Abstract
Introduction:
Patient Satisfaction after Arthroplasty is being considered as a priority outcome and an important addition to traditional outcome measures. The reported satisfaction rate in the literature is disappointing (75%–89%). Traditional techniques for TKA have made neutral (0° ±3°) coronal alignment a primary technical goal. We present the results of “Ideal Arthroplasty Kinematics” ie a perfectly balanced knee irrespective of mechanical alignment.
Materials and Methods:
The primary technical goal was to achieved tensiometer controlled balance, within 2 degrees, of medial and lateral soft tissues throughout range of motion, and equal gap sizes within 2 mm. 864 (92.9%) of 914 patients, operated by one surgeon, between January 2007 and December 2012 were prospectively followed for an average of 40.4 months. They were asked if they were satisfied, unsatisfied or unsure by an independent research-nursing sister. Unsure patients were categorized as unsatisfied. 817 (94.5%) of this group had satisfactory postoperative long leg x-rays as per Paley's technique. The patient satisfaction was correlated to post-operative mechanical axis (M.A.)
Results:
803 (92.9%) of the patients were satisfied with their knees. 719 (88%) had a M.A. within ±3° of neutral; so called “Aligned” knees. 98 (12%) had a M.A. >3°; so called “Outliers”. Patients with aligned knees had a 92.4% satisfaction rate and those that were outliers were satisfied 92.9% of the time.
Conclusion:
By attempting to achieve “Ideal Arthroplasty Kinematics” – ensuring the medial and lateral soft tissues are balanced within a couple of degrees using a tensiometer better patient satisfaction has been achieved than previously reported.
Knee alignment did not affect satisfaction rate. It seems it is better to leave constitutionally varus patients in varus and similarly valgus patients in valgus
