Tendon transfers in the foot and ankle is complicated. The
joints must be flexible and the muscle strength should be Grade IV or more for
a tendon transfer to achieve its effect. Here is the mnemonic to remember the
structures at the medial side of the ankle (Tom, Dick, and Harry): This
mnemonic (Tom, Dick, and Harry) contains the muscles that are the horsepower
for the tendon transfer in the foot and the ankle. The T, D, a, n, and H of Tom, Dick and Harry correspond to Tibialis posterior, flexor Digitorum longus, posterior tibial artery, tibial nerve and flexor Hallucis
longus. These three muscles, the flexor Hallucis longus, the flexor Digitorum
longus, and the tibialis posterior are very important tendons that can be used
for tendon transfers. The flexor halluces longus transfer can be used if there
is a large chronic defect that results from Achilles tendon tear, and if the
gap of the tear is 5 cm or more, then you transfer the flexor halluces longus
tendon. The flexor hallucis longus is next to the Achilles tendon, you can
transfer this tendon. The same concept may be done with the tibialis posterior
tendon tear (stage II), which means that is flexible and it may be treated with
a tendon transfer by the tendon that is next to the tibialis posterior, the flexor
digitorum longus tendon. You must add a bony realignment procedure such as
medial calcaneal displacement osteotomy. Lateral column lengthening is also
done if there is excessive forefoot abduction (too many toes), more than 40%
talonavicular uncoverage. When there is chronic tear of both peroneal tendons,
you will transfer the flexor hallucis longus when both tendons are involved and
this can be treated by tenodesis to the healthy tendon if only on tendon is
involved. You will use the girdle stone procedure, which is flexor to extensor
of the lesser toes for flexible hammer toe and claw toes. In
Charcot-Marie-Tooth disease, the patient will have varus of the hindfoot,
cavus, and plantar flexion of the first metatarsal. When the deformity of the
foot is flexible, you will do a soft tissue procedure. You will transfer the
peroneus longus tendon to the peroneus brevis tendon and this will eliminate
the strong plantar flexion of the first ray and this improves the eversion
power of the peroneus brevis muscle. Transfer of the tibialis posterior to the
dorsum of the foot through the interosseous membrane will decrease the varus
movement and it will assist in ankle dorsiflexion. Equinovaurs foot is the most common deficit
following a stroke or traumatic brain injury, this occurs due to over activity
of the tibialis anterior muscle. This condition can be treated with split
tibialis anterior tendon transfer (SPLATT) combined with Achilles tendon
lengthening or gastrocnemius recession. The deformity has to be flexible. Peroneal nerve palsy or foot drop: posterior
tibial tendon transfer through the interosseous membrane to the dorsum of the
foot. The chopart amputation is a partial foot amputation through the calcaneal
cuboid and talonavicular joints, transferring the tibialis and lengthening of
the Achilles tendon to avoid equinus deformity of the hindfoot. Dynamic
supination deformity in the swing phase can occur following Ponseti casting for
a club foot. This occurs due to the overpull of the tibialis anterior. This is
treated with a tibialis anterior tendon transfer to the lateral cuneiform.
Monday, January 27, 2020
Monday, January 20, 2020
Opioid Epidemic
Monday, January 13, 2020
Stress Fractures of the Metatarsal Bones
Bone is a living tissue, and it responds to stress by making
new bone. When the bone fails to respond adequately to stress, a fatigue
fracture may occur. The stress fracture occurs when the bone fails due to
repetitive small stresses (microtrauma). The fracture can present itself early
on as a minor injury with minor symptoms. If the fracture is not treated
adequately it can become very disabling. A high index of suspicion is necessary
for the diagnosis of stress fractures of the metatarsal bones. In athletes,
there may be localized pain that worsens with progressive activity such as
increased training, increased running mileage, a change in running surface, or
changing shoes. Early on, x-ray may be negative in the majority of patients.
