Foot - Complications Flashcards
grafts
which grafts contract more?
The thinner the graft is, the more likely it is to contract.
STSG will contract more than FTSG.
most common complication after ORIF of displaced talar neck fx
post-traumatic arthritis
nerve injury
During repair of the peroneal tendon care is taken to avoid damage to the sural nerve. Damage to the sural nerve myelin sheath but an intact endoneurial structure, where Wallerian degeneration does not occur is an example of what?
Neuropraxia. EXPLANATION: Wallerian degeneration occurs when a nerve is crushed or cut and the distal portion of the axon degenerates. “A complete transection or crushing injury of a peripheral nerve (neurotmesis) has no potential for regeneration unless the endoneurium and axons are reapproximated. Lesser injuries with the endoneurial structure intact, with (neuropraxia) or without (axonotomesis) axonal continuity, have a better prognosis for axonal regrowth and recovery of function. “
toxic dose
A 34 year old, 60kg female who recently underwent recent elective foot surgery and is suspected to have lidocaine toxicity. What is the calculated toxic dose of lidoc**aine (without epinephrine) for this patient?
- Toxic dose for Lidocaine plain = 4.5mg/kg,
- Lidocaine with epinephrine = 7mg/kg.
- Toxic dose for Marcaine plain = 3mg/kg.
60kg x 4.5mg = 270mg. 270mg % (10mg/mL) = 27mL
scarf
what causes bone troughing in scarf osteotomy?
Bone troughing is created when the osteotomy is performed mostly in diaphyseal bone allowing the displaced cortices of bone to collapse into the medullary canal causing elevation of the distal fragment.
(so you should make the distal saw cut in metaphyseal bone to prevent troughing)
white toe
Treatments for arterial insufficiency and white toe:
- Place foot in dependent position
- loosen bandage
- twist k-wire
- apply heat to small of back
- PT block
- remove k-wire
- remove dressing, and may consider opening wound.
Considerations may also be made for Nitroglycerine paste/patch proximally on the ankle or vasodilators.
5 W’s
Five W’s: (Wind, Water, Wound, Walking, Wonder drugs).
* WIND: 12-24 hours = pulmonary atelectasis and post-op hyperthermia.
* WATER: 24 hours = UTI, urinary retention.
* WALK: 48 hours = PE, DVT.
* WOUND: 72 hours = surgical site infection.
* WONDER DRUG = Anytime, drug-induced.
for shortening during lapidus, do this:
As a general rule if only the articular cartilage is removed, less than 0.5cm of shortening occurs.
* If between 0.5-1.0 cm of shortening occurs, then the first metatarsal should be fixated in slight plantarflexion. Dorsiflexing the first metatarsal may lead to transfer metatarsalgia.
* For shortening greater than 1.0cm, weil osteotomies are recommended on the 2nd and 3rd metatarsals or a bone graft may be added at the 1st metatarsal cuneiform joint.
common complication of Youngswick procedure
Transfer metatarsalgia is a common complication due to the first metatarsal shortening seen in the Youngswick procedure.
causes of failed tarsal tunnel release
- double crush syndrome
- adhesive neuritis
- intraneural damage
Interossei
Following an overzealous lateral release of the 1st interspace, you notice that the 2nd digit abducts, drifting towards the 3rd digit. Which structure was likely damaged?
1st dorsal interossei. EXPLANATION: There are four dorsal interossei and 3 plantar interossei. The bipennate dorsal interossei abduct the digits away from the 2nd toe and the unipennate plantar interossei adduct the digits towards the 2nd toe. An injury to the 1st dorsal interossei would cause the 2nd digit to abduct and drift towards the 3rd toe.
most common nonunion site during triple arthrodesis
TALONAVICULAR
The most frequent complication after triple arthrodesis is a nonunion. The most frequent site of nonunion is at the talonavicular joint. This is likely due to bone sclerosis and challenging joint exposure. During a nonunion in a triple arthrodesis, if 2 out of 3 of the joints are well fused, the nonunion site may often be asymptomatic.
excessive resection of medial eminence in modified mcbride can cause:
This can lead to loss of the medial bony buttress for the proximal phalanx, allowing for varus rotation of the hallux. Loss of part of the tibial sesamoid groove will destabilize the tibial sesamoid, allowing MEDIAL subluxation and will further contribute to the varus deforming force of the FHB
keloids:
cause and treatment
result from abnormal surgical scar healing. They most often are a result of incisions which experience high tension. The mainstay of treatment - intralesional steriod injections - are usually administered 3 to 4 times. The steroids also improve pain and itching frequently associated with keloids. Other therapies include pressure therapy and radiation therapy. These are generally less successful.
type of HT after excessive achilles lengthening
flexor SUBSTITUTION
52 year old woman who underwent a resection of 3rd interspace neuroma through a dorsal approach presents with new developing hammertoe deformities. This is most likely due to the resection of which structure?
Deep transverse intermetatarsal ligament. EXPLANATION: When the deep transverse intermetatarsal ligament is severed a neurectomy procedure via a dorsal approach, the adjacent toes may begin to contract dorsally. This occurs because of loss of the ligament fulcrum.
peds
Accidental, complete release of the deep deltoid during a soft tissue clubfoot correction would most likely lead too:
Pes planus. EXPLANATION: The deep deltoid should be preserved during a soft-tissue release of a resistant clubfoot, and only the most posterior portion of the deep deltoid may be cut if the talus is still resistant to roll back into the ankle joint. Releasing the tibiotalar/deep deltoid is likely to cause a pes planus deformity.
tarsal tunnel
MC cause of failed tarsal tunnel surgery
Inadequate decompression. EXPLANATION: “Inadequate decompression has been reported as the most common indication for revisional surgery.” “Often, the distal tibial nerve and its branches are not adequately explored and released by the primary surgeon. The superficial and deep fascia of the abductor hallucis may not have been incised to complete the distal release of the MPN, LPN, and FBLPN. The patient usually describes no improvement or partial improvement of symptoms after the release, depending on the extent of the release and what remains compressed. On physical examination, there is usually no significant tenderness proximally over the tibial nerve that was released. There may be an area of point tenderness and a positive percussion paresthesia sign distally over the MPN and LPN in the region of the abductor hallucis muscle.
silver nitrate
how does silver nitrate appear on radiograph?
Cauterisation with silver nitrate is common in podiatry procedures. Silver nitrate has a high density and a mass attenuation coefficient making it highly radiopaque. It is often mistaken radiographically for foreign body, bone growth, or pathologic.
nerve
what nerve gets commonly trapped under medial heel?
The first branch of the lateral plantar nerve. EXPLANATION: The first branch of the lateral plantar nerve, or Baxter’s nerve is an inferior calcaneal nerve that can become entrapped along the medial heel.
