Biomechanical characteristics of suture techniques in extensor zone IV

Area of Science:

• Orthopedic Surgery
• Biomechanics
• Hand Tendon Injuries

Background:

• Zone IV extensor tendon injuries over the proximal phalanx present unique challenges in surgical repair.
• Understanding biomechanical parameters is crucial for optimizing functional outcomes after extensor tendon repair.

Purpose of the Study:

• To investigate biomechanical parameters of different suture techniques for extensor tendon repair in Zone IV.
• To evaluate tendon shortening and joint range of motion following various repair methods.
• To assess the potential for early controlled range of motion after extensor tendon repair.

Main Methods:

• Comparison of biomechanical parameters for typical suture techniques, Kleinert modification of the Bunnell technique, and modified Kessler technique.
• Assessment of tendon length changes post-suture.
• Measurement of flexion at the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints.

Main Results:

• Typical suture techniques resulted in insignificant tendon shortening.
• No significant loss of flexion was observed at the MCP or PIP joints with typical techniques.
• The Kleinert modification and modified Kessler technique demonstrated superior strength and potential for physiological tolerance of early motion.

Conclusions:

• Modified Kessler and Kleinert techniques appear to be the strongest for Zone IV extensor tendon repair.
• Repaired extensor tendons may tolerate controlled, short-arc dynamic or active range of motion.
• Further research into controlled rehabilitation protocols for extensor tendon injuries is warranted.