Workshop Outline. Pre-operative planning

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2 Workshop Objective To build and apply the True/Lok TM circular external fixator frame for correction of the Charcot forefoot deformity (Lisfranc fracture dislocation)

3 Workshop Outline Pre-operative planning

4 Workshop Outline Pre-operative planning Frame assembly Tibial double-ring block

5 Workshop Outline Pre-operative planning Frame assembly Tibial double-ring block Frame application Tibial frame Foot support Calcaneal fixation Adjustment block Metatarsals fixation

6 Workshop Outline Pre-operative planning Frame assembly Tibial double-ring block Frame application Tibial frame Foot support Calcaneal fixation Adjustment block Metatarsals fixation Frame adjustment Distraction Final acute correction

7 Final Construct

8 Each surgery should start with planning

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11 Preoperative Planning Choose the right size: Measure rings to fit the tibia Check foot plates on the patient for the heel and forefoot We are using 150mm rings and foot plate in this workshop 150mm

12 Preoperative Planning Use lateral foot x-ray

13 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis

14 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis Foot support axis 90

15 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis Foot support axis Foot support outline

16 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis Foot support axis Foot support outline Foot support for metatarsals

17 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis Foot support axis Foot support outline Foot support for metatarsals Tibial rings levels

18 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis Foot support axis Foot support outline Foot support for metatarsals Tibial rings levels Ring connection rod length

19 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis Foot support axis Foot support outline Foot support for metatarsals Tibial rings levels Ring connection rod length Tibia-foot connection rod length

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21 Preoperative Planning Use lateral foot x-ray Tibial mechanical axis Foot support axis Foot support outline Foot support for metatarsals Tibial rings levels Ring connection rod length Tibia-foot connection rod length Distraction rods length

22 Preoperative Planning

23 Preoperative stage

24 Parts 150-mm ring (2) 115-mm threaded rod (10) 150-mm foot plate (2) 80-mm threaded rod (1) 60-mm threaded rod (3) 1.8-mm smooth wire (2) 1.8-mm stopper wire (5) 5-mm half-pin (1) Wire fixation bolt (14) Half-pin fixation bolt (1) 1-hole post (3) Universal hinge (3) M6 s/s nut (50) Distraction nut (12)

25 Holds tibia & serves as a reference

26 Tibial Ring Block Assembly

27 Surgical stage

28 Frame Application Tibial ring block fixation Proximal horizontal wire Distal medial smooth wire Distal fibula-tibia olive wire Proximal half pin Calcaneus Fixation Foot plate connection 2 calcaneal wires Forefoot Fixation Adjustment block Foot plate Metatarsal olive wires

29 Good alignment is the key!

30 Proximal Tibial Wire Align frame with tibia Insert proximal tibial horizontal smooth wire, attach with 2 wire fixation bolts

31 Distal Tibial Wires Insert distal tibial wires One smooth through tibia only One olive through fibula and tibia Check Alignment Secure and tension both wires in distal ring Cut wire ends

32 Complete Proximal Tibial Fixation Tension and cut proximal tibial wire Insert a proximal tibial half pin perpendicular to the proximal tibial wire During half pin insertion, use fixation bolt as a guide After insertion, secure the shaft of the half pin to the proximal tibial ring

33 Holds rear foot secure with tibia

34 Connect Foot Plate Using 2 threaded rods connect foot plate to the tibial frame Adjust the level of the plate to align with the middle of calcaneus

35 Wires through Calcaneus Insert 2 olive wires from postero-medial and postero-lateral Be sure wires can be secured in the foot plate

36 Wires through Calcaneus Secure and tension wires in the foot plate Do not tension for more than 90kg Cut the ends of the wires

37 Build adjustment block and connect footplate to metatarsals

38 Building Adjustment Block Connect two 60mm threaded rods to 1-hole posts Insert rods into most anterior holes of the foot plate with posts facing down Use square distraction nuts to connect to the ring Finger-tight all connections

39 Building Adjustment Block Insert 115-mm threaded rod into each post Put square distraction nut on each side of the post Distraction Nut

40 Building Adjustment Block Attach universal hinges at the end of the rods Connect foot plate to the universal hinges Use next to the last holes to connect foot plate to the universal hinges Universal Hinges

41 Align Foot Plate with Metatarsals Align foot plate to the axis of the forefoot Secure all the connections tightly Tighten universal hinges on both sides Tighten distraction nuts Tighten rods connecting 1-hole posts Tighten!

42 Metatarsal Wires Insert medial metatarsal olive wire through metatarsals 1and 2 Insert lateral metatarsal olive wire through metatarsals Attach ends of both wires to foot support Tension and cut wires

43 Add another adjustment unit Add another adjustment unit between the top of distal foot plate and distal tibial ring Use 1-hole post Square distraction nuts 60-mm and 80-mm threaded rods Universal hinge Add adjustment unit

44 Frame is Ready for Correction

45 Gradual distraction and then acute final adjustment

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48 Distraction Start with linear distraction along 3 rods in the longitudinal direction Use double-wrench to adjust distraction nuts

49 Distraction Continue until 4-5 mm gap is created in Lisfranc joint

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51 Distraction Distract down at the tibial ring moving 3 1-hole post down reducing dorsal subluxation Continue until metatarsals are leveled with midfoot

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53 Acute Adjustment Loosen both ends of the universal hinges Acutely move the forefoot in correct position Loosen Loosen

54 Acute Adjustment Release all the distraction forces Continue fixation

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