The Ring uncemented plastic-on-metal total hip replacement. Five-year results

Area of Science:

• Orthopedic Surgery
• Biomaterials Science
• Medical Device Engineering

Background:

• The Ring prosthesis aimed to merge benefits of cemented and cementless total hip replacements.
• Plastic-on-metal articulation was utilized in this design.

Purpose of the Study:

• To evaluate the clinical outcomes and performance of the Ring plastic-on-metal total hip replacement.
• To assess the long-term efficacy and safety of this implant system.

Main Methods:

• Review of 1488 Ring total hip replacement procedures.
• Follow-up ranging from two to seven years, with a subgroup completing at least five years.
• Clinical results graded using the Charnley scale for pain, function, and range of movement.

Main Results:

• Excellent clinical results reported in 93% of the total series and 87% of the five-year follow-up group.
• Favorable Charnley scale scores: 5.86 for pain, 5.96 for function, and 5.9 for range of movement.
• Zero deep infection rate and a 1.5% revision rate for the entire series; erosive issues noted with smaller acetabular components.

Conclusions:

• The Ring total hip replacement demonstrates high success rates and favorable clinical outcomes.
• The implant system shows a low complication profile, including zero deep infections.
• Further investigation into erosive problems with smaller acetabular components is warranted, though component exchange remains feasible.