Papers - Iwamoto, Takuji

A role for the aryl hydrocarbon receptor and the dioxin TCDD in rheumatoid arthritis

Kobayashi, S., Okamoto, H., Iwamoto, T., Toyama, Y., Tomatsu, T., Yamanaka, H. and Momohara, S.

Rheumatology (Oxford) 47 ( 9 ) 1317 - 22 2008.09

ISSN  1462-0332

　View Summary

OBJECTIVE: Environmental factors are involved in RA pathogenesis and epidemiological studies have suggested that smoking is an environmental risk factor for RA. The 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is one of the major toxic components in cigarettes. To clarify the biological effects of smoking in RA, we investigated the role of TCDD in RA pathogenesis. METHODS: Human synovial tissue was obtained from RA and OA patients and aryl hydrocarbon receptor (AhR) expression in these tissues was evaluated using immunohistochemistry and real-time PCR. Expression of various cytokines was measured by real-time PCR following stimulation of RA synoviocytes with different concentrations of TCDD. To study the role of AhR, we treated RA synoviocytes with alpha-naphthoflavone, a known AhR antagonist. To evaluate which signal transduction pathways were stimulated by the TCDD-AhR interaction, we used inhibitors of nuclear factor-kappaB (NF-kappaB) and extra-cellular stimulus-activated kinase (ERK). RESULTS: Higher AhR mRNA and protein levels were observed in RA synovial tissue than in OA tissue. TCDD up-regulated the expression of IL-1beta, IL-6 and IL-8 through binding to AhR, and this effect was transmitted via the NF-kappaB and ERK signalling cascades. AhR expression in synovial cells was up-regulated by TNF-alpha. CONCLUSION: TNF-alpha activates AhR expression in RA synovial tissue, and that cigarette smoking and exposure to TCDD enhances RA inflammatory processes. TCDD induces inflammatory cytokines via its association with AhR, resulting in stimulation of the NF-kappaB and ERK signalling cascades. Thus TCDD exposure, such as smoking exacerbates RA pathophysiology.

• Access to Document (DOI)

Molecular aspects of rheumatoid arthritis: chemokines in the joints of patients

Iwamoto, T., Okamoto, H., Toyama, Y. and Momohara, S.

FEBS J 275 ( 18 ) 4448 - 55 2008.09

ISSN  1742-464X

　View Summary

Rheumatoid arthritis (RA) is a chronic symmetric polyarticular joint disease that primarily affects the small joints of the hands and feet. The inflammatory process is characterized by infiltration of inflammatory cells into the joints, leading to proliferation of synoviocytes and destruction of cartilage and bone. In RA synovial tissue, the infiltrating cells such as macrophages, T cells, B cells and dendritic cells play important role in the pathogenesis of RA. Migration of leukocytes into the synovium is a regulated multi-step process, involving interactions between leukocytes and endothelial cells, cellular adhesion molecules, as well as chemokines and chemokine receptors. Chemokines are small, chemoattractant cytokines which play key roles in the accumulation of inflammatory cells at the site of inflammation. It is known that synovial tissue and synovial fluid from RA patients contain increased concentrations of several chemokines, such as monocyte chemoattractant protein-4 (MCP-4)/CCL13, pulmonary and activation-regulated chemokine (PARC)/CCL18, monokine induced by interferon-gamma (Mig)/CXCL9, stromal cell-derived factor 1 (SDF-1)/CXCL12, monocyte chemotactic protein 1 (MCP-1)/CCL2, macrophage inflammatory protein 1alpha (MIP-1alpha)/CCL3, and Fractalkine/CXC3CL1. Therefore, chemokines and chemokine-receptors are considered to be important molecules in RA pathology.

• Access to Document (DOI)

CTLA-4 CT60 polymorphism is not an independent genetic risk marker of rheumatoid arthritis in a Japanese population

Tsukahara, S., Iwamoto, T., Ikari, K., Inoue, E., Tomatsu, T., Hara, M., Yamanaka, H., Kamatani, N. and Momohara, S.

Ann Rheum Dis 67 ( 3 ) 428 - 9 2008.03

ISSN  1468-2060

• Access to Document (DOI)

A role of monocyte chemoattractant protein-4 (MCP-4)/CCL13 from chondrocytes in rheumatoid arthritis

Iwamoto, T., Okamoto, H., Kobayashi, S., Ikari, K., Toyama, Y., Tomatsu, T., Kamatani, N. and Momohara, S.

