Type III acetabular defect revision with bilobed components: five-year results.

Area of Science:

• Orthopaedic Surgery
• Biomaterials Engineering

Background:

• Acetabular deficiencies, particularly combined segmental and cavitary (American Academy of Orthopaedic Surgeons Type III), present significant challenges in revision hip arthroplasty.
• Increasing frequency of these complex defects necessitates advanced reconstructive solutions.

Purpose of the Study:

• To evaluate the clinical and radiographic outcomes of using porous-coated bilobed acetabular components for treating American Academy of Orthopaedic Surgeons Type III acetabular deficiencies.
• To assess the efficacy of this implant in restoring hip center and function without structural bone grafting.

Main Methods:

• A prospective study involving 11 consecutive patients with Type III acetabular defects.
• Revision arthroplasty was performed using porous-coated bilobed cups without structural bone graft.
• Patients were followed prospectively, with clinical (Harris hip score) and radiographic assessments.

Main Results:

• Significant improvement in average Harris hip scores from 36 preoperatively to 85 postoperatively.
• Radiographic analysis demonstrated restoration of the hip center and decreased leg length discrepancies (34 mm to 7 mm).
• No patients required re-operation or planned further revision at intermediate follow-up.

Conclusions:

• Porous-coated bilobed acetabular components provide favorable intermediate-term clinical and radiographic results for Type III acetabular defects.
• This implant is a viable reconstructive option, maximizing bone-implant contact and restoring native hip center without bone grafting or cement.