[Modular revision systems in total knee arthroplasty. Possibilities and techniques]

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Revision total knee arthroplasty (TKA) presents complex challenges.
• Addressing bone defects and ligamentous instability is crucial for successful revision TKA.

Purpose of the Study:

• To describe surgical techniques for revision TKA using modular revision systems.
• To demonstrate the capabilities of modern revision systems in reconstructing bone defects and ligament instabilities.

Main Methods:

• Exploration of the knee joint, implant removal, and implantation of modular revision systems.
• Utilizing a three-step technique for implant insertion.
• Employing modular stems for diaphyseal load transfer.

Main Results:

• Modular systems enable adaptation to individual bone quality, defects, and soft tissue conditions.
• Metal wedges and blocks are used for reconstructing uncontained bone defects.
• A range of prosthetic constraints, from cruciate-retaining to fully constrained hinges, addresses varying degrees of instability.

Conclusions:

• Modular revision knee systems offer versatile solutions for complex revision TKA.
• Least constrained prostheses should be used when possible, reserving fully constrained hinges for extreme cases.
• Literature review supports the efficacy of modular revision systems.