Abstract
Introduction
Aim of this study is to assess any differences in digital templanting accuracy of a modular short femoral stems implanted with 2 different appoaches (direct anterior and posterolateral).
Material and Methods
From December 2012 to Jenaury 2014 100 patient undergoing to a THA using the same implant with a short femoral modular stem were prospectively included in the study and divided in 2 groups according to the surgical approach. All the patients underwent to the same preoperative radiological protocol and the digital templating. The digital templating results were compared with the truly inserted implant size and a statistical analysis was carried on.
Results
For the cup the mean percentage of agreement (±2 size) was 90.0 % in Anterior approach-group and 89.6 % in the the posterolateral approach group. For the mean percentage of agreement (± 2 size) was 88.0 % in and 89.1 % respectively. Likewise there was a statistical significant better accuracy in the modular femoral neck accuracy in the anterior approach (±2 size) and a statistical significant higher percentage of modular femoral neck with an increased antiversion in the posterolateral approach.
Discussion
In our experience digital templating in short modular femoral stem seems to be less accurate for the posterior-lateral approach in term of both femoral neck length and antiversion. A possible explanation may be not a technical error but just a surgeon behavior to overcorrect the templating to prevent dislocation potentially more common using a postero-lateral approach
