Concepts
1. Core suture
Strength of repair proportional to
A. Number of strands crossing the gap (not suture type)
B. Suture size (usually non absorbable braided suture 3/0 or 4/0)
2. Repair strength increases more rapidly with early motion stress
3. Dorsal sutures are stronger but may interfere with blood supply
4. Repairs usually rupture at knots
5. Locking loops decrease pull out and increase strength
7. Peripheral Circumferential Suture
- increases repair strength by 10-50%
- reduces gapping and bulk of repair significantly
- closure of epitenon with 6/0 suture
Partial Tendon Lacerations
< 25%
- debride
25 - 25%
- epitenon repair
> 50%
- core and epitenon repair
Early ROM Rehabilitation
1. Load at failure at 3 weeks
- immediately mobilised tendons 3 x > immobilised tendons
- more rapid collagen realignment
- histological exam increased healing response with decreased scar response
2. Early mobilization decreases adhesions
Early Active ROM Protocol
Position in extension blocking splint
- wrist and MCPJ flexed
- DIPJ and PIPJ in extension
Stage 1
- passive flexion using the other hand (5 times per hour)
- active extension of finger in splint
- splint never removed
Stage 2
- once full passive motion gained (each hour)
- 5 x passive finger flexion & active extension
- 5 x active finger flexion & 5 active finger extension
- splint never removed
6 Weeks
- splint removed & active wrist movement
- no resistance
8 weeks
- resistive work (sponge squeezing)
12 Weeks
- normal activity
Incisions
Brunner incisions
- incorporate laceration
- avoid sharp angles <60o
- longitudinal incisions over flexor creases avoided
Identify and protect NV bundles
Expose synovial sheath
- preserve A2 and A4
- can remove other pulleys
Zones of Injury
Zone 1
- distal to FDS (FDP only)
Zone 2
- between A1 pulley and FDS insertion (2 tendons in sheath)
Zone 3
- in palm, lumbrical origin
Zone 4
- in carpal tunnel
Zone 5
- proximal to carpal tunnel
Management
Zone 1
Causes
1. Open / laceration
2. Rugger jersey finger
- most common RF
- caught in jersey whilst grasping
- RF forcibly extended at DIPJ while FDP is contracting maximally
- due to common muscle belly for FDP to LF, RF, MF
Types
Avulsion FDP Type 1
- FDP retracts into palm
- vinculum ruptured
- tender swelling in palm
- may need separate palmar incision
- need to pass under A2 and A4 pulley
- suture tendon to paediatric feeding catheter
- must be repaired in 7-10 days
Avulsion FDP Type 2
- most common type
- retracts to PIPJ level
- vinculum intact
- swelling at PIPJ level
- early reinsertion best
- can be repaired up to 3 months after injury
- may progress to type 1 injury if vinculae give way
Avulsion FDP Type 3
- large bony fragment
- A4 pulley catches fragment & prevents retraction
- early reattachment
Repair
1. Tendon to tendon repair
- if possible
2. Insufficient distal tendon
- prepare bony insertion
- modified Kessler into tendon
- pass suture ends through distal phalanx and nail plate
- tie over button
- use 4.0 monofilament i.e. prolene
- need to remove button and sutures at 8/52
3. Bony avulsion
- ORIF / button repair
Zone 2 / Bunnell No Man's Land
Problem
- both tendons injured
- high risk of bulky repairs / adhesions / poor function
Technique
Tendon laceration
- usually distal to skin cut
- need to retrieve tendons from palm
- A2 & A4 pulleys need preservation
- FDS & FDP both repaired if possible
- may only need one limb of FDS
Core Suture
- 2 x modified Kessler
- can use 2 x loop sutures to create 4 strand modified Kessler
- best to use prolene as will run easier than polyfilament suture
Peripheral suture
- 6.0 prolene running suture
- do dorsal aspect of tendon first, then core, then complete volar aspect
- very important for strength and allowing smooth glide
Zone 3
Delayed repair up to 3 weeks possible
- lumbrical holds tendon
- relatively good prognosis
Zone 4
Rigid compartment
- good result more difficult to achieve
- often complicated by median nerve injury
- should repair within 3 weeks to avoid myostatic muscle contraction
Zone 5
Loose compartment
- good prognosis but associated nerve injuries important prognostically
- quality of repair not so important
- should repair within 3 weeks otherwise muscle contraction occurs