Using Imageless Optical Navigation to Identify the New Hip Center in Crowe IV Dysplasia

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Medical Navigation Technology

Background:

• Acetabular dysplasia presents challenges in total hip arthroplasty (THA), particularly in accurately identifying the native acetabulum for optimal cup placement.
• Crowe IV hip dysplasia involves significant anatomical distortion, making precise surgical planning and execution difficult.
• Accurate component positioning is crucial for restoring hip biomechanics and achieving long-term implant survival.

Observation:

• A case of Crowe IV hip dysplasia successfully treated with THA using 3-dimensional mini-optical navigation.
• The navigation system facilitated matching the new hip center to the preoperative plan, identifying the true acetabulum 34 mm inferior to the pseudoacetabulum.
• This approach allowed for precise titration of femoral shortening (20 mm) to achieve a final limb length discrepancy of 14 mm.

Findings:

• This is the first reported use of imageless optical navigation in the context of severe acetabular dysplasia (Crowe IV).
• The imageless navigation system demonstrated a small spatial footprint and did not require preoperative axial imaging or multipoint bone surface registration.
• The technology enabled accurate cup positioning and guided the subsequent femoral shortening, crucial for reconstructing the dysplastic hip.

Implications:

• Imageless optical navigation offers a valuable tool for surgeons performing THA in patients with complex acetabular dysplasia.
• This technology can improve the accuracy of acetabular component placement and facilitate limb length equalization in challenging cases.
• Further investigation into the broader application of imageless navigation in hip reconstruction surgery is warranted.