Hideki Yoshikawa

Publications (481)1164.39 Total impact

• Article: Posterior Sliding of the Femur During Stair Ascending and Descending in a High-Flex Posterior Stabilized Total Knee Arthroplasty.

  Norimasa Shimizu, Tetsuya Tomita, Takaharu Yamazaki, Hideki Yoshikawa, Kazuomi Sugamoto
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  ABSTRACT: This study investigated the anteroposterior stability of the femur during stair motions. We examined 18 knees with a clinically successful high-flexion posterior stabilized total knee arthroplasty to evaluate the in vivo kinematics of stair ascending and descending using two- to three-dimensional registration. Posterior sliding of the femur was observed while shifting weight to the leg during stair ascending and descending in almost all knees. Anterior tibial post impingement was observed in 10 knees when the knee was extended in stair ascending, whereas in stair descending, the impingement was observed in 14 knees when posterior sliding of the femur occurred. The impingement contributed to the stabilization of the knee during stair motion; however, impingement may result in additional polyethylene wear and tibial post failure.
  The Journal of arthroplasty 05/2013; · 1.79 Impact Factor
• Article: TNF inhibitors induce discoid fibrosis in the sublining layers of the synovium with degeneration of synoviocytes in rheumatoid arthritis.

  Shunsei Hirohata, Tetsuya Tomita, Hideki Yoshikawa, Masahisa Kyogoku
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  ABSTRACT: We determined the characteristic features of synovial tissues of rheumatoid arthritis (RA) patients treated by TNF inhibitors in order to delineate their mechanism of action. Synovial tissues were obtained during the joint surgical operations from 12 RA patients who had been treated with TNF inhibitors in addition to disease modifying antirheumatic drugs (DMARDs) for at least 5 months (5-25 months) (RA-TNFinh), and from 12 RA patients who had been treated with DMARDs alone (RA-DMARD), and were evaluated under light microscopy. There were no significant differences in disease duration, serum CRP levels, DAS28, Steinbrocker's stages on X-ray and treatment regimen except for TNF inhibitors between RA-TNFinh and RA-DMARD. The most prominent changes in the synovium from RA-TNFinh were discoid fibrosis in the subliming layers of the synovium with degeneration and detachment of synoviocytes and marked decrease in vasculatures. There was no significant difference in these synovial features between RA patients with infliximab and those with etanercept. Interestingly, appearance of osteoclasts was observed in RA-TNFinh (3 out of 12 patients) and in RA-DMARD (1 out of 12 patients). These results indicate that not only infliximab, but etanercept might have direct actions on synovial cells in the deep lining layers of the synovium, leading to the discoid fibrosis thereof. Moreover, the data confirm that the deep lining or sublining layers of the synovium are the most important portions that steer the disease process of RA synovitis.
  Rheumatology International 04/2013; · 1.88 Impact Factor
• Article: Does cubitus varus cause morphologic and alignment changes in the elbow joint?

  Yohei Kawanishi, Junichi Miyake, Toshiyuki Kataoka, Shinsuke Omori, Kazuomi Sugamoto, Hideki Yoshikawa, Tsuyoshi Murase
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  ABSTRACT: BACKGROUND: In cubitus varus after pediatric supracondylar fracture, late development of trochlear deformity causing additional varus angulation and joint misalignment relating to late complications of the tardy ulnar nerve palsy or posterolateral rotatory instability have been suggested. However, it is unclear whether these morphologic and alignment changes of the elbow joint occur in cubitus varus. The object of this study was to investigate morphologic changes of the bones and alignment changes of the elbow joint in longstanding cubitus varus using 3-dimensional computer bone models created from computed tomography data. MATERIALS AND METHODS: We studied 14 patients with longstanding cubitus varus after pediatric supracondylar fractures. Three-dimensional bone models of the bilateral humerus, radius, and ulna were created from computed tomography data. We compared the morphology and alignment of the elbow joint between the affected side and contralateral unaffected side. RESULTS: The posterior trochlea, distal part of the lateral capitellum, diameters of the radial head, and articular surface of the ulna in cubitus varus were larger than those of the contralateral elbow. In the ulna, the convex portion of the trochlear notch shifted laterally in cubitus varus. Joint alignment in cubitus varus was affected by a shift of the ulna to a more distal and medial position with external rotation and flexion. CONCLUSIONS: In longstanding cubitus varus, the morphology and alignment of the elbow joint are observed to differ from those of the normal side.
  Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.] 04/2013; · 1.93 Impact Factor
• Article: Surgical treatment for osteoporotic vertebral collapse with neurological deficits: Retrospective comparative study of three procedures-anterior surgery versus posterior spinal shorting osteotomy versus posterior spinal fusion using vertebroplasty.

