- See:
- Primary Flexor Tendon Grafting
- Pulley Reconstruction
- Prosthetic Grafts
- Discussion:
- indicated for delayed or neglected flexor tendon injuries, tendon rupture following previous attempted repair, and in some cases is indicated for zone II tendon injuries;
- probably in most cases, free tendon grafting is indicated for flexor tendon injuries which are dirty or contaminated at the time of injury;
- palmaris longus or plantaris are satisfactory graft choices;
- contra-indications:
- loss of full passive digit ROM;
- w/ isolated FDP loss but good retention of FDS function, tendon reconstruction risks worsening finger function;
- in this case, consider FDP tenodesis or DIP joint fusion;
- Exam:
- pt must have full passive ROM of digits before free tendon grafting can be performed;
- in cases of isolated FDP loss, carefully assess function of the FDS tendon (if this is functioning then consider FDP tenodesis);
- Technique: Stage I (debridment / prosthetic graft insertion):
- exposure:
- phalangeal incisions: midlateral or Bruner skin incision is made to expose involved tendon;
- for index finger, proximal incision extends from radial aspect of proximal finger crease to ulnar aspect of middle crease & radial aspect of the distal crease and then to ulnar aspect of finger pad;
- extension into the palm then follows the palmar creases;
- neurovascular structures are identified;
- annular ligaments are identified;
- save as much as the tendon sheath as possible;
- while protecting annular ligaments, cruciate ligaments are opened to allow access to tendons;
- tendon debridement:
- if the FDP is the damaged tendon, excise the FDP tendon from the palm (at the level of the lumbricals) upto the level of the DIP joint;
- preserve the distal 1 cm of the FDP which will be used to help anchor the free tendon graft;
- avoid injury to profundus stump insertion, since this protects the volar plate and helps maintain a smooth gliding surface;
- assess FDS tendon insertion:
- if the FDS is damaged, then excise the distal 1-2 cm of its insertion;
- if the staged flexor tendon reconstruction of Naam (1997) is to be used, then the proximal stumps of the FDS and FDP are sutured together, for later identification;
- Staged flexor tendon reconstruction using pedicled tendon graft from the flexor digitorum superficialis.
- assessement of tendon sheath environment:
- scaring within flexor sheath, excessive pulley system damage, joint contractures, and/or nerve injury mandate two-stage tendon grafting;
- pulley reconstruction, joint release, or nerve repair should be performed at this point in the case;
- ref: Flexor sheath dilatation with a Fogarty catheter.
- prosthetic grafts are inserted at this point;
- use the largest prosthetic graft that is possible;
- some use a twisted wire, to help pass the graft thru the sheath;
- graft is anchored proximally but left free distally;
- Stage II Reconstruction: (flexor tendon grafting)
- the second stage of free tendon grafting is completed when all signs of infection and significant scarring are absent;
- donor graft:
- palmaris longus;
- plantaris;
- Leversedge, et al (2000): results with using intrasynovial donor tendons for flexor tendon reconstruction in 8 patients (10 digits) at a mean 3.8 years
for neglected or failed primary repair of zone 2 lacerations and for neglected flexor digitorum profundus avulsions;
- flexor digitorum longus to the second toe was used as the donor tendon graft.
- average active motion recovery was 64% and 56% for single-stage and multistage reconstructions, respectively, and was 73% overall for single digit reconstructions;
- ref: Flexor tendon grafting to the hand: An assessment of the intrasynovial donor tendon—A preliminary single-cohort study.
- distal incision is made over previous incision stopping at mid phalanx;
- make a small longitudinal incision in the distal sheath, w/ care not to injure the A4 pulley;
- locate the Hunter rod at the distal FDP stump;
- the rod is left anchored in place until, tendon graft has been harvested;
- proximal incision:
- proximal incision is reopened and the proximal aspect of the sheath is identified;
- distal end of prosthetic graft is cut, and prosthetic graft is pulled distally, pulling the tendon graft thru the sheath;
- anchor the distal end of the tendon graft;
- the distal end is anchored first so that the proximal anastomosis can be used to judge appropriate tendon tension;
- the remaining FDP stump is split and sutured to both sides of the graft;
- use pull through technique to augment the repair;
- distally graft is held in place with a 3-0 Prolene pull out suture tied over a button placed on the finger nail as in Zone I flexor tendon repairs;
- remaining stump of FDP is sutured to tendon graft w/ 4-0 non-absorbable sutures;
- distal incision is closed down to the base of the digit;
- reconstruction with disrupted FDS tendon
- if the staged flexor tendon reconstruction of Naam (1997) is used, then the site of proximal FDS / FDP juncture is located (which
had been sutured together previously);
- FDS of the involved finger is exposed and is divided proximally, hence it is a free tendon graft;
- the free (proximal) end of the FDS tendon graft is sutured to the prosthetic graft;
- free FDS graft is sutured to the remant FDP stump;
- since the proximal portion of the graft has already been sutured together, proper tension needs to be established at this point in the case
- ref: Staged Flexor Tendon Reconstruction Using Pedicled Tendon Graft From the Flexor Digitorum Superficialis.
- reconstruction with intact FDS tendon insertion:
- flexor tendon grafting through the intact sublimis tendons may cause impingement, hence may consider release of one limb of FDS insertion;
- ref: Resection of the flexor digitorum superficialis reduces gliding resistance after zone II flexor digitorum profundus repair in vitro.
- anchoring the proximal tendon end:
- the proximal end is anchored after the distal end, so that tensioning the graft is easier;
- misc:
- a common complication postoperatively is hyperflexion of the DIP joint;
- to avoid this complication, consider inserting a pin across the extended DIP joint for a period of 10-14 days, and in the mean time, have the patient concentrate on PIP motion;
- Post Op Care:
- dorsal split is applied w/ wrist in 40 deg of flexion and MP flexed to 90 deg, until patient is ready to begin passive ROM
Autogenous flexor-tendon grafts. A biomechanical and morphological study in dogs.
Two-stage flexor-tendon reconstruction. Ten-year experience.
Primary Flexor Tendon Repair Followed by Immediate Controlled Mobilization.
Staged flexor tendon reconstruction fingertip to palm.
Staged flexor tendon reconstruction fingertip to palm.
Two-stage Flexor Tendon Reconstruction in Zone II Using Hunter's Technique