Reference values for metacarpophalangeal joint stiffness in normals

Area of Science:

• Biomedical Engineering
• Orthopedics
• Biomechanics

Background:

• Joint stiffness is a key indicator of hand function.
• Accurate measurement of joint stiffness is crucial for diagnosis and treatment.
• Existing methods may lack precision or ease of use.

Purpose of the Study:

• To describe a new microprocessor-controlled arthrograph for measuring finger joint stiffness.
• To establish reference limits for stiffness in normal subjects.
• To evaluate factors influencing measurement precision.

Main Methods:

• Development of a microprocessor-controlled arthrograph.
• Measurement of metacarpophalangeal joint stiffness in index, middle, and ring fingers.
• Inclusion of finger circumference, age, and sex in precision analysis.

Main Results:

• The apparatus provides simple, quick, and reproducible stiffness measurements.
• Reference limits for right middle finger stiffness were determined in 128 normal subjects.
• Finger circumference significantly enhanced measurement precision.

Conclusions:

• The new arthrograph is a reliable tool for assessing finger joint stiffness.
• Finger circumference is a critical factor for precise stiffness measurements.
• Age and sex do not further enhance precision beyond finger circumference.