Cavus foot deformity in children

A cavus deformity of the foot is easily recognizable, but appropriate neurologic assessment can help to determine the etiology. Cavovarus, the most frequent type of cavus foot, presents with an elevated medial longitudinal arch, first ray plantarflexion, and, if rigid, a fixed heel varus. Common causes include progressive motor sensory conditions, typically Charcot-Marie-Tooth disease, and nonprogressive conditions such as cerebral palsy and poliomyelitis. A calcaneocavus foot may be seen in poliomyelitis, spinal dysraphism, and peripheral neuropathy. Initially, the cavus deformity is flexible, but if left untreated, it becomes a fixed bony deformity. Physical examination should include the cavovarus block test, which assesses flexibility of the hindfoot deformity and can direct surgical treatment. Standing radiographs of the feet and spine, magnetic resonance imaging, and electrodiagnostic studies may be useful. Management goals are to obtain a plantigrade, mobile, pain-free, stable, motor-balanced foot. Surgical options include soft-tissue and plantar fascia releases for a flexible deformity, osteotomy for a fixed deformity, and tendon transfers to restore muscle balance. Triple arthrodesis has poor long-term results in patients with progressive deformity and sensory impairment.     

Surgical reconstruction of the paralytic flaccid foot

Flaccid paralytic deformities are secondary to muscular imbalances. Conditions affecting the muscle itself or the neurogenic control of the muscle produce muscular imbalance. Once the origin of the flaccid paralytic foot is established, factors contributing to the deformity can be identified and addressed. It is imperative to understand the natural history of the underlying disorder that causes the deformity. The treatment of the patient with a flaccid paralysis depends primarily on a thorough knowledge and understanding of the normal function of the foot gait and secondarily on a thorough understanding of the natural history of the condition to be treated. A systematic, well-planned course of treatment, either surgical or nonsurgical, needs to be developed for each patient.     

Pathophysiology of Charcot-Marie-Tooth disease

The etiology of the foot deformity in patients with Charcot-Marie-Tooth disease has not previously been discussed in relation to the extrinsic muscle function around the foot and ankle. Eight adult patients with a strong familial history were evaluated, and their foot findings were remarkably similar. All demonstrated a marked cavus deformity that was secondary to a forefoot equinus associated with contracture of the plantar fascia and a varus deformity of the calcaneus. The muscle function demonstrated marked weakness of the tibialis anterior and peroneus brevis muscles, whereas the peroneus longus and posterior calf muscles were rated as good to normal. Based on the relative strengths of these muscles and the progression of weakness, the authors hypothesize that the deformity observed in patients with Charcot-Marie-Tooth disease is secondary to the weakness of the tibialis anterior, peroneus brevis, and the intrinsic muscles, with their natural antagonists, the peroneus longus and the tibialis posterior muscles causing most of the deformity noted in these adult patients.     

Tarsal coalition: review and preliminary conclusions

Tarsal coalition is a relatively rare anomaly, and the degree of fusion between two or more tarsal bones varies. The coalition may be osseous, cartilaginous or fibrous, and it may be complete or incomplete. It usually results in rigid planovalgus deformity of the foot and may be associated with secondary spasm of the peroneal muscle group. With few exceptions, complete stabilization by arthrodesis is the treatment of choice.     

Cavovarus Foot Deformity With Multiple Tarsal Coalitions: Functional and Three-Dimensional Preoperative Assessment

