Sakae Tanaka

The University of Tokyo, Tōkyō, Japan

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Publications (231)890.5 Total impact

  • Yusuke Tsuda · Hideo Yasunaga · Hiromasa Horiguchi · Kiyohide Fushimi · Hirotaka Kawano · Sakae Tanaka
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    ABSTRACT: Background: Currently, there are few reports regarding predictors of postoperative complications and short-term mortality after surgery for pathological femur fracture related to bone metastasis. Methods: Using data from the Japanese Diagnosis Procedure Combination Database from 2007 to 2012, we retrospectively identified 1497 patients who underwent internal fixation (n = 1073) or proximal femur resection and endoprosthetic reconstruction of the proximal femur (n = 424) for pathological femur fracture related to bone metastasis. Multivariable logistic regression analysis was performed to examine the relationship of various factors with postoperative complications and 30-day mortality. Results: The overall 30-day mortality after surgery was 2.6 %, and the proportion of postoperative complications was 12.1 %. Multivariable logistic regression analysis showed that postoperative complications overall were significantly associated with older age [odds ratio (OR), 2.15; 95 % confidence interval (CI) 1.23-3.74 for age ≥80 vs. ≤59 years]; lung carcinoma (OR 2.05; 95 % CI 1.47-2.86); esophageal carcinoma (OR 4.41; 95 % CI 1.57-12.43); higher Charlson Comorbidity Index (OR 1.50; 95 % CI 1.03-2.18 for ≥9 vs. 8); and blood transfusion (OR 1.57; 95 % CI 1.14-2.15). Thirty-day mortality also was significantly higher in patients with rapid-growth tumors, visceral metastasis, internal fixation, and no postoperative chemotherapy in the univariate analysis. Conclusions: Older age, type of primary tumor, higher Charlson Comorbidity Index, and blood transfusion were associated with higher morbidity. These findings can provide important information to assess perioperative risk in patients with pathological femur fracture related to bone metastasis.
    Annals of Surgical Oncology 10/2015; DOI:10.1245/s10434-015-4881-9 · 3.93 Impact Factor
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    ABSTRACT: Background: Although a few studies on perioperative stroke following spinal surgery have been reported, differences in the incidence of perioperative stroke among various surgical procedures have not been determined. The purpose of this retrospective analysis was to investigate the incidence of perioperative stroke during hospitalization in patients undergoing elective spinal surgery, and to examine whether the incidence varied according to the surgical procedure. Methods: A retrospective analysis of data from the Diagnosis Procedure Combination database, a nationwide administrative impatient database in Japan, identified 167,106 patients who underwent elective spinal surgery during 2007-2012. Patient information extracted included age, sex, preoperative comorbidity, administration of blood transfusion, length of hospitalization, and type of hospital. Clinical outcomes included perioperative stroke during hospitalization, and in-hospital death. Results: The overall incidence of perioperative stroke was 0.22 % (371/167,106) during hospitalization. A logistic regression model fitted with a generalized estimating equation showed perioperative stroke was associated with advanced age, a history of cardiac disease, an academic institution, and resection of a spinal tumor. Patients who underwent resection of a spinal cord tumor (reference) had a higher risk of stroke compared with those undergoing discectomy (odds ratio (OR), 0.29; 95 % confidence interval (CI), 0.14-0.58; p = 0.001), decompression surgery (OR, 0.44; 95 % CI, 0.26-0.73; p = 0.001), or arthrodesis surgery (OR, 0.55; 95 % CI, 0.34-0.90); p = 0.02). Advanced age (≥80 years; OR, 5.66; 95 % CI, 3.10-10.34; p ≤ 0.001), history of cardiac disease (OR, 1.58; 95 % CI, 1.10-2.26; p = 0.01), diabetes (OR, 1.73; 95 % CI, 1.36-2.20; p ≤ 0.001), hypertension (OR, 1.53; 95 % CI, 1.18-1.98; p = 0.001), cervical spine surgery (OR, 1.44; 95 % CI, 1.09-1.90; p = 0.01), a teaching hospital (OR, 1.36; 95 % CI, 1.01-1.82; p = 0.04), and length of stay (OR, 1.008; 95 % CI, 1.005-1.010; p ≤ 0.001) were also risk factors for perioperative stroke. Conclusions: Perioperative stroke occurred in 0.22 % of patients undergoing spinal surgery. Resection of a spinal cord tumor was associated with increased risk of perioperative stroke as well as advanced age, comorbidities at admission, cervical spine surgery, surgery in a teaching hospital, and length of stay.
