72: Arthrodesis Procedures - Smith

Question 1

indications for triple arthrodesis

Answer 1

• PAIN, deformitly, instability, progression
• valgus foot deformity
  
  • collapsing pes planovalgus
  • ruptured tibialis post tendon
  • tarsal coalition and arthritic deformities
    
    • congenital, rheumatoid, degenerative, posttraumatic
• varus foot deformity
  
  • cavus
  • cavovarus
  • talipes equinovarus
• miscellaneous
  
  • lateral ankle instability and ankle equinus
  • neuromuscular disease
    
    • hereditary familial sensorimotor neuropathies
    • paralytic deformities
    • charcot jt deformities
    • other dz affecting the spinal cord adn brain

Question 2

what jts are fused in triple arthrodesis?

Answer 2

fusion STJ and CC and TN jt

Question 3

triple arthrodesis procedure names

Answer 3

Ryerson ***

Hoke **

Lambrinudi

Brewster

Dunn

Seiffert or break

Question 4

complicatiosn of triple arthrodesis

Answer 4

• pseudoarthrosis/non-union
  
  • 7-23%
  • usually at talonavicular jt
• develpment of DJD in adjacent jts
• AVN
• ankle instability

Question 5

how is the foot positioned for triple arthrodesis?

Answer 5

• May accommodate deformity in all three body planes by resection of bone at the joints
• Arthrodesis position of rearfoot should be 0 - 5 degrees of valgus (thou shall not varus - fusion position STJ)
• Arthrodesis position of forefoot should be parallel to the ground and perpendicular to the heel ***

Question 6

fixation of triple arthrodesis?

Answer 6

• Three 6.5 mm partially threaded cancellous screws (lag design)
  
  • threads must cross the fusion site
• May use smaller screws or staples across midtarsal joint
• May staple all three arthrodesis sites
• Steinmann pins

Question 7

type of incision to be made for triple arthrodesis

Answer 7

ollier’s incision

• lateral approach from tip of lateral malleolus to the base of the metatarsals

also make a medial incision to access the TN jt better

Question 8

review anatomy near incision

Answer 8

Question 9

order of resection

Answer 9

1st: midtarsal joint (CC, TN)

2nd: STJ

FUSE In the reverse order

temp fixate STJ w/ cannulated guide wire

position the forefoot and temp fixate

then fixate STJ, CC, TN

Question 10

post op care triple arthrodesis

Answer 10

• short leg cast for 12 wks NWB
• partial WB for additional 4 wk

Question 11

indications ankle arthrodesis

Answer 11

• Severe pain and/or deformity
  
  • DJD: S/P ankle fracture
  • RA
  • Talar collapse
  • Infection
  • Drop foot
  • Congenital deformities
  • Ankle implant revision

Question 12

ankle arthrodesis positioning

Answer 12

• right ankle to leg ( 0 degrees dorsiflexion)
• body can tolerate 5 degrees of plantarflexion
• external rotation of 13-15 degrees foot (line up tibial tuberosity with the 2nd toe)

Question 13

pantalar arthrodesis

Answer 13

ankle AND triple arthrodesis