FEBS J 274 ( 18 ) 4904 - 12 2007.09

ISSN  1742-464X

　View Summary

We studied the role of monocyte chemoattractant (MCP)-4/CCL13 in the pathogenesis of rheumatoid arthritis (RA). MCP-4 was highly expressed in cartilage from RA patients. Interferon-gamma significantly stimulated MCP-4/CCL13 production in human chondrocytes, and this effect was enhanced in combination with interleukin-1beta or tumor necrosis factor-alpha. MCP-4/CCL13 induces the phosphorylation of extracellular signal-regulated kinase in fibroblast-like synoviocytes and activates cell proliferation, and PD98059 completely inhibits these effects. These data suggest that interferon-gamma in combination with interleukin-1beta/tumor necrosis factor-alpha activates the production of MCP-4/CCL13 from chondrocytes in RA joints, and that secreted MCP-4/CCL13 enhances fibroblast-like synoviocyte proliferation by activating the extracellular signal-regulated kinase mitogen-activated protein kinase cascade.

• Access to Document (DOI)

High CCL18/PARC expression in articular cartilage and synovial tissue of patients with rheumatoid arthritis

Momohara, S., Okamoto, H., Iwamoto, T., Mizumura, T., Ikari, K., Kawaguchi, Y., Takeuchi, M., Kamatani, N. and Tomatsu, T.

J Rheumatol 34 ( 2 ) 266 - 71 2007.02

ISSN  0315-162X

　View Summary

OBJECTIVE: We studied the role of CCL18/pulmonary and activation-regulated chemokine (PARC) in rheumatoid arthritis (RA). METHODS: Human cartilage tissues and synovial membranes were obtained from patients with RA and with osteoarthritis (OA). Sera samples were obtained from RA patients, OA patients, healthy controls, and patients with flu, and synovial fluid (SF) from patients with RA and OA. Real-time PCR was performed with RNA from cartilage samples. Immunohistochemical analysis of CCL18/PARC was done with RA and OA cartilage and synovial tissue. Levels of CCL18/PARC in serum and SF were evaluated by ELISA. RESULTS: CCL18/PARC mRNA was expressed at significantly higher levels in RA cartilage than in OA (p = 0.0001) and control (p < 0.0001) samples. CCL18/PARC mRNA expression was much higher in RA synovial membrane than OA samples (p = 0.0001). All RA cartilage and synovial tissue samples exhibited medium to strong staining for CCL18/PARC. Serum levels of CCL18/PARC were higher in RA patients (156.21 +/- 125.73 ng/ml, n = 71) than in OA patients (64.54 +/- 40.90 ng/ml, n = 12) and controls (28.04 +/- 10.96 ng/ml, n = 20). Levels of CCL18/PARC in RA SF (275.20 +/- 228.16 ng/ml, n = 15) were higher than in OA (33.13 +/- 14.84 ng/ml, n = 6; p = 0.0198). CCL18/PARC levels correlated significantly with rheumatoid factor levels (r = 0.431, p = 0.0040), but not with matrix metalloproteinase-3, erythrocyte sedimentation rate, and C-reactive protein. CONCLUSION: CCL18/PARC was highly expressed in RA articular cartilage and synovial tissue compared with OA samples. Our data indicated that CCL18/PARC levels are not related to the conditions of generalized inflammation, but are related to the pathogenesis of RA.

• Access to Document (DOI)

Failure to confirm association between PDCD1 polymorphisms and rheumatoid arthritis in a Japanese population

Iwamoto, T., Ikari, K., Inoue, E., Toyama, Y., Hara, M., Yamanaka, H., Tomatsu, T., Momohara, S. and Kamatani, N.

J Hum Genet 52 ( 6 ) 557 - 60 2007

ISSN  1434-5161

　View Summary

Programmed cell death 1 (PDCD1) is a necessary negative regulator to maintain peripheral tolerance and is a key molecule in the development of autoimmune diseases. Although PDCD1 gene polymorphisms and haplotypes were reported to be associated with rheumatoid arthritis (RA), replication studies later on showed conflicting results. Here, we analyzed the association of PDCD1 with RA using a large series of Japanese RA patients and population-based controls. DNA samples were obtained from 1,504 RA patients and 449 sex-matched controls. All samples were genotyped for three SNPs on PDCD1 (PD-1.1, PD-1.3 and PD-1.5) using the TaqMan fluorogenic 5' nuclease assay. Chi-square testing was performed for a case-control study, and the PENHAPLO program was used for haplotype estimation. We could not observe any significant association of PD-1.1 or PD-1.5 polymorphisms between RA. PD-1.3, which was reported to be involved in susceptibility to RA in patients of European descent, was non-polymorphic in the Japanese population. We conclude that polymorphisms in the PDCD1 gene analyzed here are not associated with RA in a Japanese population.

