Nishida, Keiichiro

We studied the magnetic resonance imaging (MRI) of 120 knees in 86 rheumatoid arthritis (RA) patients and of 14 unaffected knees in 12 control cases. We also developed a scoring system as a quantitative analysis method. We divided the MRI into 10 items, and classified the severity of the symptoms into 4 grades (score 0 to 3). The average total score increased according to the radiographic grade. Soft tissue lesions were clearly detected, even in the early stages of RA. Items such as synovial proliferation showed a high score even in the early stages, suggesting that it was the initial symptom of RA. The score also showed a correlation with the inflammatory signs. These results suggest that this scoring system is very sensitive and yields a good reflection of RA activity. We demonstrated that this system is simple and convenient for routine diagnostic use. We further demonstrated that it is useful for following the advancement of RA and for evaluating the response to treatment.

Mast cells in osteoarthritic and rheumatoid arthritic synovial tissues of the human knee.

The fibrous components of the metacarpophalangeal (MP) joint including the palmar plate, the collateral ligament and the dorsal plate were studied with particular attention paid to the fibrous structure of the fibrous tendon sheath and the deep transverse metacarpal ligament. The tough fibrillar structure around the MP joint, especially the force nucleus, consisted of three types of mixed fibers: the fibrous tendon sheath of the A1 pulley, the deep transverse metacarpal ligament, and the palmar plate. The tendon sheath was located on the ulnar side in the index and middle fingers, on the central position in the ring finger, and on the radial side in the little finger. These fibrous connections among the fingers formed a transverse arch in the hand. The palmar plate of the MP joint was relatively rigid and appears to function as a cushion when flexed. A fold-like protrusion of the synovial layer of the palmar plate of the MP joint had a meniscoid function, which was larger than that of the proximal interphalangeal joint. The capsule of the MP joint was thicker at the dorsal area, forming a dorsal plate, which is a sliding floor of the extensor mechanism and has a meniscoid function for joint congruity. The main lateral stabilizer consisted of collateral ligaments and accessory collateral ligaments anchored to the palmar plate. These structures act together as a "phalangeal cuff", connecting the proximal phalanx to the metacarpal head and sta

The expression of osteonectin (ON) in osteoarthritic articular cartilage was investigated by enzyme immunohistochemistry and colloidal gold immunoelectron microscopy. A total of 96 specimens from 9 knees of 8 patients with osteoarthritis (OA) were examined. In OA cartilage, ON-positive cells varied in distribution and were not seen in all the specimens obtained from the same patient. However, in over half of the specimens (56 of 96), especially in the specimens of Mankin's grades from 4 to 9, which corresponds to relatively early stages of OA, ON was expressed in the cartilage above the calcified layer. On the other hand, ON was detected only in the calcified layer below the tidemark in normal articular cartilage. In addition, colloidal gold immunoelectron microscopy revealed ON in chondrocytes and matrix vesicles (MVs). These findings suggest that ON acts through MVs in the early stages of OA as a significant pathogenetic factor involved in intracartilage calcification, which is known to have a close relationship to the progression of OA.

Sixty-seven trigger fingers of 58 idiopathic and hemodialysis patients were treated by percutaneous A1-pulley release technique. Severity of triggering was classified into five grades for treatment selection and prediction of possible results. Results were excellent in 41 fingers, good in 9, fair in 7, and poor in 10, requiring additional treatment. The results of the lower grades were better, and those of the higher grades were poor. Excellent or good results appeared to depend on the proper selection of the patients according to the grading system and confirmation of triggering disappearance just after the release. There were neither infections nor neuro-vascular deficits after treatment. Compared to conventional open release, this treatment was found to be more useful from the standpoints of ease and safety of the technique, and the patients' quick return to normal life.

The results of the histological examinations of specimens of the tenosynovium of the flexor tendon, the epineurium and the transverse carpal ligament from two groups of Japanese patients with carpal tunnel syndrome (idiopathic and hemodialysis) were compared. Amyloid deposits, positively identified as β₂-microglobulin, appeared in all patients in the long-term hemodialysis group, but in no patients in the idiopathic group. Although the pathogenesis differed between the two groups, both resulted in nerve compression in the carpal tunnel. Therefore, surgical release is considered beneficial for both groups.

Localization of the glycosaminoglycans (GAG) was examined in the synovial membranes of patients with osteoarthritis under light microscopy using a fine cationic colloidal iron staining method combined with enzymatic digestion. Our staining method was very useful for demonstrating the difference in the localization of GAG in regions of the inflammatory site in the osteoarthritic synovial membrane. Hyaluronic acid was mainly located in connective tissues in the surface intercellular and perivascular spaces, chondroitin sulfate A/C in the highly fibrous part of and connective tissue around blood vessels, dermatan sulfate (chondroitin sulfate B) in the subsurface interstitium and vascular endothelial cells and heparan sulfate in part of vascular endothelial cells. No keratan sulfate was detected. GAG is reported to have an important role in cell movement, adherence and aggregation in the inflammatory sites. These findings should be useful for understanding the role of GAG in physiological and pathologic processes of secondary synovitis.