Skip to content

Patients › Foot

Deformidades dos dedos menores do pé

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

As deformidades dos dedos menores do pé alteram a posição e o movimento dos dedos. Um ou mais dos seus dedos menores podem curvar-se para baixo, ficar por cima ou por baixo de outro dedo, ou pressionar contra o sapato. A pele sobre o nódulo ósseo pode engrossar e endurecer; esse atrito pode deixar a área inflamada e dolorida. Em alguns casos, a pele se rompe, formando uma úlcera.

A dor geralmente é sentida na parte anterior do pé ou no topo do dedo curvado. Ela tende a piorar quando os dedos são comprimidos em sapatos apertados ou estreitos, pois o sapato pressiona o osso e fricciona os tecidos moles ao redor. Calçados mais largos aliviam essa pressão e, muitas vezes, diminuem o desconforto. Esse tipo de dor no pé e no tornozelo reduz a mobilidade e pode afetar negativamente tanto o humor quanto o corpo.

Atividades diárias que exigem carga na parte dianteira do pé tornam-se mais difíceis. Caminhar até o mercado, ficar em pé enquanto cozinha, subir escadas ou trabalhar o dia todo em pé podem intensificar a dor. Você pode acabar mudando a maneira como anda para evitar pressionar os dedos doloridos.

Algumas pessoas com esses problemas nos dedos também apresentam alterações mais acima no pé, como arco plantar muito elevado ou calcanhar desalinhado. Se esse for o seu caso, isso pode influenciar a forma como todo o pé suporta o peso do corpo.

Se você tem artrite reumatoide, a parte dianteira do pé também pode ser afetada: os dedos podem perder a forma normal, juntamente com alterações no dedão do pé.

O que está realmente acontecendo

Os dedos dos pés são mantidos retos graças ao equilíbrio entre dois grupos musculares. Um grupo corre ao longo da parte superior do pé e puxa os dedos para cima; o outro corre pela sola e os puxa para baixo. Quando esse equilíbrio se rompe, as articulações de um dedo deixam de funcionar em conjunto: o dedo se dobra para baixo numa articulação enquanto se dobra para cima em outra, gerando as formas curvadas que se podem ver e sentir.

O problema geralmente começa com uma pequena almofada de tecido na parte inferior do dedo, onde ele se conecta à parte anterior do pé. Pense nela como uma espécie de vedante que estabiliza a articulação. Quando esse “vedante” se desgasta ou se rompe, o dedo perde sua fixação. O tendão da parte superior então “vence” a disputa, fazendo com que a base do dedo se eleve e as articulações médias se dobrem para baixo. À medida que o dedo se curva, a extremidade do osso longo do pé é pressionada contra a sola. A almofada de gordura que normalmente amortece essa região é deslocada para a frente, deixando você apoiado sobre o osso, com menos amortecimento. É por isso que a parte anterior do pé fica dolorida, e por que podem surgir calos e úlceras nessa área.

Os sapatos também têm papel importante. Calçados apertados ou estreitos comprimem os dedos e intensificam o atrito que inflama a pele sobre a saliência. Algumas pessoas nascem com uma conformação do pé que favorece esse problema; condições que afetam os nervos ou músculos também podem desencadeá-lo. Por exemplo, um arco alto resulta de um desequilíbrio muscular num pé em desenvolvimento, alterando a forma como todo o pé suporta o peso do corpo.

Se o dedão do pé também estiver se desviando para o lado, o mecanismo é o mesmo: os tecidos que o mantêm reto vão cedendo gradualmente, o dedão gira e se desloca em direção aos dedos menores, que por sua vez podem se dobrar devido à falta de espaço.

O que podemos fazer a respeito

As radiografias com carga são o ponto de partida habitual; são feitas enquanto você está em pé, podendo incluir imagens detalhadas dos dedos. A ressonância magnética pode ser utilizada quando precisamos de uma visão mais clara dos tecidos moles ao redor da articulação.

Na maioria dos casos de deformidades nos dedos, iniciamos com tratamento não cirúrgico. O principal método é a mudança de calçados: sapatos com biqueira alta e espaçosa ajudam a aliviar a pressão sobre o dedo deformado. Mangas de espuma ou de gel de silicone para os dedos, além de almofadas de crista, podem amortecer as áreas doloridas. O uso de acolchoamento sob a parte anterior do pé, incluindo palmilhas metatarsais, ajuda a distribuir a carga para longe da região dolorida. No caso de “bunionette” – a saliência na parte externa do dedo mínimo –, podemos também desbastar o calo endurecido. Se você também tem pé plano, uma palmilha ou órtese personalizada pode ser útil. Embora a fisioterapia e essas medidas simples não consigam endireitar o dedo propriamente dito, elas podem aliviar os sintomas. Geralmente pedimos que você as teste por algum tempo antes de considerar a cirurgia.

