Shogo Toyama

Prediction of radiographic progression in synovitis-positive joints on maximum intensity projection of magnetic resonance imaging in rheumatoid arthritis

Contrast-enhanced magnetic resonance imaging with maximum intensity projection (MRI-MIP) is an easy, useful imaging method to evaluate synovitis in rheumatoid hands. However, the prognosis of synovitis-positive joints on MRI-MIP has not been clarified. The aim of this study was to evaluate the relationship between synovitis visualized by MRI-MIP and joint destruction on X-rays in rheumatoid hands. The wrists, metacarpophalangeal (MP) joints, and proximal interphalangeal (PIP) joints of both hands (500 joints in total) were evaluated in 25 rheumatoid arthritis (RA) patients. Synovitis was scored from grade 0 to 2 on the MRI-MIP images. The Sharp/van der Heijde score and Larsen grade were used for radiographic evaluation. The relationships between the MIP score and the progression of radiographic scores and between the MIP score and bone marrow edema on MRI were analyzed using the trend test. As the MIP score increased, the Sharp/van der Heijde score and Larsen grade progressed severely. The rate of bone marrow edema-positive joints also increased with higher MIP scores. MRI-MIP imaging of RA hands is a clinically useful method that allows semi-quantitative evaluation of synovitis with ease and can be used to predict joint destruction.

Spontaneous flexor tendon rupture due to an insufficiency fracture of the hamate hook in a patient with systemic lupus erythematosus: A case report

Highlights • We report a case of spontaneous flexor tendon rupture in a patient with SLE.• Nonunion of the hamate hook is one of the causes of flexor tendon rupture.• SLE patients have an increased risk for osteoporosis and insufficiency fractures.• Tenosynovitis and long-term steroid use can affect tendon integrity in SLE.• SLE can lead to both tendon degeneration and insufficiency fracture of the hamate.

A new assessment tool for ulnar drift in patients with rheumatoid arthritis using pathophysiological parameters of the metacarpophalangeal joint

Abstract Objectives: To establish a new assessment tool for ulnar drift (UD) in rheumatoid arthritis (RA). Methods: We established an observational cohort of 67 patients (134 rheumatoid hands) beginning in 2004. Fifty-two patients (100 hands) had follow-up in 2009 and 37 patients (63 hands) completed follow-up in 2015. UD was evaluated with the Fearnley classification and our scoring method, which assesses four parameters of the metacarpophalangeal joint. Cluster analysis using UD parameters divided hands into groups. Changes in UD over time, correlation of the Fearnley stage and cluster with a functional assessment, and reliability of the parameters were analyzed. Results: UD increased and worsened over time according to the trend test. A dendrogram indicated five clusters would be appropriate. Both the Fearnley classification and cluster were associated with function; however, our method related to function more linearly (R-squared: 0.42). We found one type of hand in which bone destruction precedes the joint dislocation and one type in which joint dislocation progresses with little deviation during UD progression. Conclusion: Our UD evaluation appeared to be simple and related to function. Additionally, it enables dividing UD hands into five stages. Thus, our assessment should be beneficial compared to the Fearnley classification in considering treatments of UD.

Kinematic, kinetic, and electromyographic characteristics during quiet standing on a balance exercise assist robot

[Purpose] The balance exercise assist robot is a training device based on a personal transport assistance robot ridden in the standing position. The personal transport assistance robot uses an inverted pendulum control system and moves in response to movements of the user’s center of gravity. The purpose of this study was to describe the characteristics of postural control during the action of stopping the personal transport assistance robot. [Participants and Methods] Eleven healthy male participants were required to maintain a standing position for 30 s; each task was performed 10 times. The measurement conditions were as follows: (1) on the floor; (2) on the robot, touching the handlebars; and (3) on the robot, not touching the handlebars. [Results] During the robotic tasks, the total locus lengths of the center of gravity and total joint momentums of the hip, knee, and ankle joints were larger, and the amount of displacement of the center of pressure was smaller than that during the floor task. Posture control on the robot was performed actively by mechanical interaction of the ankle, knee, and hip joints within a small base of support. [Conclusion] The balance exercise assist robot can be useful for postural control exercises because maintaining a standing position on the personal transport assistance robot required active postural control.

