Chpt 59: STJ arthrodesis

Question 1

what causes increase in flexibility of midtarsal joints

Answer 1

CC and TN joints become parallel

Question 2

TN arthrodesis decrease the amt of motion of STJ

Answer 2

only 8-9% STJ motion

Question 3

STJ arthodesis limits how much of the TN and CCJ

Answer 3

25% of TNJ motion remains, 55% of CCJ

Question 4

L shaped incision placement for STJ

Answer 4

horizonal leg of L should be superior to peronal tendons and sural N

Vertical arm of L made proximal to extensor digitorum belly then reflects EDB distal to level of CC

Question 5

Relation of long axis bissection of tibia and calcaneus

Answer 5

should be parallel

Question 6

placement of screws for STJ fusion and purpose of screw

Answer 6

1st screw: perpendicular to posterior facet for compression

2nd screw: eliminate rotational force

Question 7

post op protocol for STJ fusion

Answer 7

NWB for 8 weeks ; PWB 4 weeks- crutches/walker–>orthotics/PT

Question 8

What is valgus/varus defomity that becomes a contraindication for arthroscopic STJ arthrodesis

Answer 8

Greater than 15 degrees of valgus or more than 5 degrees of varus malalignment is a contraindication to arthroscopic subtalar joint fusion.