While few comparative studies exist, it has been suggested that open resection of Hoffa's fat pad tumor like provide inferior results when compared with the all-arthroscopic technique.

The purpose of this study was to compare the intermediate-term results of patients undergoing arthroscopic versus open resection for the treatment of tumor like of Hoffa's fat pad.

We prospectively reviewed records from 2010–2013 and identified 27 patients (18 arthroscopic, 9 open) with symptomatic Hoffa's fat pad impingement. The mean follow-up for group I (open) and group II (arthroscopic) was 2.3 years and 1.2 years, respectively. The diagnosis was made by clinical exam, MRI imaging and verified by anatomopathology. Lysholm score was obtained pre- and postoperative and at final follow-up. Each patient completed a questionnaire assessing their scar satisfaction, percentage of normal knee function and willingness to have the surgery again. Risk factors for poor outcomes were analyzed.

There was a significant improvement in their symptoms and function after the surgery at an average follow-up of 14 months. Arthroscopic patients had significantly less pain (P=0.035) by VAS (0.61±1.02) compared with open (1.59±2.15) at final follow-up. Percentage of normal knee function (89.7%±12.5 vs. 92.9%±8.6), average operative time (53.1minutes vs. 41minutes). The one poor result was because of paresthesia over the distribution of the infrapatellar branch of the saphenous nerve after open resection.

Open and arthroscopic resection of infrapatellar fat pad are both effective surgeries. Tumors like of the fat pad should be treated by arthroscopic resection because of less residual pain and less complication was found using the arthroscopic technique. In case of high volume of tumors only open excision can provide complete excision.