The posterior tibial slope does not influence the flexion angle in posterior-stabilized mobile-bearing total knee arthroplasty.

Background: It remains uncertain whether an increase in the tibial slope leads to better flexion in posterior-stabilized (PS) total knee prostheses.

Purpose: To compare the intra-operative flexion angle between standard and an additional 10° posterior slope inserts.

Patients And Methods: Between December 2014 and February 2015, 22 patients (25 knees) who underwent PS mobile-bearing primary total knee arthroplasty (TKA) were included.

Joint Gap in Mid-Flexion Is Not a Predictor of Postoperative Flexion Angle After Total Knee Arthroplasty.

Background: Postoperative knee flexion angle is one of the most important outcomes of total knee arthroplasty (TKA). Intraoperative ligament balancing may affect the postoperative range of motion of the knee. However, the relationship between intraoperative ligament balancing and postoperative flexion angle was still controversial.

Decreased extension gap and valgus alignment after implantation of total knee prosthesis in primary varus knees.

Purpose: It was hypothesised that implantation of a total knee prosthesis may change the size and shape of the joint gap. To test this hypothesis, a tensor device was used which was specifically designed to reproduce the conditions before and after implantation, including attachment of the polyethylene insert trial. This study aimed to compare the joint gaps before and after implantation of a total knee prosthesis using this new tensor device.

Midflexion Laxity After Implantation Was Influenced by the Joint Gap Balance Before Implantation in TKA.

The relationship between the joint gap before and after implantation in 259 knees during the total knee arthroplasty was investigated using a tensor device which can attach the polyethylene insert trial. Patients were divided into following 3 groups according to the joint gap balance before implantation (flexion joint gap--extension joint gap); group 1: >1mm; group 2: -1 to 1mm, and group 3: <-1mm. Joint gap after implantation was loose at 30°, 60°, 90°, and 120° of flexion in group 1 and 2, but loose only at 30° of flexion in group 3 (p<0.

Intraoperative assessment of midflexion laxity in total knee prosthesis.

Background: Soft-tissue balancing of the knee is fundamental to the success of a total knee arthroplasty (TKA). In posterior-stabilized TKA, there is no stabilizer of the anterior-posterior translation in the midflexion range in which the cam-post mechanism does not engage yet. Therefore, instability in the midflexion range is suspected to occur in posterior-stabilized TKA.