Triple Arthodesis



Able to achieve relatively high level of function after STJ fusion

- previously believed that isolated STJ fusion should not be performed

- believed that triple arthrodesis was operation of choice for hindfoot

- STJ fusion has superior result with less stress on AJ


Average loss of DF 30% / PF 10%


Position of hindfoot determines flexibility of transverse tarsal (CCJ & TNJ) joints

- imperative that fusion be positioned in ~ 5o valgus 

- permits TTJ mobility

- if varus TTJ locked & patient tends to walk on lateral aspect of foot 


Indications for STJ arthrodesis


 Subtalar Arthritis


Post traumatic / calcaneal fracture




Primary OA




Talar Coalition CN 1Calcaneonavicular coalition subtalar OA MRI


Tibialis posterior dysfunction


Neuromuscular disorders

- instability

- CMT / polio / nerve injury


Indication for Triple Arthrodesis


Valgus deformity



Triple Arthrodesis


Technique STJ Fusion


Subtalar ArthrodesisSubtalar Arthrodesis 2





- patient supine

- roll under hip to expose lateral aspect foot

- tourniquet, IV Abx, radiolucent table, II available




Direct lateral approach -  Tip of fibula toward base of 4th MT 

- internervous plane between SPN and sural nerve


Superficial dissection

- peroneal tendons lifted dorsally

- elevate EBD

- fatty tissue over sinus tarsi

- expose STJ / CCJ / sinus tarsi


Deep dissection

- remove TC interosseous ligament

- clear out sinus tarsi

- diathermy artery of tarsal sinus

- insert lamina spreader to expose posterior facet

- need to expose medial facet medially



- curette / osteotomes / burr

- simply remove cartilage if no deformity

- otherwise remove bone to correct deformity

- recreate 2 flat surfaces that come together in 5o valgus

- drill holes to stimulate bleeding +/- bone graft

- if previous calcaneal fracture, decompress lateral wall  

(5 - 10mm removed) 


Reduction technique in valgus foot



- talus internally rotated on calcaneum

- navicular abducted on talus



- need T Achilles lengthening

(assess at end) 

- need to perform TNJ and CCJ fusion

- likely need to have open reduced TNJ / CCJ before STJ reduction

- may need lateral bone block

- often deficient skin laterally



- reducing calcaneum back under talus difficult

- calcaneum also abducted like navicular

- lamina spreader between lateral process talus and anterior aspect of calcaneum

- open it up

- calcaneum internally rotates / talus externally rotates

- screw like motion

- need to have all joints opened and exposed for this to occur

- need care to ensure don't place foot into varus




Insert K wires for 6.5 mm/ 8.0 mm cannulated screw


- One or two from inferior calcaneum via stab incisions into body and neck of talus


Check position of K wires on II before screw insertion


Bone graft

- local usually sufficient

- if large correction take from proximal lateral or medial tibia  


TNJ fusion


Arthrodesis CCJ TNJ



- isolated TNJ OA (lose 80% subtalar joint motion)

- as part of triple arthrodesis


Midfoot Approach



- medial to T anterior, anterior to T posterior

- talar neck to naviculo-cuneiform joint

- protect saphenous nerve and vein

- Tibialis posterior guide to navicular



- can sometimes only expose 2/3 of joint medially

- may need to utilize the lateral approach for full exposure

- inserting lamina spreader aids exposure to debride

- reduce forefoot onto navicular by adducting /plantar flexing and pronating it

- must not leave in varus

- provisionally fix with K wires



- 2 x 4.0 mm cannulated screws

- from navicular into talus

- parallel or triangular 

- may need to make notch in medial cuneiform 


CCJ fusion



- exposed through continuation of lateral approach 



- 2 x screws

- must hug lateral border

- alternatively can use specific plates


T Achilles lengthening



- tight T Achilles

- if don't will have to take a lot of bone to get foot plantigrade



A.  Formal Z lengthen

B.  Hoke lengthening

- want to lengthen laterally more than medially

- 2 incisions halfway laterally

- 1 half incision medially between them

- stretch out the T Achilles



Back-slab for 2/52 

Wound inspection at 10 - 14/7

NWB in full cast for 4/52 

WBAT in walking cast for a further 6/52

6/52 radiologic assessment until union 

(pain-free WB with evidence radiologic union)