As injeções de esteroides, às vezes chamadas de cortisona, têm um papel muito limitado nesses casos. Especialmente no caso do dedo em garra, elas podem enfraquecer os ligamentos que mantêm o dedo estável, podendo piorar a deformidade. Por isso, as utilizamos com muita cautela, ou até mesmo evitamos.

A cirurgia é indicada quando o tratamento não cirúrgico não trouxe alívio suficiente, ou quando o dedo já se tornou rígido numa posição fixa. A operação é adaptada ao seu dedo e às articulações afetadas. Pode envolver o endireitamento do dedo mediante a liberação de tecidos moles tensos, a remoção de um pequeno fragmento ósseo de uma articulação curvada, ou o encurtamento de um osso longo do pé para reequilibrar a parte anterior do pé. Os tendões podem ser redirecionados ou alongados para restaurar o equilíbrio da tração que mantém o dedo reto. A almofada danificada na base do dedo também pode ser reparada. Quando uma articulação está muito desgastada, pode ser realizada uma artrodese para manter o dedo reto e estável. Geralmente usamos fixação temporária com fios para manter tudo no lugar durante a cicatrização; em alguns casos, implantes permanentes mais recentes são uma alternativa. Conversaremos sobre qual abordagem se adequa ao seu pé, e decidiremos juntos.

O que esperar

Com sapatos mais espaçosos, acolchoamento e outras medidas simples, a dor na parte anterior do pé e sobre o dedo encurvado muitas vezes diminui. Contudo, essas medidas não conseguem endireitar um dedo que já tenha mudado de forma. Se o dedo ficou rígido numa posição fixa, normalmente permanecerá assim sem cirurgia.

Caso a cirurgia seja a melhor opção para você, o objetivo é obter um dedo mais reto e confortável, além de uma distribuição mais uniforme do peso no antepé. A recuperação é gradual; será preciso tempo para que o dedo cicatrize e volte a se comportar como parte do pé. Alguns procedimentos permitem movimentar o dedo logo no início, reduzindo o risco de rigidez; outros envolvem uma área maior do pé e demandam mais tempo para a recuperação.

Toda cirurgia traz alguns riscos. Um risco raro, porém imediato após a cirurgia nos dedos, é a redução do fluxo sanguíneo para o dedo. Isso ocorre com mais frequência em fumantes ou em pacientes que estão corrigindo um dedo pela segunda vez. O cirurgião explicará quais riscos são relevantes para o seu caso específico.

O prognóstico depende do seu pé e do procedimento escolhido. Alguns métodos apresentam baixo índice de complicações; já outros, especialmente aqueles que combinam várias etapas na correção dos dedos menores, tendem a gerar mais complicações, resultados menos favoráveis e recuperação mais lenta em comparação com versões mais simples da mesma cirurgia. O cirurgião avaliará qual abordagem oferece ao seu dedo as melhores chances de bom resultado e recuperação tranquila.

Quando procurar ajuda médica

Consulte seu médico de família se uma área dolorida sobre um dedo do pé encurvado ou na parte da frente do pé não melhorar após algumas semanas usando sapatos mais largos, ou se a pele espessa nessa região se transformar em uma úlcera. Solicite avaliação por um especialista se a dor impedir que você caminhe, trabalhe ou durma, ou se os dedos do pé estiverem tão encurvados que não ficam mais planos dentro do sapato. Mencione também qualquer alteração na forma do seu pé mais acima, como um arco muito elevado ou um calcanhar desalinhado, pois isso pode afetar todo o pé e talvez também precise de atenção.


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.

