Dual Mobility Acetabular Cup Utilization in Total Hip Arthroplasty: Mitigating Instability Risks

Area of Science:

• Orthopedic Surgery
• Biomaterials Engineering
• Clinical Outcomes Research

Background:

• Total hip arthroplasty (THA) complications, including dislocation, are rising with increased life expectancy and procedure rates.
• Dislocation is the primary cause of revision surgery within the first year post-THA.
• High-risk patients require specialized implants to mitigate instability.

Purpose of the Study:

• To evaluate the efficacy of dual mobility cups (DMC) in reducing hip instability in high-risk THA patients.
• To assess complication rates and functional outcomes associated with DMC implantation in a challenging patient cohort.
• To compare DMC performance against standard implants in preventing dislocation.

Main Methods:

• Retrospective review of 163 patients (168 hips) undergoing THA with DMC from 2014-2021.
• DMC implantation in patients with neuromuscular diseases or femoral neck fractures (FNF).
• Analysis of clinical outcomes, instability, and complications using SPSS, with chi-squared and t-tests for statistical comparison.

Main Results:

• Mean follow-up of 48 months in 163 patients (mean age 58 years).
• No dislocations requiring revision occurred; one case of intraprosthetic dislocation without metal head dislocation was revised.
• Significant improvement in Harris Hip Score (HHS) from 49 preoperatively to 89 postoperatively at four years.

Conclusions:

• Dual mobility cups (DMC) effectively reduce dislocation rates in high-risk THA patients, including those with FNF.
• DMC implantation leads to improved patient satisfaction and near-normal functional restoration.
• Greater consideration of DMC is recommended for patients identified as at high risk for dislocation.