Extensor Tendon Repair Flashcards
The mainstay of rehabilitation at the digital level (zones
1-4) remains static splinting
T
early motion protocols have shown promising results in more proximal injuries (zones 5-8
T
extensors exhibit minimal excursion
T
Due to the superficial position of extensor tendons, they are vulnerable to injury and exposure
T
The
stronger opposing action of the flexor system makes early rehabilitation even more problematic
T
The deffiuclities with extensors tendons
the proximity of the tendons to bone, the high incidence of associated periosteal stripping and capsular injuries, and
the limited excursion of the extensors makes repair prone to adherence. Furthermore, the mechanical strength of the repair and status
of local soft and hard tissues may not allow early mobilization. The
stronger opposing action of the flexor system makes early rehabilitation even more problematic
BR is not a wrist or
digital extensor-it flexes the elbow and it supply by radial nerve
T
BR and ECRL are innervated above the elbow,
whereas ECRB is innervated below the elbow
T
a radial nerve
laceration at or below the elbow is likely to maintain wrist extensor
function
T
the last muscle to receive innervation
from the PIN
the extensor
indicis proprius (EIP)
the last to recover after a nerve injury
the extensor
indicis proprius (EIP)
EIP . EDM they typically lie ulnar to the EDC
at the level of the MP joints
T
The attachments of the extrinsic finger extensors onto the sagittal band make them effective extensors of the MCP
T
EPL forms the dorsal boundary of the anatomic snuffbox
T
the interossei
are the primary flexors of the finger MP joints
T
the interossei course dorsal to
the deep transverse metacarpal ligament
T
here are no juncturae that link to the thumb extensors.
T
The lumbrical muscles lie on the ulnar side of the
respective flexor tendon
T
They course volar to the deep transverse
metacarpal ligament before attaching to the radial lateral band of the
respective finger
T
The intrinsic extensor tendons lie volar to the axis of rotation of
the MP joint and dorsal to the axis of rotation of the IP joints
T
Intrinsic muscle action
is also responsible for volumetric grip that starts with coordinated
MP joint flexion and simultaneous IP joint extension
t
Patients with
combined lower median and ulnar nerve palsy are unable to perform volumetric grip, and instead initiate finger flexion at the IP
T
The intrinsic muscles of the thumb are mainly involved in rotational motion.
T
Why patient still be able to extend the thump in case of EPL in jury ?
the adductor pollicis (ulnar) and the
abductor pollicis brevis (radial) insert onto the EPL tendon at the
MP joint level, which along with the EPB, gives them the ability to
extend the IP joint of the thumb at least to neutral
The lateral slips pass on either side ofthe PIP joint and merge with
the lateral bands forming the conjoined lateral bands
t
The lateral slips pass on either side ofthe PIP joint and merge with
the lateral bands forming the conjoined lateral bands
t
The oblique retinacular ligament (ORL, of
Landsmeer) arises from the lateral aspect of the flexor tendon sheath
at the neck of the proximal phalanx (A2 pulley) and passes volar to
the axis ofrotation ofthe PIP joint, inserting onto the extensor mechanism along the middle phalanx
t
What is the medaiter of MCP extension ?
Historically, it was thought to be mediated by the sagittal bands
recent evidence suggests that the extensor continuation to the extensor hood and middle phalanx is the major mediator
of MP extension
Digital extensor tendon excursion is much wider at the forearm
and wrist level than the digit
T
The excursion of a common extensor
proximal to the wrist is approximately 5 cm
T
Every millimeter of extensor tendon lengthening over the proximal phalanx leads to 12° of extension deficit at the PIP joint.
T
the DIP joint where each millimeter of
relative terminal tendon lengthening results in 25° of extension lag.
T
zone 1 and 2 injuries requires static splinting for
6 weeks followed by night splinting and range of motion exercises
T
Early controlled motion
using dynamic splinting has shown promising results for zone 4 to 7
T
dynamic splinting suited for patients who are compliant
and have associated bony and soft tissue injuries
T
The idea is that
early controlled gliding of the tendon will break up impending adhesions while minimizing risk of rupture.
T
Dynamic splinting protocols
are just as effective as early active motion protocols with less risk of
tendon rupture
T
More proximal injuries in zones 8 and 9 carry the
least risk of adhesions and can be treated with static splinting for 3
to 4 weeks.
T
The EIP is absent in 4% ofindividuals
T
The extensor digitorum brevis manus muscle is an anomalous dorsal
muscle, present in 3% ofhands, which arises distally on the wrist between
the index and middle finger metacarpals
T
The zone one extensors tendons injury is more commonly closed rupture
T
The terminal tendon usually inserts
onto a thin area on the dorsal/proximal aspect of the distal phalanx. This area corresponds lo the dorsal ledge of the epiphysis prior to
skeletal maturity
T