• Access to Document (DOI)

The serum concentration of infliximab in cases of autologous blood donation for patients with rheumatoid arthritis

Mochizuki, T., Momohara, S., Ikari, K., Okamoto, H., Kobayashi, S., Tsukahara, S., Iwamoto, T., Kawamura, K., Saito, S. and Tomatsu, T.

Mod Rheumatol 17 ( 1 ) 24 - 7 2007

ISSN  1439-7595

　View Summary

Our aim was to determine whether the use of infliximab for rheumatoid arthritis (RA) patients is associated with an increased rate of postoperative complications. In this study we evaluated the serum concentration of infliximab to study the influence of autologous blood donation (AB donation) in patients who were administered infliximab and underwent total knee replacement (TKR). We examined five RA patients. Infliximab combined with methotrexate was administered at 3 mg/kg every 8 weeks for all patients. We carried out the TKR operation in the middle of the 8-week interval in which infliximab was administered. The AB donation consisted of 400 ml pooled AB drawn at one point 2 weeks following the final administration of infliximab. Serum infliximab levels were measured using an enzyme-linked immunosorbent assay. Mean serum infliximab levels were 5.46 +/- 5.62 microg/ml 2 weeks after the final administration of infliximab, 2.02 +/- 1.66 microg/ml just before the operation, and 1.48 +/- 1.31 microg/ml 1 day post operation. Moreover, the mean serum level in an autologous blood bag sampled just before AB donation was 5.02 +/- 4.79 microg/ml. This study indicated the serum level of infliximab in the stored blood remained at almost the same level as the collected autologous blood. However, even after autotransfusion those levels were decreased compared with levels measured just before the operation. Therefore, we conclude that there is little influence of AB donation on the risks of infliximab.

• Access to Document (DOI)

舟状骨骨折に対する小皮切による骨接合術の治療成績

吉川泰弘, 岩本卓士, 竹田誠, 石井聖佳 and 池田崇

骨折 28 ( 4 ) 659 - 661 2006.12

ISSN  0287-2285

　View Summary

舟状骨骨折29例に小皮切による骨接合術を行い、治療成績を検討した。骨折型(Herbert分類)は、A2型:10例、B1型:4例、B2型:5例、B3型:2例、B4型:1例、C型:7例であった。全例で骨癒合が得られ、A・B型22例中20例(91%)は8週以内の骨癒合であった。臨床評価(Cooneyの評価基準)はexcellent:24例、good:4例、fair:1例であった。固定材料にはHeadless bone screw、double threaded screw、Acutrak screw、Herbert screwを用いたが、骨癒合や臨床成績に明らかな違いはなかった。この方法は、小侵襲で良好な骨癒合が得られる有用な方法である。A型骨折への適応もあるが、B型骨折は手術操作における整復確認に、C型骨折は適応に注意する必要があると考えられた。

特発性前骨間・後骨間神経麻痺の保存的・外科的治療

岩本卓士, 松村崇史, 越智健介, 高木岳彦 and 別所祐貴

日本手の外科学会雑誌 23 ( 2 ) 71 - 74 2006.10

ISSN  0910-5700

　View Summary

2000～2004年に受信した非外傷性の前骨間神経麻痺(AIN麻痺)6例(男1例、女5例)、後骨間神経麻痺(PIN麻痺)3例(男1例、女2例、発症時年齢12～66歳)の計9例を対象に検討した。発症後3ヵ月で手術を施行したPIN麻痺の1例を除き、原則として6～8ヵ月間の保存治療法を行い、回復傾向を認めない症例に対し神経内神経剥離術を行った。保存療法で回復を認めたものが6例(AIN麻痺4例、PIN麻痺2例)、手術を行った症例が3例(AIN麻痺2例、PIN麻痺1例)で、観察期間は5～31ヵ月の保存療法例で10日間～10ヵ月、手術療法例では8～16ヵ月であった。発症後6ヵ月以内に保存的で回復を認めたのは6例中2例であった。手術療法3例全てに外的圧迫因子のない部位に神経束の砂時計様くびれを認め、くびれ部の中枢から末梢にゼリー様浮腫を呈していた。さらに2例で斜走する線維状索状物(oblique fibrous band)が神経束を直接圧迫しており、これを切離することで除圧が得られ麻痺の回復に影響を与える一因子と考えられた。

Production of monocyte chemoattractant protein-4 (MCP-4)/CCL13 by interferon-γ-activated human chondrocytes and its role in rheumatoid arthritis.

