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03 / Plastic & Reconstructive Surgery · open

Flexor tendon repair

Rejoining a cut flexor tendon inside its tight fibrous tunnel, then the paradox: a repair that must be strong enough to move on day one, because stillness is what ruins it.

Indication: Flexor tendon division in the hand or wrist; classically a knife or glass across the flexor surface.

Part of Plastic & Reconstructive Surgery →4 stages1 complications to knowopen
A closed wound: what a hand repair looks like from the surface
Wikip2011 · CC BY-SA 3.0

On the tray for this operation

Test yourself on the tray

Stage

1 / 4

Exploration

The wound is extended along Bruner zigzag lines under tourniquet, and both tendon ends retrieved, the proximal end often having recoiled up the palm.

🔧 Scalpel🔧 Adson forceps🔧 Mosquito clamp

Watch for: Missed digital nerve injury alongside the tendon · Trauma to the ends from rough retrieval

Why are we operating?

Flexor tendon repair restores the cables that bend the fingers: divided tendons do not heal into function by themselves, and in zone II both flexors travel through an unforgiving fibro-osseous tunnel where scar welds tendon to sheath. The operation is a strong, low-friction repair; the outcome is decided equally by the hand therapy that follows, because a repair that does not glide is a repair that failed politely.

Pulls toward surgery

Divided flexor tendons with lost active flexionSharp injuries suited to primary repair within daysAssociated nerve and vessel injury repaired in the same sittingA patient able to engage with months of therapy

Gives the team pause

Sepsis in the sheath (drain first, repair later)Segmental loss and late presentation (staged reconstruction's territory)Rehabilitation that cannot realistically happen

What the surgeon is thinking

  • Exploration

    Why is the wound extended before anything is repaired?

    The skin wound is a keyhole over a crime scene: tendon ends retract, and the injury's true level depends on where the fingers were at the moment of cutting. Bruner zig-zag extensions open the sheath's territory without crossing flexion creases at right angles, converting a guess into an exposure.

  • Assessing the zone

    What makes zone II historically 'no man's land'?

    Both tendons share a tight synovial tunnel under the pulley system: any repair bulk or scar tethers them to each other and the sheath, and early repairs failed so often the zone earned its nickname. Modern technique reclaimed it, but only by respecting exactly why it was lost: glide is the currency.

  • The repair

    What does the core suture's architecture actually determine?

    The repair's strength budget, which is what the rehabilitation protocol spends: multi-strand core repairs with a tidy epitendinous finish are strong enough for early motion, and the epitendinous layer also smooths the glide surface. Strand count, grip in the tendon and low bulk are the three levers.

  • Closure and early protected motion

    Why is the splint-and-therapy plan part of the operation?

    Because immobilised repairs weld to the sheath and early uncontrolled motion ruptures: the answer is protected early motion under a hand therapist, which produces gliding, strong repairs. The dorsal blocking splint's angles and the protocol's name belong in the operation note, since the therapist executes half the procedure.

Decision points

  • Both FDS and FDP are divided in zone II. Repair both?

    • Repair both where the tunnel allows

      FDS repair preserves independent PIP flexion and improves FDP glide: the modern default when bulk permits.

    • Repair FDP, sacrifice or partially excise FDS

      In a crowded, damaged tunnel, a gliding single tendon beats two welded ones: a deliberate, documented trade.

    The tunnel's capacity is the constraint: the decision optimises total gliding function, not suture-line count. Either answer is defensible when the reasoning is; neither survives a repair too bulky to move.

  • The referral is five days old and the sheath looks inflamed. Repair tonight?

    • Primary repair within the window

      Clean sharp injuries repair well within days: the window is wider than folklore suggests, and the same operation applies.

    • Washout now, staged reconstruction later

      Established sheath infection (Kanavel's signs) forbids repair into pus: drainage first, and tendon reconstruction another season.

    Time alone rarely closes the primary-repair door; infection slams it: the sheath's state, not the calendar, is the arbiter. Repair into an infected tunnel fails and takes the pulleys with it.

Leaving the OR

The handoff

Procedure
Zone II FDP and FDS repair, ring finger; digital nerve repaired
Repair
Four-strand core with epitendinous suture; full passive glide confirmed on table
Splint
Dorsal blocking splint applied; angles documented
Watch for
Perfusion of the digit, dressing tightness, and the therapy referral actually landing this week

A fictional educational patient, handed over the way real ones are.

The postoperative course

  1. POD 0-5Elevation, splint discipline and the first hand-therapy session: the protocol (early protected motion) starts within days, not weeks.
  2. Weeks 1-6The vulnerable window: the repair is weakest around week one to three, and every session balances glide against rupture. No gripping, no lifting, no exceptions.
  3. Weeks 6-12Graduated strengthening; the splint retires by stages; adhesions that resist therapy declare themselves as fixed flexion or lost glide.
  4. MonthsThe outcome audit is honest: full function, acceptable function, or the tenolysis conversation for repairs that healed strong but stuck. Rupture at any point is an urgent return, not a clinic letter.

Watch it done

Find Flexor tendon repair videos on YouTube

What can go wrong

Surgical-site infection
Live this operation as a case →OR Prep this operationReview the instruments