Clinical symptoms caused by intra-articular fibrous plicae after knee replacement. Arthroscopic diagnosis and therapy.

In 29 patients with persistent complaints after knee replacement we found intra-articular fibrous tissue in different areas of the joint. In 26 patients diagnostic arthroscopy was followed by arthroscopic resection of the tissue. The fibrous tissue was differentiated into five types. Type 1 represented a transverse fibrous band located at the superior margin of the femoral component of the prosthesis. A type 2 plica was a lateral plica extending from the superolateral border of the patella to the infrapatellar fat pad. The type 3 fibrous band reached from the inferior pole of the patella to the intercondylar area. The type 4 nodulus was located at the superior border of the patella, and the type 5 plica was a meniscoid-like tissue between the femoral and the tibial component. Arthroscopic resection resolved the symptoms in 25 of the patients. Different factors seem to contribute to the development of intra-articular plicae after knee alloarthroplasty.