1. Tendon Transfer (Mahan) Flashcards
define:
tendon transfer
the detachment of a tendon of a functioning muscle at its insertion and RELOCATION to a new insertion
define:
tendon transposition
REROUTING of the course of a muscle WITHOUT detachment
to assist other functions
define:
tendon suspension
tendon procedures designed to SUPPORT a structure
e.g. young’s suspension
what provides the majority of tendon circulation?
majority comes from paratenon or mesotenon
along STRAIGHT COURSE, tendon is surrounded by:
paratenon;
e.g. tendo achilles follows a straight course;
paratenon looks like a spider web; when incised, becomes very hypervascular
along ANGLED COURSE, tendon is surrounded by:
surrounded by tendon SHEATH;
e.g. peroneal tendons, TP, FDL, FHL
how is strength affected by muscle transfer?
transferred muscles lose ONE GRADE of strength
when selecting muscle for transfer, what should you consider?
- adequate strength
- functionally similar (same gait phase, or suitable for phase conversion)
- long term function
grading system for MMT:
high level
- 5: normal
- 4: good
- 3: fair
- 2: poor
- 1: trace
- 0: zero
which muscle become weak over time with
Charcot Marie tooth?
- TA/extensors/peroneals become weak over time in CMT –> won’t maintain strength long term
what is a good muscle to transfer for CMT?
**TP is not affected by CMT –> will maintain strength long term, better muscle to transfer
describe surgical technique for tendon transfer
-
transfer in a straight line (will be more effective in pulling),
- longer lever arm increases muscular force,
- must consider effect of muscle on particular axis of motion you are trying to affect
- transfer along an anatomical course,
- preserve gliding function,
- appropriate tension,
- fix tendon insertion to bone
types of fixation in tendon transfer attachments
- Tendon to tendon attachment
- Tendon to periosteum
- Tendon to bone (most effective as an anchoring device)
with tendon to bone-type tendon attachment,
describe possible fixations
- bone anchors
- trephine hole (hole in bone)
- screw and polyacetyl washer
- suture with external button
how to find 3rd cuneiform during surgery
follow 3rd MT backward, take a C-arm picture
how do you recognize extensor substitution hammertoes?
extensor tendons pulling toes up during swing phase
what procedure is jones suspension usually combined with?
Usually combined with hallux IPJ fusion
why attach (EDL) to the 3rd cuneiform in Hibbs suspension?
3rd cuneiform it is the central point of the foot
key difference between jones suspension and hibbs suspension
Jones = EHL transfer
Hibbs = EDL transfer
how often is peroneus tertius muscle present?
90% of the time
in the STATT procedure,
if we have split tendon and attached it half medially/half laterally, what have we accomplished?
more effective in ankle dorsiflexion as it is more perpendicular to ankle joint axis
important considerations with tibialis posterior tendon transfer
- Option – transfer superficially over medial malleolus (easier but not perpendicular to axis of motion so not as mechanically effective)
-
Transfer of TP may require talo-navicular fusion to prevent collapse
- If you have a functioning PB, you will likely get abduction of foot around midtarsal joint and collapse once you transfer TP
- Avoid entrapment of tendon in interosseous membrane by making large incision
post-op management for tendon transfer procedures
- Immobilization at right angle and in neutral position for 4-6 weeks until attachment secure
- Movement – after 3 weeks, motion helps to prevent adhesion
post-op mgmt: FUNCTION
isometric exercises for strength
