Tsutomu Kobayashi

Efficacy of the clinical use of iguratimod therapy in patients with rheumatoid arthritis

Abstract Objective. Iguratimod (IGU) is a new synthetic disease-modifying antirheumatic drug intended to treat patients with rheumatoid arthritis (RA). We conducted a 24-week study on the efficacy of IGU in RA patients with daily clinical use. Methods. Forty-one patients were enrolled in this study, and the improvement in RA was evaluated every 4 weeks during the 24 weeks. Results. The patients global assessment of the disease activity with a scale (Pt VAS) was significantly decreased beginning at week 4. The disease activity score (DAS) 28-erythrocyte sedimentation rate, DAS28-C-reactive protein (CRP), simplified disease activity index and clinical disease activity index all significantly decreased at week 24. The matrix metalloproteinase-3 level was significantly decreased by the combination treatment with methotrexate at week 24. According to a logistic regression analysis, the factor which was most associated with the achievement of low disease activity (DAS28-CRP < 2.7) at week 24 was the DAS28-CRP at week 0. Conclusions. IGU had significant clinical effects on the RA patients within 24 weeks. IGU might therefore represent a new practical choice to treat RA patients.

Prospective multifactorial analysis of preseason risk factors for shoulder and elbow injuries in high school baseball pitchers.

PurposeTo prospectively identify preseason physical factors for shoulder and elbow injuries during the season in high school baseball pitchers.MethodsThe study included 105 high school baseball pitchers [median age 16 (15–17)xa0years]. The range of motion of the shoulder (90° abducted external and internal rotation) and elbow (extension/flexion), shoulder muscle strength (abduction and prone internal and external rotation), shoulder and elbow laxity, horizontal flexion, and scapular dyskinesis were assessed. After the season, the participants completed questionnaires regarding shoulder and/or elbow injuries, with injury defined as an inability to play for ≥1xa0week due to elbow/shoulder problems. The results of two groups (injured and noninjured) were compared using t tests and Chi-square analyses. Stepwise forward logistic regression models were developed to identify risk factors.ResultsTwenty-one injuries were observed. In univariate analysis, 90° abducted internal rotation and total arc of the dominant shoulder and the ratio of prone external rotation in the dominant to nondominant sides in the injured group were significantly less than those in the noninjured group (Pxa0=xa00.02, 0.04, and 0.01, respectively). In logistic regression analysis, 90° abducted internal rotation in the dominant shoulder and prone external rotation ratio were significantly associated with injuries (Pxa0=xa00.02 and 0.03, respectively).ConclusionA low prone external rotation ratio and decreased 90° abducted internal rotation in the dominant shoulder in the preseason were significant risk factors for shoulder and elbow injuries in high school baseball pitchers. The results may contribute to reduce the incidence of these injuries.Level of evidenceII.

[18F]fluorodeoxyglucose uptake as a predictor of large joint destruction in patients with rheumatoid arthritis.

The present retrospective study investigated the relationship between [18F]fluorodeoxyglucose–positron emission tomography (FDG-PET) findings and subsequent progression of joint destruction on plain X-ray. Nineteen rheumatoid arthritis (RA) patients (59 joints) who underwent FDG-PET and whose joints could be evaluated on plain X-ray 5xa0years later were included in this retrospective investigation. The relationship between the standardized uptake value (SUV) on FDG-PET and Larsen grade progression on plain X-ray was investigated for each joint. Factors related to progression of joint destruction were also investigated. Joints with advanced joint destruction (Larsen grades IV and V) on X-ray imaging at the time of FDG-PET were excluded. On initial plain X-ray images taken at the time of FDG-PET, a significant correlation was observed between the initial SUV of each joint and the progression of joint destruction 5xa0years later (Rxa0=xa00.47, Pxa0<xa00.01). Significant correlations between the SUV and progression of joint destruction were observed in both load-bearing (Rxa0=xa00.52, Pxa0<xa00.01) and non-load-bearing joints (Rxa0=xa00.52, Pxa0<xa00.01). On logistic regression analysis, higher SUV and lower prednisolone dose were associated with greater risk of progressive joint destruction (Pxa0<xa00.05). On receiver operating characteristics curve analysis, the optimum threshold for identifying preceding joint destruction was an SUVmean of 1.33. In RA joints, FDG uptake was seen mostly by inflammatory cells; therefore, FDG uptake reflected joint inflammation. Additionally, the activity seen on FDG-PET might be associated with future radiographic changes in RA patients.

