A Novel Acetabular Biplanar Calibration Method for Establishing Hip Arthroscopic Portals

OBJECTIVE: To introduce a novel acetabular biplanar calibration (ABC) method to improve the accuracy of hip arthroscopic portal establishment. STUDY DESIGN: An observational study. Place and Duration of the Study: Department of Orthopaedic Surgery, Chongqing Orthopaedic Hospital of Traditional Chinese Medicine, Chongqing, China, from January to December 2024. METHODOLOGY: This study included patients with femoroacetabular impingement syndrome or acetabular labral tear. Pelvic morphology was measured from preoperative radiographs. The ABC method involved placing metallic markers on the coronal (Landmark A) and sagittal (Landmark B) planes around the operative hip and measuring the distances from the anterior superior iliac spine (ASIS) to the two markers. The establishment of anterolateral (AL), mid-anterior (MA), and distal anterolateral accessory (DALA) portals was based on the above landmarks and confirmed by fluoroscopy. The accuracy rates of these portal placements were calculated as percentages, respectively. RESULTS: A total of nine patients were included. The puncture target on the coronal plane was 3.06 ± 0.39 cm distal and 2.97 ± 0.42 cm medial to the ASIS. The puncture target on the sagittal plane was 2.88 ± 0.38 cm distal and 8.13 ± 1.25 cm lateral to the ASIS. The accuracy rates of establishing the AL, MA, and DALA portals using the ABC method were 77.8% (7/9), 88.9% (8/9), and 77.8% (7/9), respectively. CONCLUSION: The ABC method appears to be a promising avenue for improving the accuracy of hip arthroscopic portal-establishment, with reduced reliance on femoral positioning. It can also be used for frequent arthroscopic instrument navigation. Future research with larger samples, multicentre studies, and the integration of advanced imaging technologies is needed to validate its reliability and effectiveness fully. KEY WORDS: Hip arthroplasty, Landmark, Portal establishment.