Five-decade-delayed closed flexor tendon rupture due to Galeazzi dislocation fracture associated with Behçet syndrome: A case report

Highlights • Delayed flexor tendon rupture after Galeazzi dislocation-fracture is unusual.• Even minimal capsule damage can influence tendon degeneration.• Corticosteroid usage or a collagen disease may contribute to tendon sensitivity.• Even minimal past trauma-related damage is vital in sensitive cases.

A kinematic and kinetic analysis of the hip and knee joints in patients with posterior tibialis tendon dysfunction; comparison with healthy age-matched controls

BACKGROUND The biomechanical abnormalities in patients with posterior tibial tendon dysfunction (PTTD) have been described, but few studies have investigated biomechanical chains of adjacent joints. Therefore, we examined the gait pattern of the lower extremity in subjects with PTTD, focusing on the hip and knee joints. METHODS We compared 19 PTTD patients (average age: 67.1) with 30 age-matched control subjects (average age: 65.1). Gait analysis was performed with a nine-camera motion-capture system and four force plates, using the Vicon Plug-In-Gait and Vicon Nexus software. Temporal-spatial parameters were compared between PTTD and control subjects, and motion and ground reaction force data were compared between the affected limb, the contralateral limb, and the right limb in control subjects. RESULTS Subjects with PTTD had increased stance phase ratio and decreased stride length, cadence, and gait speed. The limbs of subjects with PTTD showed increased knee internal rotation at lording response, which was biased to abduction in the knee joint during the gait cycle, and irregular hip flexion and knee extension moment in the terminal stance, even under control of gait speed. SIGNIFICANCE We believe that the subjects with PTTD have an increased risk of knee osteoarthritis in both the affected and contralateral limbs.

Recurrence of deformity after silicone implant and resection arthroplasty of the metatarsophalangeal joint for rheumatoid arthritis: long-term results.

Abstract Objective: To examine the recurrence of deformity after silicone implant arthroplasty combined with resection arthroplasty for severe forefoot deformity in patients with rheumatoid arthritis. Methods: We reviewed the long-term results of this procedure for 27 feet in 15 patients. Their average age and disease duration at the time of operation were 58.6 years and 17.5 years, respectively, and the average follow-up period was 10.3 years. Results: An improved hallux valgus angle (45.3° preoperatively, 23.6° 6 months after operation) was maintained. By contrast, deformity and dislocation of lesser toe had recurred at the final follow-up; the angle between the proximal phalanx and the metatarsal of the second toe improved 13.4° with recurrence of 22.5°, the angle between the proximal phalanx and ground surface improved 22.4° with recurrence of 34.5. Furthermore, claw toe deformity at the final follow-up was significantly worse in the group whose hallux valgus deformity was observed 6 months after operation. Conclusion: This procedure could maintain the alignment of the first metatarsophalangeal joint, but the recurrence of claw toe deformity is a problem and the relation between the first toe and the lesser toe is an important consideration.

Dynamic close-mouth view radiograph method for the diagnosis of lateral dynamic instability of the atlantoaxial joint

The purpose of the current study is to establish the dynamic close-mouth view radiograph method. Seven healthy volunteers were enrolled. Dynamic open-mouth and close-mouth view radiographs were obtained. The odontoid lateral mass interval and the dynamic atlantodental lateral shift (ADLS) were measured. The ADLS was 9.4+/-5.3% by the close-mouth view, showing a significantly greater percentage than that of 5.3+/-4.0% by the open-mouth view. The dynamic close-mouth view can be useful for diagnosis of atlantoaxial lateral instability.