Abstract
Introduction
The KneeAlign2 (OrthAlign, Inc., Aliso Viejo, CA) is a portable accelerometer-based navigation device for use in performing the distal femoral resection in total knee arthroplasty (TKA). This device works as a computer-assisted surgical system. It does not require the use of a large console for registration and alignment feedback.(image1,2)
Purpose
The aim of this study was to investigate the accuracy in positioning the femoral component and the presense of a learning curve in conducting TKA using this device.
Materials and methods
From May 2015 to March 2016, 60 knees underwent a primary TKA using a portable accelerometer-based navigation device for performing the distal femoral resection. These TKAs were devided in two groups. Group1: operated by surgeon of experience using the KneeAlign2 more than 30 cases. Group2: operated by surgeons of experience using the KneeAlign2 less than 30 cases. Standing AP hip-to-ankle radiographs were obtained postoperatively. Positioning of the femoral component was measured by the radiographs. Outlier in coronal alignment were defined as >3°. The radiographic results and operation time were compared between the groups. Students t-test was performed to assess the statistical analysis (p<0.05)
Result
There was no outlier and all patients had an alignment within 90±3°to the femoral mechanical axis in the coronal plane in both groups. The mean deviation(absolute values) from the neutral alignment of the femoral component were 1.5±0.5 in group1 and1.2±0.7 in group2. There was no statistical significance between the groups. Average operation time was 106.2 minutes in group1 and 108.5 minutes in group2. There was no statistical significance between the groups. There were no complications during the surgery associated with the navigation device.
Conclusion
This portable navigation device is highly accurate in positioning the femoral component in TKA. And as the learning curve for using this device does not be observed, this portable navigation is easy to handle even for beginner users.
For any figures or tables, please contact authors directly (see Info & Metrics tab above).
