Operative Care Stage 3 and 4 PTTD

Selene G. Parekh, MD, MBAAssociate Professor of Surgery

Partner, North Carolina Orthopaedic ClinicDepartment of Orthopaedic Surgery

Adjunct Faculty Fuqua Business SchoolDuke University

Durham, NC919.471.9622

http://seleneparekhmd.comTwitter: @seleneparekhmd

Stage 3 and 4 PTTD

• Stage 3• Rigid flat foot deformity

• Stage 4• Rigid foot deformity with ankle arthritis

Introduction• Triple arthrodesis

• Fusion of the three hindfoot articulations• Subtalar or talocalcaneal• Talonavicular• Calcaneocuboid joints.• Responsible for

• Supination and pronation of the foot;

Indications• Goal

• Achieve a stable, painless, and plantigrade foot.

• When possible, a procedure that preserves normal hindfoot motion and mechanics should be considered.

• In instances where this would be inappropriate• Triple arthrodesis valuable salvage procedure.

Hindfoot ArthritisSubtalar/Talonavicular/Calcaneocuboid

COUPLED MOTION• Talonavicular

• 6 degrees of freedom• Ab/adduction forefoot• Varus/valgus forefoot• Dorsiflexion/plantarflexion

Hindfoot ArthritisSubtalar/Talonavicular/Calcaneocuboid

• Talonavicular• 6 degrees of freedom

• Ab/adduction forefoot• Varus/valgus forefoot• Dorsiflexion/plantarflexion

Hindfoot ArthritisSubtalar/Talonavicular/Calcaneocuboid

• Subtalar • Inversion/eversion

• Calcaneocuboid• Dorsiflexion/plantarflexion• Ab/adduction

Hindfoot Arthritis Presentation

• History• Trauma: Calc., talus fx, disloc.• Inflammatory arthritis

• Pain location “One Finger”• Sinus tarsi (subtalar)• Just below ankle (T-N)

• Swelling• Malalignment

• Flatfoot, Cavus foot• Antalgic gait

Hindfoot Arthritis Presentation

• Swelling• Tenderness• Decreased inversion/eversion motion• Crepitus• Malalignment

Hindfoot Arthritis Radiographs

• Radiographs• Standing A/P, Lateral and Oblique foot• Standing A/P ankle• Possibly axial heel view (Harris)

Hindfoot Arthritis Radiographs

• Radiographs• Standing A/P, Lateral and Oblique foot• Standing A/P ankle• Possibly axial heel view (Harris)

Hindfoot Arthritis PE and Radiographs

• Possibly (rare)• CT scan for Coalition/Assess degree of arthritis of

adjacent joints

Hindfoot Arthritis: Non-op Treatment

• Non-operative– Lose Weight (5lbs = 20lbs foot)– Activity Modification

– Biking– Swimming

– NSAIDS– Glucosamine

– AAOS position paper said as effective as ibuprofen

– Bracewear– Cortisone injection AND Bracewear

Hindfoot Arthritis Non-op Treatment

• Non-operative• Stiff Shoe Heel Counter

– Bracewear• Decrease motion• Shift load

• OTC Ankle brace• Custom Ankle brace

• Arizona, Richie• University of California Biomechanics Laboratory (UCBL)• AFO +/- anterior clamshell

Ankle Brace

Preoperative Evaluation• All patients should have adequate circulation.

• If pedal pulses are not palpable• Arterial Doppler evaluation for ankle brachial

indices, dorsalis pedis indices and normal wave forms should be performed.

Preoperative Evaluation• Sensation should be documented preoperatively

• The presence of peripheral neuropathy must be identified to avoid potential complications of postoperative Charcot arthropathy.

Preoperative Evaluation• A complete understanding of the relationship

between the forefoot and hindfoot in supination and pronation deformities of the foot is essential for proper positioning of triple arthrodesis.

Preoperative Evaluation• Pes planus deformity - a pronated foot

• Heel in valgus

• Forefoot is both abducted at TN jt and in varus

• Proper positioning of the foot at surgery• Heel - five degrees of residual valgus• Forefoot abduction - bringing the navicular

medially cover the head of the talus• Can be assessed by palpation of the medial

side of the foot at the talonavicular joint to identify any residual subluxation.

