Ankle

Question 1

The superficial deltoid ligament and deep deltoid ligaments role

Answer 1

superficial resists hindfoot eversion

Deep: medial stabilizer of ankle; restraint to external rotation fo the talus

Question 2

how does the talus shape affect the ankle motion

Answer 2

Talus is wider anteriorly and narrower posteriorly, ankle rotates into more plantarflexion, thus the talus translate slightly anterior, unlocking itself from the omrtise.

with progressive plantarflexion or extreme dorsiflexion, dislocoation can occur

Question 3

fixed bearing vs mobile bearing implants

Answer 3

fixed bearing, the polyethylene spacer is fixed to either the tibial or talar implant component

mobile bearing: have polyethylene spacer that is NOT attached to either the talar or tibial component and floats between the two . allows for some varus/valgus tilt and axial rotation

Question 4

what does the agility device require for their TAR

Answer 4

arthrodesis of the distal tibiofibular syndesmosis

Question 5

advantage for Hintegra

Answer 5

relies on minimal bone resection for placement in cancellous subchondral bone

Question 6

Ankle/foot positioning for STJ arthrodesis

Answer 6

0-5 deg valgus, 10-15 deg external rotation of foot so 2nd ray aligns with tibial crest

Question 7

pantalar position for fusion

Answer 7

The ideal position for a tibiocalcaneal or pantalararthrodesis fusion is 90 degrees of the foot relative to the leg, with slight ankle and/or hindfoot valgus, and approximately 10-12 degrees of pes abductus.

Question 8

Indication when considering total ankle arthroplasty with ankle valgus as a result of malleolar malunion

Answer 8

fibular lengthening osteotomy

Question 9

Indication when considering total ankle arthroplasty for ankle varus , as a result of chronic ankle instability

Answer 9

a medial malleolus lengthening osteotomy would be indicated

Question 10

contraindications for TAR

Answer 10

• severe osteoporosis
• history of osteomyelitis
• diffuse osteonecrosis
• significant bone defect on the tibial and/or talar site.
• Charcot
• Non-manageable hindfoot malalignment Massive joint laxity (eg, patients with Marfan disease) Highly compromised periarticular soft tissues (eg, in patients with posttraumatic OA who underwent several previous surgeries) Severe sensomotoric dysfunction of foot/ankle Active soft-tissue or bony infection Additionally, TAR should not be considered as the first-choice therapy in patients with a high level of functional demand (eg, contact sports).

relative contraindications for TAR:
-heavy physical work, medium level of sports activities (eg, tennis, jogging, and downhill ski), high body mass index, diabetes, and smoking

-Significant preoperative varus or valgus deformity (>10°)

Question 11

which TAR implant goes from a medial or lateral approach via a malleolar osteotomy

Answer 11

Eclipse Total ankle

Question 12

which TAR implant goes from lateral malleolar osteotomy

Answer 12

Trabecular metal total ankle (zimmer/biomet)

Question 13

which TAR has tibial surface covered with polyethylene flat that fits congruent surface of talar component with a sulcus that allows varus and valgus motion

Answer 13

salto talaris

Question 14

for CBPS, what are the OCD tx

Answer 14

cast immobilization
OATs
 subchondroplasty 
subchondral drilling 
debridement of ostechondral defect

Question 15

CBPS: OCD dx

Answer 15

OCD; osteochondritis disseca

talar dome lesions

Question 16

FDA approved TARs

Answer 16

Agility 
Salto Tolaris 
Eclipse 
Star 
Infinity
Inbone 
Trabecular Metal total ankle

Question 17

which TAR is approved without using cement

Answer 17

STAR

Question 18

which two TARs uses the fibular osteotomy apporach

Answer 18

Eclipse and Trabecular Metal

Question 19

post op protocol for TAR

Answer 19

immobilize for 6 weeks, and then protective weight bearing–> physical therapy

Question 20

What’s a reason to keep the fibula during ankle fusion?

Answer 20

Fibula is required if you want to change ankle arthrodesis to TAR

Question 21

Coronal deformity of __________ would be contraindicated for TAR

Answer 21

> 20 deg

Question 22

What is the most appropriate shoe modification for a patient who has undergone a well-aligned ankle arthrodesis?

Answer 22

rocker sole shoes

Question 23

common complications of TAR

Answer 23

Delayed wound healing (most common), subsidence ( gradual caving in or sinking of implant into bone), loosening, and malleolar fx

Question 24

indications for supramalleolar osteotomies

Answer 24

distal tibial malalignment
Physeal disturbances
Degeneratie arthritis
malpositioned ankle arthritis

does not correct hindfoot deformities

Question 25

what can increase risk for tibial component loosening on a TAR esp for Agility

Answer 25

syndesmotic nonunion

Question 26

What is the most appropriate shoe modification for a patient who has undergone a well-aligned ankle arthrodesis?

Answer 26

rocker sole shoe

Question 27

For any fibular osteotomy, where is the osteotomy typically performed? and what type of osteotomy?

Answer 27

3-5 cm above ankle joint: this area has somewhat meaphyseal and better healing potential

transverse osteotomy ideal

Question 28

what is the most important part of the surgical technique for fibular lengthening

Answer 28

establishing good mobilization of syndesmosis to successfully lengthen and have fibula rotated into proper position

Question 29

Tx for Berndt and Harty I-IV

Answer 29

Stage I and II, III medial lesions- conservative treatement: I: reduced activity, limited ankle motion

II/III:casting, patellar brace, ankle corsets, arch supports

III lateral/chronic ocd/stage IV:
removal of loose bodies and chronic lesions, drilling and curettage of defect, reductions with fixation of large fragments in acute injuries
-two K wires
- (absorbable) polyglycolic acid rod
-screws (1.5 or 2.0)
-Fibrin sealant (physiologic glue containing freeze dried human fibrinogen, bovine aprotinin, calcium chloride, and bovine thrombine)–granulation tissue replace this overtime; fibrin adhesive lasts only for 1 week

-mosaicplasty
ORIF-for displaced fragment; usually early injury of stage IV. chronic lesions more difficult for chronic lesion because of fibrous tissue that forms on cancellous bone

Question 30

When are the collateral ligaments typically ruptured to some degree for OCD lesions

Answer 30

Grade II-Stage IV

Question 31

Superficial peroneal nerve emerges from the crural fascia approximately

Answer 31

The superficial peroneal nerve is often encountered and emerges from the crural fascia 10-12 cm from the distal tip of the fibula.

Question 32

What is the bosworth dislocation and what prevents it from being able to reduce?

Answer 32

rare fracture-dislocation of the ankle where the fibula becomes entrapped behind the tibia and becomes irreducible
posterolateral ridge of the distal tibia hinders reduction of the fibula

Question 33

What is the ankle fusion technique that is indicated in a child to preserve the potential for growth of the distal tibial and fibular physis?

Answer 33

distraction-compression fusion

Question 34

increased medial clear space in ankle indicates what stability

Answer 34

syndesmotic instability