Adoption of a new gait system to evaluate the clinical effects of minimally invasive needle-knife scope therapy for the treatment of rheumatoid arthritis of the knee joint.

BACKGROUND: The purpose of this study was to use kinematic gait analysis, to evaluate the clinically curative effects of minimally invasive needle-knife scope therapy in the treatment of rheumatoid arthritis (RA) of the knee joint. METHODS: A total of 32 patients with RA of the knee joint were treated with minimally invasive needle-knife scope therapy. All patients were assessed with a kinematic gait analysis system, and then analyzed and compared the measurements with the kinematic gait performances of 28 healthy middle-aged and elderly participants. RESULTS: Before receiving the therapy, the ranges of motion (ROMs) of the patients' tibial inward and outward rotation, flexion and extension, anterior and posterior displacement of the tibia, and tibial upward and downward movement were all smaller than those of the healthy middle-aged and elderly group (P<0.05). After receiving the therapy, the patients' knees had a remarkably larger ROM. After one month of this therapy, they had a noticeably greater ROM in flexion and extension, tibial inward and outward rotation, and upward and downward movement of the tibia (P<0.05). After 1 month of therapy, the patients' maximum flexion angle and tibial posterior displacement angle were noticeably greater than beforehand (P<0.01). After 1 year of therapy, the patients' flexion and extension range became remarkably greater than it was after 1 month of the therapy (P<0.01). Their ranges of DOF reflected no apparent difference to the healthy middle-aged and elderly group, which remained smaller than the latter (P<0.05). After 1 year of therapy, the maximum values of the patients' flexion angle, tibial internal rotation angle, tibial posterior displacement angle, and tibial downward movement angle were remarkably higher than before commencing treatment (P<0.05). CONCLUSIONS: Minimally invasive needle-knife scope therapy enables a good recovery of function for patients with RA and remarkably improves the DOF of knees. Gait analyses are more objective, accurate, and quantitative than other indexes, and thus may become a new means to assess the changes in knee joint functions.