Publications by authors named "Kohei Kamada"

Article Synopsis
  • Diagnosing chronic lateral ankle instability (CLAI) involves assessing medical history, physical exams, and imaging techniques, but the best method is still debated.
  • Recent advancements include the anterior drawer test for ligament insufficiency and the use of ultrasonography, which is less invasive and provides dynamic assessments.
  • Combining physical exams with imaging, like MRI, is crucial for accurate CLAI diagnosis, and future studies should aim to standardize testing methods.
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Article Synopsis
  • The study investigates the effectiveness of platelet-rich plasma (PRP) injections as a treatment for knee osteoarthritis (KOA), focusing on multiple injections and factors influencing pain relief.* -
  • An analysis of over 1,000 knees found that patient age, pain severity before treatment, the Kellgren-Lawrence (KL) grade of osteoarthritis, and the number of PRP injections affected the reduction in pain measured by visual analog scale (VAS) scores.* -
  • Results suggest that younger patients or those with severe pain before treatment benefit most from PRP injections; three injections are recommended for early-stage KOA, while more may be needed for advanced cases.*
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The objectives of this study were to evaluate the reliability of cartilage T2 relaxation time measurements and to identify focal changes in T2 relaxation on the affected knee from 6 to 24 months after anatomic anterior cruciate ligament reconstruction (ACLR). Data from 41 patients who received anatomic ACLR were analyzed. A bilateral 3.

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We formulate scalar field theories coupled nonconformally to gravity in a manifestly frame-independent fashion. Physical quantities such as the S matrix should be invariant under field redefinitions, and hence can be represented by the geometry of the target space. This elegant geometric formulation, however, is obscured when considering the coupling to gravity because of the redundancy associated with the Weyl transformation.

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A chiral chemical potential present in the early Universe can source helical hypermagnetic fields through the chiral plasma instability. If these hypermagnetic fields survive until the electroweak phase transition, they source a contribution to the baryon asymmetry of the Universe. In this Letter, we demonstrate that lepton flavor asymmetries above |μ|/T∼9×10^{-3} trigger this mechanism even for vanishing total lepton number.

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Medial meniscus posterior root tears (MMPRT) are often associated with osteoarthritis (OA) progression and subchondral bone insufficiency fractures. This study aimed to develop the first MMPRT mouse model. The MMPRT model was created by sectioning the medial meniscus posterior root of 12-week-old CL57BL/6J male mice under stereomicroscopic observation.

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Introduction: Although anterior cruciate ligament reconstruction (ACLR) is considered a successful procedure, residual pivot-shift after surgery remains to be solved. The purpose of this study was to comprehensively evaluate the risk factors of residual pivot-shift after anatomic double-bundle (DB) ACLR.

Materials And Methods: A total of 164 patients who underwent primary anatomic DB-ACLR between January 2014 and December 2019 and screw removal after the index ACLR in our hospital were included in this retrospective case-control study.

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Purpose: To compare the biomechanical strength of different fixation configurations using suspensory buttons in a soft-tissue quadriceps tendon (QT) grafts in anterior cruciate ligament (ACL) reconstruction.

Methods: Forty bovine QTs, 6-cm long and 10-mm wide, were allocated into four groups with different suture configurations using suspensory buttons (n = 10 in each group): Group A, a baseball suture with a knot tied to the continuous loop with a suspensory button; Group B, same configuration as in Group A but with the knot tied at the opposite end of the baseball suture; Group C, a continuous loop with a suspensory button stitched directly to the QT with simple sutures, and Group D, a baseball suture tied directly to a suspensory button. Biomechanical testing was performed by preloading followed by cyclic loading for 500 cycles between 10 and 100 N.

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Background: The Segond fracture can be observed in patients with an anterior cruciate ligament (ACL) tear. It is unclear whether the Segond fracture affects clinical outcomes after ACL reconstruction.

Purpose: To investigate whether the presence of a concomitant Segond fracture affects clinical outcomes after ACL reconstruction and to compare clinical outcomes when a Segond fracture is repaired surgically or left unrepaired.

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Adipose-derived regenerative cells (ADRCs) are non-cultured heterogeneous or mixed populations of cells obtained from adipose tissue by collagenase digestion. The injection of ADRCs have been tried clinically for the treatment of osteoarthritis (OA). The purpose of this study was to evaluate the effect of intra-articular transplantation of human ADRCs on OA progression in mice and the effect of ADRCs on macrophage polarization.

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We present a leptogenesis mechanism based on the standard type-I seesaw model that successfully operates at right-handed-neutrino masses as low as a few hundred TeV. This mechanism, which we dub wash-in leptogenesis, does not require any CP violation in the neutrino sector and can be implemented even in the regime of strong wash-out. The key idea behind wash-in leptogenesis is to generalize standard freeze-out leptogenesis to a nonminimal cosmological background in which the chemical potentials of all particles not in chemical equilibrium at the temperature of leptogenesis are allowed to take arbitrary values.

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Permanent patellar dislocation with tibiofemoral joint osteoarthritis is a relatively rare condition. To treat this condition, total knee arthroplasty with proximal or distal realignment of the extensor mechanism has been reported. We report a challenging case of an 80-year-old woman diagnosed with permanent patellar dislocation with tibiofemoral joint osteoarthritis treated by a mobile bearing total knee arthroplasty utilizing navigation system.

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