Iwamoto, T; Okamoto, H; Ikari, K; Iikuni, N; Toyama, Y; Tomatsu, T; Kamatani, N; Momohara, S

ARTHRITIS AND RHEUMATISM 54 ( 9 ) S88 - S88 2006.09

ISSN  0004-3591

Association between PADI4 and rheumatoid arthritis: a meta-analysis

Iwamoto, T., Ikari, K., Nakamura, T., Kuwahara, M., Toyama, Y., Tomatsu, T., Momohara, S. and Kamatani, N.

Rheumatology (Oxford) 45 ( 7 ) 804 - 7 2006.07

ISSN  1462-0324

　View Summary

OBJECTIVE: Polymorphisms and haplotypes of the peptidylarginine deiminase type 4 gene (PADI4) have been reported to be associated with rheumatoid arthritis (RA) in a Japanese population. However, subsequent replication studies showed conflicting results. The aim of this study was to determine whether meta-analysis would prove the existence of the association. METHODS: PubMed was searched using the term 'PADI4' for articles from the publication of the first study to December 2005. Replication studies that tested the association between PADI4 and RA were reviewed for meta-analysis. The Breslow-Day test for homogeneity across the studies was calculated. The Mantel-Haenszel procedure was used to pool odds ratios (OR) with 95% confidence intervals (CI) to evaluate the association. RESULTS: Six replication studies, one from Japan and five from Europe and North America, fulfilled the selection criteria for inclusion in the meta-analysis. Homogeneity was confirmed across the replication studies. The common OR was 1.14 (95% CI = 1.07-1.21) for allelic distribution. The association was confirmed when only five replication studies in the European descent populations were combined (P = 0.0096, common OR = 1.10). CONCLUSIONS: Our meta-analysis showed a positive association between PADI4 and RA not only in the Japanese population but also in populations of European descent.

• Access to Document (DOI)

Monocyte chemoattractant protein-4 (MCP-4)/CCL13 is highly expressed in cartilage from patients with rheumatoid arthritis

Iwamoto, T., Okamoto, H., Iikuni, N., Takeuchi, M., Toyama, Y., Tomatsu, T., Kamatani, N. and Momohara, S.

Rheumatology (Oxford) 45 ( 4 ) 421 - 4 2006.04

ISSN  1462-0324

　View Summary

OBJECTIVES: To study the role of monocyte chemoattractant protein-4 (MCP-4)/CCL13 in the pathogenesis of rheumatoid arthritis (RA), we analysed the expression of MCP-4/CCL13 in chondrocytes, synovial fluid and serum from patients with RA and investigated the effect of MCP-4/CCL13 on the proliferation of synovial cells. METHODS: Human articular cartilage specimens were obtained from joints from RA and osteoarthritis (OA) patients and normal joints (controls). Transcript levels of MCP-4 in cartilage were determined by real-time polymerase chain reaction. Protein levels were measured by enzyme-linked immunoassay. Cultured fibroblast-like synoviocytes (FLS) were treated with various concentrations of recombinant MCP-4/CCL13 protein, and cell proliferation was evaluated with a viability assay. RESULTS: The gene expression of MCP-4 was significantly higher in cartilage from RA patients than in that from OA patients (P = 0.00902) and in normal cartilage (P = 0.00902). The concentration of MCP-4/CCL13 protein in serum from RA patients (mean 94.7 +/- 37.6 pg/ml) was significantly higher than in serum from OA patients (mean 49.2 +/- 31.2 pg/ml, P = 0.0051) and controls (mean 32.6 +/- 23.9 pg/ml, P = 0.0001). The concentration of MCP-4/CCL13 protein in synovial fluid from RA patients (mean 247.2 +/- 161.2 pg/ml) was also significantly higher than in that from OA patients (mean 29.6 +/- 50.5 pg/ml, P = 0.000019). Moreover, MCP-4/CCL13 enhanced the proliferation of FLS in a dose-dependent manner. CONCLUSIONS: MCP-4/CCL13 is highly expressed in RA joints at the mRNA and protein levels. Our results suggest that MCP-4/CCL13 is secreted from chondrocytes and activates the proliferation of rheumatoid synovial cells, thereby leading to joint destruction in RA.

