Masatoshi Komatsu
Shinshu University
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Publication
Featured researches published by Masatoshi Komatsu.
Journal of Bone and Joint Surgery-british Volume | 2015
H. Yamazaki; Shigeharu Uchiyama; Masatoshi Komatsu; S. Hashimoto; Yasuhiro Kobayashi; T. Sakurai; Hiroyuki Kato
There is no consensus on the benefit of arthroscopically assisted reduction of the articular surface combined with fixation using a volar locking plate for the treatment of intra-articular distal radial fractures. In this study we compared the functional and radiographic outcomes of fluoroscopically and arthroscopically guided reduction of these fractures. Between February 2009 and May 2013, 74 patients with unilateral unstable intra-articular distal radial fractures were randomised equally into the two groups for treatment. The mean age of these 74 patients was 64 years (24 to 92). We compared functional outcomes including active range of movement of the wrist, grip strength and Disabilities of the Arm, Shoulder, and Hand scores at six and 48 weeks; and radiographic outcomes that included gap, step, radial inclination, volar angulation and ulnar variance. There were no significant differences between the techniques with regard to functional outcomes or radiographic parameters. The mean gap and step in the fluoroscopic and arthroscopic groups were comparable at 0.9 mm (standard deviation (SD) 0.7) and 0.7 mm (SD 0.7) and 0.6 mm (SD 0.6) and 0.4 mm (SD 0.5), respectively; p = 0.18 and p = 0.35). Arthroscopic reduction conferred no advantage over conventional fluoroscopic guidance in achieving anatomical reduction of intra-articular distal radial fractures when using a volar locking plate.
Journal of Hand Surgery (European Volume) | 2015
Hiroshi Yamazaki; Shigeharu Uchiyama; Masatoshi Komatsu; Shun Hashimoto; Hiroyuki Kato
PURPOSE To identify risk factors for tendon attrition after volar locking plate fixation of distal radius fractures. METHODS We prospectively assessed attrition of the flexor pollicis longus tendon at volar plate removal in 127 hands in 126 patients. We also evaluated preoperative lateral wrist radiographs, sonographs, and crepitus with flexor pollicis longus tendon motion and compared the demographic and radiographic characteristics of patients with and without tendon attrition. Multivariate logistic regression analysis was employed to identify the factors independently associated with tendon attrition. RESULTS We found 12 cases of tendon attrition (10%) and 1 that presented with tendon rupture in our cohort. Crepitus was recognized in 14 patients (11%): 6 cases (50%) were among the 12 hands in 12 patients with tendon attrition whereas 8 (7%) were detected in the remaining 114 hands in 113 patients. Logistic regression examination revealed that audible crepitus and volar placement of the plate in lateral radiographs were independent predictors of tendon attrition. CONCLUSIONS Crepitus and volar placement of hardware in lateral radiographs were independent risk factors for flexor tendon attrition after volar plating for distal radius fracture. These results may facilitate surgical decisions regarding early plate removal to prevent possible tendon rupture. TYPE OF STUDY/LEVEL OF EVIDENCE Diagnostic II.
Therapeutics and Clinical Risk Management | 2015
Yukio Nakamura; Mikio Kamimura; Shota Ikegami; Keijiro Mukaiyama; Masatoshi Komatsu; Shigeharu Uchiyama; Hiroyuki Kato
The syndrome of pregnancy- and lactation-associated osteoporosis is a rare disorder whose precise etiology and treatment are largely unknown. We herein report two such cases occurring in the early postpartum period that led to multiple fragility compression fractures. Combination therapy of vitamin D and vitamin K enabled a marked gradual increase in bone mineral density.
