Flexor Tendon Flashcards
the distal tendon insertions determine the
level offlexion
T
The FDS and FDP tendons within the flexor tendon sheath receive
nutritional supply and eliminate wastes by two ways: vascular perfusion
and synovial diffusion.
well-developed vincular system, which takes off the
common digital arteries and continues to the dorsal aspectofthe tendon
T
The palmar aspect ofthe tendon is relatively avascular,
and the paratenon promotes material exchange by means ofdiffusion
T
The A2 and A4 pulleys originate from the periosteum of the proximal and middle phalanx, respectively. They are the most important pulleys in maintaining grip power and preventing bowstringing of the flexor tendons during active finger flexion.
T
cruciate (Cl-C3) pulleys
They function to accommodate
full flexion and extension of the joints without significant collapse or
expansion ofthe adjacent annular pulleys during finger motion.
Zone I is the area
distal to the insertion of the FDS tendon only involving the FDP
tendon
T
Zone 2 describes the area within the flexor tendon sheath
distal to the Al pulley but proximal to the FDS insertion;
T
Zone 4 tendon injury
is rather uncommon because the overlying trapezium and hamate
prominence shield the tendons in this zone from laceration
T
for smooth gliding and minimize peri tendinous adhesion Sometimes this
requires partial excision of the FDP tendon to decrease the repair
bulk,
F FDS
for smooth gliding and minimize peri tendinous adhesion Sometimes this
requires partial release of the adjacent pulleys
T
In the setting of vascular compromise to the digit we repair the tendons concomitant with vascular injury
T microvascular repair or reconstruction to restore digital perfusion
are indicated, and the lacerated flexor tendons can be repaired at the
same time.
Beyond
6 weeks, the primary repair of flexor tendon is unlikely to succeed why?
because of myostatic contracture of the lacerated tendon and swelling of the tendon ends that do not permit tendons to be retrieved
through the pulleys
later experiments demonstrated the alternative intrinsic
tendon healing without adhesion
T
increasing the suture caliber can increase the tensile strength at
the repair site.20 Similarly, an increased number of core strands also
increases repair strength
T
core strand number is more important than suture caliber in terms
of increasing repair site strength.
T
locking
core suture loops are stronger than grasping loops
T
the location
of the core suture knot, inside or outside of the repair site, has not
been shown to affect the repair site strength
T
Deeply
placed epitendinous sutures provide better repair strength compared to those placed superficially
T
Epitendinous sutures placed
further from the cut edges also improve the tensile strength at the
repair site
T
epitendinous sutures for Zone 2 are recommended in addition to the core sutures
T
Epitendinoud repair placed at 2 mm from the cut edges and
2 mm deep
T
a gap less than 3 mm is the critical gap to facilitate
adequate healing of the tendon and increased repair strength with
time
T
