Causes/Risk Factors
The most common demographic for Charcot Disease of the foot.
What are adults?
Commonly caused by S. aureus, this condition will not cause bony deformities or changes on imaging on the foot but will cause erythematous swelling in the foot.
What is cellulitis?
This muscle flexes the big toe and its primary attachment is the head of the fibula (worst bone in the body)
What is the flexor hallucis longus?
Common first symptoms of Charcot disease of foot
What is swelling of the affected area?
The boot individuals with Charcot disease of the foot will need to wear.
What is a CROW boot (Charcot restraint orthotic walker)?
Common risk factors for Charcot Disease of the Foot
What is diabetic neuropathy, trauma, alcoholism, and leprosy
Commonly caused by S. aureus, this will show increased inflammatory markers and unique MRI and bone scintigraphy findings.
What is osteomyelitis?
What is the most commonly sprained ligament in the foot?
Anterior talofibular ligament
The first imaging test a physician performs if they suspect Charcot disease of foot
What is an x-ray?
These are the commonly prescribed medications for an individual suffering from Charcot disease of foot.
What are bisphosphonates, neuropathic pain medications, antidepressants, and topical anesthetics?
These are other places Charcot disease can show up
What are the shoulders and knees?
Commonly caused by a buildup of urate crystals, this affliction commonly affects the big toe.
What is gout?
This is the distal attachment spot of the quadratus plantae muscle.
What is the tendon of the flexor digitorum longus?
What a physician orders if the x-ray is unclear (be specific) but still suspects Charcot
What is a MRI with gadolinium
This is the success rate of nonoperative treatments for Charcot disease of foot.
What is around 75%?
These are the common inflammatory cytokines that may cause destruction in Charcot disease of foot
What are IL-1 and TNF-alpha?
Commonly caused by the buildup of calcium pyrophosphate dihydrate crystals, this condition usually affects the knees and ankles.
What is pseudogout?
This nerve innervates the adductor hallucis muscle
What is the lateral plantar nerve?
The Semmes-Weinstein monofilament test number expected for an individual with Charcot disease of foot
What is 5.07?
This is the treatment that a physician will have to do if there has been failed previous surgeries and/or recurrent infections in a patient with Charcot disease of the foot.
What is amputation?
Daily Double #3
This question describes a patient with diabetic neuropathy and right foot Eichenholtz stage 3 charcot neuroarthropathy. Following total contact casting for a total of two to four months, patients with intact skin and without evidence of active infection may be placed in a charcot restraint orthotic walker (CROW) boot, and ultimately normal footwear with a double rocker sole modification.
Treatment for Charcot neuropathy depends on the stage and clinical presentation. The first-line treatment is nearly always total contact casting for a full two to four months followed by the use of a CROW boot. To offload areas of increased pressure, shoe modifications such as the double rocker sole, which decreases pressure from plantar midfoot prominences, are used in an effort to prevent future/worsening ulceration.
Janisse et al. described a variety of shoe modifications and orthoses for use in foot and ankle pathology. While several types of modifications were described, the authors noted the double rocker sole modification as the correct option for treating midfoot pathology.
Van der Ven et al. provide an expert opinion review presentation and management of charcot neuroarthropathy. The authors describe the typical progression of non-operative management (when indicated) including total contact casting for Stage 1 disease, followed by CROW boot use for Stage 2 disease, followed by appropriate accommodative footwear in Stage 3 disease.
Figure A demonstrates an example of total contact casting (a) and radiographic evidence of Eichenholtz stage 3 charcot neuroarthropathy (b).
Incorrect Answers:
Answer 1: (Figure B) - This figure shows a severe angle rocker sole which is helpful in reducing weight-bearing pressures distal to the ball of the foot (severe toe tip ulcerations)
Answer 2: (Figure C)- This figure shows a mild rocker sole, which provides a rocking mechanism at the heel and toe to produce mild metatarsal head relief and to assist in gait via forward propulsion.
Answer 4: (Figure E)- This figure shows a negative heel rocker sole, which forces the heel height to be lower than that of the ankle, and is designed both for patients with fixed dorsiflexion and for patients with forefoot pressures as this sole transfers pressure to the midfoot and heel.
Answer 5: (Figure F)- This figure shows a heal-to-toe rocker sole, which is helpful in assisting with gait by increasing propulsion at toe-off; this modification is helpful for patients after ankle/subtalar fusion or patients with fixed lesser toe deformities (hammer, claw toes).
Daily Double #4
This is a classic presentation of Charcot arthropathy in a diabetic patient after sustaining a relatively minor trauma. In addition, hyperemia that regresses with elevation is classic for Charcot. Neuropathy has the greatest affect on diabetic foot pathology and the most sensitive test is the Semme's Weinstein monafilament testing.
Guyton et al's ICL on the diabetic foot presents a comprehensive review of this topic.
Daily Double #5
This patient is presenting with Charcot arthropathy, a known complication of diabetes mellitus. Clinical photograph and radiographs show the characteristic appearance of the Charcot foot with complete arch collapse and multi-joint end stage degenerative joint disease through the entire hind, mid, and fore-foot.
