To evaluate the clinical outcome of knee synovial chondromatosis treated arthroscopically with local anesthesia.
From August 2010 to February 2015, 67 patients with knee joint synovial chondromatosis were arthroscopically treated under local anesthesia in our hospital. The patients included 41 males and 26 females with average age of 45.2 years old ranged from 26 to 67 years, with the lesion involving right knees in 36 and left knees in 31patients. Before operation, all the 67 patients were clearly diagnosed as knee joint synovial chondromatosis，associated with clinical manisfestration of knee pain, swelling and locking. X-ray film was taken immediately after operation and at 4, 8, 24 weeks postoperatively.VAS, Lysholm score, IKDC 2000 score as well as range of motion were determined before the operation and at the last follow-up for evaluation of the clinical outcomes.
All the patients were followed up for an average of 29.6 months ranged from 22 to 47 months. All the patients had primary healing of the incisions without complications. Compared with the preoperative data, VAS （5.1±1.4 versus 1.2±0.5, P=0.021）, Lysholm score （50.22±6.23 versus 78.19±7.15, P<0.001）, IKDC score（61.36±6.14 versus 80.07±5.32, P<0.001）and range of motion（68.8±9.2 versus 96.6±8.7, P=0.008）statistically improved at the latest follow-up.
Arthroscopic surgery for treatment of knee synovial chondromatosis with local anesthesia does achieve satisfactory median-term outcome, with advantages of minimized surgical trauma, thorough resection of the lesion and early functional recovery.