by the presence of lateral instability in medial osteochondral lesions of the talus (OLT) is unclear. We aimed to examine whether CLAI is associated with the size and staging of medial OLT on radiographs, magnetic resonance (MR) images, and arthroscopy.

Methods: Forty-five patients with medial OLTs in 45 ankles were reviewed. Radiographs were assessed for damage and lesion classification. The tibio-talar tilting angle (TTA) was measured. The patients were divided into two groups: the CLAI group and the stable group. The lesion classification on radiographs, MR images, and arthroscopy, and size on MR images were statistically compared.

Results: The CLAI group had a mean TTA of 8.15 ± 3.41°, whereas the stable group had a mean TTA of 2.24 ± 1.64°. The CLAI group had a lower clinical score than the stable group at the initial visit to our clinic. The CLAI group presented with lesions of significantly shorter longitudinal and transverse diameters. Stages of medial OLT on radiographs, MR images, and arthroscopic evaluation were earlier in the CLAI group than those in the stable group.

Conclusions: Patients with CLAI presented in the early stages of OLT and had significantly smaller lesions than those without CLAI. The patients without CLAI may be selected for surgery at an early phase.
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http://dx.doi.org/10.1016/j.jos.2019.02.003DOI Listing
January 2020

Heme oxygenase-1 prevents glucocorticoid and hypoxia-induced apoptosis and necrosis of osteocyte-like cells.

Med Mol Morphol 2019 Sep 31;52(3):173-180. Epub 2019 Jan 31.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Glucocorticoids and hypoxia is considered to promote osteocyte apoptosis and necrosis, which are observed in glucocorticoid-associated osteonecrosis and osteoporosis. Heme oxygenase-1 (HO-1) induced by hemin is reported to have cytoprotective effects in ischemic diseases. The objective of this study was to evaluate the effect of HO-1 on osteocyte death caused by glucocorticoids and hypoxia. We confirmed that hemin induced HO-1 expression in MLO-Y4 mouse osteocytes. MLO-Y4 was cultured with dexamethasone (Dex) under hypoxia (DH group). Furthermore, these cells were cultured with hemin (DH-h group) or hemin and zinc protoporphyrin IX (an HO-1 inhibitor) (DH-h-PP group). The rates of apoptosis and necrosis of these groups were analyzed by flow cytometry and compared with cells cultured under normal condition. Both apoptosis and necrosis increased in the DH group. Hemin administration significantly reduced cell death caused by glucocorticoids and hypoxia in the DH-h group, and its effect was attenuated by the HO-1 inhibitor in DH-h-PP group. Capase-3 activity significantly decreased in the DH-h group. This implied that the cell death inhibition effect due to hemin is mediated by HO-1 and caspase-3. HO-1 induction may be useful in the treatment of glucocorticoid-associated osteonecrosis and osteoporosis.
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http://dx.doi.org/10.1007/s00795-018-00215-0DOI Listing
September 2019

Large deformity correction in medial open-wedge high tibial osteotomy may cause degeneration of patellofemoral cartilage: A retrospective study.

Medicine (Baltimore) 2019 Feb;98(5):e14299

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

To evaluate retrospectively any association between the degree of deformity correction by medial open-wedge high tibial osteotomy (HTO) and patellofemoral joint degeneration. We hypothesized that development of patellofemoral joint degeneration depended on the degree of intraoperative deformity correction.Fifty-seven patients who underwent medial open-wedge HTO for treatment of osteoarthritis in one knee were included in this study. Knees were classified into degeneration (D) and non-degeneration (ND) groups according to worsening of the patellar and/or femoral trochlear cartilage at the time of hardware removal (D group, 27 knees) and no degeneration or improvement (ND group, 30 knees). We compared pre- to post-surgery change in hip-knee-ankle angle (HKA) and medial-proximal-tibial angle (MPTA), open-wedge HTO correction angle, and arthroscopic findings between groups.Mean age, height, weight, and body mass index were 54.1 ± 9.9 years, 160.4 ± 8.7 cm, 66.4 ± 12.1 kg, and 25.7 ± 3.3 kg/m, respectively. Change in both HKA and MPTA differed significantly between groups. The MPTA cut-off values to predict patellofemoral degeneration were determined to be 10°, associated with an AUC of 0.75 (95% confidence interval [CI] 0.62-0.87).This study evaluated retrospectively the effect of the correction angle during medial open-wedge HTO on patellofemoral joint degeneration. If deformity correction exceeds an MPTA of 10° during open-wedge HTO, degeneration of patellofemoral joint needs to be considered.Level of evidence: Level IV.
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http://dx.doi.org/10.1097/MD.0000000000014299DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6380813PMC
February 2019