In rare instances, tarsal coalition leads to cavovarus foot deformity, although the pathologic mechanism leading to this deformity is not clear. This article reports a case of a 14-year-old boy presenting a severe cavovarus deformity of the right foot with talocalcaneal and calcaneonavicular coalitions, and a mild cavus deformity of the left foot with a single talocalcaneal coalition. Computed tomography and postoperative histologic analysis demonstrated a synostosis between talus and calcaneus and a fibrous calcaneonavicular coalition with partial ossification. Instrumented gait analysis revealed a limited range of ankle plantar flexion and increased external rotation of the ankle. Associated skeletal malformations including incomplete hemimelia of the forearm and scoliosis raised the possibility of a teratologic condition, but neurologic examination, spinal magnetic resonance imaging, and nerve conduction velocities were normal. The progressive ossification of combined coalitions during growth of the foot may have been one factor leading to this complex foot deformity. The fine-wire electromyogram showed normal tibialis anterior and posterior muscle activity. Small soft tissue tears in the sinus tarsi may have led to a mild reflexive increase of the muscle tone and tendon shortening, which pulled the forefoot into adduction and the heel into varus, and raised the medial arch. Mechanical alterations of the ankle appear secondary to the heel varus and to the progressive deformity of the talus. Three-dimensional computed tomography reconstruction and gait analysis appeared to be helpful additional parameters to understanding the pathomechanics of this complex foot deformity and for preoperative planning of triple arthrodesis.     

Anatomy of the varus foot and ankle

In summary, varus deformity of the foot and ankle encompasses a spectrum of deformities from mild to severe. The cause of this deformity may be bone, muscle imbalance, or a combination of both. Surgical intervention should be planned only after the patient's anatomy is understood. Uncorrected symptomatic varus deformities may have significant consequences on gait kinematics and foot biomechanics.     

Pediatric issues with cavovarus foot deformities

Cavovarus foot deformity in children has numerous etiologies with a general pathophysiologic mechanism of muscle imbalance. It is of great importance in the evaluation of a child with a cavovarus foot to determine the underlying cause of the deformity, as the most common origin is a progressive neurologic condition that may be complicated by other orthopedic problems. Treatment options typically are surgical, with limited indications for nonsurgical modalities, and must consider the age of the patient, the nature of the neurologic disease, and the severity of the deformity. Current surgical procedures can be divided into soft tissue procedures to rebalance the muscle forces, osteotomies, and triple arthrodesis. Triple arthrodesis is considered a salvage procedure reserved for the older child with severe, rigid deformity who has failed other surgical treatments.     

Current concepts of Charcot foot in diabetic patients

The Charcot foot is an uncommon complication of neuropathy in diabetes. It is a disabling and devastating condition. The etiology of the Charcot foot is unknown, but it is characterized by acute inflammation with collapse of the foot and/or the ankle. Although the cause of this potentially debilitating condition is not known, it is generally accepted that the components of neuropathy that lead to foot complications must exist. When it is not detected early, a severe deformity will result in a secondary ulceration, infection, and amputation. Immobilization in the early stages is the key for success, but severe deformity may still develop. When severe deformity is present, bracing may be attempted but often patients will need surgical intervention. Good success has been shown with internal and external fixation. In patients with concomitant osteomyelitis, severe deformity, and/or soft tissue infection, a high amputation may be the best treatment of choice.     

Reconstructive measures for the foot after compartment syndrome]

Following severe indirect and/or direct trauma to the foot, compartment syndrome can easily develop in this foot. Untreated, the compartment syndrome results in a complex post-traumatic deformity--the "short foot syndrome." This may manifest itself as a contracted pes equinovarus foot with clawing of the toes. Isolated compartment syndrome of the foot due to local injury may result in the formation of hammer toes. During childhood and adolescence, severe soft tissue injuries to the lower leg or foot, with subsequent compartment syndrome of the foot or a neurovascular injury to the lower limb, may result in an alteration in growth of the affected region or may involve the foot. Radiological assessment of this contracted "short foot" using sonography or MRI demonstrates scarred, necrotic musculature mainly involving the muscles of the posterior tibia, the flexor hallucis and the flexor digitum. Muscular imbalance due to long-standing muscle palsies, or chronic post-traumatic osteitis of the tibia contribute to the development of rigid equinus foot and ankle. Treatment of the contracted foot includes complex soft tissue release, muscle and tendon transfer, tendon-lengthening procedures, and intrinsic releases to correct the toe deformities. In the adult with a severe post-traumatic pes equino-varus deformity, triple arthrodesis is recommended.     

