Skip to content

Patients › Foot

Pé cavo

Updated Sep 2026
Illustration: foot

Esta página foi traduzida automaticamente e ainda não foi verificada por um médico. A versão em inglês é a versão oficial.

O que você está sentindo

O pé cavo possui um arco muito elevado. O principal problema é que a parte da frente do pé fica inclinada para baixo, em direção ao chão. Para manter a parte externa do pé em contato com o solo, o calcanhar se inclina para dentro. Com o tempo, a espessa faixa de tecido na sola do pé se torna mais tensa, e o calcanhar fica mais rígido nessa posição inclinada.

Você pode sentir dor na parte da frente do tornozelo. Como a frente do pé aponta para baixo de forma acentuada, o tornozelo precisa se dobrar para cima mais do que o normal para manter o pé na horizontal. Quando esse movimento atinge seu limite, os ossos na parte frontal do tornozelo pressionam uns contra os outros, causando dor.

Você também pode notar áreas de pele endurecida e sensível sob a base dos dedos, sob o dedão do pé e ao longo da borda externa do pé. Essas calosidades se formam porque o peso do corpo é concentrado em pequenas áreas em vez de se distribuir uniformemente. Ficar em pé ou caminhar por longos períodos pode tornar essas áreas ainda mais doloridas. Os pequenos músculos internos do pé frequentemente atrofiam, e os dedos podem se curvar ou ficar em garra para baixo. Essa garra faz com que os sapatos causem atrito, dificultando a busca por calçados confortáveis.

Muitas pessoas com esse formato de pé sentem instabilidade. O tornozelo pode “ceder”, e é comum torcê-lo em terrenos irregulares ou ao descer de um meio-fio. Entorses repetidas, dor ao longo da parte externa do tornozelo e pequenas fissuras nos ossos do pé podem surgir devido à forma como o peso corporal é transferido para a borda externa do pé.

Essas alterações geralmente afetam ambos os pés, embora um lado possa ser mais afetado que o outro. Como esse formato de pé costuma ser hereditário e pode estar ligado a problemas neurológicos ou musculares, o cirurgião perguntará sobre seu histórico familiar e examinará os nervos das pernas. Se apenas um pé for afetado, exames de imagem da coluna vertebral podem ser necessários para identificar a causa. Radiografias do pé e do tornozelo em carga mostram o grau de elevação do arco e se o calcanhar ainda mantém flexibilidade.

O que está realmente acontecendo

Pense no seu pé como um tripé. Um pé saudável apoia-se em três pontos: o calcanhar, a parte anterior sob o dedão do pé e a parte anterior sob o dedo mindinho. No pé cavo, a parte dianteira do pé desce demais, especialmente sob o dedão. Para manter a parte externa do pé em contato com o chão, o calcanhar precisa inclinar-se para dentro. Assim, o peso do corpo desce por uma das bordas do tripé, em vez de ser distribuído entre os três pontos.

Essa queda da parte dianteira do pé geralmente começa com os pequenos músculos internos do pé. Quando eles ficam fracos ou tensos, deixam de equilibrar os músculos mais fortes da panturrilha e da perna. A faixa de tecido tenso na sola do pé eleva cada vez mais o arco plantar, pressionando os ossos longos dos dedos contra o chão. Com esse desequilíbrio muscular, o calcanhar inclina-se para dentro e os dedos do pé curvam-se e ficam em garra.

Essa forma do pé raramente aparece isoladamente. Geralmente é sinal de alguma condição nervosa ou muscular subjacente; na maioria das vezes, trata-se da doença de Charcot-Marie-Tooth, que afeta os nervos que vão até os músculos. Cerca de dois terços das pessoas com pé cavo têm uma condição desse tipo. Aproximadamente uma em cada dez pessoas apresenta esse formato do pé em algum grau, sendo que a maioria nunca apresenta sintomas. É raro aparecer em crianças pequenas, mas torna-se bastante comum após os 8 a 10 anos de idade.

Todos os sintomas que você sente decorrem desse desequilíbrio. A queda da parte dianteira do pé obriga o tornozelo a dobrar-se para cima além do limite normal, provocando dor na região anterior do tornozelo. O peso do corpo sobre a parte anterior do pé e a borda externa gera calosidades. O calcanhar inclinado torna o tornozelo instável e propenso a torções. Mesmo uma forma leve desse pé pode levar a entorses recorrentes, rupturas dos tendões na lateral do tornozelo e pequenas fraturas nos ossos do pé.

O que podemos fazer a respeito

Os tratamentos mais simples visam relaxar as áreas tensas e fortalecer as áreas fracas. O alongamento do tendão de Aquiles, o forte cordão na parte de trás do tornozelo, é uma medida fundamental. A fisioterapia também trabalha no fortalecimento dos músculos responsáveis por levantar o pé e girá-lo para fora. Para um pé levemente deformado, flexível e sem dor, esse programa pode ser tudo o que você precisa. Mudanças nos sapatos e o uso de palmilhas podem distribuir melhor o peso e aliviar pontos de pressão, embora não corrijam a deformidade do arco em si. Sapatos de corrida neutros e acolchoados reduzem a carga sob a sola, caso você seja ativo fisicamente. Se os seus dedos estiverem em garra, uma simples tala que os mantém retos pode melhorar a marcha sem prejudicar a pele. Em crianças com deformidade do pé de origem neurológica, essas medidas podem adiar a cirurgia por anos; em cerca de metade das crianças acompanhadas até o fim do crescimento, a cirurgia acaba não sendo necessária. Dê ao tratamento não cirúrgico uma chance justa antes de decidir por qualquer outra medida.

