Publications by authors named "Yasuyuki Kawaguchi"
Article Synopsis
- The case report focuses on using musculoskeletal ultrasound imaging to assess and improve knee stiffness in a patient after total knee arthroplasty.
- An 82-year-old woman was treated for limited knee flexion affecting her daily activities, and ultrasound helped identify the issue as decreased tissue movement in the suprapatellar pouch.
- After ultrasound-guided passive manipulation, her knee flexion increased and she regained the ability to climb stairs, showing significant improvement in mobility and daily functions.
Background: Ehlers-Danlos syndrome (EDS) is a connective tissue disorder characterized by skin hyperextensibility, joint hypermobility, and tissue friability. Hypermobile type Ehlers-Danlos syndrome (hEDS) is considered one of the EDS subtypes characterized by generalized joint hypermobility. Although there have been a few case reports which described surgical considerations for anterior cruciate ligament (ACL) reconstructions in patients with other types of EDS, no reports have described those in patients with hEDS.
View Article and Find Full Text PDFIntroduction: Currently, various studies have been reported to regenerate the meniscus tissue in a large defect after partial meniscectomy using biological or synthetic scaffolds with or without fibrochondrocytes. However, the clinical utility of those treatments has not been established as of yet.
Hypothesis: Purposes of this study were to develop a sheep model to evaluate feasibility of this new surgical strategy to treat the irreparable meniscus injury, and to test the hypothesis that implantation of autogenous meniscal fragments wrapped with a fascia sheath may significantly induce fibrocartilage regeneration in a large meniscal defect in the sheep model.
Introduction: Implantation of autogenous meniscal fragments wrapped with a fascia sheath significantly enhances fibrocartilage regeneration in vivo in defect cases at 12 weeks after implantation. The specific effects of the implanted autologous living chondrocytes and meniscal matrix have not been elucidated, however. The aim of this study was to clarify the role of autologous living chondrocytes contained in the meniscal matrix in in vivo meniscus regeneration induced by in situ meniscus fragment implantation.
View Article and Find Full Text PDFBackground: In several anatomic single-bundle anterior cruciate ligament (ACL) reconstruction (ASB-ACLR) procedures, the femoral and tibial tunnel apertures are created at different locations within the native ACL attachment area.
Hypothesis: Graft length changes during knee motion will be different among ASB-ACLR procedures with different femoral and tibial tunnel aperture locations.
Study Design: Controlled laboratory study.
Background: Many tissue-engineered methods for meniscal repair have been studied, but their utility remains unclear.
Hypothesis: Implantation of low-endotoxin, ultra-purified alginate (UPAL) gel without cells could induce fibrocartilage regeneration on meniscal defects in rabbits.
Study Design: Controlled laboratory study.
Background: There is controversy regarding the efficacy of remnant tissue preservation on graft healing in anterior cruciate ligament (ACL) reconstruction.
Hypothesis: The preserved remnant tissue will (1) adhere to the graft surface and undergo a remodeling process, (2) accelerate graft revascularization, (3) increase the number of graft mechanoreceptors by 4 weeks, and (4) improve anteroposterior knee laxity and structural properties of the graft by 12 weeks.
Study Design: Controlled laboratory study.
Background: Clinical utility of remnant tissue preservation after single-bundle anterior cruciate ligament (ACL) reconstruction has not been established. In addition, no studies have evaluated the clinical utility of remnant preservation after anatomic double-bundle ACL reconstruction.
Hypothesis: The study hypotheses were as follows: (1) Subjective and functional clinical results may be comparable between anatomic double-bundle reconstructions that preserve the remnant tissue and those that resect the remnant tissue, (2) postoperative knee stability and the second-look arthroscopic evaluation may be significantly more favorable with the remnant-preserving reconstruction, and (3) the degree of the initial graft coverage may significantly affect postoperative knee stability.
Article Synopsis
- The study aimed to determine how different fiber areas of the anterior cruciate ligament (ACL) attach to the femur contribute to resisting tibial movements, particularly in terms of anterior drawer and rotational forces.
- Eight human knees were examined through a sequential cutting method that measured restraining forces after cutting various areas of the ACL, including central dense fibers and fan-like extensions.
- Results showed that the central fibers significantly resisted anterior drawer forces, accounting for 66% to 84% of the load, while the anterior and posterior extensions provided minimal resistance, suggesting that ACL graft placement should focus on the central area to effectively mimic natural resistance.
Background: In the anatomic double-bundle ACL reconstruction, 2 femoral tunnel positions are particularly critical to obtain better clinical results. Recently, a few studies have reported quantitative identification methods for posterolateral (PL) bundle reconstruction. Concerning anteromedial (AM) bundle reconstruction, however, no quantitative clinically available methods to insert a guide wire at the center of the direct attachment of the AM mid-substance fibers have been reported to date.
View Article and Find Full Text PDFBackground: We have developed crosslinked salmon-derived atelocollagen sponge, which has a denaturation temperature of 47 degrees Celsius. The purpose of this study is to evaluate the fundamental in vivo efficacy of the osteogenic protein (OP) -1 containing salmon-derived collagen sponge disc (SCS) on cartilage regeneration, using a rabbit model.
Methods: A total of 24 rabbits were used in this study.
Background: Tunnel enlargement and coalition following double-bundle anterior cruciate ligament (ACL) reconstruction with hamstring tendon autografts has not yet been sufficiently studied.
Hypothesis: The incidence and the degree of femoral tunnel enlargement will be significantly greater than those for tibial tunnel enlargement after anatomic double-bundle ACL reconstruction using hamstring tendon autografts. There will be no significant correlation between tunnel enlargement and coalition and the postoperative knee laxity.
Aim: To compare tissue concentrations of flurbiprofen resulting from topical application and oral administration according to the regulatory approved dosing guidelines.
Method: Sixteen patients were included in this study. Each patient was randomly assigned to the topical application or oral administration group.
Purpose: The purpose of this pilot study was to evaluate the preliminary results of an anatomic double-bundle anterior cruciate ligament (ACL) reconstruction procedure with ligament remnant tissue preservation.
Methods: By use of the transtibial technique, 2 doubled semitendinosus tendons were grafted into 4 tunnels created at the center of each bundle attachment, penetrating the ACL remnant tissue. In total, 44 patients (27 male and 17 female patients) with an isolated ACL injury underwent ACL reconstruction with this procedure.
Purpose: Authors have hypothesized that the incidence and the degree of femoral tunnel enlargement after the hamstring ACL reconstruction may be significantly less in the anatomic double-bundle procedure than in single-bundle procedure. The purpose of this study is to test this hypothesis.
Methods: Seventy-two patients who underwent single-bundle reconstruction (Group S) and 97 patients who underwent anatomic double-bundle reconstruction (Group D) were followed up for 2 years after surgery.
We have developed crosslinked salmon-derived atelocollagen (SC) sponge, which has a denaturation temperature of 47°C. Sixty-four knees of 32 mature rabbits were randomly divided into 4 groups after creating an osteochondral defect in the femoral trochlea. Defects in Groups I, II, and III were filled with the crosslinked SC sponge, the crosslinked porcine collagen (PC) sponge, and the non-crosslinked PC sponge, respectively.
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