Forefoot Morphotypes in Cavovarus Feet: A Novel Assessment of Deformity.

BACKGROUND: The cavovarus foot is a complex 3-dimensional deformity. Although a multitude of techniques are described for its surgical management, few of these are evidence based or guided by classification systems. Surgical management involves realignment of the hindfoot and soft tissue balancing, followed by forefoot balancing. Our aim was to analyze the pattern of residual forefoot deformities once the hindfoot is corrected, to guide forefoot correction. METHODS: We included 20 cavovarus feet from 16 adult patients with Charcot-Marie-Tooth who underwent weightbearing CT (mean age 43.4 years, range: 22-78 years, 14 males). Patients included had flexible deformities, with no previous surgery. Using specialized software (Bonelogic 2.1, Disior) a 3-dimensional, virtual model was created. Using morphologic data captured from normal feet in patients without pathology as a guide, the talonavicular joint of the cavovarus foot was digitally reduced to a "normal" position to simulate the correction that would be achieved during surgical correction. Models of the corrected position were exported and geometrically analyzed using Blender 3.64 to identify anatomical trends. RESULTS: We identified 4 types of cavovarus forefoot morphotypes. Type 0 was defined as a balanced forefoot (2 cases, 10%). Type 1 was defined as a forefoot where the first metatarsal was relatively plantarflexed to the rest of the foot, with no significant residual adduction after talonavicular joint correction (12 cases, 60%). Type 2 was defined as a forefoot where the second and first metatarsals were progressively plantarflexed, with no significant adduction (4 cases, 20%). Type 3 was defined as a forefoot where the metatarsals were adducted after talonavicular derotation (2 cases, 10%). CONCLUSION: In this relatively small cohort, we identified 4 forefoot morphotypes in cavovarus feet that might help surgeons to recognize and anticipate the residual forefoot deformities after hindfoot correction. Different treatment strategies may be required for different morphotypes to achieve balanced correction. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Classifications in adult pes cavus - A scoping review.

AIMS: The adult cavus foot represents a challenging clinical problem, with varied aetiology and complex, 3-dimensional deformities. Thus far, the cavus foot has eluded a unified classification. The aim of this paper was to appraise the literature to identify classification systems which guide the operative management of neurological cavus feet in adults. METHODS: As the aim of this paper was broad, a scoping review was conducted. The review was conducted in line with published frameworks. Our principal research question was 'what classification systems that guide surgical management currently exist for neurological cavus feet in adults'. We searched CINAHL, Embase, OVID, Proquest, Pubmed, Scopus and Web of Science databases using MESH and non-MESH terms. Two authors independently reviewed abstracts / papers and a data extraction sheet was used to collect the relevant data. RESULTS: A total of 1140 articles were initially screened, identifying 125 articles for which a full text review was performed. Only three articles met all our inclusion criteria. All these articles reported an anatomical classification with suggestions for treatment based on the classification. All were considered to comprise Level V evidence, and none reported outcomes of treatment based on the classification. CONCLUSIONS: There is currently a paucity of robust classifications to guide treatment in neurological cavus feet in adults. The few classifications systems that exist are varied and do not as yet have sufficient evidence to support their widespread use. Further work is required, aimed at identifying specific features of cavus feet that would guide operative treatment.

3D Analysis of Joint-Sparing Charcot-Marie-Tooth Surgery Effect on Initial Standing Foot Alignment.

BACKGROUND: The complex deformities in cavovarus feet of Charcot-Marie-Tooth (CMT) disease are difficult to evaluate. The aim of this study was to quantify the initial standing alignment correction achieved after joint-sparing CMT cavovarus reconstruction using pre- and postoperative weightbearing computed tomography (WBCT). METHODS: Twenty-nine CMT cavovarus reconstructions were retrospectively analyzed. Three-dimensional measurements were performed using semiautomated software (Bonelogic 2.1) to investigate changes in sagittal, axial, and coronal parameters. Pre- and postoperative data were compared, along with normative data. Correlation among the preoperative measurements and the amount of correction in sagittal, axial, and coronal parameters were analyzed. RESULTS: The sagittal, axial, and coronal malalignment of the hindfoot, and the sagittal and axial malalignment of the forefoot, was significantly improved after corrective surgery (P < .05). Sagittal Meary angle (from 14.8 to 0.1 degrees), axial talonavicular angle (TNA, from 3.6 to 19.2 degrees), and coronal hindfoot alignment (from 11.0 to -11.1 degrees) showed significant changes postoperatively (P < .001). Hindfoot, forefoot sagittal, and forefoot axial parameters reached comparable outcomes compared with normative value (P > .05). Regarding amount of correction, Spearman correlation demonstrated that axial Meary angle and TNA were most strongly related to improvement in sagittal Meary angle and coronal hindfoot alignment. CONCLUSION: Preoperative and postoperative WBCT measurements demonstrated that joint sparing CMT cavovarus reconstruction significantly improved sagittal, axial, and coronal deformities of CMT, and sagittal Meary angle was restored toward normative values. Apparent axial plane correction, the majority of which occurred at the talonavicular joint, had the strongest correlation with deformity correction in multiple planes. This suggests that soft tissue releases and correction of the talonavicular joint may be a key component of a cavovarus foot correction.

