Background: Therapy employing passive finger
flexion and active finger extension with the wrist fixed in flexion
is commonly used after flexor tendon repair. However, this method
of rehabilitation may not produce full tendon excursion because
of buckling of the tendon within its sheath with passive flexion. Studies
of cadavera suggest that the use of synergistic wrist and finger
motion may improve tendon gliding. The purpose of this study was
to assess the effects of passive digital motion, performed with
either wrist fixation or synergistic wrist motion, on adhesion and
gap formation after flexor tendon repair.
Methods: Sixty-six dogs were randomly allocated
to two groups. In each group, two flexor digitorum profundus tendons
of one forepaw were partially (80%) lacerated and then
repaired with a modified Kessler suture. In each group, a different
postoperative therapy (wrist fixation or synergistic motion) was
performed twice daily. The dogs were killed at one week, three weeks,
or six weeks after surgery, and the repaired tendons were evaluated
to determine the adhesion grade and adhesion breaking strength.
Results: The synergistic motion group had a significantly
lower adhesion grade and significantly less adhesion breaking strength than
the wrist fixation group at three and six weeks (p < 0.05). At
one week, there was no significant difference between the two therapy
groups (p > 0.05).
Conclusions: Passive digital flexion and extension
with synergistic wrist motion was an effective therapy after repair
of partial zone-2 lacerations in a canine model.