Anatomy & Pathophysiology

Musculotendinous Anatomy

  • The extensor digitorum longus muscle originates from the tibia and fibula and inserts into the middle and distal phalanges of the lesser toes [2].
  • The flexor digitorum longus muscle originates from the tibia and inserts into the distal lesser phalanges [2].
  • The extensor digitorum longus is innervated by the deep peroneal nerve [2].
  • The flexor digitorum longus is innervated by the tibial nerve [2].
  • The extensor digitorum longus acts to dorsiflex the toes [2].
  • The flexor digitorum longus acts to plantar flex the lesser toes [2].
  • The extensor digitorum brevis is the only dorsal intrinsic muscle of the foot [15].
  • The extensor digitorum brevis is innervated by the lateral terminal branch of the deep peroneal nerve [15].
  • Lumbrical muscles are located plantar to the transverse metatarsal ligament [15].
  • Interosseous tendons are located dorsal to the transverse metatarsal ligament [15].

Neurovascular Anatomy

  • The dorsalis pedis artery is a continuation of the anterior tibial artery that passes deep under the inferior extensor retinaculum [9].
  • As the dorsalis pedis artery passes anterior to the ankle joint, it lies between the tendons of the extensor hallucis longus medially and the extensor digitorum longus laterally [9].
  • The deep peroneal nerve lies immediately lateral to the dorsalis pedis artery [9].
  • The arcuate artery arises from the dorsalis pedis artery in the region of the bases of the metatarsals and passes laterally [9].
  • The second, third, and fourth dorsal metatarsal arteries arise from the arcuate artery and descend to the dorsal surfaces of the respective dorsal interosseous muscles [9].
  • The first dorsal metatarsal artery is the continuation of the dorsalis pedis artery [9].
  • The first dorsal metatarsal artery runs distally, usually on the dorsal surface of the first dorsal interosseous muscle [9].
  • The first dorsal metatarsal artery supplies branches to the dorsal skin, the first and second metatarsals, and the interosseous muscles [9].
  • Near the first web space between the first and second toes, the first dorsal metatarsal artery divides into at least two branches [9].
  • One branch of the first dorsal metatarsal artery passes deep to the tendon of the extensor hallucis longus to supply the medial side of the great toe [9].
  • The other branch of the first dorsal metatarsal artery divides to supply the adjacent sides of the great and second toes [9].
  • The deep plantar, or communicating, artery leaves the dorsalis pedis at the base of the first metatarsal [9].
  • The deep plantar artery passes toward the plantar surface of the foot between the heads of the first dorsal interosseous muscle [9].
  • The deep plantar artery communicates with the lateral plantar artery to complete the plantar arterial arch [9].
  • The deep plantar artery supplies a branch to the medial side of the great toe [9].
  • The first plantar metatarsal artery is the continuation of the deep plantar artery [9].
  • The first plantar metatarsal artery passes distally in the first interosseous space and divides to supply the adjacent sides of the great and second toes from the plantar side [9].
  • In 78% to 88% of feet, the first dorsal metatarsal artery lies superficial to or just within the substance of the first dorsal interosseous muscle [9].
  • In 12% to 22% of feet, the first dorsal metatarsal artery lies plantar to the first metatarsal [9].
  • The venous drainage from the dorsum of the toes and foot flows into the dorsal venous arches, feeding the greater and lesser saphenous systems [9].
  • Additional venous drainage from the dorsum of the foot occurs through the veins accompanying the dorsalis pedis artery [9].
  • The dorsal surfaces of the toes and foot receive sensory innervation through the superficial peroneal nerve branches [9].
  • The first web space is innervated by the deep peroneal nerve [9].
  • The plantar surface of the foot is innervated by the digital branches of the medial plantar nerve [9].