Não utilizamos cortisona nem outros tipos de injeções para essa condição, portanto não as oferecemos. Para a condição neurológica que muitas vezes está na base dessa deformidade do pé, as injeções de toxina botulínica são seguras e bem toleradas, porém não retardam a evolução da deformidade do arco. O uso de gessos sucessivos também não surtiu efeito, e altas doses de vitamina C não alteram o quadro clínico.

A cirurgia entra em pauta quando o seu pé fica doloroso, rígido ou piora apesar das medidas acima. Nosso objetivo é manter a mobilidade das articulações sempre que possível. Isso pode envolver o afrouxamento dos tecidos tensos na sola do pé, o deslocamento de tendões para reequilibrar o pé ou o corte e remodelação dos ossos para reduzir a deformidade do arco. Se o seu calcanhar ainda for flexível, preferimos cirurgias que preservam as articulações. Quando o pé está muito rígido e gravemente deformado, ou quando as articulações já estão desgastadas, a fusão de algumas articulações pode ser a única opção restante. Conversaremos sobre o que cada procedimento implica e decidiremos juntos qual é a melhor escolha para o seu pé e para os seus objetivos.

O que esperar

O pé cavo é uma condição de longa data, não uma doença passageira. Ele não aparece e desaparece. Sem cuidados adequados, o arco plantar tende a permanecer elevado ou a ficar ainda mais alto, e o calcanhar tende a ficar rígido em sua posição inclinada. Os problemas que você sente atualmente, como dor na região da base dos dedos, entorses de tornozelo e dedos em garra, geralmente persistem ou pioram gradualmente, em vez de desaparecerem por conta própria.

Os tratamentos não cirúrgicos podem realmente alterar esse curso. Alongamentos, exercícios de fortalecimento, troca de calçados e o uso de palmilhas ajudam a aliviar a pressão e a melhorar o funcionamento do pé. Em crianças com problemas neurológicos que causam o pé cavo, essas medidas podem adiar a cirurgia por anos; em cerca de metade das crianças acompanhadas até o fim do crescimento, a cirurgia acaba não sendo necessária. Mesmo quando a cirurgia se torna inevitável, ela costuma ser adiada em cerca de 4,5 anos. Contudo, essa forma do pé geralmente não desaparece. O objetivo de um bom tratamento é manter o pé confortável, estável e capaz de desempenhar suas funções pelo maior tempo possível.

Quando a cirurgia é indicada, o prognóstico depende da flexibilidade do pé e da gravidade das alterações. Procedimentos que preservam as articulações são preferidos sempre que possível; eles são adequados para a maioria dos pés flexíveis, inclusive para aqueles afetados pela doença de Charcot-Marie-Tooth. Essas cirurgias visam diminuir o arco plantar mantendo a mobilidade articular. Para pés muito rígidos ou com articulações danificadas, pode ser necessário fundir algumas articulações, sendo essa geralmente reservada como última opção. A maioria das pessoas submetidas à correção de um pé cavo grave consegue retornar ao trabalho e relata melhoria na qualidade de vida posteriormente.

É importante conhecer alguns limites reais. A cirurgia não resulta em um pé “normal”. O objetivo da correção é distribuir melhor o peso corporal, estabilizar o tornozelo e facilitar o uso de calçados. Alguns procedimentos melhoram bastante a distância percorrida ao caminhar, a capacidade de atividade física e o uso de calçados, porém têm menor efeito sobre a dor. Como a condição neurológica ou muscular subjacente geralmente persiste, a forma do pé pode mudar novamente com o tempo; por isso, o acompanhamento contínuo é essencial.

Quando procurar ajuda médica

Consulte seu médico de família se notar que o arco do pé está ficando cada vez mais alto, se calos continuam a aparecer na parte anterior do pé ou na borda lateral, se os dedos começam a se curvar ou a ficar em forma de garra, ou se ocorrem entorses de tornozelo repetidamente. Solicite uma avaliação por um especialista se sentir dor na frente do tornozelo ao caminhar ou subir escadas, se o tornozelo “ceder” com frequência em terrenos irregulares, ou se o pé está ficando rígido e os sapatos passam a não servir mais. Como esse formato do pé costuma ser sinal de algum problema neurológico ou muscular, mencione se há histórico familiar de pés semelhantes, fraqueza nas pernas ou perda de sensibilidade nos pés. Procure o pronto-socorro se surgir fraqueza súbita, dormência ou perda do controle da bexiga ou do intestino, pois isso pode indicar um problema na medula espinhal que requer avaliação no mesmo dia.