Leg Muscle Strength After Lateral Interbody Fusion Surgery Recovers Over Time After Temporary Muscle Weakness.

Clin Spine Surg 2019 04;32(3):E160-E165

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine.

Study Design: Case-control study.

Objective: The objective of this study was to reveal the changes of leg muscle strength after lateral interbody fusion (LIF).

Summary Of Background Data: Muscle trauma and damage to intermuscular nerves due to dissection of the psoas are recognized perioperative complications of LIF. Although reduced leg strength is temporary in many cases, the underlying changes have not been studied in detail.

Methods: Leg muscle strength was measured quantitatively before LIF surgery and 1 week, 2 weeks, 3 weeks, 4 weeks, 8 weeks, and 12 weeks after surgery (n=38). Reduced muscle strength was defined as <80% of the preoperative measurement. The psoas position (PP%) was calculated from axial T2-weighted magnetic resonance images and compared with the degree of psoas and quadriceps muscle strength reduction at 1 week after surgery on the approach side. Twenty cases that underwent a posterior lumbar approach (posterior group) acted as controls.

Results: The proportion of patients with reduced psoas muscle strength 1 week after LIF was 60.5% on the approach side and 39.5% on the healthy side, versus 30.0% in the posterior group. The corresponding results for the quadriceps were 34.2%, 39.5%, and 25.0%, respectively. All cases had strength improvement on the approach side by 12 weeks postsurgery in the psoas and by 4 weeks postsurgery for the quadriceps. Psoas muscle strength and quadriceps strength at 1 week after surgery were correlated (ρ=0.57, P<0.001). There was a low inverse correlation between PP% and quadriceps strength at 1 week (ρ=-0.31, P<0.001).

Conclusions: Muscle strength declined in both the psoas and quadriceps muscle groups after LIF; however, the effect was temporary and strength recovered over time. Reduced postoperative quadriceps muscle strength may relate the position of the psoas muscle via increased irritation of the lumbar plexus during the splitting maneuver.
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http://dx.doi.org/10.1097/BSD.0000000000000756DOI Listing
April 2019

Subcutaneous rupture of the flexor hallucis longus tendon at the musculotendinous junction in a soccer player.

J Orthop Sci 2021 Mar 14;26(2):311-314. Epub 2018 Sep 14.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Japan.

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http://dx.doi.org/10.1016/j.jos.2018.08.011DOI Listing
March 2021

A kinematic and kinetic analysis of the hip and knee joints in patients with posterior tibialis tendon dysfunction; comparison with healthy age-matched controls.

Gait Posture 2018 10 5;66:228-235. Epub 2018 Sep 5.

Department of Rehabilitation Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho 465, Kawaramachi-Hirokoji, Kamigyo-ku, 602-8566 Kyoto, Japan; Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho 465, Kawaramachi-Hirokoji, Kamigyo-ku, 602-8566, Kyoto, Japan; Rehabilitation Unit, Kyoto Prefectural University Hospital 'Kajii-cho 465, Kawaramachi-Hirokoji, Kamigyo-ku, 602-8566, Kyoto, Japan.

Background: The biomechanical abnormalities in patients with posterior tibial tendon dysfunction (PTTD) have been described, but few studies have investigated biomechanical chains of adjacent joints. Therefore, we examined the gait pattern of the lower extremity in subjects with PTTD, focusing on the hip and knee joints.

