The Reliability of Common Radiographic Measurements Used to Describe Foot Deformities.

Radiographic measurements are frequently used to classify deformity and determine treatment options. Correlation coefficients can be used to determine inter- and intrarater reliability. Reliability is a required feature of any measurement if the measurement is to provide valid information. We calculated correlation coefficients for standard radiographic measurements used to categorize foot deformities: this was done for 52 sets of radiographs assessed by 5 raters. We aimed for generalizability, and kept rater instructions to match what was originally published for each measurement of interest with schematic illustration. Overall, our results mostly showed a lack of inter-rater reliability (correlation coefficients <0.4), and strong intrarater reliability (correlation coefficients >0.6), for 12 forefoot and 12 rearfoot radiographic measurements that are commonly used. The results of this investigation bring into question the routine use of radiographic measurements to categorize deformity, select treatments, and measure surgical outcomes, between surgeons, because the validity of these measurements appears to be threatened by weak inter-rater reliability. In order for these measurements to be considered useful, it may be necessary for surgeons to more rigorously define and practice making standard radiographic measurements.

Medializing Calcaneal Osteotomy for progressive collapsing foot deformity alters the three-dimensional subtalar joint alignment.

BACKGROUND: A medializing calcaneal osteotomy (MCO) is considered as one of the key inframalleolar osteotomies to correct progressive collapsing foot deformity (PCFD). While many studies were able to determine the post-operative hind- and midfoot alignment, alternations of the subtalar joint alignment remained obscured by superposition on plain radiography. Therefore, we aimed to assess the hind-, midfoot- and subtalar joint alignment pre- compared to post-operatively using 3D weightbearing CT (WBCT) imaging. METHODS: Seventeen patients with a mean age of 42 ± 17 years were retrospectively analyzed. Inclusion criteria consisted of PCFD deformity corrected by a medializing calcaneal osteotomy (MCO) as main procedure and imaged by WBCT before and after surgery. Exclusion criteria were patients who had concomitant calcaneal lengthening osteotomies, mid-/hindfoot fusions, hindfoot coalitions, and supramalleolar procedures. Image data were used to generate 3D models and compute the hindfoot (HA), midfoot (MA) - and subtalar joint (STJ) alignment in the coronal, sagittal and axial plane, as well as distance maps. RESULTS: Pre-operative measurements of the HA and MA improved significantly relative to their post-operative equivalents p < 0.05). The post-operative STJ alignment showed significant inversion (2.8° ± 1.7), abduction (1.5° ± 1.8), and dorsiflexion (2.3° ± 1.7) of the talus relative to the calcaneus (p < 0.05) compared to the pre-operative alignment. The displacement between the talus and calcaneus relative to the sinus tarsi increased significantly (0.6 mm±0.5; p < 0.05). CONCLUSION: This study detected significant changes in the sagittal, coronal, and axial plane alignment of the subtalar joint, which corresponded to a decompression of the sinus tarsi. These findings contribute to our clinical practice by demonstrating the magnitude of alteration in the subtalar joint alignment that can be expected after PCFD correction with MCO as main procedure.

What's the clinical significance of VAS, AOFAS, and SF-36 in progressive collapsing foot deformity.

BACKGROUND: This study aimed to ascertain the minimal clinically important difference (MCID), and substantial clinical benefit (SCB) of the American Orthopedic Foot and Ankle Society (AOFAS) scale, visual analog scale (VAS) for pain, and Short Form-36 Health Survey (SF-36) in progressive collapsing foot deformity (PCFD) surgery. METHODS: In this retrospective cohort study, a total of 84 patients with PCFD (84 feet) who underwent surgery between July 2015 and April 2021 were included. The study assessed the patients' subjective perception, as well as their VAS, AOFAS, and SF-36 scores at a minimum two-year follow-up, and these data were subjected to statistical analysis. The study utilized Spearman correlation analysis to determine the degree of correlation between patients' subjective perception and their VAS, AOFAS, and SF-36 scores. The minimal detectable change (MDC), MCID, and SCB for VAS, AOFAS, and SF-36 were calculated using both distribution- and anchor-based methods. The classification outcomes obtained from the distribution- and anchor-based methods were assessed using Cohen's kappa. RESULTS: Based on the subjective perception of the patients, a total of 84 individuals were categorized into three groups, with 7 in the no improvement group, 14 in the minimum improvement group, and 63 in the substantial improvement group. Spearman's correlation analysis indicated that the patients' subjective perception exhibited a moderate to strong association with VAS, AOFAS, SF-36 PCS, and SF-36 MCS, with all coefficients exceeding 0.4. The MCID of VAS, AOFAS, SF-36 PCS, and SF-36 MCS in PCFD surgery were determined to be 0.93, 5.84, 4.15, and 4.10 points using the distribution-based method and 1.50, 10.50, 8.34, and 3.03 points using the anchor-based method. The SCB of VAS, AOFAS, SF-36 PCS, and SF-36 MCS in PCFD surgery were 2.50, 18.50, 11.88, and 6.34 points, respectively. Moreover, the preliminary internal validation efforts have demonstrated the practical application and clinical utility of these findings. With the exception of the distribution-based MCID of SF-36 PCS, which showed fair agreement, all other measures demonstrated moderate to almost perfect agreement. CONCLUSIONS: The MDC, MCID, and SCB intuitively enhance the interpretation of VAS, AOFAS, and SF-36 in PCFD surgery, assisting all stakeholders to better understand the therapeutic benefits and limitations of clinical care, and thus to make a more rational decision. Each of these parameters has its own emphasis and complements the others. These parameters are recommended for evaluating the clinical relevance of the results, and their promotion should extend to other areas of foot and ankle surgery.

