Differences in the Outcomes of Early Active Mobilization Following Flexor Tendon Repair Between Zone 1 and Distal...

Area of Science:

• Orthopedic Surgery
• Hand Surgery
• Reconstructive Surgery

Background:

• Complete A4 pulley release aids flexor tendon repair and excursion.
• Optimal repair levels for flexor digitorum profundus injuries with A4 pulley release remain unclear.
• Early active mobilization is crucial for functional recovery after tendon repair.

Purpose of the Study:

• To compare active range of motion in finger joints after flexor digitorum profundus tendon repair at zone 1 versus zone 2A.
• To evaluate outcomes of zone 1 and zone 2A flexor tendon injuries treated with a six-strand suture and complete A4 pulley release.
• To assess the impact of injury level on functional recovery following early active mobilization.

Main Methods:

• Retrospective case series of 27 fingers (22 patients) with zone 1 (13) or zone 2A (14) flexor digitorum profundus injuries.
• All tendons repaired using a six-strand suture (Yoshizu #1 technique) with complete A4 pulley release.
• Early active mobilization initiated within three weeks post-surgery, with an average follow-up of 7 months.

Main Results:

• No tendon bowstringing observed.
• One rupture of a zone 1 flexor tendon repair occurred 8 weeks post-surgery.
• Excluding the rupture, no significant differences in overall active range of motion between zone 1 and 2A injuries were found.
• Zone 1 injuries showed significantly reduced distal interphalangeal joint motion and increased total extension deficit compared to zone 2A.

Conclusions:

• Despite consistent surgical technique and rehabilitation, zone 1 flexor tendon injuries resulted in poorer distal interphalangeal joint motion and greater extension deficits compared to zone 2A injuries.
• Complete A4 pulley release and early mobilization may not fully restore distal interphalangeal joint function in zone 1 injuries.
• Further investigation is needed to optimize outcomes for zone 1 flexor tendon repairs.