Midfoot
A. Lis Franc Joints OA
May cause flat foot
Treat with midfoot fusion
B. TNJ OA
May be affected in isolation early
- may cause passively correctable valgus foot
- UCBL insert
Talonavicular Arthrodesis
Indication
- erosion confined to this joint
- correct valgus deformity
Technique
- dorsomedial incision
- protect saphenous nerve and vein
Result
- will lose 80% STJ motion
Hindfoot
A. Tendo Achilles Insertional Tendonitis
Rheumatoid involvement of bursa at T Achilles insertion
- nodules may develop within the tendon
- can weaken attachment & precipitate rupture
Treatment
- excision of nodules
- may need tendon augmentation / reconstruction
B. Retrocalcaneal Bursitis
Common
- heel lift initially
- may need debridement and excision of posterosuperior calcaneal prominence
C. Tibialis Posterior Tendonitis / Rupture
Synovitis of sheaths of T post & Peroneal tendons common
- treat with tenosynovectomy
Rupture of TP with flatfoot
- FDL transfer in Stage 2
- triple arthrodesis in Stage 3
- pan talar arthrodesis in Stage 4
D. Planovalgus
Causes
- STJ OA
- TNJ OA
- tibialis posterior rupture
- synovitis and rupture of the talocalcaneal interosseous ligament
- tight T Achilles
Pathology
- subtalar joint valgus angulation
- talar head drops into plantarflexion
- navicular subluxes laterally
- get planovalgus foot with forefoot abduction
Non Operative
Brace
- double upright with square ferrule
Operative
Triple Arthrodesis
Indication
- fixed painful hindfoot
- TNJ and STJ OA
- AKJ preserved
F. AKJ OA
Total Ankle Replacement
Attractive concept
- reduces loading across other joints
- results similar to OA
Ankle Arthrodesis
Treatment of choice
Complicated by
- prolonged period to union - 6/12
- non-union in 10%