Acetabulum Cup Alignment with and Without Guide in Total Hip Replacement

Introduction: Successful total hip replacement (THR) depends on the precise concentricity of acetabular cups. Malposition may cause dislocation, impingement, early loosening, and revision surgery. In the resource-constrained environment, the accuracy of alignment becomes difficult to achieve, particularly using the freehand technique. Alignment guide use can be a potentially inexpensive solution to improve accuracy and reduce complications. Objective: To compare the accuracy of acetabular cup placement in total hip arthroplasty with and without the use of mechanical alignment guides at Department of Orthopedics, CMH Rawalpindi, Pakistan. Material and Method: This comparative prospective study involved 60 participants and conducted at Department of Orthopedics, CMH Rawalpindi, Pakistan, who underwent unilateral primary THR from August, 2024 to January, 2025. The patients were split into two groups. Group A (n=30) was operated under guided cup insertion, and Group B (n=30) under freehand insertion. The radiographs taken after the surgery were measured using inclination and anteversion angles, and the placement was assessed according to the safe zone of Lewinnek angles. Results: Guide-assisted placement led to much better alignment. The average inclination angle and anteversion angle in Group A were 42.6 degrees +/-4.3 degrees and 17.1 degrees +/-3.9 degrees, respectively, as compared to Group B, whose average was 47.3 degrees +/-6.1 degrees and 22.8 degrees +/-5.4 degrees, respectively (p<0.01). The compliance with the safe zone was 86.7 per cent in Group A as compared to 56.7 percent in Group B (p=0.009). There was a slight difference in operative time in Group A, which was not significant. Conclusion: The probability of being ascribed to predicting acetabular cup placement using alignment guides in THR significantly increases. Simple guide systems may be incorporated into working practice in low-resource environments, where they could improve surgical accuracy and decrease the likelihood of postoperative complications.