The prevalence of OCD of the humeral capitellum, including latent cases, was 3.4% among adolescent baseball players. Players with OCD lesions began playing baseball at earlier ages, had played for longer periods, and had experienced more elbow pain. The player's current baseball position may not be related to the existence of OCD lesions in adolescents.

Rheumatoid arthritis (RA) is characterized by massive synovial proliferation, angiogenesis, subintimal infiltration of inflammatory cells and the production of cytokines such as TNF-α and IL-6. Allograft inflammatory factor-1 (AIF-1) has been identified in chronic rejection of rat cardiac allografts as well as tissue inflammation in various autoimmune diseases. AIF-1 is thought to play an important role in chronic immune inflammatory processes, especially those involving macrophages. In the current work, we examined the expression of AIF-1 in synovial tissues and measured AIF-1 in synovial fluid (SF) derived from patients with either RA or osteoarthritis (OA). We also examined the proliferation of synovial cells and induction of IL-6 following AIF-1 stimulation. Immunohistochemical staining showed that AIF-1 was strongly expressed in infiltrating mononuclear cells and synovial fibroblasts in RA compared with OA. Western blot analysis and semiquantitative RT-PCR analysis demonstrated that synovial expression of AIF-1 in RA was significantly greater than the expression in OA. AIF-1 induced the proliferation of cultured synovial cells in a dose-dependent manner and increased the IL-6 production of synovial fibroblasts and PBMC. The levels of AIF-1 protein were higher in synovial fluid from patients with RA compared with patients with OA (p < 0.05). Furthermore, the concentration of AIF-1 significantly correlated with the IL-6 concentration (r = 0.618, p < 0.01). These findings suggest that AIF-1 is closely associated with the pathogenesis of RA and is a novel member of the cytokine network involved in the immunological processes underlying RA.

The objective of this study was to investigate the effects of heat stimulation on the expression of extracellular matrix genes and heat-shock protein 70 (HSP70) in rabbit articular cartilage in vivo. Heat stimulation was applied to the knee joints of Japanese white rabbits for 20 min using a microwave (MW) applicator (2.45-GHz, 0-80 W). After 8-72 h, the articular cartilage was removed from the knee joints and proteins and total RNA were extracted. As controls, knee joints without heat stimulation were analyzed. The expression of HSP70 was confirmed by real-time PCR and Western blotting. The expression of proteoglycan core protein (PG) and type II collagen (Col II) was quantified using real-time PCR to assess cartilage matrix metabolism. Compared to controls, HSP70 expression was higher with more than 40 W of heat stimulation. The expression of PG and Col II mRNA was higher, with more than 20 W of heat stimulation and peaked with 40 W. When quercetin was used to inhibit the induction of HSP70 expression, PG mRNA expression did not increase. External MW application stimulated HSP70 expression in the articular cartilage in vivo. The expression of extracellular matrix genes was increased by appropriate heat stimulation. ß

Context: Previous research on American football injuries in Japan has focused on incidence proportion in terms of the number of injuries divided by the number of players. This is the first study to examine injury rates over several seasons.Objective Main Outcome Measure(s): A certified athletic trainer kept a daily record of all practice and game injuries. Injury rates were calculated according to season, injury type, body part, severity, and mechanism. Injuries were also analyzed according to position of player, school year, and playing experience.Results: The game injury rate (GIR; 32.7 injuries/1000 athlete-exposures) was higher than the practice injury rate (PIR; 10.9 injuries/1000 athlete-exposures) over the 3 seasons (P , .05). The PIR was higher among Japanese players than the comparable United States collegiate football injury rates (5.8-7.0 injuries/1000 athlete-exposures). Ankle and foot injuries occurred more frequently during games, whereas thigh and gluteal injuries occurred more frequently during practices.Conclusions: Our data show differences between games and practices in terms of injury rates, body parts injured, and positions of players injured. The high PIR in Japan may be due to the increased contact during practices and length of practices compared with the United States. Further research involving multiple teams is recommended to validate the trends noted in this study. The expanded data set could assist in the development of safety regulations and preventive interventions for Japanese football.Key Words: Japanese football, American football, college football, injury rates Key PointsThe practice injury rate for Japanese collegiate football players was higher than in the United States. This may be explained by the increased contact during practice and unregulated practice length in Japan. Ankle and foot injuries occurred more often during games, whereas thigh and gluteal injuries were more frequent during practices.

This study was designed to examine the effects of electroacupuncture with direct current (DC) on peripheral nerve regeneration. The left sciatic nerve of 55 7-month-old rats was crushed at the thigh. They were ramdomly allocated to four groups: distal cathode DC group (n=15), distal anode DC group (n=14), sham operated group (n=13), and control group (n=13). In the distal cathode DC group, a cathode electrode was connected to an insulated acupuncture needle inserted at 1 cm distal to the injured site, while an anode electrode was connected to a needle inserted at 1 cm proximal to the lesion. In the distal anode DC group, the anode and the cathode electrode were connected to the needle at 1cm distal and proximal to the lesion respectively. In the sham operated group, no electrical stimulation was given to the insulated needle inserted at the same site, and in the control group, no treatment was given. Regeneration of the sciatic nerve was evaluated by the number of evoked EMGs recorded at 12 sites in the plantar region, by their latency, and by the weight ratio of the tibialis anterior at four weeks after the crush injury. Regeneration of the peripheral nerve was faster and more accelerated in the distal cathode DC group than in the other groups, while in the distal anode DC group the regeneration was delayed. This result suggested electroacupuncture with cathode distal orientation might be a useful treatment having the advantage of enabling deeper insertion with minimal tissue damage.