- See:
- Intrinsic Muscles of the Hand:
- Intrinsic Muscles Deficit
- Discussion:
- involves motor transfer to the radial side of the mid proximal phalanx, just distal to the attachment site of the lumbrical (as opposed
to insertion on lateral band);
- this approach emphasizes the primary need to restore MPJ flexion;
- as the fingers flex, MP joint flexion occurs simultaneously;
- graft tension:
- graft is placed under slightly more tension than normal, inorder to create a mild flexion contracture of the MP joiont;
- FDS Transfer Technique:
- indicated for low ulnar nerve palsy;
- contra-indicated w/ combined median and ulnar nerve injuries (4 tailed superficialis transfer would be too weak) or with concomitant flexor
tendon injury or scarring;
- this procedure is also contra-indicated if the goal of surgery is increase in power grip strength;
- FDS harvest from the ring finger should be avoid in high ulnar nerve palsy, (w/ the goal of restoring adductor pollicis function), since
this may significantly decrease power grip;
- procedure involves harvesting ring superficialis, delivering it into the palm, and spliting down its raphe;
- tendon slips are passed thru the lumbrical canal to the radial sides of the ring and long fingers;
- tendon is then anchored to a point just distal to the lumbrical insertion;
- small transverse hole is made in phalanx, and tendon is inserted using a pull out wire;
- the transferred tendon lies volar to the axis of flexion of the CMC and MP joints;
- this varient is technically less demanding that the "dorsal transfer method," but there usually are not dramatic gains in grip strength;
- post op:
- wrist and MP joints are maintained in flexion;
- because the PIP joint has not been included in the transfer, immediate PIP motion may be started immediately;
- PIP stiffness is not a problem;
- no retraining of the superficialis muscle is needed;
- Dorsal Transfer Technique:
- indicated for high ulnar nerve palsy or combined median and ulnar palsy;
- this technique is more technically demanding than the FDS transfer, but has the advantage of providing the patient w/ better grip strength;
- motors include: ECRL or the Brachioradialis;
- a free tendon transfer is required to augment length of the motor;
- grafts enter the palm thru the intermetacarpal space, pass volar to the deep volar metacarpal ligament, thru the lumbrical canal, and are
then attached to the radial side of the proximal phalanx;
- post op:
- wrist is maintained in dorsiflexion and MP joints are maintained in flexion;
- because the PIP joint has not been included in the transfer, immediate PIP motion may be started immediately;
- PIP stiffness is not a problem