Methods: We compared 19 PTTD patients (average age: 67.1) with 30 age-matched control subjects (average age: 65.1). Gait analysis was performed with a nine-camera motion-capture system and four force plates, using the Vicon Plug-In-Gait and Vicon Nexus software. Temporal-spatial parameters were compared between PTTD and control subjects, and motion and ground reaction force data were compared between the affected limb, the contralateral limb, and the right limb in control subjects.

Results: Subjects with PTTD had increased stance phase ratio and decreased stride length, cadence, and gait speed. The limbs of subjects with PTTD showed increased knee internal rotation at lording response, which was biased to abduction in the knee joint during the gait cycle, and irregular hip flexion and knee extension moment in the terminal stance, even under control of gait speed.

Significance: We believe that the subjects with PTTD have an increased risk of knee osteoarthritis in both the affected and contralateral limbs.
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http://dx.doi.org/10.1016/j.gaitpost.2018.08.040DOI Listing
October 2018

Total resection of any segment of the lateral meniscus may cause early cartilage degeneration: Evaluation by magnetic resonance imaging using T2 mapping.

Medicine (Baltimore) 2018 Jun;97(23):e11011

Department of Orthopaedics Department of Sports and Para-Sports Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

The aim of this study was to perform quantitative evaluation of degeneration of joint cartilage using T2 mapping in magnetic resonance imaging (MRI) after arthroscopic partial resection of the lateral meniscus.The subjects were 21 patients (23 knees) treated with arthroscopic partial resection of the lateral meniscus. MRI was performed for all knees before surgery and 6 months after surgery to evaluate the center of the lateral condyle of the femur in sagittal images for T2 mapping. Ten regions of interest (ROIs) on the articular cartilage were established at 10-degree intervals, from the point at which the femur shaft crossed the lateral femoral condyle joint to the articular cartilage 90° relative to the femur shaft. Preoperative and postoperative T2 values were evaluated at each ROI. Age, sex, body mass index, femorotibial angle, Tegner score, and amount of meniscal resection were evaluated when the T2 value increased more than 6% at 30°.T2 values at approximately 10 °, 20 °, 30 °, 40 °, 50 °, and 60 ° degrees relative to the anatomical axis of the femur were significantly greater postoperatively (3.1, 3.6, 5.5, 4.4, 5.0, 6.4%, respectively) than preoperatively. A >6% increase at 30° was associated with total resection of any segment of the meniscus.Degeneration of the articular cartilage, as shown by the disorganization of collagen arrays at positions approximately 10 °, 20 °, 30 °, 40 °, 50 °, and 60 ° relative to the anatomical axis of the femur, may start soon after arthroscopic lateral meniscectomy. Total resection of any segment of the lateral meniscus may cause T2 elevation of articular cartilage of lateral femoral condyle.
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http://dx.doi.org/10.1097/MD.0000000000011011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5999468PMC
June 2018

Treadmill Running Ameliorates Destruction of Articular Cartilage and Subchondral Bone, Not Only Synovitis, in a Rheumatoid Arthritis Rat Model.

Int J Mol Sci 2018 Jun 3;19(6). Epub 2018 Jun 3.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.

We analyzed the influence of treadmill running on rheumatoid arthritis (RA) joints using a collagen-induced arthritis (CIA) rat model. Eight-week-old male Dark Agouti rats were randomly divided into four groups: The control group, treadmill group (30 min/day for 4 weeks from 10-weeks-old), CIA group (induced CIA at 8-weeks-old), and CIA + treadmill group. Destruction of the ankle joint was evaluated by histological analyses. Morphological changes of subchondral bone were analyzed by μ-CT. CIA treatment-induced synovial membrane invasion, articular cartilage destruction, and bone erosion. Treadmill running improved these changes. The synovial membrane in CIA rats produced a large amount of tumor necrosis factor-α and Connexin 43; production was significantly suppressed by treadmill running. On μ-CT of the talus, bone volume fraction (BV/TV) was significantly decreased in the CIA group. Marrow star volume (MSV), an index of bone loss, was significantly increased. These changes were significantly improved by treadmill running. Bone destruction in the talus was significantly increased with CIA and was suppressed by treadmill running. On tartrate-resistant acid phosphate and alkaline phosphatase (TRAP/ALP) staining, the number of osteoclasts around the pannus was decreased by treadmill running. These findings indicate that treadmill running in CIA rats inhibited synovial hyperplasia and joint destruction.
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http://dx.doi.org/10.3390/ijms19061653DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6032207PMC
June 2018