Managing the Severe Cavus Foot Deformity in Global Humanitarian Programs.

The cavus foot represents a complex spectrum of deformity ranging from the subtle idiopathic to the severe sensorimotor neuropathy and other neuromuscular deformities. The successful surgical treatment of the cavus foot depends on a fundamental understanding of the underlying multiplanar deformity, inherent muscle balance, and the rigidity of the hindfoot. The location of the deformity is described and understood according to its multiple apices. These deformities are addressed with osteotomies or arthrodesis directed at the apices of deformity. Simultaneously, correction of muscular imbalances with appropriate tendon transfers must also be performed to prevent recurrent deformity. With these principles in mind, the surgical correction of the cavus foot becomes simplified and algorithmically driven.

The Role Of Minimally Invasive Osteotomies In Cavovarus Foot Reconstruction: Detailed Technique And Evidence For Procedures.

Percutaneous correction of cavus foot deformity can be achieved with satisfactory correction of foot anatomy and biomechanics. Surgical management of cavovarus foot reconstruction is an individualized combination of surgical procedures designed to correct deformity. Minimally invasive procedures using high-torque low-speed burr can facilitate large deformity correction without extensive soft tissue stripping. This article presents the operative technique for percutaneous cavus foot correction including a lateralizing calcaneal osteotomy and proximal first ray osteotomy. However, methodologically robust evidence to support this procedure is lacking at present, and further research, particularly, focusing on long-term clinical outcomes and follow-up is required.

Is Subtle Cavovarus a Problem for Athletes?

Cavovarus or high-arched foot is a common foot deformity that occurs due to the disruption of the foot-driven equilibrium between the first metatarsal, fifth metatarsal, and the heel. This imbalance leads to an increase in the foot's normal plantar concavity. Cavovarus deformity ranges from a mild and flexible malalignment to a fixed, complex, and severe deformation. Subtle cavovarus foot, the mild form of the cavus foot, was first described by Manoli and colleagues.

Toes Deformities in Cavovarus: How to Approach Them.

Sagittal lesser toe deformities (LTD) are the most common in cavus foot. They are mainly the result of muscular imbalance between intrinsic and extrinsic muscles. Surgery is the second-line treatment if medical treatment fails. The aim of the present study was to provide an update on classification and surgical management of LTD in cavus foot including percutaneous procedures with a special focus on sagittal deformities. Joint sparing procedures are preferred for reducible LTD, whereas lesser toe fusions are used for rigid one in association with tendon transfer or percutaneous procedures depending of surgeon's experience and patient's clinical examination.

Ankle Instability and Peroneal Disorders in Cavovarus Feet: Do I Need a Calcaneal Osteotomy?

In order to understand the relation among ankle instability, peroneal disorders, and cavovarus deformity, it is mandatory to clarify the different stages of those disorders and also to put them into relation to each other. Finally, we need to take the patients compliance and expectations into consideration to define the individually right way of treatment.

Hindfoot Fusions in the Cavovarus Foot: What Is the Key for a Successful Outcome?

The aim of hindfoot fusions in the cavovarus foot is to establish a painless, plantigrade, balanced and stable foot. A comprehensive clinical and radiographic assessment enables the surgeon to fully understand the patient's deformity and plan a reliable surgical strategy for deformity correction. Pre-operative planning and intraoperative techniques are discussed.

Supramalleolar Osteotomies in Cavovarus Foot Deformity: Why Patient-Specific Instruments Make a Difference.

Supramalleolar osteotomy enables correction of the ankle varus deformity and is associated with improvement of pain and function in the short term and long term. Despite these beneficial results, the amount of surgical correction is challenging to titrate and the procedure remains technically demanding. Most supramalleolar osteotomies are currently planned preoperatively on 2-dimensional weight-bearing radiographs and executed peroperatively using free-hand techniques. This article encompasses 3-dimensional planning and printing techniques based on weight-bearing computed tomography images and patient-specific instruments to correct ankle varus deformities.

Double and Triple Tarsal Fusions in the Complex Cavovarus Foot.

The cavovarus (cavus) foot is one of the most perplexing and challenging of all foot deformities and may prove to be one of the most difficult conditions to treat. This deformity is characterized by increased plantar flexion of the forefoot and midfoot in relation to the hindfoot resulting in high foot arch. Because cavus foot rarely occurs in an isolated form, the term "cavus foot" rather describes a part of a complex multiplanar foot deformity. Because the underlying disease is mostly neurogenic characterized by muscle imbalance in almost every case a combined bony and soft tissue surgery is inevitable.

Joint preserving procedures for painful plantar callosities in patients with flexible cavovarus foot.