Pathophysiology of Lesser Toe Deformities

  • Deformities of the lesser toes result from an imbalance between the intrinsic and extrinsic musculotendinous units of the toes [5].
  • With hyperextension at the metatarsophalangeal (MTP) joint, the strong flexors overpower the intrinsic extensors of the interphalangeal (IP) joints [5].
  • The overpowering of intrinsic extensors by strong flexors results in flexion deformities at the IP joints and extension deformities at the MTP joints [5].
  • Lesser MTP deformity starts with dysfunction of the plantar plate [5].
  • Mallet toe is defined as a hyperflexion deformity at the distal interphalangeal (DIP) joint [5].
  • Hammer toe is defined as a flexion deformity at the proximal interphalangeal (PIP) joint and an extension deformity at the MTP and DIP joints [5].
  • Claw toe is defined as an extension deformity at the MTP joint combined with hyperflexion at the PIP and DIP joints [5].
  • The difference between a hammer toe and a claw toe is the positioning of the DIP joint [5].
  • As claw toe develops, flexor tendons pull the IP joints into flexion and the MTP joint into extension [5].
  • The pulling of the MTP joint into extension depresses the metatarsal head and pulls the plantar fat pad distally [5].
  • Depression of the metatarsal head and distal migration of the plantar fat pad result in metatarsalgia, callus, or ulcer formation [5].
  • The primary deficiency at the MTP joint level in claw toe is dysfunction or tearing of the plantar plate [5].
  • The plantar plate usually holds the base of the phalanx in alignment with the metatarsal head [5].
  • Bunionette deformity, or tailor’s bunion, is defined as a prominence of the lateral aspect of the fifth metatarsal head [5].
  • Bunionette deformity causes pain over the lateral or plantar aspect of the MTP joint, particularly with compressive shoewear [3].
  • Three distinct types of bunionette deformity are described based on the anatomic location of the deformity along the fifth metatarsal [3].
  • Type I bunionette deformity is distinguished by the presence of an enlarged fifth metatarsal head [3].
  • Type II bunionette deformity demonstrates lateral bowing of the fifth metatarsal diaphysis [3].
  • Type III bunionette deformity demonstrates an abnormally widened fourth–fifth metatarsal angle [3].
  • The normal fourth–fifth metatarsal angle is less than 8 degrees [3].
  • Bunionette deformity in conjunction with ipsilateral hallux valgus and metatarsus primus varus is termed splayfoot [3].
  • Cavus foot is a foot with an abnormally high arch [1].
  • Cavus foot frequently accompanies hindfoot varus deformity, known as cavovarus foot [1].
  • Cavovarus foot may be associated with clawing of the toes and demonstrable weakness of ankle or foot muscles [1].
  • Calluses beneath the metatarsal heads and heel skin are common in cavus foot [1].
  • The cause of cavus foot is usually muscle imbalance in a growing foot [1].
  • Cavus is rarely found in early childhood but is fairly frequent after 8–10 years of age [1].
  • Intrinsic muscle weakness is a major cause of cavus foot [1].
  • Weakness of the peroneal or anterior tibialis muscles is also implicated in the cause of cavus foot [1].
  • Cavus foot is rarely found in the absence of an underlying neuromuscular condition [1].
  • Cavus foot is a marker for neuromuscular disease [1].
  • In cavus foot, the forefoot is severely plantar flexed on the hindfoot, requiring marked ankle dorsiflexion to compensate [1].
  • When cavus becomes too severe, ankle dorsiflexion is blocked, leading to anterior ankle impingement and pain [1].
  • The inability to dorsiflex further compromises forefoot clearance, eventually allowing only the metatarsals to contact the floor [1].
  • This condition can be misinterpreted as ankle plantarflexion contracture, leading to unnecessary heel cord release [1].
  • Hallux valgus is defined as lateral deviation of the great toe with medial deviation of the first metatarsal [7].
  • The pathophysiology of hallux valgus is likely multifactorial [7].
  • Intrinsic factors contributing to hallux valgus include genetic predisposition, ligamentous laxity, and predisposing anatomy such as a convex metatarsal head or pes planus [7].
  • Extrinsic factors contributing to hallux valgus include certain types of shoewear, such as narrow toe boxes and high heels [7].
  • The pathoanatomy of hallux valgus involves medial capsular attenuation [7].
  • In hallux valgus, the proximal phalanx drifts laterally [7].
  • Lateral drift of the proximal phalanx leads to plantar-lateral migration of the abductor hallucis [7].
  • Plantar-lateral migration of the abductor hallucis causes the proximal phalangeal unit to plantar flex and pronate the hallux [7].
  • The pronation of the hallux is amplified by the proximal phalangeal attachment of the adductor hallucis [7].
  • Lateral deviation of the extensor hallucis longus and flexor hallucis longus causes a muscular imbalance and deforming force for valgus progression and pronation of the great toe [7].
  • In hallux valgus, the first metatarsal head moves medially off the sesamoids, increasing the intermetatarsal angle [7].
  • Pronation in hallux valgus leads to rounding of the lateral metatarsal head, which should have a flat contour with no rotational deformity [7].
  • Secondary contracture occurs in the lateral capsule, adductor hallucis, and lateral metatarsal-sesamoid and intermetatarsal ligaments in hallux valgus [7].
  • The pathoanatomy of hallux valgus involves gradual failure of the medial supportive structures, including the medial collateral ligament and tibial sesamoid, resulting in a varus position of the first metatarsal [28].
  • Valgus deviation at the MTP joint of the proximal phalanx subsequently develops as hallux valgus progresses [28].
  • As hallux valgus progresses, the alignment of the flexor and extensor hallucis longus tendons shifts laterally relative to the MTP joint, further exacerbating the deformity [28].
  • First metatarsal varus results in a prominent first metatarsal head medially, which is the bump or "bunion" reported by the patient [28].
  • Secondary pathology and deformity can develop in the lesser toes, such as hammertoes and claw toes, in patients with hallux valgus [28].
  • The etiology of hallux valgus is a combination of intrinsic factors such as genetic predisposition or a hypermobile first tarsometatarsal joint, and extrinsic factors predominantly related to high-heeled shoes with a narrow toe box [28].
  • Other predisposing factors for hallux valgus include rheumatoid or inflammatory arthritis, generalized ligamentous laxity, and dysmorphism of the first metatarsal [28].
  • Hallux valgus deformity is usually progressive, although the rate and degree of progression is often nonlinear [28].
  • Hallux valgus is most commonly seen in female patients in their fourth or fifth decades of life [28].
  • Adolescent bunion is frequently hereditary and usually seen in early adolescence [32].
  • Adolescent bunion is almost always found in conjunction with a wide forefoot caused by varus (medial deviation) of the first metatarsal shaft, known as metatarsus primus varus [32].
  • The wide forefoot in adolescent bunion allows severe lateral deviation of the great toe, causing the prominent base of the great toe to rub against the inside of the shoe and create a painful bunion [32].
  • Many adolescent bunions are progressive and require surgical management [32].
  • Surgery for adolescent bunion must address each aspect of the deformity, including trimming the bunion, correcting the varus angulation of the first metatarsal by osteotomy, and centralizing and balancing the hallux valgus by lengthening the adductor hallucis muscle [32].
  • There is a fairly high incidence of recurrence of adolescent bunion deformity following surgery [32].