Evidence & references

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview

  • A pes cavus (cavus foot) is characterized by an elevated medial longitudinal arch secondary to forefoot plantar flexion [1].
  • A pes cavus (cavus foot) may also result from excessive calcaneal dorsiflexion, though this is less frequent than forefoot plantar flexion [1].
  • Two-thirds of patients with a cavus foot have an underlying neurologic disorder [1].
  • Charcot-Marie-Tooth disease is the most common underlying neurologic disorder in patients with a cavus foot [1].
  • The primary structural problem in cavus foot is forefoot plantar flexion [1].
  • The first ray is often more markedly plantarflexed than other rays, resulting in forefoot pronation [1].
  • For the lateral half of the foot to contact the ground, the hindfoot must deviate into varus [1].
  • First ray plantar flexion may result from a weak tibialis anterior relative to the peroneus longus [1].
  • First ray plantar flexion is more commonly caused by intrinsic weakness and contracture than by tibialis anterior weakness [1].
  • Over time, the plantar fascia contracts, causing the hindfoot varus deformity to become more rigid [1].
  • Patients with cavus foot may report instability, such as ankle sprains [1].
  • A neurologic examination and family history are essential for evaluating cavus foot [1].
  • Unilateral involvement suggests a focal diagnosis, such as a spinal cord anomaly or nerve injury [1].
  • Bilateral involvement and a positive family history are common with Charcot-Marie-Tooth disease [1].
  • Asymmetry may be seen in Charcot-Marie-Tooth disease despite bilateral involvement [1].
  • Hindfoot flexibility is assessed by placing a 1-inch block under the lateral border of the foot (Coleman block test) [1].
  • Weight-bearing radiographs are required for the evaluation of cavus foot [1].
  • An increased Meary angle is defined as the long axis of the talus intersecting the long axis of the first metatarsal dorsally on the lateral view of the foot [1].
  • The normal value for the Meary angle is 0° to 5° [1].
  • An increased calcaneal pitch is defined as the intersection of a line running along the undersurface of the calcaneus and the floor [1].
  • A calcaneal pitch greater than 30° indicates a calcaneocavus foot [1].
  • MRI of the spine is indicated with unilateral involvement [1].
  • Joint-sparing procedures are preferred whenever possible for the treatment of cavus foot [1].
  • The flexibility of the hindfoot is a key factor in surgical decision making for cavus foot [1].
  • Percutaneous plantar fascia release is insufficient to correct a cavus foot [1].
  • At minimum, an open release and soft-tissue rebalancing are needed to correct a cavus foot [1].
  • Achilles tendon lengthening should not be performed concomitantly with plantar fasciotomy [1].
  • An intact Achilles tendon provides the resistance necessary to stretch the contracted plantar tissues and correct the cavus deformity [1].
  • In a non-weight-bearing position, the long axes of the tibia and the calcaneus are parallel in a cavus foot [1].
  • In a weight-bearing position, a rigid equinus forefoot deformity forces the flexible hindfoot into varus, creating a tripod effect [1].
  • For mild, flexible, and painless cavus foot, treatment includes Achilles tendon stretching and an eversion/dorsiflexion strengthening program [1].
  • For mild, progressive or symptomatic cavus foot, treatment includes plantar release with or without peroneus longus to brevis transfer [1].
  • For varus caused by peroneal weakness, treatment includes adding tibialis anterior and/or posterior tendon transfer to the peroneal muscles [1].
  • For moderate rigid medial cavus, treatment includes dorsiflexion osteotomy of either the first metatarsal or cuneiform [1].
  • For rigid medial and lateral cavus, treatment includes dorsiflexion osteotomies of the cuboid and cuneiforms [1].
  • For rigid hindfoot varus, treatment includes closing/sliding calcaneal osteotomy [1].
  • For clawing of the hallux, treatment includes adding an EHL transfer to the first metatarsal (Jones) [1].
  • Triple arthrodesis is rarely needed for severe cavus foot and should be avoided whenever possible [1].

Anatomy & Pathophysiology

Definition and Structural Components

  • A pes cavus (cavus foot) is defined by an elevated medial longitudinal arch secondary to forefoot plantar flexion or, less frequently, excessive calcaneal dorsiflexion [1].
  • The primary structural problem in cavus foot is forefoot plantar flexion, with the first ray often more markedly plantarflexed, resulting in forefoot pronation [1].
  • A cavovarus foot represents a multisegmental deformity characterized by a plantarflexed first ray, elevated medial longitudinal arch, and hindfoot varus [5].
  • Approximately 10% of skeletally mature individuals have cavovarus foot alignment, with most being asymptomatic [10].

Neuromuscular Etiology and Prevalence

  • Two-thirds of patients with a cavus foot have an underlying neurologic disorder, most commonly Charcot-Marie-Tooth (CMT) disease [1].
  • CMT disease is the most common neuromuscular cause of cavovarus foot deformity in children [9].
  • Cavovarus foot deformities are the most common orthopaedic deformities in all types of CMT disease except type II, in which planovalgus foot deformities are most common [9].
  • In a study of more than 2700 patients with CMT, 71% had foot deformities, with pes cavus and hammer toes being the most common [9].
  • Patients with bilateral cavovarus feet have a 78% probability of being diagnosed with CMT, which increases to 91% with a family history of CMT [3].
  • Cavus foot is rarely found in the absence of an underlying neuromuscular condition [2].
  • Cavus foot is rarely found in early childhood but is fairly frequent after 8–10 years of age [2].
  • Nonneurologic causes of cavovarus foot include congenital clubfoot, posttraumatic varus malunion, missed compartment syndrome, burn contractures, and idiopathic etiology [10].

