Page 21 - 2021 Winter CMTA Report

to weaken, the toe extensor joints in the small toes and two muscles flex the toes down in a
muscles have to work harder in the big toe, and they com- non-CMT patient, which means
and harder to help lift the ankle. monly all deform in different that division of the FDL will go
And with the toe extensors directions. That multiplane largely unnoticed.
working harder than normal, the deformity is what makes toe In CMT patients, however,
toes begin to deform into a surgery tricky. The loss of intrin- these other muscles are often
clawed position. It happens so sic muscle function causes the very weak or completely para-
slowly that few patients realize joint at the base of the toe, the lyzed. Preservation of the FDL is
what is going on. Every day in metatarsal-phalangeal (MTP) therefore important, as it is the
the office I see a CMT patient joint, to extend upward. The only working muscle that pro-
who can move their ankle up middle joint of the small toe, the vides flexion power to the toes.
but only because of the strong proximal interphalangeal (PIP) An even more important rea-
toe extensors. Good for the joint, flexes downward and the son not to divide a strong FDL is
ankle, but ultimately very bad joint closest to the nail in the that it can be used to reconstruct
for the toes, which get deformed distal interphalangeal (DIP) ankle motion in the future if the
by the tendon over-pulling with joint can go in either direction. CMT disease progresses. Please
each step. The goal of surgery is to look at my Instagram (@Charcot-
As the toes deform into a straighten all the joints and end marietoothsurgery), and you will
clawed position a lot of bad up with toes that fit comfortably see many videos of patients who
things can happen to the foot. into normal shoes. have avoided braces by transfer of
The cushioning fat pad under- There is no consensus on the the FDL to restore ankle motion.
neath the toes starts to be pulled best approach to toe surgery. A surgical fusion of the PIP joint
out of position. The bones While all surgeons agree that the is often performed when the FDL
(metatarsal heads) become more release of soft tissue contrac- is preserved to prevent a recur-
prominent on the bottom of the tures is essential, they disagree rence of the deformity. Fusions of
foot, with nothing but skin on the role of PIP fusion, tendon the PIP joints have little impact
between them and the floor. lengthening and tendon release. on function. The small joint in
Walking barefoot on a hard sur- Over the years, my approach to the big toe, the interphalangeal
face becomes intolerable. CMT toe deformity has changed. joint, is another joint that often
Because the toes are no longer in In non-CMT patients, division of requires fusion during toe
touch with the ground, balance the long flexor tendon (FDL) of surgery, with hardly any compro-
is affected and push-off strength the toe is commonly performed. mise in function. A final key
is diminished, which further The FDL muscle arises in the element of the surgery is to take
compromises gait. Custom cush- leg, extends down to the foot the toe extensors, if they are
ioned shoe inserts (orthotics) where it becomes tendinous and strong, and transfer them to the
can help, along with a shoe that inserts onto the tip of the toe. top of the foot where they will
has a roomy toe-box (extra-depth The FDL tendon/muscle is often help lift the ankle.
shoes). a deforming force, and its divi- Understandably, toe surgery
To understand what has to sion can help correct the toe is usually the last priority for
be corrected with surgery, it’s deformity. The division can be CMT patients. A crooked foot
useful to take a closer look at the done through a tiny incision and loss of ankle function need
toe deformity. There are three underneath the toe. Two other to be corrected first to keep a
person walking and out of a
brace. Sometimes everything can
This is the fourth in Dr. Glenn Pfeffer’s four-part
be reconstructed during the
series on The Surgical Correction of the CMT Foot. same surgery, but not always.
The other three parts are: There is a limit to what the foot
Part 1: IS SURGERY RIGHT FOR YOU, can tolerate during an operation,
Winter 2020 CMTA Report, page 14 and a second surgery for the toes
Part 2: TENDON TRANSFERS, may be needed. It’s a lot to go
Spring 2020 CMTA Report, page 4 through, but absolutely worth it.
Part 3: THE ROLE OF JOINT FUSION, The process is a marathon, not a
Summer 2020 CMTA Report, page 21 sprint, but so gratifying when
you win. k

WINTER 2021 THE CMTA REPORT 21