  Masafumi Kashii, Ryoji Yamazaki, Tomoya Yamashita, Shinya Okuda, Takahito Fujimori, Yukitaka Nagamoto, Yuichi Tamura, Takenori Oda, Tetsuo Ohwada, Hideki Yoshikawa, Motoki Iwasaki
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  ABSTRACT: PURPOSE: In general, osteoporotic vertebral collapse (OVC) with neurological deficits requires sufficient decompression of neural tissues to restore function level in activities of daily living (ADL). However, it remains unclear as to which procedure provides better neurological recovery. The primary purpose of this study was to compare neurological recovery among three typical procedures for OVC with neurological deficits. Secondary purpose was to compare postoperative ADL function. METHODS: We retrospectively reviewed data for 88 patients (29 men and 59 women) with OVC and neurological deficits who underwent surgery. Three typical kinds of surgical procedures with different decompression methods were used: (1) anterior direct neural decompression and reconstruction (AR group: 27 patients), (2) posterior spinal shorting osteotomy with direct neural decompression (PS group: 36 patients), and (3) posterior indirect neural decompression and short-segment spinal fusion combined with vertebroplasty (VP group: 25 patients). We examined clinical results regarding neurological deficits and function level in ADL and radiological results. RESULTS: The mean improvement rates for neurological deficits and ADL function level were 60.1 and 55.0 %, respectively. There were no significant differences among three groups in improvement rates for neurological deficits or ADL function level. The VP group had a significantly lower estimated mean blood loss (338 mL) and mean duration of surgery (229 min) than both the AR and PS groups (p < 0.001). CONCLUSION: Direct neural decompression is not always necessary, and the majority of patients can be treated with a less-invasive procedure such as short-segment posterior spinal fusion with indirect decompression combined with vertebroplasty. The high-priority issue is careful evaluation of patients' general health and osteoporosis severity, so that the surgeon can choose the procedure best suited for each patient.
  European Spine Journal 04/2013; · 1.97 Impact Factor
• Article: Prevalence of gastroesophageal reflux disease symptoms and related factors in patients with rheumatoid arthritis.

  Akihide Nampei, Kenrin Shi, Kosuke Ebina, Tetsuya Tomita, Kazuomi Sugamoto, Hideki Yoshikawa, Makoto Hirao, Jun Hashimoto
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  ABSTRACT: Gastroesophageal reflux disease (GERD) is common in patients with many chronic diseases, but has not been well recognized in rheumatoid arthritis (RA). We investigated the prevalence of GERD symptoms in 278 outpatients with RA and their association with such clinical factors as age, sex, height, weight, body mass index, medications drugs, and functional status evaluated by the Modified Health Assessment Questionnaire (MHAQ). GERD symptoms were evaluated by Frequency Scale for the Symptoms of GERD (FSSG). The mean FSSG score for all patients was 5.6, and 82 patients were considered to have GERD symptoms (FSSG score ≥8), thus the overall prevalence of GERD symptoms was 29.5%. MHAQ score and height were significantly higher and lower, respectively, and prednisolone usage was significantly more in the patients with GERD symptoms than those without. These three clinical factors were also significantly associated with GERD symptoms by univariate logistic regression. Multivariate logistic regression analysis demonstrated that MHAQ was the only clinical factor related to GERD symptoms. In conclusion, the prevalence of GERD symptoms in RA patients was high and strongly associated with decreased functional status, suggesting that physicians should pay attention to GERD symptoms in RA management, especially for patients with low functional status.
  Journal of Clinical Biochemistry and Nutrition 03/2013; 52(2):179-84. · 1.98 Impact Factor
• Article: Factors in High-Flex Posterior Stabilized Fixed-Bearing Total Knee Arthroplasty Affecting In Vivo Kinematics and Anterior Tibial Post Impingement During Gait.