• Access to Document (DOI)

Raised monocyte chemotactic protein-1 (MCP-1)/CCL2 in cerebrospinal fluid of patients with neuropsychiatric lupus

Iikuni, N., Okamoto, H., Yoshio, T., Sato, E., Kamitsuji, S., Iwamoto, T., Momohara, S., Taniguchi, A., Yamanaka, H., Minota, S. and Kamatani, N.

Ann Rheum Dis 65 ( 2 ) 253 - 6 2006.02

ISSN  0003-4967

　View Summary

BACKGROUND: An imbalance in cytokine homoeostasis is thought to have a key role in the neuropsychiatric syndromes of systemic lupus erythematosus (NPSLE), and recently, a role for chemokines has been noted. OBJECTIVE: To compare concentrations of monocyte chemotactic protein-1 (MCP-1)/CCL2 in cerebral spinal fluid (CSF) of patients with SLE, and with and without neuropsychiatric symptoms. METHODS: CSF was obtained from 185 patients with SLE: 96 with NPSLE and 89 patients with SLE without neuropsychiatric symptoms (non-NPSLE patients). MCP-1/CCL2 concentrations were measured with an ELISA. RESULTS: The average concentration of CSF MCP-1/CCL2 in patients with NPSLE was 1959 pg/ml, and in non-NPSLE patients 712 pg/ml. The average MCP-1/CCL2 concentration was significantly higher in the NPSLE group than in the non-NPSLE group (p<0.001). In one representative patient with NPSLE, MCP-1/CCL2 levels in the CSF decreased in parallel with a decline in neuropsychiatric symptoms. CONCLUSIONS: CSF MCP-1/CCL2 levels are higher in patients with NPSLE than in non-NPSLE patients. MCP-1/CCL2 may have an important role in the expression of NPSLE. These results indicate that CSF MCP-1/CCL2 reflects an inflammatory activity in the brain, suggesting that it might be used as a diagnostic tool and a monitor for therapeutic responses in patients with NPSLE.

• Access to Document (DOI)

Acute destruction of the hip joints and rapid resorption of femoral head in patients with rheumatoid arthritis

Yoshino, K., Momohara, S., Ikari, K., Kawamura, K., Mochizuki, T., Iwamoto, T., Niki, Y., Saitou, S. and Tomatsu, T.

Mod Rheumatol 16 ( 6 ) 395 - 400 2006

ISSN  1439-7595

　View Summary

We report three rheumatoid arthritis (RA) cases with acute destruction of hip joint and rapid resorption of femoral head. The condition occurred in less than 6 months and closely resembled rapid destructive coxarthrosis. All three patients were postmenopausal women with active RA who had been taking steroids. Two of the patients were taking prednisolone (PSL) of over 20 mg as maximum dose per day, and all patients were resistant to disease-modifying anti-rheumatic drugs (DMARDs). Other than the problems of their hip joints, one had a giant bursitis around the pathological side of the hip joint, another had multiple rheumatoid nodules and skin infarction, and the other suffered from insufficiency fracture of the contralateral femoral subcapital lesion. As a result, all of them had total hip arthroplasty. We recommend taking repetitive radiographs for RA patients with continuing severe hip pain.

• Access to Document (DOI)

橈骨遠位端骨折に合併した尺骨遠位部骨折の治療

吉川泰弘, 岩本卓士, 石井聖佳 and 池田崇

日本手の外科学会雑誌 22 ( 4 ) 441 - 445 2005.11

ISSN  0910-5700

　View Summary

橈骨遠位端骨折に合併した尺骨遠位部骨折24例(男4例・女20例,平均72歳)の成績を報告した.骨折型はBiyani分類1型8例,2型4例,3型5例,4型7例で,橈骨遠位端骨折はA2が1例,A3が6例,C1が6例,C2が7例,C3が4例であった.尺骨遠位部骨折の治療は保存療法2例,ピンニング2例,髄内釘3例,tension band wiring 8例,low-profile plate(LPP)9例で,橈骨遠位端骨折にはピンニング2例,プレート固定12例,創外固定10例を行った.術後4～28ヵ月で,骨幹端部は全例骨癒合したが,茎状突起では4例が偽関節となった.Fernandezの評価法による臨床成績はexcellent 8例,good 10例,fair 4例,poor 2例で,合併症はCRPSを1例に認めた.Biyani分類4型はfair以下が多く,治療法別ではLPPが比較的良好であった.成績不良の原因としては,粉砕の程度が強い骨折や開放骨折,茎状突起基部の偽関節,橈骨遠位端粉砕骨折の合併,尺骨のmalalignmentが考えられた

Monocyte chemoattractant protein-4/CCL13 is highly expressed in cartilage from patients with rheumatoid arthritis.