Compartment Anatomy

  • Most authorities previously believed there were four compartments in the foot: medial, lateral, central, and interosseous [14].
  • The medial compartment lies on the plantar surface of the hallux [14].
  • The lateral compartment is on the plantar surface of the fifth metatarsal [14].
  • The central compartment lies on the plantar surface of the foot [14].
  • The interosseous compartment lies dorsal to the others between the metatarsals [14].
  • The medial compartment contains the intrinsic muscles of the great toe and flexor digiti minimi [14].
  • The lateral compartment contains the abductor digiti minimi [14].
  • The superficial central compartment contains the flexor digitorum brevis [14].
  • The deep (calcaneal) central compartment contains the quadratus plantae [14].
  • The adductor hallucis compartment contains the adductor hallucis [14].
  • The interosseous compartments contain the interosseous muscles and digital nerves [14].
  • Manoli and Weber challenged the concept of four compartments using cadaver infusion techniques, proposing nine compartments in the foot [14].
  • The nine-compartment model includes two central compartments: one superficial containing flexor digitorum brevis, and one deep (calcaneal) containing quadratus plantae [14].
  • The deep calcaneal compartment communicates with the deep posterior compartment of the leg [14].
  • Each of the four interosseous muscles and the adductor hallucis lies in separate compartments in the nine-compartment model [14].
  • The barrier between the superficial and calcaneal compartments becomes incompetent at a pressure of 10 mm Hg [14].
  • A pressure of 10 mm Hg is much lower than that required to produce an acute compartment syndrome [14].

