[Impact of a simulated DIPJ Arthrodesis on Movement and Force Patterns]

Area of Science:

• Orthopedics
• Biomechanics
• Hand Surgery

Background:

• Distal interphalangeal joint (DIPJ) arthrodesis is a common surgical procedure for treating osteoarthritis.
• The interconnected nature of the hand's muscle-tendon units suggests that DIPJ arthrodesis may influence overall finger motion and force transmission.
• Previous research has lacked real-time quantitative analysis of these biomechanical effects.

Purpose of the Study:

• To quantitatively analyze the real-time effects of simulated DIPJ arthrodesis on finger motion and force development during grasping.
• To investigate the dynamic interactions between finger joints and force patterns in individual finger rays.

Main Methods:

• Nineteen healthy volunteers participated in the study.
• A Technische Universität Berlin (TUB) sensor glove was used to dynamically measure finger motion and force during simulated DIPJ arthrodesis.
• Participants performed fist closure and two types of force grips, compared against physiological conditions.

Main Results:

• Simulated DIPJ arthrodesis led to decreased flexion in the proximal interphalangeal joint (PIPJ) and increased flexion in the metacarpophalangeal joint (MPJ) during fist closure.
• During force grips, simulated DIPJ arthrodesis resulted in increased MPJ flexion and decreased PIPJ flexion.
• Averaged force reduction across all fingers was minimal, not exceeding 1.4%.

Conclusions:

• This study provides the first quantitative, real-time analysis of grasping with simulated DIPJ arthrodesis.
• The findings highlight the dynamic interplay between finger joints and demonstrate subtle alterations in force distribution.
• The results offer valuable insights into the biomechanical consequences of DIPJ arthrodesis on hand function.