As described by Guyton and Saltzman, there is a complex pathophysiology by which diabetes contributes to the foot deformities seen in Charcot arthropathy. This pathophysiology includes alterations in peripheral nerves, bones/soft tissue, gait kinematics, microscopic/macroscopic vascularity, immune system, and mechanisms of wound healing. To treat, one must address the mechanical and biologic aspects of the disease.
Daily Double #2
The clinical presentation is consistent with a diabetic associated Charcot neuroarthropathy that has failed conservative management with total contact casting. Given the presence of a bony projection, in the setting of a stable deformity, exostectomy is a reasonable option. An equinus contracture is indicative of a tight Achilles tendon and as such a lengthening is warranted.
The first line of treatment of Charcot arthropathy is conservative measures; total contact casting is the gold standard. Surgical intervention may be considered in patients for whom ulceration persists despite total contact casting. Increasing deformity, with evidence of joint instability is another indication for surgery. For this patient, who does not appear to have evidence of major instability on examination, the preferred treatment is an exostectomy with protective bracing. The Silverskiold test, which differentiates between a tight gastrocnemius muscle vs. a tight Achilles tendon complex, can be used to determine if what kind of lengthening procedure should be considered. With a positive Silverskiold test, the gastrocnemius is tight. For this patient, an exostectomy can be combined with an Achilles lengthening to help prevent ulceration in the forefoot.
Van der Ven A et. al review the current concepts for evaluation and management of Charcot arthropathy. The article delineates that ulceration is often the result of malpositioning of tarsal bones after joint collapse. Chronic ulceration that fails to resolve with conservative measures (i.e. contact casting) can be managed with exostectomy and protective bracing, with successful limb salvage in up to 90%. Concomitant Achilles tendon lengthening should be considered for those with contracture in the setting of recurrent plantar ulceration.
Figure A demonstrates an ulcer commonly identified in the midfoot region as a result of Charcot arthropathy. Figure B shows a lateral x-ray of a patient with radiographic evidence of midfoot joint collapse with soft tissue abutment.
Illustration A demonstrates the Silverskiold test; passive dorsiflexion is completed with knee in flexion & extension to differentiate between Achilles tendon tightness or gastrocnemius tightness.
Incorrect Answers:
Answer 1: External Fixation would not address this problem.
Answer 2: At this time the patient has viable tissue and an amputation is not indicated.
Answer 3: Observation would not be indicated as this patient is having persistent ulceration that has not resolved with conservative measures.
Answer 4: As this patient has an equinus contracture he will require a lengthening procedure as well.
Daily Double #1
This patient has Charcot diabetic neuroarthropathy with ulceration over the talar head. Reduction of the uncovered talar head is necessary to relieve soft tissue tension and allow the ulcer to heal. Stabilization and bony fusion with an external fixation device such as a ring fixator helps prevent recurrent dislocation and ulceration, while avoiding hardware placement around the ulcer. It also allows easy monitoring of soft tissue healing.
Charcot arthropathy is managed primarily with offloading and immobilization. Surgery is indicated for resecting osteomyelitic bone and bony prominences and correcting unstable deformities that could not be successfully accommodated with therapeutic footwear, custom AFO or a CROW walker.
Rogers et al. reviewed the evaluation and management of Charcot foot in diabetes. They report indications for surgery include cases refractory to offloading and immobilization, recalcitrant ulcers, or severe Charcot neuropathic arthropathy of the ankle. They discuss the various treatment options including exostectomy, Achilles tendon lengthening and arthrodesis.
Pinzur (Aug 2007) reviewed the management of Charcot arthropathy. He recommends total contact casting for early stage arthropathy, and commercially available depth-inlay shoes with accommodative orthoses or rocker-bottom shoes combined with an AFO or CROW for late stage arthropathy. He recommends operative intervention for persistent plantar ulceration that cannot be managed nonoperatively, and unstable Charcot ankle arthropathy.
Pinzur et al (July 2007). reviewed surgical stabilization of the non-plantigrade Charcot foot. They recommend surgical stabilization for non-plantigrade feet with non-colinear talar-1st metatarsal axis on weightbearing radiographs. They recommend plates and screws for good hosts with good quality bone, and ring fixators for poor hosts with poor quality bone.
Figure A is a clinical photograph showing abduction deformity and rocker-sole deformity of the foot, with ulceration over the uncovered talar head. Figure B comprises lateral and AP radiographs of Brodsky type 2 Charcot neuroarthropathy involving the subtalar and talonavicular joints. There is chronic ulceration and osteomyelitis centered around the exposed talar head. Illustration A shows correction of this deformity with a ring fixator.
Incorrect Answers
Answer 1: In the face of failed repeated offloading (CROW or total contact casting), another course of such treatment is contraindicated. Further offloading will not prevent recurrent ulceration.
Answer 2: Achilles lengthening may address equinus contractures, but lengthening alone will not correct talar head extrusion and ulceration.
Answer 3: TTC fusion is useful for Brodsky Type 2-3 deformities. However, reduction and correction of the deformity is necessary to create a plantigrade foot and to prevent ulcer recurrence. In-situ fusion is contraindicated.
Answer 4: Midfoot osteotomy is used to address Brodsky Type 1 deformities involving the midfoot Lisfranc joints, but is not useful for deformities about the Chopart joints/subtalar joints. Plates and screws are contraindicated in the presence of poor quality host bone and visible ulceration.