Tarsal Tunnel Anatomy

  • The tarsal tunnel is a fibroosseous tunnel within the posteromedial ankle and hindfoot [6].
  • The tibial nerve, posterior tibial artery, accompanying veins, posterior tibial tendon, flexor digitorum longus, and flexor hallucis longus tendons pass into the foot through the tarsal tunnel [6].
  • The flexor retinaculum acts as the roof of the tarsal tunnel and extends from the medial malleolus to the medial side of the calcaneal tuberosity [6].
  • The medial distal tibia, talus, and calcaneus make up the floor of the tarsal tunnel [6].
  • Septa that separate the posterior tibial, flexor digitorum longus, and flexor hallucis longus tendons project from the fibrous roof to the calcaneus [6].
  • Between the flexor digitorum longus and flexor hallucis longus tendons, the tibial nerve, posterior tibial artery, and accompanying veins pass to enter the foot [6].
  • Before reaching the foot, the tibial nerve divides into three terminal branches: the medial calcaneal nerve, lateral plantar nerve, and medial plantar nerve [6].
  • Typically, the tibial nerve branches within the tunnel just proximal and deep to the upper edge of the abductor hallucis muscle [6].
  • The medial calcaneal nerve branches first, traveling posteriorly to the subcutaneous tissue [6].
  • The first branch of the lateral plantar nerve passes under the abductor, over the medial fascia of the quadrates plantae, deep to the plantar fascia, and under the heel to the flexor digitorum brevis [6].
  • The first branch of the lateral plantar nerve sends a sensory branch to the central heel skin and terminates in the abductor digiti quinti [6].
  • Anterior to its first branch, the lateral plantar nerve passes deep to the abductor fascia and plantar fascia and over the quadrates plantae [6].
  • The lateral plantar nerve continues distally under the flexor digitorum brevis, terminating in the fourth web space and supplying a branch to the third web space [6].
  • The lateral plantar nerve supplies motor branches to the intrinsic muscles [6].
  • The medial plantar nerve innervates the abductor and continues under the abductor and the plantar fascia to form the common digital nerves [6].
  • The common digital nerves terminate to the first, second, and third web spaces and provide motor branches to the interossei and lumbricals [6].
  • Historically, tarsal tunnel syndrome referred to tibial nerve entrapment beneath the flexor retinaculum [6].
  • Distal tarsal tunnel syndrome involves entrapment of the distal tibial nerve branches as they enter the foot [6].
  • Sources of constriction beneath and adjacent to the tarsal tunnel include bone fragments, tenosynovitis, ganglia, soft-tissue encroachment in inflammatory arthritis, varicosities, neural tumors, perineural fibrosis, tarsal coalition, and calcaneal osteotomies [6].
  • A fixed valg

Investigations

General Imaging Principles

  • Weight-bearing anteroposterior, lateral, and oblique views of the foot are included in the radiographic evaluation for metatarsalgia [30].
  • The skyline view of the metatarsal heads, obtained with the metatarsophalangeal joints in dorsiflexion, is helpful to evaluate overall alignment and demonstrate the height of the metatarsal heads [30].
  • Magnetic resonance imaging (MRI) can be useful in the diagnosis of metatarsalgia to distinguish among a neuroma, cyst, bursa, or synovitis [30].
  • MRI is a fundamental tool in the workup of a patient with a soft-tissue or bone tumor in the foot [34].
  • Focused MRI imaging of the metatarsophalangeal joints can detect sesamoid pathology and plantar plate injuries [34].
  • MRI is a valuable imaging modality in the evaluation of patients with suspected bone or soft-tissue infection, detecting osteomyelitis well before radiographic abnormalities are visible [34].
  • In neuropathic patients, the specificity of MR signal abnormalities for osteomyelitis is reduced [34].
  • Normal MRI marrow signal confidently excludes osteomyelitis in the foot [34].
  • The addition of contrast-enhanced MRI sequences is helpful in defining nonenhancing fluid collections, abscesses, and devascularized or gangrenous tissue [34].
  • Computed tomography (CT) scans are important in assessing fractures and for congenital bony coalitions [29].
  • Radio-isotope scanning is excellent for localizing areas of abnormal blood flow or bone remodelling activity, which suggest the presence of covert infection [29].
  • Magnetic resonance imaging (MRI) and ultrasound are used to demonstrate soft-tissue problems, such as tendon and ligament injuries, and can diagnose joint effusions and bone infections [29].
  • Stress X-rays complement clinical tests for ankle stability and can be carried out under general anaesthesia if stress manoeuvres are painful [29].

Specific Pathology Imaging

  • Ultrasonography has been reported to be 85% accurate in diagnosing interdigital neuroma [25].
  • MRI may be useful for diagnosing interdigital neuroma, and the administration of contrast medium may increase its accuracy [25].
  • Injection of the involved web space with local anesthetic that results in relief of neuritic symptoms is diagnostic of interdigital neuroma [25].
  • Injections performed under ultrasound guidance for interdigital neuroma have higher short-term relief compared with blind injections [25].
  • Weight-bearing radiographs are useful for excluding a stress fracture of the metatarsal neck in the evaluation of interdigital neuroma [25].
  • Interdigital or Morton neuroma is most frequently found in the distal third metatarsal interspace on MRI [34].
  • Unlike most other tumors, interdigital neuroma lacks increased signal on T2-weighted MRI sequences [34].
  • Plantar fibroma or plantar fibromatosis is usually confirmed by the presence of a signal-poor mass arising from the plantar fascia on MRI [34].

