Abstract
Introduction
Mechanical axis limb alignment in total knee arthroplasty (TKA) has demonstrated excellent long-term survivorship; however, patient satisfaction continues to demand improvement. Alternative emerging alignment concepts including kinematic and tibial constitutional varus have been introduced but remain controversial. The purpose of this study was to evaluate outcomes and patient satisfaction following TKA with tibial components placed in constitutional varus alignment.
Methods
This was a retrospective cohort analysis from a total joint registry of 114 patients with preoperative varus deformity who underwent primary TKA with tibial component placed in 1–3 degrees of constitutional varus. The group included 59 males (52%) and 55 (48%) females with a mean age of 67 years (range 43 – 85) and mean BMI of 32.0 kg/m2 (range 21 – 51 kg/m2) with a minimum 1 year follow-up. Patients were stratified into 3 groups based on the preoperative varus alignment: Group A between 1°- 5° varus (43 knees), Group B between 6°- 10° (56 knees), and Group C greater than 10° (16 knees). The target constitutional tibial varus alignment was selected based on the extent of the patient's deformity.
Results
The average overall patient satisfaction was 4.7 on a 5-point Likert scale with 93% being either very satisfied or satisfied. Group A had the highest overall patient satisfaction of 95% followed by Group B (93%) and Group C (88%). Mean Forgotten Joint Score (FJS-12) for the combined groups was 86, mean KOOS Jr. score 72, mean WOMAC score 90, mean Knee Society (KS) Knee Score 93 and mean KS Function Score was 85.
Conclusion
The push for more patient centered outcome measures drives the pursuit of improving patient satisfaction in addition to traditional outcome measures. Tibial components placed in constitutional varus in this study demonstrated excellent patient satisfaction and improvement in knee function following TKA.