    BMC Musculoskeletal Disorders 10/2015; 16(1):276. DOI:10.1186/s12891-015-0743-7 · 1.72 Impact Factor
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    ABSTRACT: Objectives: We investigated the effect of cartilage degeneration on ultrasound speed in human articular cartilage in vitro. Methods: Ultrasound speed was calculated by the time-of-flight method for twenty-two femoral condyle osteochondral blocks obtained from osteoarthritis patients. In parallel, histological evaluation of specimens was performed using the modified Mankin and OARSI scores. Results: The mean ultrasound speed was 1757 ± 109 m/s. Ultrasound speed showed significant negative correlation with OARSI score, and a decreasing tendency with high Mankin scores. Good correlation was found between the optically measured and the calculated cartilage thickness. Conclusion: Our results show that articular cartilage degeneration has relatively little influence on ultrasound speed. In addition, morphological evaluation of articular cartilage using a preset value of ultrasound speed seems to offer relatively accurate results.
    Modern Rheumatology 09/2015; DOI:10.3109/14397595.2015.1097012 · 2.40 Impact Factor
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    ABSTRACT: Idiopathic osteonecrosis of the talus is a rare but severe condition that directly affects the ability to walk and is difficult to treat either conservatively or surgically. We report the case of a 72-year-old female with idiopathic necrosis of the talus treated with total talar replacement surgery. A custom-made aluminum-ceramic total talar prosthesis was prepared using the mirror image of the computed tomography and radiographic data from the contralateral ankle. The talus was exposed and removed using an anterior approach, and the total talar prosthesis was inserted. The prosthesis was placed in a stable position between the tibia, calcaneus, and navicular, with no signs of instability with ankle joint movement. The ankle was immobilized in a short-leg cast for 3 weeks. At the latest follow-up examination, 2 years after surgery, the patient was walking without pain. Examination of the left ankle showed 20° of dorsiflexion and 40° of plantar flexion. The American Orthopaedic Foot and Ankle Society ankle/hindfoot score was 90, which had improved from a preoperative score of 45. Radiographic examination showed that the prosthesis was in a stable position in the ankle mortise, and no degenerative or destructive changes were observed in the surrounding bones. This is the first reported case of total talar replacement with a prosthesis for idiopathic talar necrosis. Although the long-term outcome is still unknown, this procedure could provide a good treatment option for idiopathic necrosis of the talus.
    The Journal of foot and ankle surgery: official publication of the American College of Foot and Ankle Surgeons 09/2015; DOI:10.1053/j.jfas.2015.07.015 · 0.85 Impact Factor
  • Global Spine Journal 09/2015; DOI:10.1055/s-0035-1563725
  • Archives of Orthopaedic and Trauma Surgery 09/2015; DOI:10.1007/s00402-015-2321-8 · 1.60 Impact Factor
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    ABSTRACT: Dumbbell-shaped tumors consisting of 2 different tumors are extremely rare. Herein, the authors present a case of concurrent spinal schwannoma and meningioma mimicking a single cervical dumbbell-shaped tumor. A 64-year-old man presented with a 5-year history of gradually exacerbating left occipital pain without clinical evidence of neurofibromatosis. Magnetic resonance imaging showed an extradural tumor along the left C-2 nerve root with a small intradural component. The tumor was approached via a C-1 hemilaminectomy. The intradural tumor was resected together with the extradural tumor after opening the dura mater. The intradural tumor was attached to the dura mater around the exit point of the C-2 nerve root. Intraoperative biopsy revealed that the extradural tumor was a schwannoma and that the intradural tumor was a meningioma. The dura mater adjacent to the tumor was then coagulated and resected. Postoperative pathological examination confirmed the same diagnoses with no evidence of continuity between the intra- and extradural components. The patient's postoperative clinical course was uneventful. Clinicians should be aware that cervical dumbbell-shaped tumors can consist of 2 different tumors.