Pathogenesis and Muscle Imbalance

  • The cause of cavus foot is usually muscle imbalance in a growing foot [2].
  • First ray plantar flexion may result from a weak tibialis anterior relative to the peroneus longus, but is more commonly caused by intrinsic weakness and contracture [1].
  • Neuropathic cavovarus deformity in CMT is caused by a combination of intrinsic and extrinsic weakness, beginning with weakness of intrinsic foot muscles and the anterior tibial muscle, with normal strength of the posterior tibial and peroneus longus muscles [9].
  • The triceps surae is weak and may be contracted in CMT-related cavovarus deformity [9].
  • The forefoot is pulled into equinus relative to the hindfoot, and the first ray becomes plantarflexed [9].
  • Long toe extensors attempt to assist the weak anterior tibial tendon in dorsiflexion but contribute to metatarsal plantarflexion, pronating the forefoot into a valgus position with mild adduction of the metatarsals [9].
  • Initially, the forefoot is supple and weightbearing, but as it becomes more rigidly pronated, the hindfoot assumes a varus position [9].
  • Weightbearing becomes a "tripod" mechanism, with weight borne on the heel and the first and fifth metatarsal heads [9].
  • Neuromuscular imbalance between a nonfunctioning peroneus brevis muscle and its antagonist, the posterior tibialis muscle, pulls the hindfoot into varus [10].
  • Forefoot-driven varus occurs when a relatively weak anterior tibialis muscle is overpowered by its antagonist, the peroneus longus muscle, plantarflexing the first ray [10].
  • Atrophy and contracture of the intrinsic musculature of the foot occur because of denervation, leading to collagen replacement of the intrinsic muscles [3].
  • These pathologic changes produce elevation of the longitudinal arch because of contracture of the plantar fascia [3].
  • Over time, the plantar fascia contracts, and the hindfoot varus deformity becomes more rigid [1].
  • Toe deformity results from nonfunctional intrinsic muscles, which normally flex the MTP joints and extend the distal and proximal interphalangeal (IP) joints [3].
  • With absent intrinsic function, long toe flexors create flexion deformities of the IP joints, and toes hyperextend through the MTP joints, assuming a dorsally displaced position with metatarsal head prominence [3].
  • Loss of intrinsic function, as seen in hereditary motor sensory neuropathy or diabetic neuropathy, predictably leads to claw toes [24].

Clinical Manifestations

  • Patients may report instability, such as ankle sprains [1].
  • One of the most common symptoms of cavus foot is anterior ankle pain, sometimes associated with toe walking [2].
  • Anterior ankle pain occurs because the forefoot is severely plantar flexed on the hindfoot, requiring marked ankle dorsiflexion to compensate [2].
  • When the cavus becomes too severe, ankle dorsiflexion is blocked, leading to anterior ankle impingement and pain [2].
  • The inability to dorsiflex further compromises forefoot clearance, and eventually, only the metatarsals can contact the floor [2].
  • This condition can be misinterpreted as ankle plantarflexion contracture, leading to unnecessary heel cord release [2].
  • Calluses beneath the metatarsal heads and heel skin are common [2].
  • Plantar callosities under the first and fifth metatarsal heads are common, as is plantar intrinsic wasting [5].
  • The medial longitudinal arch is elevated when viewed from the side, and the heel is inverted on standing when viewed from behind [5].
  • A "peek-a-boo" heel, where the medial heel pad is visible from behind, can signify hindfoot varus [5].
  • When standing, the foot has a bean-shaped appearance because of combined hindfoot varus and forefoot adductus [10].
  • Clawing of the hallux and lesser toes are often seen in neuromuscular cavovarus foot [10].
  • In CMT, increased pressure on the metatarsal heads leads to painful callosities along the lateral border of the foot and beneath the metatarsal heads [3].
  • Foot and ankle weakness caused the greatest impact on quality of life in a study of adults with CMT [3].

Radiographic Findings

  • Weight-bearing radiographs are required for evaluation [1].
  • Increased Meary angle is defined as the long axis of the talus intersecting the long axis of the first metatarsal dorsally on the lateral view, with a normal value of 0° to 5° [1].
  • In patients with CMT, Meary angle values average 18 degrees [3].
  • Increased calcaneal pitch is defined as the intersection of a line running along the undersurface of the calcaneus and the floor, with a pitch greater than 30° indicating a calcaneocavus foot [1].
  • On lateral radiographs, the fibula is often located posterior to the posterior border of the distal tibia at the level of the ankle [10].
  • The calcaneal pitch angle may be greater than 20° in cavovarus foot [10].
  • The talar first metatarsal angle may be apex dorsally angulated because of plantar flexion of the first ray [10].
  • On AP radiographs, the metatarsals are often adducted and the forefoot is rotated into supination [10].
  • On AP radiographs of the ankle, the talus may tilt into varus as a result of lateral ankle ligament insufficiency [10].
  • Varus is seen as parallelism of the talus and calcaneus on the lateral radiograph in CMT patients [3].
  • The lack of hindfoot equinus can be documented by measurement of the calcaneal pitch, which usually reveals dorsiflexion of the calcaneus and forefoot equinus with the apex of the deformity in the midfoot [3].
  • Hindfoot varus can be assessed using the AP-talocalcaneal angle, and midfoot cavus by the lateral talar–first metatarsal angle [5].
  • Foot supination can be quantified by metatarsal overlap [5].

