A new total distal radioulnar joint prosthesis: functional outcome

Area of Science:

• Orthopedic surgery
• Biomaterials science
• Reconstructive surgery

Background:

• Distal radioulnar joint (DRUJ) instability often results from failed reconstructive procedures or trauma.
• Current treatment options for DRUJ instability may involve resection, leading to functional deficits.
• A novel prosthesis design aims to restore stability and function after distal ulnar resection.

Purpose of the Study:

• To detail the design evolution of a novel 2-part DRUJ prosthesis with hydroxyapatite coating for bony fixation.
• To assess the short-term functional outcomes and clinical effectiveness of this DRUJ prosthesis.

Main Methods:

• Nineteen patients with DRUJ instability underwent prosthesis implantation.
• Prostheses were implanted following failed Darrach or Sauvé-Kapandji procedures, trauma, or synovitis.
• Functional outcomes including range of motion, grip strength, and pain were evaluated using validated questionnaires and measurements.

Main Results:

• Significant improvements were observed in forearm pronation (79° to 88°) and grip strength (10 kg to 16 kg).
• Patient-reported pain decreased significantly (Visual Analog Scale 5.3 to 3.5).
• The distal ulna remained clinically stable in 12 patients retaining the prosthesis.

Conclusions:

• An earlier prototype demonstrated a high failure rate due to loosening.
• The current DRUJ prosthesis prototype shows promising early clinical improvements.
• This prosthesis represents a potential new treatment for ulnar instability following distal ulnar resection.