Neuromuscular and Deformity Workup

  • Diagnosis of cavus foot requires a thorough search for the underlying cause and may require neurologic consultation, spinal MRI, and electromyographic (EMG) studies [1].
  • A neurologic examination and a family history are essential in the evaluation of pes cavus [36].
  • MRI of the spine is indicated with unilateral involvement in pes cavus [36].
  • Hindfoot flexibility in pes cavus is assessed by placing a 1-inch block under the lateral border of the foot (Coleman block test) [36].
  • Weight-bearing radiographs are required for the evaluation of pes cavus [36].
  • An increased Meary angle, where the long axis of the talus intersects the long axis of the first metatarsal dorsally on the lateral view, is a radiographic finding in pes cavus [36].
  • The normal value for the Meary angle is 0° to 5° [36].
  • An increased calcaneal pitch, defined as the intersection of a line running along the undersurface of the calcaneus and the floor, is a radiographic finding in pes cavus [36].
  • A calcaneal pitch greater than 30° indicates a calcaneocavus foot [36].

Treatment

Non-Operative

  • Shoewear modification, strategic padding, and shaving of the symptomatic callus are usually effective for bunionette deformity [3].
  • With plantar callus or associated pes planus, a metatarsal pad or custom orthotic device should be considered for bunionette deformity [3].
  • Nonsurgical treatment for mallet toe includes wearing shoes with high toe boxes and using foam or silicone gel toe sleeves or crest pads [5].
  • Nonsurgical treatment for hammer toe includes wearing shoes with high toe boxes and using foam or silicone gel toe sleeves [5].
  • Initial nonsurgical treatment for claw toe is aimed at shoe-wear modification, with adequate plantar padding (including metatarsal pad inserts) and a shoe with a high toe box [5].
  • Crest pads may be used for the nonsurgical management of claw toe [5].
  • Steroid injections have very limited indications for claw toe and should be used judiciously [5].
  • Steroid injections for claw toe frequently result in weakening of the collateral ligaments and plantar plate resulting in progression and worsening of the deformity [5].

Operative: Bunionette

  • Lateral metatarsal head condylectomy is the surgical treatment for type I bunionette deformity [3].
  • Distal fifth metatarsal osteotomy (i.e., chevron) is the surgical treatment for type II bunionette deformity [3].
  • Oblique diaphyseal osteotomy is the surgical treatment for type III bunionette deformity [3].
  • Metatarsal head resection should be considered for salvage in bunionette deformity [3].
  • Proximal osteotomy should be avoided for bunionette deformity owing to the tenuous blood supply at the proximal metadiaphyseal junction of the fifth metatarsal [3].

Operative: Mallet Toe

  • A flexible mallet toe deformity can be corrected with a percutaneous release of the FDL tendon at its insertion into the base of the distal phalanx [5].
  • In fixed mallet toe deformity, surgical correction involves resection of the distal condyles of the middle phalanx and repair of the extensor tendon combined with temporary wire fixation [5].
  • Recurrent MTP joint instability after surgical correction of mallet toe is usually a result of persistent plantar plate dysfunction [5].

Operative: Hammer Toe

  • Surgery for hammer toe is indicated when nonsurgical treatment does not provide adequate relief of symptoms [5].
  • In the absence of MTP pathology, surgical correction of hammer toes involves resection of the distal condyles of the proximal phalanx of the toe [5].
  • Resection for hammer toe may be combined with an FDL tenotomy, performed either via the dorsal incision used for the condylar resection or through a plantar percutaneous release [5].
  • The toe should be pinned with temporary wire fixation during hammer toe correction [5].
  • Newer permanent implants are available to eliminate the need for K-wire fixation in hammer toe surgery [5].
  • Numerous studies have shown only minimal improvement in satisfaction without improvement in clinical outcomes, but at a significantly higher cost for the implants used in hammer toe surgery [5].
  • If the MTP joint is involved in hammer toe deformity, correction is the same as that for claw toe deformity [5].