Flexibility Assessment

  • If lateral foot elevation and first ray plantar flexion succeed in everting the hindfoot, the hindfoot deformity is driven by the plantarflexed first ray (forefoot-driven hindfoot varus) [5].
  • If the hindfoot varus corrects with the Coleman block test, the deformity is considered forefoot-driven varus or flexible varus [10].
  • If the hindfoot deformity does not correct with passive manipulation or the Coleman block test, the deformity is considered hindfoot-driven varus or fixed varus [10].
  • Fixed varus indicates that the Chopart joints are locked in varus and that a hindfoot corrective osteotomy is required [10].
  • With time, the varus deformity becomes fixed and does not correct when the block test is performed [3].
  • The Coleman block lateral radiograph is a mediolateral weight-bearing view used to evaluate hindfoot flexibility, rotational correction in the ankle, and degree of correction of forefoot supination [3].
  • Multiple clinical methods have been described to assess hindfoot flexibility, including the Coleman block test, oblique block test, and prone Price and Mubarak tests [5].

Clinical Presentation

Definition and Etiology

  • A pes cavus (cavus foot) is characterized by an elevated medial longitudinal arch secondary to forefoot plantar flexion or, less frequently, excessive calcaneal dorsiflexion [1].
  • Approximately two-thirds of patients with a cavus foot have an underlying neurologic disorder, most commonly Charcot-Marie-Tooth disease [1].
  • Cavus foot is frequently accompanied by hindfoot varus deformity (cavovarus foot) [2].
  • Cavus foot is a marker for neuromuscular disease, requiring a thorough search for the underlying cause [2].
  • In patients with bilateral cavovarus feet, there is a 78% probability of being diagnosed with Charcot-Marie-Tooth disease [3].
  • A family history of Charcot-Marie-Tooth disease increases the probability of diagnosis in patients with bilateral cavovarus feet to 91% [3].

Physical Examination Findings

  • Anterior ankle pain in cavus foot occurs because the severely plantar flexed forefoot requires marked ankle dorsiflexion to compensate, leading to impingement when dorsiflexion is blocked [2].
  • Calluses beneath the metatarsal heads and heel skin are common in cavus foot [2].
  • Plantar callosities under the first and fifth metatarsal heads are common clinical findings [5].
  • Plantar intrinsic wasting is a common finding on physical examination [5].
  • The medial longitudinal arch is elevated when viewed from the side [5].
  • The heel is inverted on standing when viewed from behind [5].
  • A "peek-a-boo" heel, where the medial heel pad is visible from behind, signifies hindfoot varus [5].
  • Clawing of the hallux and lesser toes is often seen in neuromuscular cavovarus foot [10].
  • The foot may have a bean-shaped appearance due to combined hindfoot varus and forefoot adductus [10].
  • Gait evaluation should look for subtle footdrop, compensatory toe clawing, ankle instability, and peroneal weakness [10].
  • Unilateral involvement suggests a focal diagnosis such as spinal cord anomaly or nerve injury [1].
  • Bilateral involvement with a positive family history is common with Charcot-Marie-Tooth disease, though asymmetry may be seen [1].

Diagnostic Testing

  • A neurologic examination and family history are essential for evaluation [1].
  • Electromyography and nerve conduction velocity studies are required for careful examination of the peripheral and central nervous systems [9].
  • Weight-bearing radiographs are required for radiographic assessment [1].
  • An increased Meary angle, where the long axis of the talus intersects the long axis of the first metatarsal dorsally, is a radiographic finding; normal value is 0° to 5° [1].
  • In patients with Charcot-Marie-Tooth disease, the Meary angle averages 18 degrees [3].
  • Increased calcaneal pitch, defined as the intersection of a line along the undersurface of the calcaneus and the floor, indicates a calcaneocavus foot if greater than 30° [1].
  • The Coleman block test assesses hindfoot flexibility by placing a 1-inch block under the lateral border of the foot [1].
  • If the hindfoot varus corrects with the Coleman block test, the deformity is considered forefoot-driven or flexible varus [10].
  • If the hindfoot deformity does not correct with passive manipulation or the Coleman block test, it is considered hindfoot-driven or fixed varus [10].
  • Fixed varus indicates that the Chopart joints are locked in varus and requires a hindfoot corrective osteotomy [10].
  • On AP radiographs, metatarsals are often adducted and the forefoot is rotated into supination [10].
  • The talus may tilt into varus on AP ankle radiographs as a result of lateral ankle ligament insufficiency [10].

Investigations

Clinical Evaluation

  • A neurologic examination and family history are essential for the evaluation of cavus foot [1].
  • Unilateral involvement of cavus foot suggests a focal diagnosis, such as a spinal cord anomaly or nerve injury [1].
  • Asymmetry may be seen in patients with Charcot-Marie-Tooth disease despite bilateral involvement [1].
  • Cavus foot is frequently accompanied by hindfoot varus deformity, clawing of the toes, and demonstrable weakness of ankle or foot muscles [2].
  • Calluses beneath the metatarsal heads and heel skin are common clinical findings in cavus foot [2].
  • Anterior ankle pain is one of the most common symptoms of cavus foot, sometimes associated with toe walking [2].
  • The inability to dorsiflex the ankle in severe cavus foot can be misinterpreted as an ankle plantarflexion contracture [2].

Physical Examination

  • Hindfoot flexibility is assessed by placing a 1-inch block under the lateral border of the foot, known as the Coleman block test [1].
  • Hindfoot varus in individuals with a cavovarus deformity is considered nonstructural if it can be corrected with the block test [2].