The impact of faulty posture on rotator cuff tears with and without symptoms

HYPOTHESISnWe hypothesized that the prevalence of rotator cuff tears would be higher among individuals with poor posture, regardless of the presence of symptoms.nnnMETHODSnThe study initially comprised 525 residents of a mountain village who participated in an annual health check. Participants completed a background questionnaire, and physical examinations were performed to evaluate shoulder function. Ultrasonographic examinations were also performed to identify rotator cuff tears, and participants were grouped according to the presence or absence of tears. Posture was classified by 2 observers into 4 types according to the classification of Kendall, as follows: ideal alignment, kyphotic-lordotic posture, flat-back posture, and sway-back posture. Univariate analyses were performed to compare differences in background characteristics between groups, then multivariate analysis was performed to identify those factors associated with rotator cuff tears.nnnRESULTSnFinal analysis was performed for 379 participants (135 men, 244 women; mean age, 62.0 years; range, 31-94 years) showing the same posture classification from both observers. Of these, 93 (24.5%) showed rotator cuff tear in one shoulder and 45 (11.9%) showed tears in both. Prevalence of rotator cuff tears was 2.9% with ideal alignment, 65.8% with kyphotic-lordotic posture, 54.3% with flat-back posture, and 48.9% with sway-back posture. Logistic regression analysis identified increased age, abnormal posture, and past pain as factors associated with rotator cuff tears.nnnCONCLUSIONSnPostural abnormality represented an independent predictor of both symptomatic and asymptomatic rotator cuff tears. These results may help define preventive measures for rotator cuff tears and in design ing rehabilitation therapies for shoulder disease.

Characteristics of neck and shoulder pain in the Japanese general population

BackgroundNeck and shoulder pain (NSP) is very common in the general population. However, little is known about the epidemiology of this condition. The purpose of this study was to investigate the characteristics and the factors associated with NSP and to reveal its effect on health-related quality of life (HRQOL).MethodsMedical checkups were conducted among the residents of a mountain village where agroforestry and tourism are the main industries. The participants comprised 863 residents, including 308 males and 555 females. NSP was defined as the symptoms of muscle tension, stiffness, pressure or dull pain extending from the neck to the scapular arch. The participants completed a questionnaire including information on the presence of NSP, age, gender, musculoskeletal pain at other anatomical sites and medical complications. The NSP-associated factors obtained by the questionnaire were investigated using univariate and multivariate analyses. The EuroQol (i.e., EQ-5D and EQ-VAS) was also assessed.ResultsThe prevalence of NSP was 48.3xa0%, and NSP was more common in females than males. The prevalence was higher in the generation from 20 to 50xa0years of age and decreased with age. NSP was associated with pain in the upper extremities and lower EuroQol scores, but not with pain in the lower extremities or medical complications. A multivariate logistic regression analysis showed that female gender and pain in the upper extremities were independently associated with NSP.ConclusionsWe used a general concept of NSP, which allowed us to collect the unified data about this condition among the participants. NSP was a prevalent health problem that led to deterioration of the HRQOL in the general population. Female gender and pain in the upper extremities were the factors associated with NSP. The characteristics of NSP clarified in this study may provide a basis for the prevention and/or effective management of NSP.

Relationship Between Grip, Pinch Strengths and Anthropometric Variables, Types of Pitch Throwing Among Japanese High School Baseball Pitchers

Background: Grip and pinch strength are crucially important attributes and standard parameters related to the functional integrity of the hand. It seems significant to investigate normative data for grip and pinch strength of baseball players to evaluate their performance and condition. Nevertheless, few reports have explained the association between grip and pinch strength and anthropometric variables and types of pitch throwing for baseball pitchers. Objectives: The aim of this study was to measure and evaluate clinical normative data for grip and tip, key, palmar pinch strength and to assess the relationship between these data and anthropometric variables and types of pitch throwing among Japanese high-school baseball pitchers. Materials and Methods: One hundred-thirty three healthy high school baseball pitchers were examined and had completed a self-administered questionnaire including items related to age, hand dominance, throwing ratio of type of pitch. A digital dynamometer was used to measure grip strength and a pinch gauge to measure tip, key and palmer pinch in both dominant and nondominant side. Body composition was measured by the multi frequency segmental body composition analyzer. Results: Grip strength and tip and palmer pinch strength in dominant side were statistically greater than them in nondominant side (P < 0.05). There were significant associations between grip strength and height (r = 0.33, P < 0.001), body mass (r = 0.50, P < 0.001), BMI (r = 0.37, P < 0.001), muscle mass of upper extremity (r = 0.56, P < 0.001), fat free mass (r = 0.57, P < 0.001), fat mass (r = 0.22, P < 0.05) in dominant side. A stepwise multiple regression analysis revealed that fat free mass and tip, palmer, key pinch strength were predictors of grip strength in dominant side. No statistical significant correlations were found between the throwing ratio of types of pitches thrown and grip strength and tip, key, palmar pinch strength. Conclusions: Our result provides normative values and evidences for grip and pinch strengths in high school baseball pitchers.