Evaluation of femoral perfusion using dynamic contrast-enhanced MRI after simultaneous initiation of electrical stimulation and steroid treatment in an osteonecrosis model.

Electromagn Biol Med 2018 30;37(2):84-94. Epub 2018 Apr 30.

a Department of Orthopaedics, Graduate School of Medical Science , Kyoto Prefectural University of Medicine , Kyoto , Japan.

This study aimed to evaluate femoral perfusion using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for two weeks after the simultaneous initiation of electrical stimulation (ES) and steroid treatment in a steroid-induced osteonecrosis (ON) model. A single dose of methylprednisolone was injected into 14 rabbits. Seven rabbits underwent ES (ES group), and seven rabbits did not (control group). DCE-MRI was performed before steroid administration and 1, 5, 10, and 14 days after steroid administration. Regions of interest were set in the bilateral proximal femora. The enhancement ratio, initial slope, and area under the curve were analyzed. These parameters were evaluated after steroid administration in each group and between the two groups, and the ratios of ON in both groups were compared. In the control group, the minimum values of all parameters decreased significantly after steroid administration (P < 0.05), but in the ES group, the parameters did not decrease. In the ES group, all parameter values were significantly increased on the 10th and 14th days (P < 0.05). All parameter values in the ES group were significantly higher than those in the control group on the 14th day (P < 0.05). In the control group, ON was detected in three of five rabbits (in three of ten femora). In the ES group, ON was not detected. These results suggest that increased femoral blood flow elicited by ES may be related to ON prevention after steroid administration.
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http://dx.doi.org/10.1080/15368378.2018.1466310DOI Listing
October 2018

Towards patient-specific medializing calcaneal osteotomy for adult flatfoot: a finite element study.

Comput Methods Biomech Biomed Engin 2018 Mar 15;21(4):332-343. Epub 2018 Mar 15.

a Department of Robotics , Ritsumeikan University , Shiga , Japan.

Clinically in medializing calcaneal osteotomy (MCO), foot and ankle surgeons are facing difficulties in choosing appropriate surgical parameters due to the individual differences in deformities among flatfoot patients. Traditional cadaveric studies have provided important information regarding the biomechanical effects of tendons, ligaments, and plantar fascia, but limitations have been reached when dealing with individual differences and tailoring patient-specific surgeries. Therefore, this study aimed at implementing the finite element (FE) method to investigate the effect of different MCO parameters to help foot and ankle surgeons performing patient-specific surgeries. This study constructed FE models of a flatfoot and a healthy foot based on computed tomography (CT) images. After validating the FE models with experimental measurements, differences in plantar stress were compared between two models and a criterion was established for evaluating the performance of surgical simulations. Four MCO parameters were then studied through FE simulations. Results suggested that the transverse angle, β, and translation distance, d, affected surgical performance. Therefore, special attentions may be recommended when choosing these two parameters clinically. However, the sagittal angle, α, and osteotomy position, p, were found to have less effect on the MCO performance.
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http://dx.doi.org/10.1080/10255842.2018.1452202DOI Listing
March 2018

Early detection of osteoarthritis in rabbits using MRI with a double-contrast agent.

BMC Musculoskelet Disord 2018 03 13;19(1):81. Epub 2018 Mar 13.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 602-8566 465, Kajiicho, Kamigyo-ku Kyoto-shi, Kyoto, Japan.

Background: Articular cartilage degeneration has been evaluated by magnetic resonance imaging (MRI). However, this method has several problems, including its time-consuming nature and the requirement of a high magnetic field or specialized hardware. The purpose of this study was to sequentially assess early degenerative changes in rabbit knee articular cartilage using MRI with a new double-contrast agent.