Imaging

  • MRI of the spine is indicated for patients with unilateral cavus foot involvement [1].
  • Diagnosis of cavus foot may require spinal MRI and electromyographic (EMG) studies to search for the underlying neuromuscular cause [2].
  • A standard series of weight-bearing radiographs of the foot includes AP, lateral, and oblique views [30].
  • The hindfoot alignment view or Saltzman view is commonly obtained to evaluate the axial alignment of the hindfoot in relation to the ankle above [30].
  • MRI can be useful in the diagnosis of metatarsalgia, such as distinguishing among a neuroma, cyst, bursa, or synovitis [14].
  • MRI is a fundamental tool in the workup of a patient with a soft-tissue or bone tumor in the foot [35].
  • MRI is a valuable imaging modality in the evaluation of patients with suspected bone or soft-tissue infection [35].
  • MRI has a high false-positive rate in the diagnosis of osteomyelitis, particularly with concurrent Charcot arthropathy [33, 34].
  • Labeled WBC scan or dual-image technetium/indium (Tc/In) scan is more sensitive and specific for osteomyelitis than isolated Tc scan [33, 34].
  • Normal MRI marrow signal confidently excludes osteomyelitis [35].

Treatment

Non-Operative

  • Conservative treatment of cavus foot includes accommodation by shoe modifications or inserts [2].
  • Shoe modifications and inserts do not actually correct the condition [2].
  • Initial management includes an orthotic that recesses the first ray and elevates the entire lateral foot, reserved for deformities with flexible hindfoot varus [5].
  • For mild, flexible, and painless cavus foot, treatment consists of Achilles tendon stretching and an eversion/dorsiflexion strengthening program [1].
  • Nonoperative treatment of the cavovarus foot, including the use of serial casting and botulinum toxin, has generally been unsuccessful [9].
  • A randomized trial found that 8 weeks of botulinum toxin to prevent pes cavus progression was safe and well tolerated but did not affect the progression of the deformity [9].
  • Medical treatment with high-dose ascorbic acid has been found to be ineffective in altering the natural history of Charcot-Marie-Tooth disease [9].

Operative

  • Joint-sparing procedures are preferred whenever possible for cavus foot [1].
  • A key to surgical decision making for cavus foot is the flexibility of the hindfoot [1].
  • For mild, progressive or symptomatic cavus foot, treatment is plantar release with or without peroneus longus to brevis transfer [1].
  • For varus caused by peroneal weakness, tibialis anterior and/or posterior tendon transfer to the peroneal muscles is indicated [1].
  • For moderate rigid medial cavus, treatment is dorsiflexion osteotomy of either the first metatarsal or cuneiform [1].
  • For rigid medial and lateral cavus, treatment is dorsiflexion osteotomies of the cuboid and cuneiforms [1].
  • For rigid hindfoot varus, treatment is a closing/sliding calcaneal osteotomy [1].
  • For clawing of the hallux, an EHL transfer to the first metatarsal (Jones) is added [1].
  • If the patient is symptomatic, the treatment of choice is plantar release with first metatarsal osteotomy and possible tendon transfers [2].
  • Severe deformity requires surgical correction by tendon transfers to restore muscle balance, midfoot wedge osteotomy to correct bony deformity, or triple arthrodesis [2].
  • When done early in the disease in young patients, soft tissue surgery consisting of plantar fascia release or extensive plantar release, including capsulotomies with tendon transfer, may be sufficient to postpone or avoid triple arthrodesis [3].
  • Surgical correction of the cavovarus foot in patients with CMT can be divided into deformity correction and rebalancing of deforming muscle forces [3].
  • For a plantarflexed first metatarsal with mild cavovarus and a fully flexible hindfoot, treatment involves soft-tissue procedures and possible first metatarsal osteotomy [9].
  • For increased plantarflexion of the first metatarsal, increased supination, and a stiffer hindfoot, treatment involves first metatarsal osteotomy, midfoot/hindfoot osteotomies, and possible triple arthrodesis [9].
  • For rigid cavovarus deformity, treatment is triple arthrodesis [9].
  • Surgical procedures for CMT foot deformities are classified as soft tissue for flexible deformities, osteotomy for stiffer flexible or rigid deformities, and joint stabilizing for completely rigid deformities [9].
  • Early, aggressive treatment when the hindfoot is flexible and early soft-tissue releases can delay the need for triple arthrodesis [9].
  • In equinocavovarus deformity, if the hindfoot is correctable into valgus, isolated soft-tissue surgeries can be used to correct the deformity [50].
  • A split transfer of the tibialis anterior tendon to the lateral cuneiform can maintain active dorsiflexion while reorienting the force vector out of varus [50].
  • If the tibialis anterior tendon is weak, a split tibialis posterior tendon transfer to the peroneus brevis should be used [50].
  • If the hindfoot is not correctable into valgus, tendon transfer should be coupled with a calcaneal lateral closing wedge osteotomy or a slide osteotomy [50].
  • Cavus can be addressed with a plantar fascia release through either a plantar or a medial incision [50].
  • If both cavus and equinus are present, their correction should be staged because the surgeon cannot control the contributions of each procedure if done concurrently [50].
  • When deformities are too severe to correct through reconstruction, or when reconstruction fails, triple arthrodesis is an option [50].
  • The addition of a lateral column lengthening to the triple arthrodesis has been described to address severe deformity [50].
  • Lateral column lengthening added to triple arthrodesis results in a stiff foot that is at higher risk for skin breakdown [50].
  • Reconstruction is preferred over triple arthrodesis when possible [50].
  • Several different osteotomies of the midfoot have been proposed for surgical reconstruction of a cavus foot, all involving removing a dorsally based V-shaped wedge of bone from the midfoot at or just proximal to the apex of the cavus deformity [41].
  • Plantar soft tissue release is generally performed either before or in addition to an osteotomy of the midfoot [41].
  • Cole described a dorsal closing wedge osteotomy of the midfoot with the proximal cut made through the navicular and cuboid bones [41].
  • Jahss proposed a tarsometatarsal dorsal wedge resection osteotomy for the correction of cavus deformity [41].
  • The amount of forefoot equinus that can be corrected with the Jahss osteotomy should not exceed 20 to 25 degrees [41].
  • Jahss recommended triple arthrodesis for feet with severe deformities because greater correction with the Jahss osteotomy led to the development of a rocker deformity in the sole of the foot and persistent symptoms [41].
  • If a callus is present on the sole of the foot preoperatively, the osteotomy must be performed proximal to the callus for successful redistribution of pressure across the foot [41].
  • Japas described a V-shaped osteotomy made dorsally with the apex at the navicular and limbs extending distally to just proximal to the cuboid–fifth metatarsal joint laterally and proximal to the medial cuneiform–first metatarsal joint medially [41].
  • The Japas osteotomy does not include resection of a wedge, so the foot is not shortened further by bony resection, yet the joints are all left mobile in the midfoot and hindfoot [41].
  • The Japas osteotomy cannot correct severe cavus because a wedge is not resected [41].
  • The Japas osteotomy cannot correct rigid hindfoot varus [41].
  • Wilcox and Weiner modified the Japas osteotomy by making a dome osteotomy with bone resection through the base of the fifth metatarsal, the cuboid, and the three cuneiforms [41].
  • At long-term follow-up of 139 feet, 76% of patients had satisfactory results with the Wilcox and Weiner modified Japas osteotomy [41].
  • Satisfactory results with the Wilcox and Weiner modified Japas osteotomy were only obtained in 67% of children younger than 8 years old [41].
  • Wicart and Serings performed plantar-based opening wedge osteotomies of the cuneiforms combined with plantar release and a calcaneal osteotomy, with satisfactory results in 64% of 36 feet [41].
  • Triple arthrodesis was ultimately necessary in 33% of patients treated with plantar-based opening wedge osteotomies of the cuneiforms combined with plantar release and a calcaneal osteotomy [41].
  • Correction of severe pes cavovarus or calcaneocavus has been achieved by osteotomy and gradual distraction and correction with external fixation such as the Ilizarov device [41].
  • The bone correction attained with Ilizarov reconstruction is insufficient for long-term satisfactory outcomes in cavus deformity [41].
  • Soft tissue balancing procedures or arthrodesis must be performed after Ilizarov reconstruction to decrease the likelihood of recurrence [41].
  • Arthrodesis should be avoided in patients with myelomeningocele as insensate feet are susceptible to skin breakdown and ulceration [45].