Iwamoto, T; Okamoto, H; Iikuni, N; Toyama, Y; Tomatsu, T; Kamatani, N; Momohara, S

ARTHRITIS AND RHEUMATISM 52 ( 9 ) S473 - S473 2005.09

ISSN  0004-3591

The possibility of peroxisome proliferator-activated receptor-alpha ligand for the treatment of osteoarthritis and rheumatoid arthritis.

Iwamoto, T; Okamoto, H; Iikuni, N; Toyama, Y; Tomatsu, T; Kamatani, N; Momohara, S

ARTHRITIS AND RHEUMATISM 52 ( 9 ) S243 - S244 2005.09

ISSN  0004-3591

逆行性浅腓腹動脈皮弁による下腿皮膚欠損の再建手術

岩本卓士, 吉川泰弘, 竹田誠, 石井聖佳 and 松林経世

整形外科 56 ( 4 ) 393 - 396 2005.04

ISSN  0030-5901

　View Summary

逆行性浅腓腹動脈皮弁(sural flap)による下腿・足部の皮膚軟部組織欠損部の再建症例5例(男性4例,女性1例)を対象に,治療成績について検討した.なお,皮弁採取部は4例で一期的に縫縮し,皮弁の大きさが6×9であった1例は二期的な遊離植皮を行った.皮弁は全例で一期的に生着を認め,治療成績は良好であった.以上より,sural flapによる再建は,安全で容易に行うことができ有用である

肘関節伸展制限を生じた小児上腕骨小頭骨折の1例

吉川泰弘 and 岩本卓士

日本肘関節学会雑誌 11 ( 1 ) 105 - 106 2004.12

ISSN  1349-7324

　View Summary

9歳女児.足を滑らせ転倒受傷した.近医で左肘関節後方脱臼の診断で徒手整復を受け,1週間の外固定後に可動域訓練を開始した.肘関節の可動域が改善しないため,受傷後8週で受診した.MRIでは正面像で外顆骨端核の外側遠位に骨折がみられ,側面像で小頭骨端核の後下方に骨性突出が存在し,基部は小頭骨端核と骨癒合し,その先端は橈骨頭と衝突していた.また,骨性突出に連続してすぐ後方には骨欠損部を認めた.上腕骨小頭後下方部分の関節内骨折の診断で,受傷後3ヵ月半で手術を行った.術後1週より可動域訓練を開始し,術後3週でROMは良好であった.術後3年の現在,X線上外顆中央部の骨性隆起は消失し,肘関節に不安定性,疼痛はなく,ROMも伸展+10°,屈曲145°で左右差はない

橈骨遠位端関節内骨折(AO分類C型)に対するCompack創外固定器による治療

吉川泰弘, 岩本卓士, 森田晃造 and 岩部昌平

日本手の外科学会雑誌 21 ( 4 ) 535 - 539 2004.11

ISSN  0910-5700

　View Summary

橈骨遠位端関節内骨折(AO分類C型)18例18骨に対してnon-bridging型のCompack創外固定器による治療を行った.治療成績はexcellent 12例,good 5例,fair 1例で,合併症はピンの刺激症状が1例,complex regional pain syndrome(CRPS)が1例であった.CRPS例を除いた関節可動域の平均は掌屈52.2°,背屈58.7°,回内78.5°,回外72.9°であった.X線評価ではvolar tilt,radial inclination,ulnar varianceはいずれも術後から調査時まで僅かな矯正損失を認めたが,1mm以内に整復されたstep offは調査時まで良好に保たれていた.粉砕骨変例や骨粗鬆症例に対する整復位保持には,Kirschner綱線固定の併用や人工骨補填材が有効であった.また,5 part以上のC3型粉砕骨折例に対しては,ハープピンとKirschner鋼線により格子状の面を形成して関節面を保持する方法が有効であった