1. Ankle deformity and arthritis
Case for small group discussion
AOTrauma—Foot & Ankle
Module 7: Ankle arthritis
Christina Kabbash, US

2. Case description 46-year-old man
Right rigid cavus ankle deformity, no trauma, history of Lyme disease with arthralgia and spine involvement
Builds submarines

3. Case description Ankle ROM: 5° Subtalar ROM: 0°
No hindfoot pain after ankle injection with local anesthetic
No neuropathy
Nonsmoker; no diabetes
Next step: infection workup

4. Preoperative AP/mortise x-ray
Need to restore the mechanical axis with the calcaneus under the knee (lateralization)
Need to correct the heel varus
Need to bone graft the cysts

5. Preoperative lateral x-ray
Need to restore the mechanical axis with the calcaneus under the knee (lateralization)
Need to correct the heel varus
Need to bone graft the cysts
Cultures at time of surgery!!!

6. Infection work-up
Erythrocyte sedimentation rate (ESR), C-Reactive Protein Test (CRP), Bone scan 99Tc, and 111Indium negative for osteomyelitis
CT-guided bone biopsy negative for osteomyelitis
CT showed bony cysts at the tibiotalar joint and moderate arthritis at the subtalar joint

7. Rheumatology work-up
Lyme titer 1.3 (3.3 prior to IV treatment for spine involvement)
Immunoglobulin (IgG and IgM) positive
No contraindications for surgery

8. Treatment options? Bracing Fusion Total ankle replacement
Bracing: rigid deformity—unable to restore mechanical axis
Total ankle: significant loss of bone stock with cysts; significant varus deformity

9. Fusion options External fixation Screws Plates and screws
Hindfoot arthrodesis nail (TTC fusion)
Arthroscopic
Considerations: good soft-tissue envelope present, need to be able to correct severe deformity and bone graft cysts
External fixation and TCC: overkill
Arthroscopic : not powerful enough

10. ORIF approaches Anterior Transfibular Posterior
Considerations: good soft-tissue envelope present, need to be able to correct severe deformity and bone graft cysts
External fixation and TCC: overkill
Arthroscopic: not powerful enough

11. 2 weeks postoperative
Did not fully correct varus since the hindfoot was rigid
Fibula bone graft used for cysts and for vascularized strut
Hindfoot was rigid but no painful, so not fused

12. 8 months postoperative

13. Preoperative
8 months postoperative
Left ankle

14. Preoperative
8 months postoperative
Left ankle

15. Take-home messages Always rule out infection
Choose the proper surgical approach for the case considering soft-tissue envelope, bone stock, and fixation technique
Advantages of transfibular approach:
Excellent exposure for debridement of talar dome and even posterior subtalar joint
Fibula provides morselized and live bone graft