Complications

Post-traumatic Deformity

  • Pes cavus deformity is a reported adverse outcome following tarsal navicular fractures [51].
  • Coulibaly et al. reported an incidence of 26% of pes cavus deformities after navicular fracture care [51].

Neuromuscular Sequelae

  • In Charcot-Marie-Tooth disease, denervation leads to atrophy and contracture of the intrinsic musculature of the foot [3].
  • Collagen replacement of the intrinsic muscles of the foot occurs due to denervation in Charcot-Marie-Tooth disease [3].
  • Contracture of the plantar fascia in Charcot-Marie-Tooth disease increases pressure on the metatarsal heads [3].
  • Increased pressure on the metatarsal heads leads to painful callosities along the lateral border of the foot and beneath the metatarsal heads in Charcot-Marie-Tooth disease [3].
  • Absent intrinsic muscle function in Charcot-Marie-Tooth disease results in flexion deformities of the interphalangeal joints of the toes [3].
  • Toes in Charcot-Marie-Tooth disease hyperextend through the metatarsophalangeal joints, assuming a dorsally displaced position with metatarsal head prominence on the plantar aspect of the foot [3].
  • Foot and ankle weakness caused the greatest impact on quality of life in a study of adults with Charcot-Marie-Tooth disease [3].

Surgical Complications and Risks

  • Unnecessary heel cord release may be performed if anterior ankle impingement in cavus foot is misinterpreted as an ankle plantarflexion contracture [2].
  • Achilles tendon lengthening performed concomitantly with plantar fasciotomy is contraindicated because an intact Achilles tendon provides the resistance necessary to stretch contracted plantar tissues and correct the cavus deformity [1].