BACKGROUND: The outcome of a constant joint preserving procedure for painful plantar callosities with cavovarus foot remains unclear. METHODS: Eleven patients (11 feet) who underwent lateral displacement calcaneal osteotomy (LDCO), dorsiflexion first metatarsal osteotomy (DFMO), and plantar fasciotomy (PF), simultaneously were included. The presence of painful callosities, heel alignment of standing (HA), and the Japanese Society for Surgery of the Foot ankle/hindfoot (JSSF) score were evaluated. Radiographically, the talonavicular coverage angle (TNCA), lateral talo-first metatarsal angle (LTMA), calcaneal pitch angle (CPA), and heel alignment angle (HAA) were measured. RESULTS: Postoperatively, painful plantar callosities disappeared in 10 patients and remained in one patient. The postoperative HA and JSSF score significantly improved. The postoperative TNCA, LTMA, CPA, and HAA significantly improved. CONCLUSIONS: In patients with flexible cavovarus foot, LDCO, DFMO, and PF yielded good outcomes at mid-term follow-up with preservation of the foot and ankle joints.

Pes Cavus Deformity: Anatomic, Functional Considerations, and Surgical Implications.

Pes cavus is a complicated, multiplanar deformity that requires a thorough understanding in order to provide the appropriate level of care. The foot and ankle surgeon should perform a comprehensive examination, including a neurologic evaluation, in the workup of this patient population. Understanding the cause of the patient's deformity is a critical step in predicting the disease course as well as the most acceptable form of treatment. The surgical correlation with the patient's pathologic anatomy requires an in-depth clinical evaluation, in addition to the radiographic findings, as the radiographic findings do not necessarily correlate with the patient's discomfort.

Neurologic Conditions Associated with Cavus Foot Deformity.

The cavus foot deformity is an often less understood deformity within the spectrum of foot and ankle conditions. The hallmark concern is the possibility of an underlying neurologic or neuromuscular disorder. Although a proportion of these deformities are idiopathic, a significant majority do correlate with an underlying disorder. The appropriate evaluation of this deformity, in coordination within the multidisciplinary scope of health care, allows for a timely diagnosis and understanding of the patient's condition. We provide an abbreviated survey of possible underlying etiologies for the patient with the cavus foot deformity as a reference to the foot and ankle surgeon.

Hallux and Lesser Digits Deformities Associated with Cavus Foot.

It is important to identify the level of the deformity or deformities. It is important to get the limb as close to anatomic alignment as possible. Many levels and multiple procedures may be involved with this reconstruction.

Use of Calcaneal Osteotomies in the Correction of Inframalleolar Cavovarus Deformity.

Cavovarus deformity is a complicated condition most commonly resulting from neurologic, posttraumatic, or iatrogenic pathologic conditions. Careful evaluation of the cavovarus patient is necessary in determining appropriate treatment course. Weight-bearing radiographs are necessary, and advances in computed tomographic technology can be beneficial in identifying level of involvement. In the case of operative treatment of inframalleolar deformity, assessment of the subtalar joint position and relation of calcaneocuboid joint can be of assistance. Multiple osteotomies have been described providing uniplanar, biplanar, and triplanar correction and in the appropriate setting can prove beneficial to the surgeon in treating hind-foot cavovarus deformity.

Principles of Triple Arthrodesis and Limited Arthrodesis in the Cavus Foot.

Cavus foot is a complex podiatric deformity that requires precise and in-depth work-up through an objective, physical, and radiographic examination. The goal of surgical treatment is to eliminate pain while establishing a plantigrade foot structure. Triple arthrodesis has proven to be an effective surgical procedure for treatment of moderate to severe rearfoot deformity with or without the presence of rearfoot arthritic changes. The foot and ankle surgeon must always be aware that no two cavus deformity cases are alike, therefore one may require additional surgical procedures including soft tissue balancing, joint-sparing osteotomies, and/or supplementary arthrodesing procedures.

Tendon Transfers and Their Role in Cavus Foot Deformity.

Management of the cavus foot is a difficult task for the foot and ankle surgeon. Tendon transfers have been a longstanding accepted treatment for the flexible cavus foot. Performing tendon transfers requires an in-depth understanding of the patient's medical history, factors leading to the development of deformity, as well as the deforming forces contributing to the deformity. Evaluation of the patient for rigid, progressive, and/or spastic deformities is critical to avoid postoperative complications. Educating the patient on postoperative rehabilitation, potential complications, and postoperative expectations is essential to ensure appropriate surgical outcomes.

The Role of Peroneal Tendinopathy and the Cavovarus Foot and Ankle.

Peroneal tendon pathology is often an overlooked and underdiagnosed condition. It is often confused with chronic ankle instability. It is important when surgically managed to assess the condition of the tendons, muscle viability and strength, and associated cavovarus deformity. Complex reconstruction may be needed, including 2-stage procedures with a silicone rod and tendon transfer.

Ankle and Pantalar Arthrodesis: End-Stage Salvage in Cavus Foot.

Bony alignment is the primary goal in foot and ankle reconstruction of the cavovarus foot. This condition presents as a malalignment causing a medial overload of the ankle articular surface and lateral overload of the hindfoot, midfoot, and forefoot. A painful gait associated with articular degeneration of the numerous joints can lead to a chronic and rigid arthrosis of joints, warranting arthrodesis of the affected joints accordingly.