Linear scleroderma and foot deformity in children

Linear scleroderma is a subtype of localized scleroderma generally observed in children, and may produce secondary bone and joint deformities. Its localization at the foot or ankle is rarely reported. A complete review of the literature reveals 21 cases of foot or ankle deformity due to linear scleroderma to which we add one case. The clinical and radiological aspects of the deformity, its pathogenesis, histological findings as well as orthopaedic management are presented and discussed.     

Medial ankle instability

Medial instability is suspected on the basis of a patient's ankle feeling like it is "giving way," especially medially, when walking on uneven ground, downhill, or down stairs, pain at the anteromedial aspect of the ankle, and sometimes pain in the lateral ankle, especially during dorsiflexion of the foot. A history of a chronically unstable feeling that is manifested by recurrent injuries with pain, tenderness, and sometimes bruising over the medial and lateral ligaments, is considered to indicate combined medial and lateral instability that is believed to result in rotational instability of the talus in the ankle mortise. Pain on the medial gutter of the ankle and a valgus and pronation deformity of the foot are hallmarks of the disorder. The deformity typically can be corrected by the activation of the posterior tibial muscle. In contrast to stress radiographs, arthroscopy is a helpful diagnostic tool in verifying medial instability; it proved that the lateral ankle ligaments also can be involved. The treatment for symptomatic medial instability of the ankle might include reconstruction of all involved ligaments at the medial, and, if necessary, the lateral ankle. In the case of progressed foot deformity or bilateral long-standing valgus and pronation deformity of the foot, an additional calcaneal lengthening osteotomy might be considered. A classification of the instability into three types has been helpful for determining surgical treatment and the after treatment. This treatment concept provides high patient satisfaction and reliable clinical results.     

Cavovarus foot treated with combined calcaneus and metatarsal osteotomies

Twenty-one feet in fifteen patients underwent osteotomies of the calcaneus and one or more metatarsals for symptomatic cavovarus foot deformity. Seven (nine feet) were male, and eight (twelve feet) were female. The etiology included hereditary motor sensory neuropathy (HMSN) (fifteen feet), post-polio syndrome (two feet), sacral cord lipomeningocele (two feet), parietal lobe porencephalic cyst (one foot), and idiopathic peripheral neuropathy (one foot). Presenting complaints were metatarsalgia (fifteen feet), ankle instablility (five), and ulceration beneath the second metatarsal head (one foot). Eleven feet were assessed using the Maryland Foot Rating Score. Maryland Foot Rating Score (University of Maryland, Baltimore, MD) improved from 72.1 (avg.) preoperatively to 89.9 (avg.) post-operatively (follow-up 70.9 months avg.). Eight feet were assessed using the AOFAS (American Orthopaedic Foot and Ankle Society) Ankle-Hindfoot and Midfoot Scores. The AOFAS Ankle-Hindfoot Score improved from 46.3 (avg.) pre-operatively to 89.1 (avg.) post-operatively, and the AOFAS Midfoot Score improved from 40.9 (avg.) pre-operatively to 88.8 (avg.) post-operatively (follow-up 20.8 months avg.). The postoperative AOFAS Ankle-Hindfoot Score for all nineteen feet was 90.8 (avg.) and the post-operative AOFAS Midfoot Score for all nineteen feet was 90.2 (avg.). Two patients were lost to follow-up and were not included in the study. Ankle, hindfoot, and midfoot motion was maintained or improved in sixteen feet. Complications included delayed union in two and nonunion in three of 66 metatarsal osteotomies. While three patients required an AFO (ankle-foot orthosis) for ambulation preoperatively, all patients were brace free postoperatively. All patients expressed willingness to undergo the same procedure again if it were necessary. Weight-bearing radiographs were available for 17 feet. Radiographic analysis revealed a decrease in forefoot adduction (9.6 degrees avg.) and a reduction in both hindfoot (9.1 degrees avg.) and forefoot cavus (10.6 degrees) leading to an overall 13 percent reduction in the height of the longitudinal arch. Lateral sliding elevating calcaneal osteotomy combined with dorsolateral closing wedge osteotomies of one or more metatarsal bases in the severe symptomatic cavovarus foot can provide a pain-free, plantigrade foot with a lowered longitudinal arch and a stable ankle without sacrificing motion.     