Methods: We induced osteoarthritis (OA) in the right knee of rabbits by anterior cruciate ligament transection and partial medial meniscectomy. Proton density-weighted images and T-calculated images were obtained before and after contrast agent injection into the knee. The signal intensity ratio (SIR) values on the proton density-weighted images were calculated by dividing the signal intensity of the articular cartilage by that of joint fluid. Six rabbits were examined using MRI at 2 (designated 2-w OA) and 4 weeks (4-w OA) after the operation. Histological examination was performed 4 weeks after the operation. One rabbit was histologically examined 2 weeks after the operation. The control consisted of six rabbits that were not subjected to the operation. The SIR values, T values and the thicknesses of the cartilage of the 2-w OA, 4-w OA and the control before and after contrast agent injection were analyzed. The Mankin score and OARSI (Osteoarthritis Research Society International) score were used for the histological evaluation.

Results: Significant differences in the SIR and T values of the medial and lateral condyles of the femur were found between the control and the 4-w OA only after contrast agent injection. No significant differences were found in the SIR and T values before contrast agent injection between the control, the 2-w OA and 4-w OA. The thickness of the articular cartilage revealed no significant differences. In the histological assessment, the Mankin score and OARSI score sequentially increased from the control to the 4-w OA.

Conclusion: We evaluated the SIR and T values of the knees in a rabbit OA model and a control model using a new double-contrast agent. MRI with this agent enabled OA detection earlier than using conventional MRI.
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http://dx.doi.org/10.1186/s12891-018-2002-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5851162PMC
March 2018

Sequential variation in brain functional magnetic resonance imaging after peripheral nerve injury: A rat study.

Neurosci Lett 2018 04 7;673:150-156. Epub 2018 Mar 7.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 602-8566 465, Kajiicho, Kamigyo-ku Kyoto-shi, Kyoto, Japan. Electronic address:

Although treatment protocols are available, patients experience both acute neuropathic pain and chronic neuropathic pain, hyperalgesia, and allodynia after peripheral nerve injury. The purpose of this study was to identify the brain regions activated after peripheral nerve injury using functional magnetic resonance imaging (fMRI) sequentially and assess the relevance of the imaging results using histological findings. To model peripheral nerve injury in male Sprague-Dawley rats, the right sciatic nerve was crushed using an aneurysm clip, under general anesthesia. We used a 7.04T MRI system. T weighted image, coronal slice, repetition time, 7 ms; echo time, 3.3 ms; field of view, 30 mm × 30 mm; pixel matrix, 64 × 64 by zero-filling; slice thickness, 2 mm; numbers of slices, 9; numbers of average, 2; and flip angle, 8°. fMR images were acquired during electrical stimulation to the rat's foot sole; after 90 min, c-Fos immunohistochemical staining of the brain was performed in rats with induced peripheral nerve injury for 3, 6, and 9 weeks. Data were pre-processed by realignment in the Statistical Parametric Mapping 8 software. A General Linear Model first level analysis was used to obtain T-values. One week after the injury, significant changes were detected in the cingulate cortex, insular cortex, amygdala, and basal ganglia; at 6 weeks, the brain regions with significant changes in signal density were contracted; at 9 weeks, the amygdala and hippocampus showed activation. Histological findings of the rat brain supported the fMRI findings. We detected sequential activation in the rat brain using fMRI after sciatic nerve injury. Many brain regions were activated during the acute stage of peripheral nerve injury. Conversely, during the chronic stage, activation of the amygdala and hippocampus may be related to chronic-stage hyperalgesia, allodynia, and chronic neuropathic pain.
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http://dx.doi.org/10.1016/j.neulet.2018.03.003DOI Listing
April 2018

Extracorporeal Shock Wave Therapy for an Adolescent Patient with Calcific Tendinopathy of Posterior Tibial Tendon: A Case Report.

Prog Rehabil Med 2018 10;3:20180004. Epub 2018 Mar 10.

