“ Factors affecting demonstration of intra-operative Co-planar test in Total Hip Arthoplasty ”

Volume 6 | Issue 1 | Jan-April 2018 | Page 35-38 | Sharath Ramantha Kittanakere, Ramneesh Kohli, Harsha Mohan Shah, Naresh Shetty, Rahul P Bhonsle, Archadhaa Sivakanthan

Authors: Sharath Ramantha Kittanakere [1], Ramneesh Kohli [1], Harsha Mohan Shah [1], Naresh Shetty [1], Rahul P Bhonsle [1], Archadhaa Sivakanthan [1].

[1]Department Of orthopaedics, Ramaiah Medical college, Bangalore.

Address of Correspondence
Dr. Kittanakere Ramanatha Sharath
87,3A Cross , Annapurna Enclave, Katriguppe main Road , BSK 3 Stage, Bangalore -85
Email :


Context: Coplanar test measures intraoperative value of combined anteversion of femoral and acetabular components .
Aim: Purpose of this study was to investigate factors affecting demonstration of Coplanar test when the combined anteversion (CA) was be kept within the safe zone in uncemented total hip arthroplasty (THA) in posterior approach .
Settings and Design: It’s a prospective study design conducted in a teritiary care health centre.
Methods and Material: We analysed 80 cases of primary uncemented THA between October 2015 to Dec 2016 . Pre-operatively, we measured height of all patients and mid –thigh circumference .Transverse acetabular ligament was used as a reference for acetabular anteversion and implantation . We were able to demonstrate the coplanar test in 58 patients . Analysis of correlation of coplanar test with thigh circumference , height of the patient , Neck shaft angle of femoral stem and abduction angle of acetabular component was done .
Statistical analysis used: Baseline Data were described in mean and Interquartile Ratio compared to non parametric test. Pearson chi square test for correlation of abduction angle and neck shaft angle with coplanar test. Levene test for correlation of thigh circumference and height of the patient. Multiple logistic regression analysis for all factors .
Results: Inclination of cup and thigh circumference were statistically significant independent factors which could affect the test demonstration .
Keywords: Co-planar test , Combined anteversion , uncemented total hip replacement , Ranawat coplanar test.


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How to Cite this article: Kittanakere SR, Kohli R, Shah HM, Shetty N, Bhonsle RP, Sivakanthan A. Factors affecting demonstration of intra-operative Co-planar test in Total Hip Arthoplasty. J Kar Orth Assoc. Jan-April 2018; 6(1): 35-38

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