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.

Neonatal Assessment: Put Your Best Foot Forward.

BACKGROUND: Assessment of the foot is an essential part of the newborn examination. Foot abnormalities range from an isolated deformity due to intrauterine positioning to a functional impairment due to a structural malformation. The purpose of this article is to review assessment, abnormal findings, and current treatment options of common foot deformities. EVIDENCE ACQUISITION: A review of literature was conducted using keywords in PubMed, Google Scholar, and CINAHL databases from 2018 to 2023. RESULTS: Although assessment techniques for the neonatal foot remain the same, recent nonsurgical treatment options are available for a variety of neonatal foot deformities. Early recognition allows for proper evaluation of foot deformities and corrective measures. IMPLICATIONS FOR PRACTICE AND RESEARCH: Neonatal providers equipped with knowledge of common foot problems can provide support and anticipatory guidance to families.

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.

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.

Managing Cavovarus Feet in Diabetic Patients.

A cavovarus foot is characterized by exacerbated medial longitudinal arch (cavus), hindfoot varus, plantar flexed first ray, forefoot pronation (apparent supination), forefoot adduction, and claw toe deformities. It can be broadly divided as flexible and rigid and further classified based on the neurological and non-neurological causes. Diabetes associated peripheral neuropathy complicates individual bony deformities associated with cavovarus foot with early callus which can breakdown to ulceration rapidly. Based on the disease progression in neurological and non-neurological causes of cavovarus feet in patients with diabetic neuropathy, 3 stages of the disease and its management is described.

Complex rigid foot deformity correction with hexapod external fixator system.

PURPOSE: Complex rigid foot deformities include three-plane deformities and usually presents with poor soft tissue coverage. In the last decades, gradual correction with computer-assisted fixator became an appropriate option for the treatment rigid foot deformities. This study aims to report our experience about treatment of complex foot deformities using Smart Correction fixator system®. METHODS: We retrospectively analyzed 13 complex rigid foot deformities of ten consecutive patients treated with Smart Correction fixator system® from 2016 to 2020. Primary outcomes were classified as good, fair, and poor according to previously determined criteria. The outcomes were also assessed with The Manchester-Oxford Foot Questionnaire (MOXFQ). Non-parametric analysis (Wilcoxon test) for continuous variables and the Fisher's exact test for categorical variables were used. RESULTS: Plantigrade foot was achieved in all patients after correction program. Supramalleolar osteotomy was applied in nine feet, midfoot osteotomy was applied in two feet, hindfoot osteotomy was required in one foot, and only soft tissue distraction performed in two feet. Two patients had recurrent deformity managed by further acute corrections. The mean MOXFQ scores improved from 72.7 preoperatively to 24.8 at last follow-up. CONCLUSIONS: Present study shows that SCF the reliable option for the treatment of complex foot deformities, which also facilitates three-plane correction and concomitant lengthening with gradual soft tissue balance.

Developmental Foot Deformities in Patients with Connective Tissue Disorders.

¼: Foot deformities make up a large percentage of all orthopaedic complaints in patients with Down syndrome, Marfan syndrome, Ehlers-Danlos syndrome, Larsen syndrome, and osteogenesis imperfecta. ¼: Some common causes of foot deformities in these conditions include increased ligament laxity, hypotonia, and hypermobility of the joints. ¼: Treatment options for syndromic foot deformities include the use of foot orthoses, physical therapy, bracing, and various surgical procedures. ¼: There is limited evidence supporting the use of surgical intervention to correct foot deformities associated with Down syndrome, Marfan syndrome, Ehlers-Danlos syndrome, Larsen syndrome, and osteogenesis imperfecta. Therefore, further research is needed to determine the short-term and long-term outcomes of these procedures.

