[Clinical prospective comparative study on short-term effectiveness of arthroscopic treatment of popliteal cyst between cyctectomy and internal drainage combined with cyctectomy].

OBJECTIVE

To compare the short-term effectiveness between arthroscopic cystectomy and internal drainage combined with cystectomy in popliteal cyst.

METHODS

Between March 2014 and March 2017, 56 patients with symptomatic popliteal cyst were enrolled in the study, randomized block design was used to divided the patients into trial group (arthroscopic cystectomy combined with internal drainage group, =28) and control group (arthroscopic internal drainage group, =28). Excluding those who had incomplete follow-up and received surgery for other diseases postoperatively, 26 patients in the experimental group and 27 patients in the control group were finally enrolled in the study. There was no significant difference in gender, age, side, course of disease, maximum diameter and grade of popliteal cyst, and associated diseases between two groups ( >0.05). The operation time, duration of popliteal ecchymosis and the middle back of calf tenderness were observed postoperatively. The circumference of calf at 1 day, 1 week, and 2 weeks after operation were measured and the differences were calculated with the measurement before operation. Lower extremity venous thrombosis was observed by color doppler ultrasonography at 1 week after operation. The effectiveness was evaluated by Rauschning and Lindgren grading criteria. And MRI was used to observe whether the popliteal cyst disappeared or decreased and measured its maximum diameter at 1 year after operation.

RESULTS

Patients in both groups were followed up 12-14 months, with an average of 12.5 months. The operation time, duration of popliteal ecchymosis, and the middle back of calf tenderness of the trial group were all longer than those in the control group ( <0.05), the differences of circumference of calf at 1 day, 1 week, and 2 weeks after operation of the trial group were greater than those in the control group ( <0.05). Color doppler ultrasonography of the lower extremity at 1 week after operation found that the intermuscular venous thrombosis occurred in 2 cases of the trial group, while no lower extremity thrombosis was found in the control group; and the difference between two groups was not significant ( =0.236). According to the Rauschning and Lindgren grading criteria, there were 16 cases of grade 0, 6 cases of grade 1, and 4 cases of grade 2 in the trial group, and 17 cases of grade 0, 4 cases of grade 1, and 6 cases of grade 2 in the control group at 1 year after operation. There was no significant difference between 2 groups ( =-1.872, =0.078). Nine cases (34.62%) of the trial group and 13 cases (48.15%) of the control group still have residual cysts by MRI, the maximum diameter of which was less than 2 cm. The cysts disappeared in the remaining patients in both groups, and there was no recurrence during the follow-up. There was no significant difference in cyst residual rate between 2 groups ( =2.293, =0.852).

CONCLUSION

Compared with arthroscopic internal drainage, the short-term effectiveness of the arthroscopic internal drainage combined with cystectomy had no significant improvement, and the operation time was prolonged, the postoperative complications were obviously increased.