OBJECTIVETo compare the roles of open synovectomy and arthroscopic synovectomy in the treatment of diffuse pigmented villonodular synovitis (D-PVNS).

METHODSForty-seven patients suffered from D-PVNS of knee joint who underwent surgical treatment with complete follow-up data from March 1994 to October 2013 were retrospectively analyzed. All patients were divided into two groups as open synovectomy group (n=17) and arthroscopic synovectomy group (n=30) according to the surgical procedure. Routine radiation therapy was applied in both groups after the surgery. The mean follow-up period wa s(15.7 ± 16.3) months (range:10-30 month). The range of motion, International Knee Documentation Committee (IKDC) score and Lysholm score before the surgery and at the final follow-up were compared respectively.

RESULTSRecurrence was noted in 8 patients (17.0%), among whom 3 were from the open synovectomy group and 5 from the arthroscopic synovectomy group, resulting a recurrence rate of 17.6% and 16.7%, respectively, in these two groups (P>0.05). The range of motion,IKDC score, and Lysholm score at final follow-up and before the operation were (97.5 ± 14.3)℃ vs.(69.7 ± 12.6)℃, (74.5 ±6.1) vs. (38.6 ± 5.4) scores, and (77.5 ± 5.8) vs. (42.4 ± 4.6)scores, respectively, in the open synovectomy group,and were (128.6 ± 13.9)℃ vs. (64.9 ± 13.2)℃, (87.4 ± 6.7) vs. (37.2 ± 4.9)scores, and (86.2 ± 6.2) vs. (41.9 ± 5.3) cores, respectively, in the arthroscopic synovectomy group (all P<0.05). Obviously,the range of motion,IKDC score, and Lysholm score at the final follow-up were significantly superior to the pre-operative findings, and were also significantly better in the arthroscopic synovectomy group than in the open synovectomy group (P<0.05).

CONCLUSIONSOpen synovetomy and arthroscopic synovetomy have similar recurrent rates in treating D-PVNS of the knee joint, while the latter has better postoperative range of motion and functional scores. Thus, arthroscopic synovectomy is a better option for the surgical treatment of D-PVNS.