Morphological Changes in Flexor Tendon Adhesion Following Early Exercise After Tendon Repair

Area of Science:

• Orthopedic Surgery
• Regenerative Medicine
• Biomedical Engineering

Background:

• Adhesions are a frequent complication after flexor tendon surgery, impeding tendon gliding.
• Developing effective strategies to mitigate adhesion formation is crucial for successful surgical outcomes.

Purpose of the Study:

• To investigate the impact of early active exercise on the development and characteristics of flexor tendon adhesions.
• To determine the optimal timing for initiating exercise to promote favorable adhesion remodeling.

Main Methods:

• A surgical adhesion model was created in White Leghorn chickens by incising and crushing the flexor digitorum profundus tendon sheath.
• Tendon repair sites were immobilized for 1, 2, or 3 weeks, followed by 1, 2, or 3 weeks of active exercise.
• Morphological assessment of adhesions and evaluation of tendon gliding were performed post-exercise.

Main Results:

• Early exercise (within 2 weeks of repair) led to the formation of elastic, mesotenon-like adhesions that did not restrict tendon gliding.
• Delayed exercise (initiated at 3 weeks) resulted in mature, inelastic adhesions that significantly inhibited tendon gliding.
• The elasticity and gliding potential of adhesions were dependent on the timing of exercise initiation.

Conclusions:

• Initiating active exercise within two weeks post-flexor tendon repair promotes the formation of elastic adhesions, enhancing tendon gliding.
• Delaying exercise initiation beyond three weeks leads to mature adhesions that are resistant to remodeling and continue to restrict tendon function.