TREATMENT RESULTS OF PRIMARY KNEE OSTEOARTHRITIS BY ENDOSCOPY AT THAI NGUYEN HOSPITAL CENTRAL Objective: To evaluate the results of treatment of primary knee osteoarthritis endoscopic intervention at the Thai Nguyen Hospital Central Subjects: 38 patients were diagnosed with primary knee osteoarthritis according to ACR 1991 criteria were evaluated clinically before, immediately after treatment and follow-up endoscopic surgery after 1 month (T1), after 3 months (T3) at the Thai Nguyen Hospital Central from March 1/2013 - 5/2015. Research: Methodology intervention (clinical trials do not control).