A Clinical and Ultrasonographic Study of Risk Factors for Elbow Injury in Young Baseball Players

Purpose. To determine the risk factors for elbow injury and its association with glenohumeral internal rotation deficit among young baseball players. Methods. 229 baseball players aged 9 to 14 (mean, 11) years completed a self-administered questionnaire with items related to years of playing baseball, hours of training per weekday, days of training per week, and past and present experience of elbow pain. Two orthopaedic surgeons measured the range of motion of both shoulders and elbows. Another 2 orthopaedic surgeons performed ultrasonography to detect any elbow abnormality such as fragmentation of the medial epicondylar apophysis and osteochondritis dissecans of the capitellum. Using univariate and multivariable analyses, participants with or without elbow abnormality were compared to determine the risk factors for elbow abnormality. Results. Elbow abnormality was detected in 100 of the participants and comprised osteochondritis dissecans of the capitellum (n=18) and fragmentation of the medial epicondylar apophysis (n=82). Elbow abnormality was associated with being a pitcher, past and present experience of elbow pain, loss of elbow extension, and the side-to-side internal rotation difference. The 100 participants with elbow abnormality were stratified into symptomatic (n=57) or asymptomatic (n=43) of elbow pain. Those with elbow abnormality and elbow pain was associated with being a pitcher. Conclusion. Being a pitcher was a risk factor for both elbow abnormality and elbow pain. Nonetheless, 43% of baseball players with elbow abnormality were asymptomatic. The use of ultrasonography was effective in detecting elbow abnormality and enabling early treatment.

Compensatory hypertrophy of the teres minor muscle after large rotator cuff tear model in adult male rat

BACKGROUNDnRotator cuff tear (RCT) is a common musculoskeletal disorder in the elderly. The large RCT is often irreparable due to the retraction and degeneration of the rotator cuff muscle. The integrity of the teres minor (TM) muscle is thought to affect postoperative functional recovery in some surgical treatments. Hypertrophy of the TM is found in some patients with large RCTs; however, the process underlying this hypertrophy is still unclear. The objective of this study was to determine if compensatory hypertrophy of the TM muscle occurs in a large RCT rat model.nnnMETHODSnTwelve Wistar rats underwent transection of the suprascapular nerve and the supraspinatus and infraspinatus tendons in the left shoulder. The rats were euthanized 4 weeks after the surgery, and the cuff muscles were collected and weighed. The cross-sectional area and the involvement of Akt/mammalian target of rapamycin (mTOR) signaling were examined in the remaining TM muscle.nnnRESULTSnThe weight and cross-sectional area of the TM muscle was higher in the operated-on side than in the control side. The phosphorylated Akt/Akt protein ratio was not significantly different between these sides. The phosphorylated-mTOR/mTOR protein ratio was significantly higher on the operated-on side.nnnCONCLUSIONnTransection of the suprascapular nerve and the supraspinatus and infraspinatus tendons activates mTOR signaling in the TM muscle, which results in muscle hypertrophy. The Akt-signaling pathway may not be involved in this process. Nevertheless, activation of mTOR signaling in the TM muscle after RCT may be an effective therapeutic target of a large RCT.

Does successful rotator cuff repair improve muscle atrophy and fatty infiltration of the rotator cuff? A retrospective magnetic resonance imaging study performed shortly after surgery as a reference

BACKGROUNDnMuscle atrophy and fatty infiltration in the rotator cuff muscles are often observed in patients with chronic rotator cuff tears. The recovery from these conditions has not been clarified.nnnMETHODSnNinety-four patients were included in this study. The improvement in muscle atrophy and fatty infiltration in successfully repaired rotator cuff tears was evaluated by magnetic resonance imaging at 1 year and 2 years after surgery and was compared with muscle atrophy and fatty infiltration observed on magnetic resonance imaging at 2 weeks after surgery to discount any changes due to the medial retraction of the torn tendon. The patients muscle strength was evaluated in abduction and external rotation.nnnRESULTSnMuscle atrophy and fatty infiltration of the supraspinatus were significantly improved at 2 years after surgery in comparison to 2 weeks after surgery. The subjects abduction and external rotation strength was also significantly improved at 2 years after surgery in comparison to the preoperative values. Patients whose occupation ratio was improved had a better abduction range of motion, stronger abduction strength, and higher Constant score. Patients whose fatty infiltration was improved had a better range of motion in flexion and abduction, whereas the improvements of muscle strength and the Constant score were similar in the group that showed an improvement of fatty infiltration and the group that did not.nnnCONCLUSIONnMuscle atrophy and fatty infiltration can improve after rotator cuff repair. The strengths of abduction and external rotation were also improved at 2 years after surgery.

Effect of total knee arthroplasty on other joints in patients with rheumatoid arthritis evaluated by 18-FDG-PET

The objective of this study was to assess arthritis of the whole body before and after total knee arthroplasty (TKA) in patients with rheumatoid arthritis (RA) using positron emission tomography (PET).