    Journal of neurosurgery. Spine 08/2015; DOI:10.3171/2015.3.SPINE141315 · 2.38 Impact Factor
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    ABSTRACT: Rheumatoid arthritis (RA) is an autoimmune destructive arthritis associated with CD4(+) T cell-mediated immunity. Although expanded CD4(+) T cell clones (ECs) has already been confirmed, the detailed characteristics of ECs have not been elucidated in RA. Using combination of a single-cell analysis and next-generation sequencing (NGS) in TCR repertoire analysis, we here revealed the detailed nature of ECs by examining peripheral blood (PB) from 5 RA patients and synovium from 1 RA patient. When we intensively investigated the single-cell transcriptome of the most expanded clones in memory CD4(+) T cells (memory-mECs) in RA-PB, senescence-related transcripts were up-regulated, indicating circulating ECs were constantly stimulated. Tracking of the transcriptome shift within the same memory-mECs between PB and the synovium revealed the augmentations in senescence-related gene expression and the up-regulation of synovium-homing chemokine receptors in the synovium. Our in-depth characterization of ECs in RA successfully demonstrated the presence of the specific immunological selection pressure, which determines the phenotype of ECs. Moreover, transcriptome tracking added novel aspects to the underlying sequential immune processes. Our approach may provide new insights into the pathophysiology of RA.
    Scientific Reports 08/2015; 5:12937. DOI:10.1038/srep12937 · 5.58 Impact Factor
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    ABSTRACT: Although hip osteoarthritis (OA) is a major cause of hip pain and disability in elderly people, few epidemiologic studies have been performed. We investigated the prevalence of radiographic hip OA and its association with hip pain in Japanese men and women using a large-scale population of a nationwide cohort study, Research on Osteoarthritis/osteoporosis Against Disability (ROAD). From the baseline survey of the ROAD study, 2,975 participants (1,043 men and 1,932 women), aged 23-94 years (mean 70.2 years), living in urban, mountainous, and coastal communities were analyzed. The radiographic severity at both hips was determined by the Kellgren/Lawrence (K/L) grading system. Radiographic hip OA was defined as K/L ≥2, and severe radiographic hip OA as K/L ≥3. The crude prevalence of radiographic hip OA was 18.2% and 14.3% in men and women, respectively, that of severe radiographic hip OA was 1.34% and 2.54%, and that of symptomatic K/L ≥2 OA was 0.29% and 0.99%, respectively. The crude prevalence of hip OA, including severe OA, was not age-dependent in men or women. Male sex was a risk factor for radiographic hip OA, whereas female sex was a risk factor for severe radiographic hip OA and hip pain. Compared with K/L = 0/1, hip pain was significantly associated with K/L ≥3, but not with K/L=2. The present cross-sectional study revealed the prevalence of radiographic hip OA and severe hip OA in Japanese men and women. Hip pain was strongly associated with K/L ≥3. Copyright © 2015. Published by Elsevier Ltd.
    Osteoarthritis and Cartilage 08/2015; DOI:10.1016/j.joca.2015.07.017 · 4.17 Impact Factor
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    ABSTRACT: Induced pluripotent stem cells (iPSCs) are a promising cell source for cartilage regenerative medicine. Meanwhile, the risk of tumorigenesis should be considered in the clinical application of human iPSCs (hiPSCs). Here, we report in vitro chondrogenic differentiation of hiPSCs and maturation of the differentiated hiPSCs through transplantation into mouse knee joints. Three hiPSC clones showed efficient chondrogenic differentiation using an established protocol for human embryonic stem cells. The differentiated hiPSCs formed hyaline cartilage tissues at 8 weeks after transplantation into the articular cartilage of NOD/SCID mouse knee joints. Although tumors were not observed during the 8 weeks after transplantation, an immature teratoma had developed in one mouse at 16 weeks. In conclusion, hiPSCs are a potent cell source for regeneration of hyaline articular cartilage. However, the risk of tumorigenesis should be managed for clinical application in the future.
