RESUMEN
Objective To study the causes and symptoms about locking knee of unclear causes and analyze the thrapeutic effects of arthroscopy. Methods Arthroscopy was performed for 47 cases who suffered from locking knee of unclear causes.The main focuses observed were synovial shelf(16 cases),synovial hyperplasia(15 cases),synovial cyst(3 cases),Hoffa disease(4 cases)and patellofemoral malalignment(9 cases).These synovial focuses were resected by arthroscopic shaving.For Hoffa disease,arthroscopic partial resection of the infrapatellar fat pad was done.For patellofemoral malalignment,the procedures consisted of a standard lateral retinacular release and distal realignment of the patella. Results All patients were followed up for 2 months to 3 years on (an average of 1 year).The locking of knee disappeared for all cases and painless of knee for 46 cases.The functional recoveries of Knee joint were mostly excellent. Conclusions The main causes consisted of synovial shelf?hyperplasia?cyst,Hoffa disease and patellofemoral malalignment for locking knee of unclear causes.Arthroscopy is not only an important diagnostic method,but also a significant procedure of treatment and the therapeutic effects are satisfactory.