Recovery

  • Dynamic pedobarography has shown that operative treatment of cavovarus foot deformity does not normalize pressure distribution even when the foot deformity is corrected [3].
  • Undercorrection is the leading cause of poor outcomes in patients who undergo cavovarus reconstruction [10].
  • Nonsurgical treatment for cavovarus deformity includes utilization of laterally posted custom orthotic inserts with the posting extended to the midfoot to simulate a Coleman block test [10].
  • Nonsurgical treatment for cavovarus deformity includes physical therapy to optimize peroneal muscle strength and function [10].
  • A custom ankle-foot orthosis (AFO) can be considered for more severe cavovarus deformities involving the hindfoot or ankle [10].
  • Initial management of cavovarus foot includes an orthotic that recesses the first ray and elevates the entire lateral foot, reserved for deformities with flexible hindfoot varus [5].
  • For mild, flexible, and painless cavus foot deformity, treatment consists of Achilles tendon stretching and an eversion/dorsiflexion strengthening program [1].
  • For mild, progressive or symptomatic cavus foot deformity, treatment consists of plantar release with or without peroneus longus to brevis transfer [1].
  • For cavus foot deformity with varus caused by peroneal weakness, treatment involves adding tibialis anterior and/or posterior tendon transfer to the peroneal muscles [1].
  • For moderate rigid medial cavus deformity, treatment consists of dorsiflexion osteotomy of either the first metatarsal or cuneiform [1].
  • For rigid medial and lateral cavus deformity, treatment consists of dorsiflexion osteotomies of the cuboid and cuneiforms [1].
  • For rigid hindfoot varus deformity, treatment consists of a closing/sliding calcaneal osteotomy [1].
  • For clawing of the hallux in cavus foot deformity, treatment involves adding an extensor hallucis longus (EHL) transfer to the first metatarsal (Jones procedure) [1].
  • Triple arthrodesis is rarely needed for severe cavus foot deformity and should be avoided whenever possible [1].
  • Arthrodesis should be reserved for salvage procedures or in combination with tendon transfers in patients with severe deformity in whom joint-sparing surgery would fail or has failed [10].
  • Achilles tendon lengthening should not be performed concomitantly with plantar fasciotomy for cavus foot correction [1].

References

[1] Aaos Comprehensive Orthopaedic Review 3. Pediatric Foot Conditions > Pes Cavus.

[2] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 10Pediatric Orthopedic Surgery > 4. Cavus Foot.

[3] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Iliopsoas Muscle Transfer for Lateral Stability of the Hip > Orthopaedic Manifestations and Surgical Treatment > Foot.

[5] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Pediatric Lower Extremity and Foot Disorders > Cavovarus Foot.

[9] Campbell S Operative Orthopaedics 4 Volume Set. DIFFERENTIATION OF MUSCLE DISEASE FROM NERVE DISEASE > CHARCOT-MARIE-TOOTH DISEASE (PERONEAL MUSCULAR ATROPHY) > CAVOVARUS FOOT DEFORMITY.

[10] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Foot and Ankle Reconstruction > Cavovarus Foot.

[14] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 8Foot and Ankle Surgery > METATARSALGIA.

[24] Miller S Review Of Orthopaedics. 2. Hindfoot and midfoot > 3. Forefoot.

[30] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Foot and Ankle Anatomy and Biomechanics > Imaging > Plain Radiographs.

[33] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > CLINICAL PROBLEMS > 3. Diabetic foot infections.

[34] Miller S Review Of Orthopaedics. CLINICAL PROBLEMS > 3. Diabetic foot infections.

[35] Campbell S Operative Orthopaedics 4 Volume Set. OTHER DISORDERS OF FOOT AND ANKLE.

[41] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Plate 15.3 Kramer/Barmada Osteotomy of the Base of the Femoral Neck for Slipped Capital Femoral Epiphysis > Midfoot Osteotomies..

[45] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Neuromuscular Disorders in Children > Myelomeningocele > Foot and Ankle Deformity.

[50] Orthopaedic Knowledge Update. Cerebral Palsy > Lower Extremity Surgery in Ambulatory Children > Foot and Ankle.

[51] Rockwood And Green S Fractures In Adults. 67: Fractures and Dislocations of the Midfoot and Forefoot > Management of Adverse Outcomes and Unexpected Complications Related to Tarsal Navicular Fractures.

Creative Commons BY-NC 4.0

CC Creative Commons licence
BY Attribution — you must credit the source
NC NonCommercial — not for commercial use

Attribution-NonCommercial 4.0 International


Creative Commons Corporation ("Creative Commons") is not a law firm and does not provide legal services or legal advice. Distribution of Creative Commons public licenses does not create a lawyer-client or other relationship. Creative Commons makes its licenses and related information available on an "as-is" basis. Creative Commons gives no warranties regarding its licenses, any material licensed under their terms and conditions, or any related information. Creative Commons disclaims all liability for damages resulting from their use to the fullest extent possible.

Using Creative Commons Public Licenses

Creative Commons public licenses provide a standard set of terms and conditions that creators and other rights holders may use to share original works of authorship and other material subject to copyright and certain other rights specified in the public license below. The following considerations are for informational purposes only, are not exhaustive, and do not form part of our licenses.

Considerations for licensors: Our public licenses are intended for use by those authorized to give the public permission to use material in ways otherwise restricted by copyright and certain other rights. Our licenses are irrevocable. Licensors should read and understand the terms and conditions of the license they choose before applying it. Licensors should also secure all rights necessary before applying our licenses so that the public can reuse the material as expected. Licensors should clearly mark any material not subject to the license. This includes other CC- licensed material, or material used under an exception or limitation to copyright. More considerations for licensors: wiki.creativecommons.org/Considerations_for_licensors

Considerations for the public: By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor's permission is not necessary for any reason--for example, because of any applicable exception or limitation to copyright--then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. More considerations for the public: wiki.creativecommons.org/Considerations_for_licensees


Creative Commons Attribution-NonCommercial 4.0 International Public License

By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NonCommercial 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.

Section 1 -- Definitions.

a. Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.

b. Adapter's License means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.

c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.


Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.