Bone scan or MRI can be used to detect early activity in the bone. Usually the
patient will have vague symptoms. The patient may see different doctors in
order to obtain different opinions. A lot of tests may be done, and a neuroma
or metatarsalgia may be given as a diagnosis. Female athletes who have
decreased bone density and possible eating disorders will have an increased
incidence of stress fracture of the metatarsal bones. Female athletes with
stress fractures should have a complete dietary and menstrual history. There is
a correlation between eating disorders, amenorrhoea, and osteoporosis in female
athletes. This is the common areas for stress fractures of the metatarsal
bones. In runners, the fracture usually occurs in the metatarsal neck. In
dancers, the fracture occurs at the base of the 2nd metatarsal.
Fracture may result in delayed union. Restrict weight bearing for 6 weeks. Look
for anatomic causes of fracture in the 2nd and 3rd
metatarsal neck such as heel cord tenderness, a short 1st
metatarsal, or a long 2nd metatarsal. Check for metabolic bone
disease, osteoporosis, or osteomalacia. Upon physical examination, the patient
will have tenderness, induration, and maybe a mass. They will also have a cavus
foot, and the MRI and bone scan can be helpful. Metatarsal shaft stress
fractures can occur due to the stress of weight bearing or prolonged walking.
The fracture is sometimes called a “march” fracture that occurs in military
recruits and in runners who increase activity levels. It usually occurs in the
2nd metatarsal followed by the 3rd metatarsal in
frequency. The fracture is diaphyseal in location, and there will be localized
tenderness at the fracture site. The 2nd metatarsal is the longest
and most rigid of the metatarsal bones, and it is usually exposed to greater
repetitive stresses. X-rays are usually normal. A bone scan or MRI may be
needed. Fracture of the proximal 5th metatarsal occurs in a
watershed area of the blood supply that is susceptible to stress fracture
nonunion. The blood supply in this area is tenuous. Healing is difficult with a
high incidence of delayed and nonunion. The stress fracture occurs distal to
the 4th and 5th intermetatarsal joint. The Jones fracture is an acute fracture, and
a stress fracture is a chronic condition that will require surgery. There are
three types of fractures at the proximal fifth metatarsal: zone I, zone II, and
zone III. Zone I is a tuberosity avulsion fracture. Zone II is a Jones
fracture. Zone III is a stress fracture. The stress fracture occurs distal to
the ligament that connects the 4th and 5th metatarsal
together. The stress fracture can occur in cavus foot due to increased ground
reaction force over the 5th metatarsal. It will be overloaded on the
lateral border of the foot. There will be dull pain activity related symptoms
before the stress fracture shows up on x-ray. X-rays will show the fracture and
its location. The x-ray will show varying degrees of sclerosis and widening of
the fracture line. Treatment is a lag screw fixation with or without bone
graft.
Monday, January 6, 2020
Intertrochanteric Hip Fractures
Intertrochanteric hip fractures with a regular fracture
pattern can be either stable or unstable. The obliquity of the
intertrochanteric fracture is different than in the reverse oblique fracture
pattern. Stable intertrochanteric fracture is stable and most studies show that
there is equal outcome between the sliding hip screw and the intramedullary
nail for a stable fracture pattern (the sliding hip screw is cheaper). A
construct with two screws is as good as a construct with three of four screws.
A displaced fracture is probably a high energy fracture, but it is not
comminuted. If this fracture does not align with traction on the fracture
table, then you need to do open reduction, and if the fracture appears stable
after open reduction, it is easier when you are there to do compression hip
screw. The best treatment for a reverse oblique fracture is cephalomedullary
nail. A sliding hip screw may fail if used for reverse oblique hip fractures.
Unstable fractures are best treated with a cephalomedullary nail. A fracture of
the hip above a retrograde nail will require reduction and internal fixation
with a compression hip screw. An antegrade nail for this hip fracture will not
work unless you remove the retrograde nail which can be a much bigger operation
than using a compression hip screw. A thin or incompetent lateral wall
increases the chances of intraoperative lateral wall blow out. This
intraoperative complication increases the chances of postoperative failure of
the hardware and the need for reoperation. If the lateral wall thickness is
less than 20 mm, then the hip fracture should not be treated with a compression
hip screw. The integrity of the lateral wall is a predictor for fracture
pattern stability, and it is an x-ray sign that guides the implant choice.
Subscribe to:
Posts (Atom)