The efficiency of patient-specific instrumentation and technological assistance in cementless total hip arthroplasty via the direct anterior approach.

Background: Patient-specific instrumentation for total hip arthroplasty (PSI-THA) is an emerging technology that improves the accuracy of femoral neck osteotomy and implant positioning. Unlike conventional 2D radiograph-based planning, PSI-THA leverages 3D CT reconstructions for personalized, technology-assisted positioning. This study sought to assess the intraoperative efficiency of PSI-THA in terms of surgery duration and blood loss by comparing PSI incorporating image-based guides and 3D planning with conventional surgery and 2D planning for cementless THA performed via the direct anterior approach (DAA).

Methods: Two consecutive cohorts of 100 patients each were retrospectively analysed. All patients underwent cementless THA with a straight quadrangular stem and a ceramic-on-ceramic head and liners. Two-dimensional templating was performed for the first cohort, whereas a 3D template with CT-based PSI for femoral neck osteotomy and acetabular cup positioning was performed for the second cohort. A laser guidance system was employed to increase implant placement accuracy. Operating time and intraoperative blood loss were compared between the groups.

Results: The demographic characteristics of the two groups were comparable. The average operating time was 45.7 min (SD: 16.11) in the conventional group and 31.9 min (SD: 9.92) in the PSI group (p < 0.001). Blood loss was also significantly lower in the PSI group (319 ml) than in the conventional group (407 ml; p < 0.017).

Conclusions: Compared with conventional planning, PSI with 3D planning and technological assistance significantly reduced the operating time by an average of over 10 min as well as the amount of blood loss. The improved planning and execution accuracy of PSI minimizes the need for intraoperative adjustments, improves confidence in implant positioning, and reduces the need for compromises and the identification of multiple landmarks, underscoring the value of this planning technology in DAA THA.

Clinical Trial Number: Not applicable.