  Masashi Tamaki, Tetsuya Tomita, Takaharu Yamazaki, Hideki Yoshikawa, Kazuomi Sugamoto
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  ABSTRACT: One of the most important issues in high-flex posterior stabilized total knee arthroplasty (TKA) is anterior tibial post impingement. We examined 20 knees and 2 TKA designs to evaluate the in vivo kinematics during gait using fluoroscopic image analysis. The AP positions in both stance and swing phases were significantly larger and more anterior in J-curved design TKA compared with Single radius design TKA. Anterior tibial post impingement was observed in five knees implanted with Legacy-flex, and in four of the five knees they were not hyperextended. No impingement was observed with NRG. Less constraint and tibial posterior slope might lead to large AP translations and anterior tibial post impingement. Implant design and operative procedures for high-flexion TKAs affect the in vivo kinematics and the occurrence of anterior tibial post impingement.
  The Journal of arthroplasty 02/2013; · 1.79 Impact Factor
• Article: In-vivo biomechanical analysis of osteochondritis dissecans of the humeral trochlea: a case report.

  Junichi Miyake, Toshiyuki Kataoka, Tsuyoshi Murase, Hideki Yoshikawa
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  ABSTRACT: Osteochondritis dissecans (OCD) of the humeral trochlea can occur among adolescent gymnasts or throwing athletes. However, the natural history and treatment strategy remain unclear because of its low incidence. The aim of this report was to determine the biomechanical influence of trochlear OCD on the elbow joint by analyzing three-dimensional in-vivo joint biomechanics in a trochlear OCD case.
  Journal of pediatric orthopaedics. Part B / European Paediatric Orthopaedic Society, Pediatric Orthopaedic Society of North America 02/2013; · 0.66 Impact Factor
• Article: Radiofrequency ablation for treatment for osteoid osteoma of the scapula using a new three-dimensional fluoroscopic navigation system.

  Kiyoshi Okada, Akira Myoui, Nobuyuki Hashimoto, Satoshi Takenaka, Hisao Moritomo, Tsuyoshi Murase, Hideki Yoshikawa
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  ABSTRACT: Osteoid osteoma is a relatively common benign skeletal tumor. The traditional standard treatment has been surgical resection of the nidus. Recently, computed tomography (CT)-guided radiofrequency ablation (RFA) has gained favor as a more precise alternative due to potentially less bone destruction. However, CT-guided RFA is limited in treatment for osteoid osteoma involving complex anatomic structures such as cervical spine, pelvis, or scapula because of difficulty in approach and proximity to neurovascular structures. To solve this problem, we investigated RFA using a new real-time three-dimensional fluoroscopic navigation system. We report its technical procedure and use in a rare case of osteoid osteoma of the scapula.
  European Journal of Orthopaedic Surgery & Traumatology 02/2013; · 0.10 Impact Factor
• Article: Compartment syndrome of the arm caused by transcatheter angiography or angioplasty.

  Shinsuke Omori, Junichi Miyake, Kenichiro Hamada, Norifumi Naka, Nobuhito Araki, Hideki Yoshikawa
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  ABSTRACT: Compartment syndrome of the arm is a rare condition because of the large capacity of the arm compartment. Although several cases of compartment syndrome of the forearm associated with vascular access procedures have been reported, the literature contains few detailed reports of compartment syndrome of the arm caused by transcather angiography or angioplasty. This article presents 4 cases of compartment syndrome of the anterior arm caused by transcatheter angiography or angioplasty; all patients required surgical treatment and anticoagulation therapy. Following urgent fasciotomy and hemostasis, 1 patient experienced recurrent bleeding and another exhibited delayed complex regional pain syndrome of the forearm. The remaining 2 cases had good outcomes.Because all patients had been prescribed various oral anticoagulants, their compartment syndrome was considered a complication of thrombolytic therapy. In addition, because all patients had a history of multiple arterial diseases, atherosclerosis was considered to be severely advanced and the vessels to be easily damaged. Due to the authors' experiences with these 4 cases, they recommend that surgery be performed under general rather than local anesthesia and that the bleeding site be sutured or ligated. Compression of the bleeding point alone could allow heavy bleeding or recurrence of bleeding to occur because of the influence of anticoagulation therapy. Continuous bleeding of the arm may expand into the volar compartment of the forearm, leading to a condition similar to chronic compartment syndrome. Effective hemostasis, in addition to early decompressive fasciotomy, is essential in compartment syndrome caused by the catheter procedure.
  Orthopedics 01/2013; 36(1):e121-5. · 2.66 Impact Factor
• Article: Neoadjuvant and adjuvant chemotherapy with high-dose ifosfamide, doxorubicin, cisplatin and high-dose methotrexate in non-metastatic osteosarcoma of the extremities: a phase II trial in Japan.