Department of Orthopaedics, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Background: We report a rare case of calcific tendinopathy in the posterior tibial tendon (PTT) at the navicular insertion.

Case: Conservative treatments other than extracorporeal shock wave therapy (ESWT) were ineffective. Calcium deposition disappeared from the PTT on plain radiographs at 6 months after ESWT.

Discussion: In this case, a 14-year-old boy with calcific tendinopathy of the PTT who had not benefited from conservative treatments was effectively treated using ESWT.
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http://dx.doi.org/10.2490/prm.20180004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7365174PMC
March 2018

Usefulness of Sweep Imaging With Fourier Transform for Evaluation of Cortical Bone in Diabetic Rats.

J Magn Reson Imaging 2018 08 23;48(2):389-397. Epub 2018 Jan 23.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Background: Diabetes decreases bone strength, possibly because of cortical bone changes. Sweep imaging with Fourier transform (SWIFT) has been reported to be useful for cortical bone evaluation.

Purpose: To evaluate cortical bone changes in diabetic rats using SWIFT, assess the usefulness of this technique through comparisons with microcomputed tomography (μCT) and conventional MRI, and clarify the mechanism underlying cortical bone changes using histomorphometry STUDY TYPE: Animal cohort.

Animal Model: 8-week-old male Wistar/ST rats (N = 36) were divided into diabetes (induced by streptozotocin injection) and control groups.

Field Strength/sequence: 7.04T MRI, SWIFT.

Assessment: Six animals from each group were sacrificed at 2, 4, and 8 weeks after injection. Tibial bones were extracted and evaluated using μCT and MRI. The cortical bone mineral density (BMD) was measured using μCT. Proton density-weighted imaging (PDWI) and SWIFT were also performed. The signal-to-noise ratio (SNR) was calculated for each acquisition. The bone formation rate was evaluated using histomorphometry.

Statistical Tests: Findings at each timepoint were compared using Mann-Whitney U-tests.

Results: Cortical BMD was significantly lower in the diabetes group than in the control group only at 8 weeks (P < 0.05). At all timepoints, PDWI-SNR showed no significant differences between groups (P = 0.59, 0.70, and 0.82 at 2, 4, and 8 weeks, respectively). SWIFT-SNR was significantly lower in the diabetes group than in the control group (P < 0.05 at 2 and 4 weeks and P < 0.01 at 8 weeks), and the bone formation rate was significantly lower in the diabetes group than in the control group (P < 0.01 for all).

Data Conclusion: SWIFT can detect cortical bone changes even before a decline in the cortical BMD in a diabetic model.

Level Of Evidence: 1 Technical Efficacy: Stage 3 J. MAGN. RESON. IMAGING 2018;48:389-397.
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http://dx.doi.org/10.1002/jmri.25955DOI Listing
August 2018

Fixed-flexion view X-ray of the knee superior in detection and follow-up of knee osteoarthritis.

Medicine (Baltimore) 2017 Dec;96(49):e9126

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine Department of Orthopaedics, Kyoto Interdisciplinary Institute Hospital of Community Medicine Department of Sports and Para-Sports Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine Kobayashi Orthopaedic Clinic Department of Biostatistics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.

A fixed flexion view (FFV) is useful for evaluating joint space when assessing the severity of osteoarthritis (OA) of the knee. We analyzed changes in joint space revealed by standing extended view (SEV) and FFV over a mean 4 years, to compare both views on their capacity to measure joint space width accurately at particular time points during follow-up.SEV and FFV images were acquired in patients with knee OA. The 81 patients (157 knees) followed up for ≥24 months were selected as study subjects. Medial joint space widths (MJSW), Kellgren-Lawrence (KL) grades, and reductions in MJSW on SEV (ΔSEV) and FFV (ΔFFV) were compared in knees evaluated by SEV and FFV.At both time-points, mean MJSW was significantly lower by FFV than by SEV. Mean MJSW was significantly lower at follow-up than at first examination by both SEV and FFV. At both time-points, the KL grade was higher by FFV than by SEV group. The ΔFFV was significantly greater than the ΔSEV. ΔSEV did not differ significantly among KL grades, but ΔFFV was significantly greater in patients with KL grade II than in patients with other KL grades.FFV is not only useful for evaluating joint space in knees with OA, but also for accurately evaluating the progression of OA. The risk of rapid progression of knee OA may be higher in patients with KL grade II, as determined by FFV. FFV may be superior to SEV in determining appropriate treatment strategies for knee OA.
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http://dx.doi.org/10.1097/MD.0000000000009126DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5728966PMC
December 2017

