ABFAS Comprehensive Questions
(Frequently Tested) with Verified
Answers Graded A+
Diastasis for Lisfranc = a fracture is present - Answer: 2-5 mm of diastis betwen 1st and second
mt base
Chronic lisfrancs--->ct=1 mm diastasis betwen 1st and 2nd mt or an increase of more than 15
degrees in the tarso-metatarsal joint
signs of lisfranc on xray - Answer: fleck sign (1 and 2 met bases)
first ray elevated
arch flattens
MCC direction lisfranc displaces - Answer: Dorsal and Lateral
When to sx correct lisfranc - Answer: >2mm displaced
wait 14 days if too much edema
Approach to ORIF lisfranc fx - Answer: middle cunii start proximal superior medical >to the base
of the 2nd mt possibly, 3rd mt.
the first lag screw=KEY to REDUCTION. T
if needed do a few more lag screws from the the bases metatarsals >cuni.
,If cuni instability **screw across the cunis.communition=plates.
Rules for bunions in the Juvenile pt - Answer: 14-16 yrs. Ideal time frame to do sx for them is
near skel. Maturity 11-15 yoa.
Don't do anything joint destructive /don't remove the fib sesamoid.
take mt adductus into consideration in a peds patient.
Transpositional osteotomies ideal e.g. austin, kalish, offset V for rectus foottype and mod. IMA.
But if they have Mt Adductus, really high IM or really high PASA
Distal metaphyseal peds osteotomies - Answer: Austin, offset v, reverdin, mitchell, wilson and
peabody. Mitchell and wilson SE including shortening, transfer lesions, elevatus, metatarsalgia
How to fix bunion in a peds pt with IM >15 - Answer: Base procedure aka proximal metaphyseal
osteotomy.
-closed or open base wedge, cresentic procedure, lapidus =goal to make first and 2nd mt
parallel without damaging the open physeal plate.
base of proximal phalanx (aka proximal akin) of hallux what does it correct - Answer: Distal
Angle DASA
Fix pasa with mt head osteotomy like REVERDIN=lat cortex intact proximal cut parallel to 1st mt
and distal cut parallel to articular surface
Fix DASA W/ proximal akin
,disadvantage of the fusion vs plasty is the - Answer: fusion has less hallux propulsion and it can
shorten which can then lead to contracture of the ehl or fhl
You can walk it immediately vs plasty you cant
cancellous vs cortical screws - Answer: Cannulated cancellous screws are used for metaphyseal
fractures while cannulated and noncannulated cortical screws are used as lag screws for fixation
of diaphyseal fractures.
The main advantage of cannulated screws is that they can be inserted over a guide wire or
guide pin. The diameter of the guide pin is much smaller than the cannulated screw
Cannulated screws have a hollow central shaft. Both cortical and cancellous screws can be
cannulated.
1st MPJ arthrodesis position - Answer: neutral rotation of the hallux,
10-15 degrees of valgus
20-30 degrees of dorsiflexion in reference to the axis of the first metatarsal
Which does not affect bone healing:
1. Nutritional status, Rheumatoid or methotrexate patient, DM, tobacco hx, extent of initial
injury, osteoporosis, other metabolic diseases, neuropathy - Answer: all do
mcc for ex fix - Answer: 1. m/c complications involve bone healing and not infection
others: 1. delayed, nonunion, implant loosening, fracture, chronic pain, soft tissue
inflammation, ulceration, or gross infection including osteomyelitis
, blood supply to talus - Answer: i.posterior tibial artery, artery of the tarsal canal
dorsalis pedis artery,
perforating peroneal artery.
MCC of talar AVN - Answer: post-traumatic talar fracture
Pain, swelling, with a history of previous injury or trauma. May have mechanical symptoms such
as clicking, locking, or grinding. - Answer: AVN
diagnose by a. Plain XR and MRI remain the most used and beneficial modalities.
Classification of AVN - Answer: i. Hawkins type I fractures are non displaced vertical neck
fractures.
AVN is 10%.
ii. Hawkins type II fractures consist of a vertical talar neck fracture with either subluxation or
displacement of the STJ.
AVN is 42%.
iii. Hawkins type 3 fractures are characterized by a vertical talar neck fracture with subluxation
or dislocation of both the ankle and STJs.
AVN 91%.
iv. Hawkins type IV fractures vertical talar neck fracture with subluxation or dislocation of the
ankle, STJ, and the TNJ.
AVN of 100%.
what is Hawkins sign - Answer: AVN=Hawkins sign: subchondral radiolucent line along the
superior aspect of the talar dome, which classically begins on the medial side of the talar dome,
and appears 6-8 weeks after injury.