    Biomedical Research 07/2015; 36(3):179-86. DOI:10.2220/biomedres.36.179 · 1.14 Impact Factor
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    ABSTRACT: We investigated the serum levels of the phosphorylated form of the high molecular weight neurofilament subunit (pNF-H) in patients with cervical compressive myelopathy. pNF-H is becoming increasingly recognized as a biomarker for axonal injury, however, it remains unclear whether serum pNF-H is elevated in chronic spinal cord compression. We examined 26 patients who underwent surgery for cervical compressive myelopathy. Peripheral blood samples were obtained both preoperatively and 1week after surgery to evaluate the serum pNF-H levels using an enzyme-linked immunosorbent assay. A history of recent aggravation of myelopathy was also investigated. Of the 26 myelopathy patients, the preoperative serum pNF-H level was negative in 20 patients and moderately elevated in six. Patients who were positive for pNF-H were more likely to have had a recent aggravation of myelopathy compared with the pNF-H negative patients (83 versus 25%; p=0.02). All patients who were positive for pNF-H before surgery remained positive after surgery. Two patients who became positive after surgery demonstrated a neurologic deterioration associated with the surgery. In conclusion, the serum pNF-H level was negative in the majority of patients with cervical compressive myelopathy. Our results suggest that an elevated serum level of pNF-H is associated with an acute worsening of myelopathy and that a positive conversion of pNF-H after surgery is a marker of perioperative neural damage. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Journal of Clinical Neuroscience 07/2015; 22(10). DOI:10.1016/j.jocn.2015.03.047 · 1.38 Impact Factor
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    ABSTRACT: Whiplash-associated disorders (WAD) are the most common injuries that are associated with car collisions in Japan and many Western countries. However, there is no clear evidence regarding the potential risk factors for poor recovery from WAD. Therefore, we used an online survey of the Japanese population to examine the association between potential risk factors and the persistence of symptoms in individuals with WAD. An online survey was completed by 127,956 participants, including 4,164 participants who had been involved in a traffic collision. A random sample of the collision participants (n = 1,698) were provided with a secondary questionnaire. From among the 974 (57.4%) respondents to the secondary questionnaire, we selected 183 cases (intractable neck pain that was treated over a period of 6 months) and 333 controls (minor neck pain that was treated within 3 months). Multivariable logistic regression analysis was used to evaluate the potential risk factors for prolonged treatment of WAD. Female sex, the severity of the collision, poor expectations of recovery, victim mentality, dizziness, numbness or pain in the arms, and lower back pain were associated with a poor recovery from WAD. In the present study, the baseline symptoms (dizziness, numbness or pain in the arms, and lower back pain) had the strongest associations with prolonged treatment for WAD, although the psychological and behavioral factors were also important. These risk factors should be considered when evaluating patients who may have the potential for poor outcomes.
    PLoS ONE 07/2015; 10(7):e0132191. DOI:10.1371/journal.pone.0132191 · 3.23 Impact Factor
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    ABSTRACT: Sterilization using high-energy irradiation is an important aspect of implementing an ultra-high molecular weight polyethylene acetabular liner in total hip arthroplasty (THA). In this study, we evaluate the effects of extra irradiations such as gamma-ray or plasma irradiation during sterilization of the poly(2-methacryloyloxyethyl phosphorylcholine [MPC]) (PMPC) surface and cross-linked polyethylene (CLPE) substrate of a PMPC-grafted CLPE acetabular liner. The PMPC-grafted surface yielded high wettability and low friction properties regardless of the extra irradiations as compared with untreated CLPE. During a hip simulator test, wear resistance of the PMPC-grafted CLPE liner was maintained after extra irradiation, which is due to the high wettability characteristics of the PMPC surface. In particular, the PMPC-grafted CLPE liner treated with plasma irradiation showed greater wettability and wear resistance than that with gamma-ray irradiation. However, we could not clearly observe the changes in chemical properties and morphology of the PMPC surface after both extra irradiations. The physical and mechanical properties attributed to CLPE substrate performance were also unchanged. In contrast, PMPC-grafted CLPE treated with plasma irradiation showed improved oxidation resistance as compared to that treated with gamma-ray irradiation after accelerated aging. Thus, we conclude that PMPC-grafted CLPE with plasma irradiation has promise as a lifelong solution for bearing in THA. This article is protected by copyright. All rights reserved. © 2015 Wiley Periodicals, Inc.
    Journal of Biomedical Materials Research Part A 07/2015; DOI:10.1002/jbm.a.35538 · 3.37 Impact Factor
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    ABSTRACT: Total en bloc spondylectomy (TES) is accompanied by preoperative embolization of segmental arteries, which is limited to three consecutive levels to avoid the risk of spinal cord ischemia. We retrospectively examined the efficacy and safety of repeated TES with embolization of more than three levels of segmental arteries. Seven patients underwent TES twice for spinal metastases at different levels. Every patient underwent embolization of the bilateral segmental arteries before each surgery. We assessed the total number of segmental arteries embolized, the existence of Adamkiewicz arteries during the embolization procedure, intraoperative blood loss, and the motor function of the lower limbs, using the American Spinal Injury Association (ASIA) motor score. No patient experienced any motor deficit after embolization. During the embolization procedure, an Adamkiewicz artery was depicted in five patients, which precluded embolization at that level. The median number of segmental arteries embolized in total was 9 (9-11). Intraoperative blood loss (median, IQR) was 480 (420-630) ml during the first surgery and 520 (280-600) ml during the second surgery. The ASIA motor scores (median, IQR) were as follows; 100 (98-100) (first admission), 100 (100-100) (first discharge), 100 (98-100) (second admission), and 97 (94-100) (second discharge). No patients had developed statistically significant neurological deterioration, and there had been no local recurrence after a median follow-up of 17.8 months (range 1-51 months). Repeated TES procedures can be performed safely even if more than three levels of segmental arteries are embolized.