Journal of Orthopaedic Science | 2015
Masatoshi Komatsu; Yukio Nakamura; Masaaki Maruyama; Kazutoshi Abe; Ramida Watanapokasin; Hiroyuki Kato
ObjectiveOsteoarthritis (OA) and rheumatoid arthritis (RA) are widespread disabling joint disorders that are considered to be polygenic in nature. This study investigated the spatial expression patterns of all six known human CCN genes using end-stage OA and RA joint samples.DesignWe performed in situ hybridization and histological analysis to investigate the spatial expression patterns of human CCN genes using joint tissues obtained during total knee and hip joint replacement procedures on patients with advanced OA or RA. Normal joint tissues taken while performing bipolar hip replacement surgeries were used as controls.ResultsAll CCN genes were expressed at higher levels in OA and RA synovial samples as compared with normal controls. Whereas CCN3 and CCN6 were undetectable in control, OA, and RA cartilage, CCN1, CCN2, CCN4, and CCN5 were expressed to a greater extent in OA and RA knee cartilage.ConclusionsOur results indicate an involvement of several CCN genes in the pathophysiology of OA and RA.
Scientific Reports | 2016
Mikio Kamimura; Yukio Nakamura; Noriyuki Sugino; Shigeharu Uchiyama; Masatoshi Komatsu; Shota Ikegami; Hiroyuki Kato; Akira Taguchi
Some vertebral fractures come to clinical attention but most do not. This cross-sectional survey aimed to clarify the associations of self-reported height loss and kyphosis with vertebral fractures. We enrolled 407 women aged 60–92 years who visited our orthopaedic clinic between June and August 2014 in our study. Inclusion criteria were lateral radiography followed by completion of a structured questionnaire in this study. The primary outcome was vertebral fracture diagnosed on lateral radiography and graded using a semiquantitative grading method, from SQ0 (normal) to SQ3 (severe). Self-reported kyphosis was defined as none, mild to moderate, severe. Self-reported height loss was defined as <4 cm or ≥4 cm. Number of SQ1 fracture was associated only with kyphosis. Self-reported severe kyphosis was significantly associated with increased numbers of ≥SQ2 vertebral fractures (p = 0.007). Height loss ≥4 cm was significantly associated with increased ≥SQ2 grade fractures (p < 0.001). Odds ratios (ORs) for fractures associated with mild-to-moderate and severe kyphosis were 2.1 [95% confidence interval 1.4 to 3.3) and 4.2 (1.8 to 9.5), respectively. OR for fractures associated with height loss ≥4 cm was 2.3 (1.4 to 3.7). Self-reported kyphosis may be useful for identifying Japanese women aged ≥60 years who have undetected vertebral fractures.
Scientific Reports | 2016
Yukio Nakamura; Shigeharu Uchiyama; Mikio Kamimura; Masatoshi Komatsu; Shota Ikegami; Hiroyuki Kato
The etiology of ankle osteoarthritis (OA) is largely unknown. We analyzed 24 ankle OA of 21 patients diagnosed by plain radiographs using magnetic resonance imaging (MRI). Ankle joint pain disappeared in 22 out of 24 joints by conservative treatment. MRI bone signal changes in and around the ankle joints were observed in 22 of 24 joints. Bone signal changes along the joint line were seen in 10 of 11 joints as a Kellgren-Lawrence (KL) grade of II to IV. Such signal changes were witnessed in only 4 of 13 joints with KL grade 0 or I. In the talocrural joint, bone alterations occurred in both tibia and talus bones through the joint line in cases of KL grade III or IV, while focal bone alterations were present in the talus only in KL grade I or II cases. Sixteen of 24 joints exhibited intraosseous bone signal changes, which tended to correspond to joint pain of any ankle OA stage. Our results suggest that bone alterations around the ankle joint might be one of the etiologies of OA and associated with ankle joint pain.
