Midfoot Osteotomies for the Cavus Foot

Pes cavus

Pes cavus can be defined as an abnormal elevation of the medial longitudinal arch. Historically, the condition was synonymous with being born into nobility. Ancient Chinese culture used binding techniques to create shortened, high-arched feet [3]. In 1853, Little first coined the term “pes cavus” [4]. Presently, pes cavus is often secondary to a neuromuscular disorder and associated muscle imbalance. The condition may be classified as neuromuscular, congenital, idiopathic, or traumatic. A study

Evaluation and classification

A complete history is the basis of any patient encounter, but it is of the utmost importance when a patient has pes cavus. It is important to obtain a birth history and family history and to inquire about any developmental delays [17]. In the pediatric population a cavus foot should be considered a sign of a neuromuscular disorder until proven otherwise. Treatment of any underlying disease should take precedence over treatment of the foot deformity [18].

In adults, examination of the cavus foot

Associated conditions

Several associated conditions may be present in the cavus foot. Contracted digits are one of the most common accompanying deformities. The typical contracture of the toes seen in the cavus foot led early authors on the subject to describe the deformity as clawfoot [1]. Hammertoe-type deformities in pes cavus are often caused by extensor substitution. In extensor substitution the extensor digitorum longus muscle overpowers the lumbricales during swing phase and causes dorsiflexion and retrograde

Conservative treatment

According to Mosca [18], there is little role for nonoperative treatment of the cavus foot because deformities are progressive in nature and severe by the time of presentation. An attempt should be made initially at conservative treatment. Patients with mild deformities will benefit most from conservative treatment. Operative treatment may be appropriate if there is an underlying medical condition. Nonsurgical treatment may be as simple as palliative care in the form of hyperkeratosis

Surgical intervention

Indications for surgical correction include pain, progressive deformity, and ankle instability. The goals of surgery are to balance muscle forces, correct deformities, and provide a mobile plantigrade foot [17], [18]. It is important not only to determine the apex of the deformity but to address the entire deformity. No single procedure or algorithm can be used exclusively to correct pes cavus. Surgical correction consists of soft tissue and osseous procedures. Soft tissue releases and tendon

Soft tissue procedures

Initial soft tissue procedures include plantar fascial release and Steindler stripping. Thomas [30] first reported using plantar fasciotomies for pes cavus. Later, the procedure was used alone for correction of cavus deformity caused by clubfoot and polio [31]. Today it is used primarily as an adjunct to osseous procedures. Steindler stripping is a release of the plantar fascia coupled with release of the plantar intrinsic musculature [32], [33]. Typically, the abductor hallucis, abductor

Tendon transfers

Tendon transfers are used to correct flexible deformities. A muscle should not be transferred unless its strength is at least grade 4 of 5, as transferred tendons will lose one grade in strength [35]. Transfers include the peroneous longus, posterior tibialis, and anterior tibialis. Peroneous longus transfer is indicated for a flexible plantarflexed first ray, and it is useful for any condition that causes a weak anterior tibialis muscle and dropfoot. Transfer of the peroneous longus not only

Osseous procedures

Soft tissue procedures are used for flexible deformities, and osseous correction is warranted for correction of rigid cavus foot deformities. Most osseous surgical procedures are used in conjunction with other procedures. A first metatarsal dorsiflexory wedge osteotomy is useful for treatment of a rigid plantarflexed first ray. Callus under the plantar aspect of the first metatarsal is a symptom of this fixed deformity. At our institution, a single 3.5-mm cortical screw is preferred for

Midfoot osteotomies

Midfoot osteotomies are useful in reducing rigid anterior cavus deformities. Several variations have been used over the years to enhance correction. Regardless of the level, plane, or technique of the midfoot osteotomy, the aforementioned adjunctive procedures aid in the complete correction of the deformity.

Cole procedure

Cole [1] described a closing wedge osteotomy with removal of a dorsally based wedge. The wedge is removed from a distal cut through the cuboid and cuneiforms coupled with a proximal cut through the cuboid and navicular. This elevates the forefoot out of equinus. Although Cole is credited with popularizing the procedure, it was first described by Saunders 5 years earlier [15]. The Cole procedure is indicated for rigid anterior pes cavus when the apex of the deformity is located at the midfoot.

Japas midfoot osteotomy

Japas [2] described a through-and-through V-shaped osteotomy that was designed to circumvent shortcomings of the Cole procedure, such as shortening of the foot. The technique is indicated for anterior pes cavus and serves to elevate the forefoot into a more rectus position. It is not advised in the immature foot. The tranverse plane V-shaped osteotomy is performed with the apex proximal in the navicular and the arms extending distally through the cuboid and the first cuneiform respectively [2].

Midtarsal dome osteotomy

Wilcox and Weiner [26] advocated an alternative approach for correction of rigid anterior cavus. The results of the subsequent study demonstrated a 94% satisfaction rate in patients older than 8 years of age, but only 42% satisfactory results were obtained in patients younger than 8 [26]. The procedure is indicated when the apex of the deformity lies in the midfoot. It does not aid in correction of hindfoot varus or metatarsus adductus.

Surgical technique consists of a dorsal transverse incision

Ilizarov

The Ilizarov method of external fixation is useful for correction of complex foot deformities because of its three-dimensional nature. It may be used with an accompanying midfoot osteotomy for correction of pes cavus. The osteotomy can be safely positioned across the cuboid and navicular or the cuboid and cuneiforms with fluroscopy to form a sufficient surface for bone regeneration [37], [49], [50].

Advantages of the Ilizarov method include that it is minimally invasive, thus the chance of soft

Miscellaneous midfoot osteotomies

A wide variety of lesser-known midfoot osteotomies have been advocated for the cavus foot. Giannini and associates [54] reviewed one such technique in 39 patients who were treated for idiopathic pes cavus. Treatment consisted of a cuboid osteotomy that was performed in conjunction with a naviculocuneiform fusion and a plantar fasciotomy. The study reported good or excellent results in 72% of the patients, with success being dependant on patient satisfaction and proper biomechanics of the foot

Summary

Surgical correction of the cavus foot is a challenging task. It is important to determine the apex of the deformity and to address the entire deformity. It is important to remember that no single procedure can be used exclusively to correct pes cavus. Midfoot osteotomies are an essential component of surgical correction. They can be combined with adjunctive procedures to form an appropriate strategy for the treatment of severe pes cavus.