  Ikuo Kudawara, Yasuaki Aoki, Takafumi Ueda, Nobuhito Araki, Norifumi Naka, Hirofumi Nakanishi, Akihiko Matsumine, Makoto Ieguchi, Shigeki Mori, Akira Myoui, Shigeyuki Kuratsu, Nobuyuki Hashimoto, Hideki Yoshikawa
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  ABSTRACT: From 1997 to 2003, 40 patients (all <40 years of age) with non-metastatic osteosarcoma of the extremities were treated with OOS-D and definitive surgery. Two cycles of doxorubicin 90 mg/m(2) plus cisplatin 120 mg/m(2) and ifosfamide 15 g/m(2) were given as neoadjuvant chemotherapy, and two cycles of doxorubicin/cisplatin and ifosfamide, and two cycles of high-dose methotrexate (10-12 g/m(2)) were given post-operatively. All patients underwent limb salvage surgeries, and 66% showed good response to neoadjuvant chemotherapy. With a median follow-up period of 117 months, 31 of the evaluable 40 patients were continuously disease-free, 7 were currently alive with no evidence of disease, and 2 died of disease. There was no local recurrence. The 5-year event-free and overall survival rates were 83 and 98%, respectively. The 10-year event-free and overall survival rates were 80 and 95%, respectively. The major form of toxicity was haematological one.
  Journal of chemotherapy (Florence, Italy) 01/2013; 25(1):41-8. · 1.08 Impact Factor
• Article: Repair of meniscal lesions using a scaffold-free tissue-engineered construct derived from allogenic synovial MSCs in a miniature swine model.

  Yu Moriguchi, Kosuke Tateishi, Wataru Ando, Kazunori Shimomura, Yasukazu Yonetani, Yoshinari Tanaka, Keisuke Kita, David A Hart, Alberto Gobbi, Konsei Shino, Hideki Yoshikawa, Norimasa Nakamura
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  ABSTRACT: The menisci of the knee are fibro-cartilaginous tissues and play important roles in the joint, and the loss of the meniscus predisposes the knee to degenerative changes. However, the menisci have limited healing potential due to the paucity of vascularity. The purpose of the present study was to test the feasibility of a scaffold-free tissue-engineered construct (TEC) derived from synovial mesenchymal stem cells (MSCs) to repair incurable meniscal lesions. Porcine synovial MSCs were cultured in monolayers at high density in the presence of ascorbic acid followed by the suspension culture to develop a three-dimensional cell/matrix construct (TEC). A 4-mm cylindrical defect was created bilaterally in the medial meniscus of skeletally mature miniature pigs. The defects were implanted with an allogenic TEC or were left empty. After 6 months, the TEC-treated defects were consistently repaired by a fibro-cartilaginous tissue with good tissue integration to the adjacent host meniscal tissue, while the untreated were either partially or not repaired. The ratio of Safranin O positive area within the central body of the meniscus adjacent to the original defect was significantly higher in the TEC-treated group than in the control group. Moreover, TEC treatment significantly reduced the size and severity of post-traumatic chondral lesions on the tibial plateau. These results suggest that the TEC could be a promising stem cell-based implant to repair meniscal lesions with preventive effects from meniscal body degeneration and the development of post-traumatic arthritis.
  Biomaterials 12/2012; · 7.40 Impact Factor
• Article: Immediate Postoperative Anterior Knee Stability: Double- Versus Triple-Bundle Anterior Cruciate Ligament Reconstructions.