Magnetic resonance imaging findings of chronic plantar fasciitis before and after extracorporeal shock wave therapy.

Foot (Edinb) 2017 Dec 26;33:25-28. Epub 2017 Oct 26.

Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.

Introduction: The objective of this study is to examine the relationships between treatment outcome and changes in magnetic resonance (MR) imaging findings after extracorporeal shock wave therapy (ESWT) for chronic plantar fasciitis.

Methods: The subjects were 23 feet of 23 patients of refractory plantar fasciitis. The mean age was 53.7 years. The thickness of the plantar fascia (PF) and findings of a high-signal intensity area (HSIA) inside the PF, edema around the PF, and bone marrow edema (BME) of the calcaneus were investigated on MR images. The Japanese Society for Surgery of the Foot (JSSF) ankle-hindfoot scale and a visual analogue scale (VAS) were used. Correlations between an improvement in symptoms and one in the MRI findings were analyzed.

Results: The mean thickness of the PF was 4.4±1.6mm before ESWT and 4.6±1.8mm six months after ESWT. After ESWT, there was a decrease in the numbers of feet showing HSIA inside the PF from 15 to 6, in edema around the PF from 16 to 2, and in BME of the calcaneus from 11 to 4. Clinical outcomes improved with ESWT from 70.3±5.5 to 88.6±9.1 points (JSSF), 74.1±25.3 to 28.5±24.4 points (VAS), respectively. Improvements in symptoms according to the JSSF and VAS scores and improvement in edema around the PF on MR images showed a significant correlation.

Conclusions: Edema around the PF improved significantly in association with an improvement in symptoms after ESWT.
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http://dx.doi.org/10.1016/j.foot.2017.10.002DOI Listing
December 2017

Angiotensin 1-7 stimulates brown adipose tissue and reduces diet-induced obesity.

Am J Physiol Endocrinol Metab 2018 02 24;314(2):E131-E138. Epub 2017 Oct 24.

Department of Pediatrics, Kyoto Prefectural University of Medicine, Graduate School of Medical Science , Kyoto , Japan.

The renin-angiotensin system is a key regulator of metabolism with beneficial effects of the angiotensin 1-7 (Ang 1-7) peptide. We hypothesized that the antiobesity effect of Ang 1-7 was related to the stimulation of brown adipose tissue (BAT). We administered Ang 1-7 (0.54 mg kg day) for 28 days via implanted micro-osmotic pumps to mice with high-fat diet (HFD)-induced obesity. Ang 1-7 treatment reduced body weight, upregulated thermogenesis, and ameliorated impaired glucose homeostasis without affecting food consumption. Furthermore, Ang 1-7 treatment enlarged BAT and the increased expression of UCP1, PRDM16, and prohibitin. Alterations in PRDM16 expression correlated with increased AMPK and phosphorylation of mTOR. Ang 1-7 treatment elevated thermogenesis in subcutaneous white adipose tissue without altering UCP1 expression. These changes occurred in the context of decreased lipid accumulation in BAT from HFD-fed mice, preserved insulin signaling concomitant with phosphorylation of hormone-sensitive lipase and decreased expression of perilipin. These data suggest that Ang 1-7 induces brown adipocyte differentiation leading to upregulation of thermogenesis and improved metabolic profile in diet-induced obesity. Enhancing Ang 1-7 action represents a promising therapy to increase BAT and to reduce the metabolic complications associated with diet-induced obesity.
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http://dx.doi.org/10.1152/ajpendo.00192.2017DOI Listing
February 2018