Operative: Claw Toe

  • The MTP imbalance in claw toe is addressed with an extensor tendon Z-plasty lengthening and MTP capsular release [5].
  • Extensor tendon Z-plasty lengthening and MTP capsular release may be combined with a distal oblique metatarsal shortening osteotomy when associated with a long second metatarsal [5].
  • Extensor tendon Z-plasty lengthening and MTP capsular release may be combined with a FDL-to-EDL (Girdlestone-Taylor) tendon transfer to achieve balance of the affected MTP joint [5].
  • Newer procedures for claw toe include repairing the plantar plate at the proximal phalanx plantar insertion [5].
  • In plantar plate repair for claw toe, the plantar plate is captured with a nonabsorbable suture using a suture passer system [5].
  • In plantar plate repair for claw toe, the suture is passed through drill holes in the base of the proximal phalanx and tied dorsally with the toe positioned in slight plantar flexion [5].
  • When there is a crossover component to claw toe deformity, the damaged collateral ligament is repaired with nonabsorbable suture [5].
  • The hammer toe and mallet toe components of claw toe deformity are corrected via a proximal phalangeal distal condylar resection and FDL tenotomy [5].
  • A wire is placed across the DIP, PIP, and MTP joints for temporary stabilization during claw toe correction [5].
  • Persistent plantar plate dysfunction may result in recurrence of claw toe deformity [5].

Operative: Axial Plane Deformity

  • In the mildest cases of varus or valgus deformity, simple release of the contracted collateral ligament may be all that is necessary [37].
  • Imbrication of the opposite side may provide an additional measure of correction for mild varus or valgus deformity [37].
  • Satisfactory results have been reported with the use of the extensor digitorum brevis tendon rerouted underneath the transverse metatarsal ligament for varus deformity [37].
  • A competent intermetatarsal ligament is a prerequisite for the extensor digitorum brevis tendon rerouting procedure [37].
  • Ellis et al. described an extensor digitorum brevis reconstructive technique combined with a medial collateral ligament and partial plantar plate release for correction of multiplanar deformity of the second metatarsophalangeal joint [37].
  • A shortening osteotomy of the metatarsal may be necessary to correct the deformity and instability of the metatarsophalangeal joint [37].
  • A shortening osteotomy of the metatarsal will prevent the use of the extensor digitorum brevis transfer [37].
  • Klinge et al. described a modification of the Weil osteotomy to address varus or valgus angulation of the toe not corrected with simple ligament balancing [37].
  • The modified Weil osteotomy is considered particularly successful and powerful in procedures involving varus or valgus angulation of the toe not corrected with simple ligament balancing [37].
  • Joseph et al. reported a statistically significant reduction in pain, improvement in alignment, and full return to unrestricted weight-bearing activities in 31 patients with metatarsophalangeal joint fusions [37].
  • Complications of metatarsophalangeal joint fusions reported by Joseph et al. included 13% with nonunions, 6% with implant breakage, and 3% with soft-tissue infection [37].

References

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

[2] Aaos Comprehensive Orthopaedic Review 3. Anatomy and Biomechanics of the Foot and Ankle > I. Anatomy.

[3] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > BUNIONETTE DEFORMITY (TAILOR'S BUNION).

[5] Aaos Comprehensive Orthopaedic Review 3. Forefoot Disorders > IV. Deformities of the Lesser Toes.

[6] Campbell S Operative Orthopaedics 4 Volume Set. COMBINED HAMMER TOE AND MALLET TOE DEFORMITY WITH ASSOCIATED DOUBLE CORNS > TARSAL TUNNEL SYNDROME.

[7] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > ADULT HALLUX VALGUS.

[9] Campbell S Operative Orthopaedics 4 Volume Set. RESULTS OF SUTURE OF THE SCIATIC NERVE > NEUROVASCULAR ANATOMY.

[14] Rockwood And Green S Fractures In Adults. Effect of Blast on the Musculoskeletal System > Foot.

[15] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > 2. Arthrology > 3. Muscles.

[25] Aaos Comprehensive Orthopaedic Review 3. Neurologic Disorders of the Foot and Ankle > II. Interdigital Neuroma.

[28] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Foot and Ankle Reconstruction > Hallux Valgus.

[29] Apley And Solomon S Concise System Of Orthopaedics And Trauma. CONGENITAL ABNORMALITIES.

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

[32] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 10Pediatric Orthopedic Surgery > 9. Adolescent Bunions (Hallux Valgus).

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

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

[37] Campbell S Operative Orthopaedics 4 Volume Set. PERCUTANEOUS DISTAL LESSER TOE OSTEOTOMY FOR GRADE 0-I METATARSOPHALANGEAL JOINT INSTABILITY > AXIAL PLANE DEFORMITY OF THE METATARSOPHALANGEAL JOINT.

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.