Uncemented acetabular cups in dysplastic and protrusio acetabuli

Area of Science:

• Orthopedic surgery
• Biomaterials science
• Radiology

Background:

• Acetabular dysplasia and protrusio present unique challenges in total hip arthroplasty.
• The Ring uncemented polyethylene to metal system is utilized for these complex cases.
• Assessing implant stability and long-term radiographic changes is crucial.

Purpose of the Study:

• To evaluate the outcomes of total hip arthroplasty using the Ring uncemented system in hips with acetabular protrusio or dysplasia.
• To assess the stability and function of the acetabular implant.
• To analyze radiologic changes in the medial acetabular wall in protrusio cases.

Main Methods:

• Retrospective analysis of 84 total hip arthroplasties.
• Utilized the Ring uncemented polyethylene to metal system.
• Follow-up period of two to five years with annual assessments.

Main Results:

• All patients achieved excellent functional results post-operation.
• Six of eight severe protrusio hips showed increased medial acetabular wall thickness at one year.
• Adequate stability and function were observed in dysplastic hips despite limited bony cover.

Conclusions:

• The Ring uncemented system provides excellent functional outcomes for total hip arthroplasty in hips with acetabular dysplasia or protrusio.
• Positive radiographic remodeling of the medial acetabular wall occurs in protrusio cases.
• Acetabular implant stability is not compromised by limited lateral bony cover in dysplastic hips.