Boettner F, et al. - This study was intended to compare individuals undergoing total knee arthroplasty (TKA) with ≤ 80° range of movement (ROM) operated with a 2 mm increase in the flexion gap with matched non-stiff patients with at least 100° of preoperative ROM and balanced flexion and extension gaps. Researchers designed a retrospective cohort study to included a total of 98 TKAs (91 patients) with a preoperative ROM of ≤ 80°. With a mean follow-up of 43 months (24 to 89), data were correlated to a matched control group of 98 TKAs (86 patients). They used in all stiff and non-stiff knees posterior stabilized (PS) TKAs with patellar resurfacing in combination with adequate soft tissue balancing. A significant improvement of ROM in knees with preoperative stiffness was found by TKA with a 2 mm increased flexion gap. The absolute postoperative ROM was less than in matched non-stiff knees, although the improvement in ROM was greater. When stiffness of the knee had been present preoperatively, PS TKA with patellar resurfacing and a 2 mm increased flexion gap, in combination with adequate soft tissue balancing, serves excellent ROM and knee function.