    European Spine Journal 07/2015; DOI:10.1007/s00586-015-4091-y · 2.07 Impact Factor
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    ABSTRACT: We examined the individual and combined effects of teriparatide and anti-RANKL (receptor activator of nuclear factor κB ligand) monoclonal antibody in ovariectomized mice. Three-month-old female C57BL/6 mice were ovariectomized (OVX) or sham operated. Four weeks after OVX, they were assigned to 3 different groups to receive anti-RANKL monoclonal antibody (Ab) alone (5 mg/kg single injection at 4 weeks after OVX, Ab group), teriparatide alone (80 μg/kg daily injection for 4 weeks from 4 weeks after OVX, PTH group), or mAb plus teriparatide (Ab + PTH group). Mice were sacrificed 8 weeks after OVX. Bone mineral density (BMD) was measured at the femur and lumbar spine. Hind limbs were subjected to histological and histomorphometric analysis. Serum osteocalcin and CTX-I levels were measured to investigate the bone turnover. Compared with Ab group, Ab + PTH group showed a significant increase in BMD at distal femur and femoral shaft. Cortical bone volume was significantly increased in PTH and Ab + PTH groups compared with Ab group. Bone turnover in Ab + PTH group was suppressed to the same degree as in Ab group. The number of TRAP-positive multinucleated cells was markedly reduced in Ab and Ab + PTH groups. These results suggest that combined treatment of teriparatide with anti-RANKL antibody has additive effects on BMD in OVX mice compared with individual treatment.
    06/2015; 2. DOI:10.1016/j.bonr.2014.12.002
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    ABSTRACT: We aimed to clarify the association between new indices in a locomotive syndrome risk test and decline in mobility. In the third survey of the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study, data on the indices were obtained from 1575 subjects (513 men, 1062 women) of the 1721 participants in mountainous and coastal areas. As outcome measures for decline in mobility, we used the five-times-sit-to-stand test (FTSST) and walking speed with cutoff values of 12 s and 0.8 m/s, respectively. We first estimated the prevalence of the indices in locomotive syndrome risk test stage 1, including two-step test score <1.3, difficulty with one-leg standing from a 40-cm-high seat in the stand-up test, and 25-question GLFS score ≥7, which were found to be 57.4, 40.6, and 22.6 %, respectively. Next, we investigated the prevalence of the indices in locomotive syndrome risk test stage 2, including two-step test score <1.1, difficulty with standing from a 20-cm-high seat using both legs in the stand-up test, and 25-question GLFS score ≥16, which were found to be 21.1, 7.9, and 10.6 %, respectively. Logistic regression analysis using slow FTSST time or slow walking speed as the objective factor, and presence or absence of indices as the independent factor, after adjusting for confounders, showed all three indices in both stages 1 and 2 were significantly and independently associated with immobility. Finally, we clarified the risk of immobility according to an increasing number of indices in both stages 1 and 2 and found that the odds ratio for both slow FTSST time and slow walking speed increased exponentially. We found that the three indices independently predicted immobility and that accumulation of indices increased the risk of immobility exponentially.
    Journal of Orthopaedic Science 06/2015; DOI:10.1007/s00776-015-0741-5 · 0.94 Impact Factor
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    ABSTRACT: Total en bloc spondylectomy (TES) is a surgical procedure performed to achieve complete resection of an aggressive benign spinal tumor or a malignant spinal tumor. When reconstructing the spine after resection, we have been using liquid nitrogen-frozen resected spine bearing tumor as a bone graft, expecting an immunological response to tumor-specific antigen(s). The purpose of this article is to report a successful treatment case of lung adenocarcinoma metastasis with TES and this cryotherapy. A 59-year-old male presented with rapid progression of neurological deterioration of the lower limbs due to a spinal metastasis from T8 to T10. The primary lung adenocarcinoma had already been excised under thoracoscopy. The patient underwent TES with reconstruction using frozen tumor-bearing vertebra for the bone graft. One month after surgery, a new nodule appeared at the right middle lobe of the lung. However, we carried out no biopsy of the newly emerged nodule and the patient received no adjuvant chemotherapy or radiotherapy. Six months after surgery, the tumor vanished. No local recurrence or metastasis of the tumor has been observed until now. TES with a liquid nitrogen-frozen tumor specimen could be a promising therapeutic option for cancer patients with spine metastasis.