  Tatsuo Mae, Konsei Shino, Norinao Matsumoto, Kenji Yoneda, Hideki Yoshikawa, Ken Nakata
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  ABSTRACT: PURPOSE: The purpose of this study was to compare the triple-bundle (TB) anterior cruciate ligament (ACL) reconstruction with the double-bundle (DB) ACL reconstruction in immediate postoperative anterior knee stability. METHODS: This study involved 133 patients who had undergone the anatomic ACL reconstruction with autogenous hamstring tendon unilaterally. Then 83 patients (mean age, 28.8 years) underwent the DB between November 2004 and December 2005, and 50 patients (mean age, 29.6 years) underwent the TB ACL reconstruction between January and December 2006. The 2 femoral tunnels were created in the ideal ACL attachment area, whereas 2 tibial tunnels for the DB and 3 tunnels for the TB were created in the ACL footprint. The 2 doubled tendon grafts were fixed with EndoButton-CL (Smith & Nephew Endoscopy, Andover, MA) on the femur. The grafts were fixed to the tibia using a Double Spike Plate and a screw under the total initial tension of 20 N at 20° of flexion, after meticulous in situ pretensioning using a tensioning boot. Then immediate postoperative anterior knee laxity in response to 89 N of anterior load was measured by one experienced examiner (T.M.) with the KT-2000 Knee Arthrometer (MEDmedtric, San Diego, CA) under general anesthesia at 30° of knee flexion with muscle relaxants. RESULTS: The measured anterior laxity was 3.4 ± 1.2 mm in the DB and 2.5 ± 0.7 mm in the TB ACL reconstruction, a statistically significant difference. The side-to-side difference of the laxity was -3.2 ± 1.6 mm in the DB and -4.2 ± 2.0 mm in the TB, again a significant difference. CONCLUSIONS: TB ACL reconstruction resulted in better immediate postoperative anterior knee stability than DB ACL reconstruction under 89 N of anterior tibial load (P = .031).
  Arthroscopy The Journal of Arthroscopic and Related Surgery 12/2012; · 3.02 Impact Factor
• Article: Design and optimization of the oriented groove on the hip implant surface to promote bone microstructure integrity.

  Yoshihiro Noyama, Takayoshi Nakano, Takuya Ishimoto, Takashi Sakai, Hideki Yoshikawa
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  ABSTRACT: We proposed a novel surface modification for an artificial hip joint stem from the viewpoint of maintenance and establishment of appropriate bone function and microstructure, represented by the preferred alignment of biological apatite (BAp) and collagen (Col). Oriented grooves were introduced into the proximal medial region of the femoral stem to control the principal stress applied to the bone inside the grooves, which is a dominant factor contributing to the promotion of Col/BAp alignment. The groove angle and the stem material were optimized based on the stress inside the grooves through a finite element analysis (FEA). Only the groove oriented proximally by 60° from the normal direction of the stem surface generated the healthy maximum principal stress distribution. The magnitude of the maximum principal stress inside of the groove decreased with increasing the stem Young's modulus, while the direction of the stress did not largely changed. An in vivo implantation experiment showed that this groove was effective in inducing the new bone with preferential Col/BAp alignment along the groove depth direction which corresponded to the direction of maximum principal stress inside the groove. The anisotropic principal stress distribution and the oriented microstructure inside the groove are similar to those found in the femoral trabeculae; therefore, the creation of the oriented groove is a potent surface modification for optimizing implant design for a long-term fixation.
  Bone 11/2012; · 4.02 Impact Factor
• Article: Vitamin K2 administration is associated with decreased disease activity in patients with rheumatoid arthritis.

