The Coronal Plane Alignment of the Knee (CPAK) classification has been developed to predict individual variations in inherent knee alignment. The impact of preoperative and postoperative CPAK classification phenotype on the postoperative clinical outcomes of total knee arthroplasty (TKA) remains elusive. This study aimed to examine the effect of postoperative CPAK classification phenotypes (I to IX), and their pre- to postoperative changes on patient-reported outcome measures (PROMs). A questionnaire was administered to 340 patients (422 knees) who underwent primary TKA for osteoarthritis (OA) between September 2013 and June 2019. A total of 231 patients (284 knees) responded. The Knee Society Score 2011 (KSS 2011), Knee injury and Osteoarthritis Outcome Score-12 (KOOS-12), and Forgotten Joint Score-12 (FJS-12) were used to assess clinical outcomes. Using preoperative and postoperative anteroposterior full-leg radiographs, the arithmetic hip-knee-ankle angle (aHKA) and joint line obliquity (JLO) were calculated and classified based on the CPAK classification. To investigate the impact on PROMs, multivariable regression analyses using stepwise selection were conducted, considering factors such as age at surgery, time since surgery, BMI, sex, implant use, postoperative aHKA classification, JLO classification, and changes in aHKA and JLO classifications from preoperative to postoperative.Aims
Methods
The aim of this study was to compare the post-operative radiographic
and clinical outcomes between kinematically and mechanically aligned
total knee arthroplasties (TKAs). A total of 60 TKAs (30 kinematically and 30 mechanically aligned)
were performed in 60 patients with varus osteoarthritis of the knee
using a navigation system. The angles of orientation of the joint
line in relation to the floor, the conventional and true mechanical
axis (tMA) (the line from the centre of the hip to the lowest point
of the calcaneus) were compared, one year post-operatively, on single-leg
and double-leg standing long leg radiographs between the groups.
The range of movement and 2011 Knee Society Scores were also compared
between the groups at that time.Aims
Patients and Methods