    European Spine Journal 06/2015; DOI:10.1007/s00586-015-4077-9 · 2.07 Impact Factor
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    ABSTRACT: In the construction of artificial hip joint replacements, the surface and substrate of a cross-linked polyethylene (CLPE) liner are designed to achieve high wear resistance and prevent infection by bacteria. In this study, we fabricated a highly hydrophilic and antibiofouling poly(2-methacryloyloxyethyl phosphorylcholine [MPC]) (PMPC)-graft layer on the vitamin E-blended CLPE (HD-CLPE(VE)) surface. The 100-nm-thick, smooth, and electrically neutral PMPC layer was successfully fabricated on the HD-CLPE(VE) surface using photoinduced graft polymerization. The PMPC-grafted HD-CLPE(VE) was found to prevent bacterial adherence and biofilm formation on the surface because of the formation of a highly hydrophilic polyzwitterionic layer on the surface of HD-CLPE(VE), which can serve as an extremely efficient antibiofouling layer. The number of bacterial adhered on the PMPC-grafted HD-CLPE(VE) surface was reduced by 100-fold or more by PMPC grafting, regardless of the biofilm-production characteristics of the strains. In contrast, vitamin E blending did not affect bacterial adhesion. Moreover, the number of planktonic bacteria did not differ significantly, regardless of PMPC grafting and vitamin E blending. In conclusion, the PMPC-grafted HD-CLPE(VE) provided bacteriostatic effects associated with smooth, highly hydrophilic surfaces with a neutral electrostatic charge owing to the zwitterionic structure of the MPC unit. Thus, this modification may prove useful for the production of artificial hip joint replacement materials. Copyright © 2015. Published by Elsevier Ltd.
    Acta biomaterialia 06/2015; 24. DOI:10.1016/j.actbio.2015.05.034 · 6.03 Impact Factor
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    ABSTRACT: Surface modification by grafting of biocompatible phospholipid polymer onto the surface of artificial joint material has been proposed to reduce the risk of aseptic loosening and improve the durability. Poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-grafted cross-linked polyethylene (CLPE) has shown promising results for reducing wear of CLPE. The main lubrication mechanism for the PMPC layer is considered to be the hydration lubrication. In this study, the lubrication properties of PMPC-grafted CLPE were evaluated in reciprocating friction test with rehydration process by unloading in various lubricants. The start-up friction of PMPC-grafted CLPE was reduced, and the damage of PMPC layer was suppressed by rehydration in water or hyaluronic acid solutions. In contrast, the start-up friction of PMPC-grafted CLPE increased in fetal bovine serum solution, and the damage for PMPC layer was quite noticeable. Interestingly, the start-up friction of PMPC-grafted CLPE was reduced in fetal bovine serum solution containing hyaluronic acid, and the damage of the PMPC layer was suppressed. These results indicate that the rehydration by unloading and hyaluronic acid are elemental in maximizing the lubrication effect of hydrated PMPC layer. © IMechE 2015.
    06/2015; 229(7). DOI:10.1177/0954411915588969

Publication Stats

7k Citations
890.50 Total Impact Points


  • 1997–2015
    • The University of Tokyo
      • • Department of Orthopaedic Surgery and Spinal Surgery
      • • Division of Sensory and Motor System Medicine
      • • School of Medicine
      Tōkyō, Japan
    • Tokyo Metropolitan Institute of Medical Science
      Edo, Tōkyō, Japan
  • 2009–2014
    • Tokyo Medical University
      • Department of Orthopedic Surgery
      Edo, Tōkyō, Japan
  • 2004–2014
    • Sagamihara National Hospital
      Йокосука, Kanagawa, Japan
  • 1992–2009
    • Showa University
      • • Department of Biochemistry
      • • School of Dentistry
      Shinagawa, Tōkyō, Japan
  • 2005
    • National Hospital Organization Sagamihara Hospital
      Sagamihara, Kanagawa, Japan