Objective:To investigate the effect of blood flow restriction training (BFRT) on the rehabilitation of lower limb joint function in persons with rheumatoid arthritis (RA).Methods:Sixty RA patients were randomly divided into an observation group and a control group, each of 30. Both groups were given conventional slow-acting anti-rheumatic medication with low-dose glucocorticoids. Everyone received basic exercise training including joint training and plyometric training, but the observation group additionally received BFRT training during which constant pressure in an inguinal cuff restricted blood flow to the lower limbs. The observation group′s training program also included double leg push-ups and double knee extensions. Before, and 12 weeks after the intervention, the joint symptoms were assessed using swollen joint counts out of 28 joints (SJC28), tender joint counts out of 28 joints (TJC28) and pain reported using a visual analogue scale (VAS). Lower limb motor functioning was assessed using a timed-stands test (TST) and the timed-up-and-go (TUG) test. Life quality was evaluated using a health assessment questionnaire (HAQ) and arthritis self-efficacy scale-8 (ASES-8). Disease activity was quantified using a clinical disease activity index (CDAI), a simplified disease activity index (SDAI) and disease activity scoring with a 28-joint count (DAS28).Results:There were no significant differences between the two groups before the intervention. After the intervention all of the indicators except the DAS28 had improved significantly in the observation group. At that point they were also all better than the control group′s averages, where no significant improvement was observed. No serious adverse events occurred in either group during the experiment.Conclusions:BFRT can safely relieve joint symptoms and improve the lower limb motor functioning and life quality of RA sufferers. It is worthy of further clinical research and promotion.

As a special kind of in vitro diagnostic devices（IVDs）, laboratory developed tests（LDTs） are of great significance to the development of clinical laboratories. This study aims to explore the regulatory requirements ideas of LDTs. By introducing the development of LDTs and the changing of regulatory requirements in the United States, combing the current regulatory framework and discussing relevant ideas in the regulatory requirements of LDTs.
Clinical Laboratory Services ; Laboratories ; Reagent Kits, Diagnostic ; United States ; United States Food and Drug Administration