Smartphone Application Helps Improve the Accuracy of Cup Placement by Young, Less-Experienced Surgeons during Primary Total Hip Arthroplasty

Document Type : RESEARCH PAPER


1 Orthopaedic Department, Qena Faculty of Medicine and University Hospital, South Valley University, Qena, Egypt

2 Orthopaedic and Traumatology Department, Assiut University Hospital, Assiut, Egypt

3 Knee & Orthopaedic Clinic, Powai, Mumbai Head of Research, AIMD Research


Background: Dislocation after total hip arthroplasty (THA) partly under the surgeon’s control, by appropriate placement 
of the components. We aimed in this study to determine the accuracy of using intra-operative smartphone applications 
(Apps) to place the acetabular cup within the safe abduction angle by less experienced surgeons during THA surgery 
when compared to the conventional freehand technique for cup placement.
Methods: Sixty primary THAs were performed, 30 using the conventional freehand technique (control group) and 30 
using the smartphone app technique (study group) to determine the acetabular cup abduction angle by the same young 
surgeon with less than one year of experience. Postoperative mean cup abduction angle, mean cup anteversion angle, 
and the percentage of cups within the safe abduction zone as measured on radiographs were compared between the 
two groups.
Results: In the study group, the mean cup abduction angle was significantly lower (P=0.0008), and the acetabular 
cup was placed within the safe zone in a significantly higher (P<0.001) percentage of patients (93% vs 63%) when 
compared to the control group. However, there was no significant difference (P=0.40) between the two groups when 
the mean cup anteversion angle was compared.
Conclusion: The smartphone app technique may help achieve an accurate acetabular cup abduction angle and a 
higher percentage of cups placed within the safe zone of abduction by a less experienced surgeon when compared to 
the conventional freehand technique. Using tools such as the smartphone app to measure the acetabular cup position
can reduce intraoperative errors by young and less experienced surgeons during THA surgery.
Level of evidence: IV


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