Arthrofibrosis (AF) after total knee arthroplasty (TKA) is still a controversial issue particularly regarding the different recommended treatment options [2, 4–6, 11, 25]. In robot-assisted TKA, there is an assumed lower rate of AF by using a robot [1] due to greater precision achieved with tibial slope reconstruction, which is seen as contributing to decreased flexion ability. In general, AF is a severe complication after TKA with several therapy options: manipulation under anesthesia (MUA), arthroscopic or open lysis of adhesions (aLOA) or revision TKA (rTKA) [2]. We present two cases of probable infection-associated AF: one after primary TKA and the other after rTKA. Both patients were treated identically with a three-stage procedure, but with significantly different outcomes. The patients suffered from very limited range of motion. In both patients, it was necessary to perform tibial tubercle osteotomy in order to expose the knee for explantation and/spacer implantation in the first revision as well as in the two-stage reimplantation after 6 weeks. After re-implantation, flexion restriction above 45° was required to protect the tibial tuberositas refixation. Both patients developed severe extension-contracture 9 weeks after the second stage rTKA and were therefore revised after 6 months by extensive open arthrolysis and mobilization. After this procedure, the postoperative protocol with continuous passive motion (CPM) 12 h/day under anesthesia for 1 week and without anesthesia for a further 6 weeks and additional physiotherapeutic treatment and lymphatic drainage for 3 months was initiated. Both cases and preliminary results are presented.