Preoperative Evaluation• Long standing pes planus deformities

• Secondary contracture of the GSC

• Assessed by reducing the talonavicular joint to neutral and then dorsiflexing the ankle

• If contracture present • TAL• Recession

Preoperative Evaluation• Valgus angulation of talus in the ankle

mortise suggestive of deltoid ligament insufficiency

• May promote degenerative arthritic changes in the ankle joint following triple arthrodesis secondary to increased load on the lateral portion of the joint.

Case

Case

Surgical Technique• Multiple techniques

• Basic principles• Surgical incisions placed to avoid injury

to the sensory nerves of the dorsum of the foot

• Anatomic realignment • Hindfoot to 3-5 degrees of residual

heel valgus• Neutral alignment of the forefoot

Surgical Technique• Preparing joint surfaces

• Remove all the residual cartilage and subchondral bone to the level of exposed cancellous surfaces

• Rigid fixation with compression of the joint surfaces• Maintain corrected position• Promote fusion

• Bone graft needed if significant bony defect

Lateral Incision

• Tip of fibula to base of the 4th

• Careful of sural

Lateral Incision

• Final peroneals and trace distally to CC jt

• Elevate extensors of anterior process

• Enter subtalar and CC jts

• Prepare joints

Medial Incision

• Between ATT and PTT

• Inferior to saphenous vein

Medial Incision

• Open capsule

• Distract joint

• Prepare joint

Joint Preparation

Position

• Take the heel out of valgus• Pin from neck to calcaneus• Place hardware

• Reduce TN joint• Correct abduction and supination• Place hardware

• Place hardware over CC joint

Stage 4

• Ankle arthritis• Ankle fusion

• At same time• Pantalar fusion with TTC rod

Stage 4

• Ankle arthritis• Ankle replacement

• Staged by 4-6 wks

Post-operative Management• NWB in a compressive dressing with plaster splints

• 10-14 days

• NWB in SLC 2-4 wks• X-rays at six weeks demonstrate adequate bony

healing, immobilize in a walking cast/boot for an additional eight to ten weeks

• Immobilization is continued until there is radiographic evidence of solid union with consolidation of the fusion sites

Complications• Malalignment

• Significantly increase the forces on the ankle joint

• Excessive hindfoot valgus• Increase the stress on the deltoid

ligament by as much as 76% increasing force across the ankle joint

• May lead to continued lateral subfibular impingement and continued lateral pain

Complications

Complications• Residual hindfoot varus

• Cause overload of the lateral column of the foot causing pain at the cuboid or base of the fifth metatarsal

• Lead to lateral ankle instability and secondary ankle arthritis

Complications• Significant residual varus or valgus of the

forefoot• Abnormal gait pattern • Cause excessive forces across the ankle

joint• May require revision of the triple arthrodesis

• Extensive calcaneal varus or valgus of the calcaneus • Corrected by utilizing a Dwyer type

calcaneal osteotomy

Complications

• Loss of motion remains a problem• Produces secondary arthrosis of the ankle and tarso-

metatarsal joints over time• These changes are often not apparent clinically• Radiographic changes have been reported in over

fifty percent of patients

• This problem remains unsolved and the long term implications unclear

Complications• Nerve injury or entrapment of the sural nerve at the

lateral incision

• Require a neurolysis or nerve resection if the symptoms become severe

Complications• Failure to address an Achilles Tendon contraction

• Lead to excessive midfoot stresses

• Lengthened to achieve no more than 10 degrees of dorsiflexion

Complications• Secondary degenerative arthritis of the ankle

and midfoot reported 14-20%• More common with residual malalignment

• Ankle symptoms can often be treated with the use (MAFO)

• Midfoot pain can be treated with a UCBL

• If bracing unsuccessful• Consider fusion/replacement of these

effected joints

Complications• Avascular necrosis of the talus reported

• If present and symptomatic• Initial treatment employ bracing

• Unsuccessful then consideration of ankle fusion

Complications• If a triple arthrodesis is being done as a stage

procedure for a later total ankle or as part of a pan-talar arthritis then a limited subtalar fusion should be considered

• Only the posterior facet should be approached

• Do not violate the arterial supply of the talus from the inferior neck

Complications• Nonunions occur

• TN joint• Theorized to stem from inadequate

exposure and preparation of the joint surfaces

• If nonunion is asymptomatic no treatment is required

• If nonunion produces symptoms then revision of the nonunion with internal fixation and bone grafting is generally effective

RE ECT

the ankle

the foot