  Kosuke Ebina, Kenrin Shi, Makoto Hirao, Shoichi Kaneshiro, Tokimitsu Morimoto, Kota Koizumi, Hideki Yoshikawa, Jun Hashimoto
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  ABSTRACT: OBJECTIVES: Vitamin K2 (VitK2) is reported to induce not only bone mineralization of human osteoblasts and apoptosis of osteoclasts, but also apoptosis of rheumatoid arthritis (RA) synovial cells, while its clinical effect on disease activity of RA remains unknown. METHODS: 158 female RA patients (mean age 62.5 years) who had not been treated with warfarin, biologics, or teriparatide were enrolled in this study. VitK2 (45 mg/day) was administered in 70 patients with a serum undercarboxylated osteocalcin level of >4.5 ng/ml or with decreased bone mineral density in spite of the treatment with other anti-osteoporosis medications, regardless of RA disease activity. A longitudinal study was conducted in 52 patients who were additionally treated with VitK2 without changing their other medications for three months. RESULTS: In the cross-sectional study, as compared to the VitK2-naïve group (n = 88), the VitK2-treated group (n = 70) showed lower serum CRP (1.7 ± 0.2 vs. 0.5 ± 0.1 mg/dl; P < 0.001), MMP-3 (220.4 ± 21.9 vs. 118.0 ± 14.4 ng/ml; P < 0.001), and DAS28-CRP (2.9 ± 0.1 vs. 2.4 ± 0.1; P < 0.05). In the longitudinal study, patients who were additionally treated with VitK2 showed significant decreases in serum CRP (1.1 ± 0.2 to 0.6 ± 0.2 mg/dl; P < 0.001), MMP-3 (160.1 ± 25.6 to 125.0 ± 17.8 ng/ml; P < 0.05), and DAS28-CRP (3.1 ± 0.2 to 2.4 ± 0.1; P < 0.001). CONCLUSIONS: VitK2 may have the potential to improve disease activity besides osteoporosis in RA.
  Modern Rheumatology 11/2012; · 1.58 Impact Factor
• Article: Histological characteristics of the human femoral head in patients with femoral neck fracture.

  Takashi Sakai, Daiki Iwana, Nobuo Nakamura, Takashi Nishii, Masaki Takao, Tetsu Watanabe, Hideki Yoshikawa, Nobuhiko Sugano
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  ABSTRACT: The reparative reaction including angiogenesis and osteogenesis in human bone after an ischemic event remains unknown. To investigate the reparative reaction in human bone, the distribution of tartrate resistant acid phosphatase (TRAP)-positive cells and the expressions of hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), and CD31 were observed around the fracture site in 101 hips in 100 patients with femoral neck fracture. These 17 men and 83 women had a mean age of 80 years (range, 58-97 years). Of the hips, 17 were Garden stage 3, and 84 were Garden stage 4. The mean duration from fracture to surgery was 6.3 days (range, 1-14 days). Hematoxylin-eosin staining, TRAP staining, and immunohistochemistry using anti-HIF-1α, anti-VEGF anti-FGF-2, and anti-CD31 antibodies were performed for the coronal section of the retrieved whole femoral heads. TRAP-positive cells were detected near the trabecular bone around the fracture site in ten hips (10 %). HIF-1α expression was detected in 41 hips (41 %), mainly in the endothelial cells of the vessels. VEGF showed diffuse cytoplasmic staining of the mononuclear cells in the edematous area in 39 hips (39 %) while FGF-2 was detected in the cytoplasm of mononuclear cells in the bone marrow in 82 hips (82 %). CD31 was expressed in the bone marrow vessels in 35 hips (35 %). There were significant differences in HIF-1α expression relative to the duration between the fracture and the surgery, and in CD31 expression relative to Garden stage. HIF-1α expression was detected around the fracture site in the early period after fracture and CD31 expression was detected more frequently in Garden 3 hips while VEGF and FGF-2 expressions were detected regardless of Garden classification.
  Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 10/2012; · 2.49 Impact Factor
• Article: In vivo kinematics of high-flex mobile-bearing total knee arthroplasty, with a new post-cam design, in deep knee bending motion.

  Masahiro Kurita, Tetsuya Tomita, Takaharu Yamazaki, Masakazu Fujii, Kazuma Futai, Norimasa Shimizu, Hideki Yoshikawa, Kazuomi Sugamoto
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  ABSTRACT: PURPOSE: The objective of this study was to evaluate the in vivo knee kinematics to assess the available functional motion of the characteristic mobile-bearing prosthesis design and to examine whether the artificial joint would work in vivo according to its design concept. METHODS: We studied 14 knees (11 patients) implanted with the Vanguard RP Hi-Flex prosthesis. This prosthesis has a highly original form of post-cam called a PS saddle design with high compatibility, and with a rotating plate mobile-bearing mechanism. The cylinder-type post-cam is designed to enable contact in early flexion ranges, and to prevent paradoxical anterior femoral component movement. Each patient performed weight-bearing deep knee bending under fluoroscopic surveillance. Motion between each component including the polyethylene insert was analyzed using the 2D/3D registration technique. RESULTS: The mean range of motion was 122.0°. The mean femoral component rotation for the tibial tray was 5.0°. No paradoxical anterior movement of the nearest point was confirmed between the femoral component and the tibial tray in the early flexion ranges. Initial contact of the post-cam was confirmed at a knee flexion angle of 33.8°. Subsequently, the wide contact of the post-cam was maintained until flexion reached 120° in all knees, but disengagement of the post-cam was observed in two knees when flexion was ≥130°. CONCLUSIONS: The results of this study demonstrated that the prosthesis design generally works in vivo as intended by its design concept. The present kinematic data may provide useful information for improvement of high-flex type prostheses.
  International Orthopaedics 10/2012; · 2.03 Impact Factor
• Article: Dynamic analysis of lung metastasis by mouse osteosarcoma LM8: VEGF is a candidate for anti-metastasis therapy.

