Foot & Ankle Flashcards
Factors predictive of DM ulcer healing?
- Ankle-brachial index (ABI)
- Greater than 0.5, with normal ranging from 0.9 to 1.3
- Greater than 1.3 indicates inelastic vessels (calcified—
- common in diabetics); not indicative of good flow.n
- Toe pressures
- Greater than 40 mm Hgn
- Transcutaneous oxygen pressures (TcPO2
- Greater than 30 mm Hg
What is the McBride soft tissue release in Hallux valgus? What is the modification in the modified version?
Procedures never appropriate in isolation (high recurrence
rate)
Distal soft tissue release (modified McBride procedure)
Modification—retention of the lateral (fibular)
sesamoid to avoid hallux varus
Medial eminence resection
Medial capsular imbrication
Isolated osteotomy without associated soft tissue
correction
Hallux varus associated with…
Hallux varus—associated with:
Resection of the fibular sesamoid (original McBride
procedure)
Overresection of the medial eminence
Excessive lateral release
Overcorrection of IMA (less 0)
Lesser to deformity? What population?
Lesser-toe deformities occur much more commonly in women
(up to a 5:1 ratio); difference thought to be secondary to high-
fashion shoewear that constricts the forefoot and maintains the
MTP joints in hyperextension.
What happens when you resect both sesamoids in the foot?
Cock-up deformity (or claw toe) will occur if both
sesamoids are excised
Morton Neuroma….where is it most common?
INTERDIGITAL NEURITIS (MORTON NEUROMA)n
Definitionn
Compressive neuropathy of the interdigital nerve, most
commonly in the third web space, followed by the second
web space (Fig. 6.60)
What is the mulder sign?
INTERDIGITAL NEURITIS (MORTON NEUROMA)n
Definitionn
Compressive neuropathy of the interdigital nerve, most
commonly in the third web space, followed by the second
web space (Fig. 6.60) provokes symptoms and occasionally a bursal “click”
with associated pain (Mulder sign).
What is jogger’s foot?
Medial plantar nerve entrapmentn
Nerve provides sensation to the plantar medial aspect of
the foot.n
Entrapment occurs at the knot of Henry (junction of FDL
and FHL tendons).
FDL is plantar to FHL at knot of Henry.
Most common etiology is external compression from
orthotic devices.
Also called jogger’s foot
Conservative treatment is often successful and includes
avoidance of orthotics and of pressure along the plantar
medial hindfoot.
What are the muscle balances in the foot (neuromusc condition)?
The most common deformity of the foot and ankle is
equinovarus.
The equinus component is caused by overactivity of the
gastrocnemius-soleus complex.
The varus is due to relative overactivity of the tibialis
anterior and the tibialis posterior tendons with lesser
contributions from the FHL and FDL.
The posterior tibial tendon is balanced by the
peroneus brevis.
The anterior tibial tendon is balanced by the
peroneus longus.
The anterior tibial tendon is balanced by the Achilles
tendon complex in the sagittal plane.
What is the most common type of CMT?
As a group, the many genetic variants of CMT disease
are referred to as hereditary motor-sensory neuropathies
(HMSNs).
Type I HMSN is the most common presentation of
CMT.
Usually autosomal dominant with a duplication of
chromosome 17
In RA foot, what is the most significant risk factor of developping post op infection?
Vasculitis and soft tissue fragility are common, requiring
diligent care of the soft tissues during nonoperative and
operative management.
Use of immune-mediating pharmacologic therapies in
the perioperative period should be discussed with a
rheumatologist because of possible complications.
Most can be continued (prednisone, methotrexate,
hydroxychloroquine), but the newer biologic agents
(e.g., TNF antagonists) should be discontinued.
Most significant risk factor for development of a
postoperative wound infection: history of previous
wound infection
What is the RA foot reconstruction?
Late (in presence of severe deformity)—“rheumatoid
forefoot reconstruction” (Hoffman procedure) (Fig.
6.76)
First MTP arthrodesis, lesser metatarsal head
resection with pinning of the lesser MTP joints, and
closed osteoclasis of the interphalangeal joints versus
PIP arthroplasty
Silicone arthroplasty not recommended;
complications are cock-up deformity, silicone
synovitis, and osteolysis.
Accomplished through three well-placed
longitudinal dorsal incisions (Fig. 6.77)
Extensor brevis tenotomy and Z-lengthening of the
extensor longus tendons may be necessary.
Most common complication of forefoot
arthroplasty is intractable plantar keratoses.
Single arthrodesis in foot OA/ deformity?
Arthrodesis of single joints leads to significant limitation
in hindfoot inversion/eversion (affects TN > ST > CC).
Isolated TN fusion has a high rate of nonunion, and
given the significant restriction of hindfoot motion
from a TN fusion, an ST fusion is commonly performed
in addition to ensure union without causing any
incremental functional deficit.
Triple arthrodesis is also an appropriate option. If the
CC joint is unaffected, it is more common to not include
the CC joint in the arthrodesis (“medial double”) for a
pes planovalgus deformity.
What is a higher risk for nonunion in ankle fusion? Smoking or prior fusion (rev surgery)?
Increased nonunion rate with history of ankle
arthrodesis or smoking; nonunion rate higher
with prior ankle arthrodesis than with nicotine
use
Etiology of PTTD?
Etiology of PTTD is multifactorial and includes:
Zone of hypovascularity 2–6 cm proximal to the PTT
insertion on the navicular
Overload of the arch due to activity or obesity
Inflammatory disorders such as RA