Lateral-sided bony procedures

Treatment of any hindfoot deformity should include correction of the deformity and preservation of complex hindfoot motion. This important motion is protective of adjacent, and more removed, joints in that it serves a shock-absorbing function and protects them from stresses. Lateral column lengthening combined with a medial soft-tissue procedure is the treatment of choice for stage II flat foot. Patients who have significant subluxation of the subtalar joint will also need a medial displacement calcaneal osteotomy to correct the hindfoot valgus. Only patients who have a rigid foot secondary to degenerative changes will require an arthrodesis to correct the deformity and provide pain relief. Unfortunately, although fusion works well to correct deformity, it accelerates future degenerative changes.     

Spinal dysraphism and cavovarus foot deformity: a case report

Neurological impairment secondary to spinal dysraphism most commonly presents as unilateral cavovarus foot in children. The deformity usually develops in the growing child around the age of five or six. The presence of a cavovarus foot of unknown origin in a child should lead to a complete neurological examination, including an assessment of the spine for spinal dysraphism. The early recognition of pathology may prevent severe neurological sequelae. A case of lipomyelomeningocele is presented to illustrate that cord damage in children with spinal dysraphism can present initially as a cavovarus foot.     

Spastische Fußdeformitäten im Kindesalter

Although the neurological defects associated with cerebral palsy are not progressive, secondary musculoskeletal disorders due to growth and gravity are variable. In the clinical analysis of spastic foot deformities different mechanisms that produce a variety of deformities have to be analyzed. The goals of surgical treatment are correction of the deformity, reestablishment of stability of the foot and preservation of functionally important ranges of motion and muscle strength. The most common spastic foot deformities are equinus, planovalgus, equinovarus and calcaneus. For treatment soft tissue surgery, such as muscle lengthening and transfer together with bone surgery, such as osteotomy or arthrodesis are used and combinations of these methods are often required. Subsequently postoperative plasters are necessary followed by dynamic orthotic management.     

Selective botulinum toxin injection in the treatment of recurrent deformity following surgical correction of club foot: a preliminary report of 3 children

Management of a child with club foot deformity that recurs after an apparently successful posteromedial soft tissue release remains a challenge. Revision surgery is often attempted, but this carries a high risk of significant scarring or neurovascular complications. We have treated 3 children (3 feet) with relapsed club foot and fixed deformities, using Botulinum toxin A (BTX-A) injection into muscle groups clinically thought to be responsible for recurrent deformity, followed by moulded plaster casts. Two cases have maintained a good foot position with an minimum follow-up of 18 months, and one other is also doing well having had a tibialis anterior tendon transfer as well as the BTX-A therapy. In our limited experience, targeted BTX-A injection with plaster casting has been safe, and may obviate the need for major revision surgery in a proportion of cases with recurrent club foot deformity following previous posteromedial soft tissue release.     

Selective botulinum toxin injection in the treatment of recurrent deformity following surgical correction of club footA preliminary report of 3 children

Management of a child with club foot deformity that recurs after an apparently successful posteromedial soft tissue release remains a challenge. Revision surgery is often attempted, but this carries a high risk of significant scarring or neurovascular complications. We have treated 3 children (3 feet) with relapsed club foot and fixed deformities, using Botulinum toxin A (BTX-A) injection into muscle groups clinically thought to be responsible for recurrent deformity, followed by moulded plaster casts. Two cases have maintained a good foot position with an minimum follow-up of 18 months, and one other is also doing well having had a tibialis anterior tendon transfer as well as the BTX-A therapy. In our limited experience, targeted BTX-A injection with plaster casting has been safe, and may obviate the need for major revision surgery in a proportion of cases with recurrent club foot deformity following previous posteromedial soft tissue release.     

