Use of iPhone technology in improving acetabular component position in total hip arthroplasty

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

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.

Evaluation of Usability, Perception of Usefulness, and Efficiency of an Application in Interpreting Imaging Examinations and Supporting Decision-Making in Orthopedics

Background: Medical smartphone applications have rendered positive results in daily practice and also serve as potentially valuable educational tools. In orthopedics, radiograph analysis and angle measurements comprise an essential mechanism in the diagnosis, treatment, planning, and evaluation of the results in orthopedic surgery. Purpose: Thus, the present study aimed to evaluate an application for mobile devices for orthopedic doctors and orthopedic residents. The application proposes the analysis and interpretation of radiographic imaging examinations through assessments and angle measurements. In this survey, we analyzed the parameter usability and usefulness of a mobile application for the iOS system, in addition to conducting its validation. Patients and Methods: The application was tested by 26 volunteers: 13 orthopedists and 13 orthopedic residents. Results: After applying the System Utility Score (SUS) questionnaire, which assesses the usability of an application, a score of 84.5 was obtained, a value that represents an A+ rating on the Sauro and Lewis scale. There was no statistically significant difference when comparing the SUS between the orthopedic residents and orthopedists. According to the usefulness perception analysis, 90% of the residents responded positively to the questions, while among orthopedists, the percentage was 75%, denoting a statistically significant difference (p = 0.002). Subsequently, the application underwent validation to assess whether the calculated angle measurements were reliable when compared with those obtained using the goniometer. No significant differences were observed when comparing the angles measured by the two evaluated methods. Conclusion/Clinical Relevance: In conclusion, the developed application can reliably contribute to the measurement of angles in radiographs, assisting in therapeutic decision-making, and may be used as an instrument to promote the teaching and learning processes in orthopedics.

3D Printed Patient-Specific Acetabular Jig for Cup Placement in Total Hip Arthroplasty

INTRODUCTION

Acetabular cup placement is an important modifiable factor determining complication rates like aseptic loosening and hip dislocation related to faulty cup placement, which by standard method is largely dependent upon eyeballing and surgeon's judgment. We evaluated a self-designed, low-cost, patient-specific acetabular jig to guide cup placement in total hip arthroplasty in comparison to conventional technique.

METHODS

It was a prospective randomized control study. Thirty-six patients were categorized into group-A & group-B. In group-A, virtually designed acetabular jig was 3 Dimensional (3D) printed and used intra-operatively to guide cup placement. In group-B, the standard method of cup placement was used. Acetabular cup placement was evaluated on post-operative x-rays and compared between two groups.

RESULTS

In group-A, angle of anteversion were significantly in centre of range of safe zone as compared to group B in which hip is maximally stable with more precision in creating hip centre as compared to group-B without any significant(p = 0.325) increase in surgical time or blood loss.

CONCLUSION

Computed tomography (CT) scan based virtual pre-operative templating and cup placement guided by virtually designed, patient-specific acetabular jig is a low-cost tool with a short learning curve which can be designed and made available easily. It is a useful tool in decreasing chances of malpositioning of cup and recreates hip centre close to anatomical one especially in cases where anatomy has been distorted such as bony ankylosis and developmental dysplasia of hip.