Once upon a time.... Dual mobility: history

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Sir John Charnley's low friction arthroplasty (since 1962) offered good long-term results but dislocation remained a significant complication.
• Dislocation in total hip arthroplasty (THA) is a cumulative risk throughout the patient's and prosthesis's lifespan.
• The concept of dual mobility was introduced in the 1970s to address dislocation forces.

Observation:

• The first dual mobility cup, NOVAE (1979), incorporated two articulations to increase jump distance and reduce dislocation forces.
• The "third articulation," a metal/polyethylene bearing, was described in 2003.
• Numerous dual mobility cup designs with varied fixation methods have been developed since 1996.

Findings:

• Third-generation dual mobility cups demonstrate excellent outcomes with over ten years of follow-up.
• Dislocation rates are consistently low, ranging from 1% to 2% in primary, revision, and recurrent THA cases.
• These cups are effective in managing THA following femoral neck fractures.

Implications:

• Dual mobility technology offers a viable solution to mitigate a major complication in THA.
• The continued development and application of dual mobility cups can improve patient outcomes and prosthesis longevity.
• This approach holds promise for complex THA cases, including revisions and fracture management.