Current topics review: Charcot neuroarthropathy of the foot and ankle

Charcot arthropathy is a destructive process, most commonly affecting joints of the foot and ankle in diabetics with peripheral neuropathy. Affected individuals present with swelling, warmth, and erythema, often without history of trauma. Bony fragmentation, fracture, and dislocation progress to foot deformity, bony prominence, and instability. This often causes ulceration and deep infection that may necessitate amputation. Instability or deformity may limit the ability to use standard footwear. Treatment is focused on providing a stable and plantigrade foot for functional ambulation with accommodative footwear and orthoses. Historically, treatment had included nonweightbearing immobilization for the acute phase, and surgery had been reserved only for infection, unresolved skin ulceration, or deformity that precluded the use of therapeutic footwear. Current controversies include weightbearing in the acute or reparative phases and early surgical stabilization. Foot-specific patient education and continued periodic monitoring may reduce the morbidity and associated expense of treating the complications of this disorder and may improve the quality of life in this complex patient population.     

Combined split anterior tibial-tendon transfer and intramuscular lengthening of the posterior tibial tendon. Results in patients who have a varus deformity of the foot due to spastic cerebral palsy

Twenty patients who had a varus deformity of the foot secondary to spastic cerebral palsy had twenty-two operations involving combined split anterior tibial-tendon transfer and intramuscular lengthening of the posterior tibial tendon, with and without concomitant lengthening of the Achilles tendon. Preoperatively, all patients had had a dynamic varus deformity of the hindfoot and adduction of the forefoot in both the stance phase and the swing phase of gait. At an average follow-up of 6.2 years (range, 2.3 to 8.8 years), there were fourteen excellent, four good, and four poor clinical results. Two patients who had a fixed varus deformity of the hindfoot and one patient who had a very weak anterior tibial muscle had a poor result. We concluded that the combined procedure is effective for correction of a flexible varus deformity of the foot in patients who have spastic cerebral palsy.     

Split tibialis posterior tendon transfer on peroneus brevis for equinovarus foot in CP children]

Equinovarus deformity of the foot is a result of the muscles imbalance in which inventors of the foot, mostly posterior and anterior tibialis muscle, overpower evertors. In children with cerebral palsy untreated spastic equinovarus deformity may cause severe fixed foot deformity and painful callosities under metatarsal heads and on the lateral side of the foot. The gait pattern becomes less effective and needs more energy. The study group consisted of 154 children with cerebral palsy treated in our Clinic by the multilevel soft tissue surgery. For foot problems 136 children needed surgical intervention. In 19 ambulatory patients, with hemiplegia or diplegia, split tibialis posterior tendon transfer together with tendo Achilles lengthening and plantar aponeurectomy were performed. The study was based on clinical examination, parents' questionnaire, radiology and gait analysis at least one year after surgery. The mean follow up was 4.6 years. The functional improvement was observed in 17 (89%) children with tendon transfer. At the last follow up those patients were brace free, with plantigrade foot while walking (without DAFO orthesis) and normal shoes were used. All painful callosities disappeared. On a standing AP X-ray adequate correction of the hindfoot-forefoot relation was achieved in 14 (74%) cases. Persistent equinovarus deformity over 10 degrees was observed in 2 cases. Those patients underwent additional bone surgery. With a properly planned approach the split tibialis posterior tendon transfer can bring good clinical and functional results in CP children with equinovarus deformation. We recommend this procedure in early stage of the deformity what can eliminate more harmful triple arthrodesis in severe deformities.