(Frequently Tested) with Verified
Answers Graded A+
Diastasis for Lisfranc = a fracture is present - Answer: 2-5 mm of diastis betwen 1st and second
mt base
Chronic lisfrancs--->ct=1 mm diastasis betwen 1st and 2nd mt or an increase of more than 15
degrees in the tarso-metatarsal joint
signs of lisfranc on xray - Answer: fleck sign (1 and 2 met bases)
first ray elevated
arch flattens
MCC direction lisfranc displaces - Answer: Dorsal and Lateral
When to sx correct lisfranc - Answer: >2mm displaced
wait 14 days if too much edema
Approach to ORIF lisfranc fx - Answer: middle cunii start proximal superior medical >to the base
of the 2nd mt possibly, 3rd mt.
the first lag screw=KEY to REDUCTION. T
if needed do a few more lag screws from the the bases metatarsals >cuni.
,If cuni instability **screw across the cunis.communition=plates.
Rules for bunions in the Juvenile pt - Answer: 14-16 yrs. Ideal time frame to do sx for them is
near skel. Maturity 11-15 yoa.
Don't do anything joint destructive /don't remove the fib sesamoid.
take mt adductus into consideration in a peds patient.
Transpositional osteotomies ideal e.g. austin, kalish, offset V for rectus foottype and mod. IMA.
But if they have Mt Adductus, really high IM or really high PASA
Distal metaphyseal peds osteotomies - Answer: Austin, offset v, reverdin, mitchell, wilson and
peabody. Mitchell and wilson SE including shortening, transfer lesions, elevatus, metatarsalgia
How to fix bunion in a peds pt with IM >15 - Answer: Base procedure aka proximal metaphyseal
osteotomy.
-closed or open base wedge, cresentic procedure, lapidus =goal to make first and 2nd mt
parallel without damaging the open physeal plate.
base of proximal phalanx (aka proximal akin) of hallux what does it correct - Answer: Distal
Angle DASA
Fix pasa with mt head osteotomy like REVERDIN=lat cortex intact proximal cut parallel to 1st mt
and distal cut parallel to articular surface
Fix DASA W/ proximal akin
,disadvantage of the fusion vs plasty is the - Answer: fusion has less hallux propulsion and it can
shorten which can then lead to contracture of the ehl or fhl
You can walk it immediately vs plasty you cant
cancellous vs cortical screws - Answer: Cannulated cancellous screws are used for metaphyseal
fractures while cannulated and noncannulated cortical screws are used as lag screws for fixation
of diaphyseal fractures.
The main advantage of cannulated screws is that they can be inserted over a guide wire or
guide pin. The diameter of the guide pin is much smaller than the cannulated screw
Cannulated screws have a hollow central shaft. Both cortical and cancellous screws can be
cannulated.
1st MPJ arthrodesis position - Answer: neutral rotation of the hallux,
10-15 degrees of valgus
20-30 degrees of dorsiflexion in reference to the axis of the first metatarsal
Which does not affect bone healing:
1. Nutritional status, Rheumatoid or methotrexate patient, DM, tobacco hx, extent of initial
injury, osteoporosis, other metabolic diseases, neuropathy - Answer: all do
mcc for ex fix - Answer: 1. m/c complications involve bone healing and not infection
others: 1. delayed, nonunion, implant loosening, fracture, chronic pain, soft tissue
inflammation, ulceration, or gross infection including osteomyelitis
, blood supply to talus - Answer: i.posterior tibial artery, artery of the tarsal canal
dorsalis pedis artery,
perforating peroneal artery.
MCC of talar AVN - Answer: post-traumatic talar fracture
Pain, swelling, with a history of previous injury or trauma. May have mechanical symptoms such
as clicking, locking, or grinding. - Answer: AVN
diagnose by a. Plain XR and MRI remain the most used and beneficial modalities.
Classification of AVN - Answer: i. Hawkins type I fractures are non displaced vertical neck
fractures.
AVN is 10%.
ii. Hawkins type II fractures consist of a vertical talar neck fracture with either subluxation or
displacement of the STJ.
AVN is 42%.
iii. Hawkins type 3 fractures are characterized by a vertical talar neck fracture with subluxation
or dislocation of both the ankle and STJs.
AVN 91%.
iv. Hawkins type IV fractures vertical talar neck fracture with subluxation or dislocation of the
ankle, STJ, and the TNJ.
AVN of 100%.
what is Hawkins sign - Answer: AVN=Hawkins sign: subchondral radiolucent line along the
superior aspect of the talar dome, which classically begins on the medial side of the talar dome,
and appears 6-8 weeks after injury.
