Variable angle locking intercarpal fusion system for four-corner arthrodesis: indications and surgical technique

Area of Science:

• Orthopedic Surgery
• Hand and Wrist Surgery
• Biomedical Engineering

Background:

• Four-corner fusion (4CF) is a standard procedure for posttraumatic wrist degeneration.
• Achieving rapid, solid bone union without hardware complications in 4CF remains a challenge.
• Existing implants for 4CF have reported issues, necessitating improved techniques.

Purpose of the Study:

• To present a novel implant system and surgical technique for four-corner fusion (4CF).
• To ensure precise positioning, firm fixation, and solid bone union at the midcarpal joint.
• To facilitate early postoperative recovery and minimize hardware-related complications.

Main Methods:

• Development of a circular plate with variable angle locking and compression screws.
• Design of a reaming-distraction-compression guide for plate positioning and joint preparation.
• Surgical technique utilizing the new implant system for 4CF, including bone grafting.

Main Results:

• The described implant system provides a very solid construct due to locking technology.
• The technique allows for precise fixation and firm attachment to carpal bones.
• The specialized guide facilitates debridement and bone graft interposition for enhanced fusion.

Conclusions:

• The novel circular plate system offers a precise and effective method for four-corner fusion (4CF).
• This system aims to achieve rapid solid bone union and improve patient outcomes in wrist fusion.
• The described technique and implant potentially overcome limitations of previous 4CF hardware.