ROLE OF INFRAPATELLA FAT PAD ON PRIMARY TOTAL KNEE ARTHROPLASTY

Abstract

The purpose of this study in to investigate the role of infrapatellar fat pad on primary total knee arthroplasty. We evaluated 100 patients who had been undergone TKA from August 2002 to July 2003, with open box posterior substituting femoral component implant (Scorpio PS Knee^™). The study was performed prospectively and randomly allocated. We divided two groups. Group 1 (50 knees) was preserved infrapatellar fat pad and repaired fad at wound closure. Group 2 (50 knees) was excised infrapatellar fat pad as possible and repaired only joint capsule. We analyzed and compared clinical results of Knee Society knee (KS) score, function score, patellar score and Insall-Salvati ratio in both groups. The complications of each group were evaluated. Patients were followed up for mean 40 months(17~52 months).

Mean KS score was 91.9 (91.94±5.58) in Group 1 and 90.9(90.92±6.38) in Group 2. Mean function score was 81.6(81.64±13.18) in Group 1 and 83.7(83.79±17.71) in Group 2. Mean patellar score was 29.9(29.89±9.10) in Group 1 and 27.9(27.90±1.80) in Group 2. And mean patellar height as Insall-Salvati ratio was 1.19(1.19±0.17) in Group 1 and 1.23(1.23±0.11) in Group 2. The differences between the Group 1 and Group 2 in all of index were statistically insignificant. In complications, 2 cases of recurrent hemarthrosis were observed in Group 1 patients.

We concluded The difference of clinical outcomes whether infrapatellar fat pad was excised or not were statistically insignificant. However, preservation of infrapatellar fat pad on open boxed PS TKA showed unique complications such as recurrent hemarthrosis which might be caused by fat pad adhesion to intercondylar notch. We propose that infrapatellar fat pad on primary PS TKA with open box design would like to be excised for prevention of unique complications.