  Takaaki Tanaka, Yoshihiro Yui, Norifumi Naka, Toru Wakamatsu, Kiyoko Yoshioka, Nobuhito Araki, Hideki Yoshikawa, Kazuyuki Itoh
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  ABSTRACT: Osteosarcoma (OS) is the most common malignant bone tumor and the prognosis depends on pulmonary metastases, which arise from multi-step progression of malignant tumors. We herein aimed to clarify the critical step of pulmonary metastasis using the syngeneic mouse spontaneous highly metastatic OS LM8 and parental Dunn cell lines, to identify new candidate molecules to suppress pulmonary metastasis. We first investigated the chronological detection of circulating tumor cells (CTCs) from mice with either cell line. LM8 CTCs appeared faster, at a higher rate and with a greater number compared to Dunn CTCs. Cultured cells from CTCs of LM8 showed higher proliferative ability than cells from the primary site in suspension culture, which mimicked the environment of the bloodstream for CTCs. The proliferative ability of LM8 cells was also higher than that of Dunn cells in 3D collagen culture with low stiffness (-150 Pa; close to conditions in the lung). We next focused on the extravasation step. LM8 showed higher migration ability compared to Dunn with transendothelial migration assay. We also found a disruption in endothelial barrier function throughout co-culture with LM8 using time-lapse imaging. In addition, LM8 secreted high levels of vascular endothelial growth factor (VEGF), while VEGF signal inhibition with a small molecule tyrosine kinase inhibitor (pazopanib) decreased disruption of the vascular barrier and transendothelial migration of LM8. Finally, daily oral administration of pazopanib reduced the rate and size of pulmonary metastasis in vivo. Collectively, these results show anti-VEGF therapy as a candidate for pulmonary metastasis of OS.
  Clinical and Experimental Metastasis 10/2012; · 3.52 Impact Factor
• Article: Computer-assisted corrective osteotomy for malunited diaphyseal forearm fractures.

  Junichi Miyake, Tsuyoshi Murase, Kunihiro Oka, Hisao Moritomo, Kazuomi Sugamoto, Hideki Yoshikawa
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  ABSTRACT: Corrective osteotomy for malunited diaphyseal forearm fractures remains a challenging procedure. We developed a computer-assisted system for corrective surgery, including a three-dimensional simulation program and a custom-made osteotomy template, and investigated the results of corrective surgery for malunited diaphyseal forearm fractures with use of this technology. Twenty patients (fifteen male patients and five female patients) with malunited diaphyseal forearm fractures were managed with three-dimensional corrective osteotomy with a custom-made osteotomy template based on computer simulation. We performed osteotomy of both radius and ulna in fourteen patients and osteotomy of the radius alone in six patients. The median age at the time of surgery was eighteen years (range, eleven to forty-three years). The median duration between the time of injury and the time of surgery was thirty-three months (range, five to 384 months). The minimum duration of follow-up was twenty-four months (median, twenty-nine months; range, twenty-four to forty-eight months). To evaluate the results, we compared preoperative and postoperative data from radiographs, forearm motion, grip strength, and pain. The average radiographic deformity angle preoperatively was 21° (range, 12° to 35°) compared with the normal arm; the radiographic deformity angle was improved to 1° (range, 0° to 4°) postoperatively. The distal radioulnar joints of both sides were symmetric on postoperative radiographs regarding the relative lengths of the radius and ulna. In eighteen patients who had a restricted range of forearm motion preoperatively, the mean arc of forearm motion improved from 76° (range, 25° to 160°) preoperatively to 152° (range, 80° to 180°) postoperatively (p < 0.01). However, forearm supination was still restricted by ≥70° in three patients who had been younger than ten years old at the time of the initial injury and who had long-standing malunion for ninety-six months or longer. Painful recurrent dislocation of the distal ulna or radial head resolved or decreased in five patients. Average grip strength improved from 82% to 94% compared with that of the contralateral, normal side. Computer-assisted osteotomy can provide excellent radiographic and clinical outcome for the treatment of malunited diaphyseal forearm fractures. Satisfactory restoration of forearm motion can be achieved even in relatively long-standing cases in adults. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
  The Journal of Bone and Joint Surgery 10/2012; 94(20):e1501-11. · 3.27 Impact Factor
• Article: Constrained Total Hip Megaprosthesis for Primary Periacetabular Tumors.

