treatment of the rheumatoid foot

general

· most commonly involves forefoot

· 10x more common than hindfoot

· common deformities

· hallux valgus

· dorsal subluxation of MTP joints

· clawing of toes

· in midfoot, most often involves talonavicular jt

· less commonly involves subtalar joint

· may affect ankle joint

· destruction of talonavicular and subtalar joints leads to planovalgus foot

· may be initiated or exacerbated by rupture of tibialis posterior

Ankle

· rarely affected in isolation

tendon involvement

Tendo Achilles

· rheumatoid involvement of bursa at tendo Achilles insertion can weaken attachment and precipitate rupture

· nodules may develop within the tendon

· may lead to rupture

· treatment is excision of nodules

Tendon sheaths

· synovitis of sheaths of tibialis posterior and peroneal tendons common

· treated with tenosynovectomy

· may precipitate rupture of tibialis posterior with flatfoot

· treated with FDL transfer

Synovitis

· not common before subtalar and midtarsal jts affected

· causes pain, swelling and effusions

· synovectomy gives good results

· through medial and lateral approaches

destroyed ankle

· rarely occurs in isolation

Brace

· double upright with square ferrule

· patellar-bearing brim to reduce stress on ankle

· SACH

· solid ankle cushion heel

· wedge compresses on heel strike and simulates ankle plantarflexion

Total ankle replacement

· attractive concept because would reduce loading across other joints

· long-term results poor

Ankle arthrodesis

· treatment of choice

· complicated by

· prolonged period to union - 6 months

· nonunion in 10-20%

· extra strain on other joints

Tarsal joints

Talonavicular involvement

· talonavicular joint may be affected in isolation early

· may give passively correctable valgus foot

Insert

· if flexible, UCBL insert

Talonavicular arthrodesis

· if erosion confined to this joint

· may correct valgus deformity

hindfoot involvement

· talonavicular involvement usually progresses to involve subtalar and calcaneocuboid joint

· result is fixed planovalgus foot

Triple arthrodesis

· for fixed painful hindfoot

· aim to produce plantigrade foot

Forefoot

· most commonly affected

metatarsalgia

· earliest manifestation is synovitis of MTP joints

· capsular destruction leads to dorsal subluxation of toes on MT heads

· intrinsics unable to flex MTP jts

· claw toes develop

· plantar fat pad displaced distally

· MT heads exposed to plantar skin

· corns develop over PIP jts and under MT heads

Nonoperative

Shoewear modification

· extra-depth shoe with low heel and roomy toebox

· custom-made arch support with

· metatarsal bar for metatarsalgia

· heel cup to prevent heel valgus

Operative

· indications

· continuing pain

· increasing deformity

· exasperation with unattractive footwear

· effective in 80-90%

· problems with

· poor wound healing

· infection

· nonunion

· recurrence of deformity

Metatarsal osteotomy

· for painful callosity under one or two MT heads

· if 2 or more MTP jts dislocated, all 4 should be treated

Forefoot reconstruction

· in form of

· arthrodesis of hallux MTP jt

· cascading excision of lesser MT heads

· resection of heads of proximal phalanx

· dorsal approach

· multiple longitudinal incisions

· if deformity mild

· easy access wtihout concern for NV bundles

· plantar approach

· transverse ellipse

· if deformity severe

· MT heads prominent and NV bundles subluxed dorsally

hallux valgus

· great toe often develops hallux valgus

· ofen associated with planovalgus foot

Arthodesis

· procedure of choice

· provides forefoot power and buttresses lesser toes

· contraindications

· involvement of IP joint

· complications

· nonunion

· malposition

· stress transfer to IP jt

Silicone arthroplasty

· double-stemmed Swanson prosthesis

· indications

· low-demand patient

· IP joint of hallux affected

· complications

· breakage

· silicone synovitis

Kellers procedure

· indications

· low-demand patient where bony union expected to be difficult

· as salvage procedure

· complications

· transfer metatarsalgia

· loss of power

Multiple joint surgery

· start with forefoot

· great symptomatic relief

· minimal patient stress

· eliminates pedal sepsis

· wound problems common and occur before prostheses implanted

· then hip replacements

· easier to rehabilitate following THR with deformed knees

· allows correction of proximal limb contractures and lordosis

· then total knee replacements

· then hindfoot surgery