RESUMO
PURPOSE: The purpose of this study is to evaluate the usefulness of the trans-septal approach for treating popliteal cyst, to determine the frequency and types of the associated pathologies and to assess the follow up ultrasound evaluation. MATERIALS AND METHODS: From February, 2002 to February, 2007, 44 patients with popliteal cyst were treated by arthroscopy only. Fourteen patients were male and 30 patients were female. Their average age was 50 years (range: 20~77 years). We used the trans-septal portal approach. We evaluated the satisfaction of the patients and the recurrence of the popliteal cyst by performing ultrasound exams at an average follow up of 36 months after surgery. At the final follow up, we evaluated the clinical results by the criteria of Rauschning and Lindgren. RESULTS: We found no communication between the knee joint and the popliteal cyst by CT or MRI in 4 cases (8%), but we found a communication by arthroscopy in all the cases. Thirty-four cases had intra-articular pathologies and 9 cases didn't. The total intra-articular pathologies included 17 articular cartilage defects or chondral lesion (38%) and 15 meniscus tears (34%). In 1 case, open excision was performed for the revision surgery because the patient had recurrence of the popliteal cyst, which caused compressive neuropathy of the common peroneal and tibial nerve. At the last follow up, the clinical outcome of surgery according to the criteria of Rauschning and Lindgren was grade 0 (28 cases), grade1 (12 cases), grade 2 (3 cases) and grade 3 (1 case). CONCLUSION: We can approach the orifice of a popliteal cyst directly with using the trans-septal portal and easily decompress the orifice of the cyst. We propose that the arthroscopic decompression using the trans-septal portal is an excellent treatment modality for popliteal cysts.