  Takafumi Ueda, Shigeki Kakunaga, Satoshi Takenaka, Nobuhito Araki, Hideki Yoshikawa
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  ABSTRACT: BACKGROUND: Limb-salvage reconstruction for periacetabular malignant tumors is one of the most challenging problems in orthopaedic oncology. Reconstructive options include resection arthroplasty, endoprosthesis, allograft, recycled autobone graft, arthrodesis, and pseudarthrosis. However, no standard procedure exists because of rarity and clinical variability of the disease. We previously developed a megaprosthetic system with a constrained total hip mechanism (C-THA). QUESTIONS/PURPOSES: We evaluated (1) survival of patients and C-THA; (2) postoperative function; and (3) complications. METHODS: We retrospectively reviewed 25 patients with primary periacetabular tumors treated using C-THA between 1985 and 2009. There were 18 male and seven female patients with a median age of 44 years (range, 16-72 years). They included 11 chondrosarcomas, eight osteosarcomas, two giant cell tumors of bone (one locally aggressive benign, one malignant), and others in four. Surgical margin was wide in 18 patients, marginal in five, and intralesional in two. The minimum postoperative followup for survivors was 32 months (median, 163 months; range, 32-285 months). RESULTS: The 10-year overall survival rate of all patients was 47%. C-THA implants survived in 19 of 25 patients at last followup. Twenty-one patients acquired ambulatory activity. There were seven local recurrences, resulting in hemipelvectomy in one patient. Postoperative complications included deep infection in eight of the 25 patients, dislocation in four, and aseptic loosening in two, necessitating five revision surgeries and three implant removals. CONCLUSIONS: Our observations suggest C-THA using an acetabular reconstruction cup is a useful reconstructive option after resection of periacetabular malignant tumors despite frequent postoperative complications. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
  Clinical Orthopaedics and Related Research 09/2012; · 2.53 Impact Factor
• Article: Metaphyseal Bone Collapse Mimicking Slipped Capital Femoral Epiphysis in Severe Renal Osteodystrophy.

  Masaki Takao, Jun Hashimoto, Takashi Sakai, Takashi Nishii, Nobuhiko Sugano, Hideki Yoshikawa
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  ABSTRACT: Context:Slipped capital femoral epiphysis is a well-recognized skeletal complication of renal osteodystrophy in adolescence, which is distinct from idiopathic slipped capital femoral epiphysis in its etiology.Objective:We report a case of severe mixed-type renal osteodystrophy with metaphyseal bone collapse that mimicked slipped capital femoral epiphyses.Methods:Case history, laboratory and radiological evaluation, and bone biopsies are discussed.Results:A 14-yr-old girl presented with left hip pain showing bilateral metaphyseal bone collapse accompanied with posterior-inferior displacement of capital femoral epiphyses after 2.5 yr of GH treatment. Blood chemistry, showing high levels of alkaline phosphatase and PTH, and a transiliac bone biopsy, indicating severe osteomalacia with osteitis fibrosa, along with serial computed tomography images of the hips from the presymptomatic stage, led to accurate diagnosis and successful treatment by administration of high-dose vitamin D.Conclusion:This case emphasizes the importance of controlling hyperparathyroidism well in children with chronic renal insufficiency, particularly at adolescence before initiating GH treatment. When children with renal insufficiency present with displacement of capital femoral epiphysis, it is necessary to evaluate the serum levels of alkaline phosphatase and PTH and metaphyseal bone quality below the physis.
  The Journal of clinical endocrinology and metabolism 09/2012; · 6.50 Impact Factor