Osteoporosis and sarcopenia | 2016
Mikio Kamimura; Yukio Nakamura; Shota Ikegami; Masatoshi Komatsu; Shigeharu Uchiyama; Hiroyuki Kato
As a bisphosphonate, minodronate (MIN) is one of the strongest inhibitors of bone resorption. However, there have been no reports directly comparing the antiresorptive effects of monthly MIN with those of monthly risedronate (RIS). We enrolled 30 cases of osteoporosis (OP; 16 in the MIN group [mean age: 68.2 years] and 14 in the RIS group [mean age: 68.1 years]) to investigate the early effects of treatment by monthly MIN or RIS over a 4-month period using bone turnover marker values. Only female patients were enrolled to avoid gender bias. Urinary cross-linked N-telopeptide of type I collagen (NTX) before treatment and at 1, 2, and 4 months of therapy, as well as serum bone alkaline phosphatase and alkaline phosphatase before treatment and at 4 months afterwards, were evaluated. All bone turnover marker values were significantly decreased at 4 months in both groups. The changes in urinary NTX at the study end point for RIS and MIN were −30.1% and −63.1%, respectively. From 2 months of treatment, the antiresorptive effects on urinary NTX by MIN were significantly higher than those by RIS, indicating that MIN more immediately and strongly inhibited bone absorption. Thus, monthly MIN seems to suppress bone resorption faster and more strongly than RIS in OP treatment.
American Journal of Case Reports | 2014
Masatoshi Komatsu; Yukio Nakamura; Mikio Kamimura; Shigeharu Uchiyama; Keijiro Mukaiyama; Shota Ikegami; Hiroyuki Kato
Patient: Male, 83 Final Diagnosis: Osteoarthritis Symptoms: Knee joint pain Medication: — Clinical Procedure: Resting Specialty: Orthopedics and Traumatology Objective: Challenging differential diagnosis Background: Osteoarthritis (OA) is the leading cause of musculoskeletal pain and functional disability worldwide. However, the etiology of this condition is still largely unknown. Case Report: We report the clinical course of an elderly man with knee OA. Conclusions: Plain radiographs and MRI examinations performed during follow-up suggested that the pathophysiology of the patient’s knee OA and joint pain may have been primarily due to bone alterations.
Tohoku Journal of Experimental Medicine | 2017
Yukio Nakamura; Shigeharu Uchiyama; Mikio Kamimura; Shota Ikegami; Masatoshi Komatsu; Hiroyuki Kato
Osteoporosis is characterized by the systemic impairment of bone mass, strength, and microarchitecture, leading to an increased risk of fragility fracture. Bisphosphonates (BPs) are the first-line drugs for osteoporosis. Vitamin D is considered to be essential for osteoporotic treatment. However, long-term effects of BPs on the serum levels of 25-hydroxyvitamin D3 (25(OH)D3) are unknown. Accordingly, in this retrospective study, we collected clinical data of 41 post-menopausal Japanese women with osteoporosis treated with BP for over 3 years, without vitamin D supplementation. We measured lumbar and femoral neck bone mineral density (BMD) and serum levels of bone specific alkaline phosphatase (BAP) as a bone formation marker, and tartrate-resistant acid phosphatase (TRACP)-5b as a bone resorption marker, before and after the 3-year treatment. Serum 25(OH)D3, 1,25(OH)2D3, and whole parathyroid hormone (PTH) were also measured. Notably, no fracture occurred during the treatment. Compared with baseline values, 25(OH)D3 levels were significantly increased from 21.6 to 26.4 ng/mL (P = 0.006), despite no vitamin D supplementation. 1,25(OH)2D3 and whole PTH levels tended to be decreased from 62.6 to 57.8 pg/mL and 27.3 to 25.1 pg/mL, respectively. Both bone formation and resorption markers were significantly suppressed (P < 0.01). Both lumbar BMD (7.3% increase) and femoral neck BMD (4.1% increase) were significantly improved (P < 0.0001) after 3 years of the treatment. Thus, even without vitamin D supplementation, serum 25(OH)D3 levels were significantly increased after 3-year BP therapy. These results suggest that vitamin D supplementation might not be required in the long-term BP therapy for osteoporosis.
International Journal of Rheumatic Diseases | 2017
Masatoshi Komatsu; Mikio Kamimura; Yukio Nakamura; Keijiro Mukaiyama; Shota Ikegami; Masanori Hayashi; Shigeharu Uchiyama; Hiroyuki Kato
Osteoarthritis (OA) is the most common skeletal disease worldwide. Although thumb carpametacarpal joint (CMJ) OA is also frequently encountered, the etiologies remain largely unknown.