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.

Epidemiology and treatment outcomes in pediatric patients with post-injection paralysis.

BACKGROUND: Post-injection paralysis (PIP) of the sciatic nerve is an iatrogenic paralysis that occurs after an intramuscular injection, with resultant foot deformity and disability. This study investigates the epidemiology and treatment of PIP in Uganda. METHODS: Health records of pediatric patients surgically treated for PIP at the CoRSU Rehabilitation Hospital from 2013 to 2018 were retrospectively reviewed. Pre-operative demographics, perioperative management, and outcomes were coded and analyzed with descriptive statistics, chi-square for categorical variables, and linear models for continuous variables. RESULTS: Four-hundred and two pediatric patients underwent 491 total procedures. Eighty-three percent of reported injection indications were for febrile illness. Twenty-five percent of reported injections explicitly identified quinine as the agent. Although ten different procedures were performed, achilles tendon lengthening, triple arthrodesis, tibialis posterior and anterior tendon transfers composed 83% of all conducted surgeries. Amongst five different foot deformities, equinus and varus were most likely to undergo soft tissue and bony procedures, respectively (p=0.0223). Ninteen percent of patients received two or more surgeries. Sixty-seven percent of patients achieved a plantigrade outcome; 13.61% had not by the end of the study period; 19.3% had unreported outcomes. Those who lived further from the facility had longer times between the inciting injection and initial hospital presentation (p=0.0216) and were more likely to be lost to follow-up (p=0.0042). CONCLUSION: PIP is a serious iatrogenic disability. Prevention strategies are imperative, as over 400 children required 491 total surgical procedures within just six years at one hospital in Uganda.

Managing Complications of Foot and Ankle Surgery: Reconstruction of the Progressive Collapsing Foot Deformity.

Our understanding of the cause and principles of treatment of progressive collapsing foot deformity (PCFD) has significantly evolved in recent decades. The goals of treatment remain improvement in symptoms, correction of deformity, maintenance of joint motion, and return of function. Although notable advancements in understanding the deformity have been made, complications still occur and typically result from (1) poor decision making, (2) technical errors, and (3) patient-related conditions. In this article, we discuss common surgical modalities used in the treatment of PCFD and further highlight the common complications that occur and the techniques that can be used to prevent them.

Supramalleolar Lateral Opening-Wedge Osteotomy in Conjunction With Progressive Collapsing Foot Deformity Reconstruction for PCFD With Ankle Instability.

BACKGROUND: Reconstruction of progressive collapsing foot deformity (PCFD) with ankle instability (PCFD class E) remains a substantial challenge to orthopaedic surgeons. We report the outcomes of PCFD class E treated by means of a relatively standard PCFD foot reconstruction approach with the addition of a supramalleolar lateral opening-wedge osteotomy. METHODS: We conducted a retrospective study of 13 patients (15 ankles) who underwent this procedure for PCFD class E between 2010 and 2021. Mean follow-up time was 3.8 (range, 2-6.3) years. Clinical assessment was based on the Japanese Society for Surgery of the Foot (JSSF) ankle/hindfoot scale as well as a Self-Administered Foot Evaluation Questionnaire (SAFE-Q). Radiographic assessments, including identification of the mechanical ankle joint axis point and a modified valgus Takakura-Tanaka osteoarthritis grade, were recorded. RESULTS: The mean JSSF score improved significantly from 45.2 preoperatively to 83.9 postoperatively (P < .001). SAFE-Q scores at the final follow-up were 70.1 for the pain and pain-related subscale, 75.4 for the physical functioning and daily living subscale, 83.0 for the social functioning subscale, 74.4 for the shoe-related subscale, and 78.1 for the general health and well-being subscale. Radiographic measurements showed improvement in the tibiotalar tilt angle (average improvement: 5.4 degrees); orientation of the talus joint line relative to the ground (average improvement: 14.0 degrees); anteroposterior talus-first metatarsal angle (average improvement: 11.2 degrees), talonavicular coverage angle (average improvement: 21.6 degrees), and lateral talus-first metatarsal angle (average improvement: 17.0 degrees). Postoperatively, the mechanical ankle joint axis point moved medially for all patients and into the medial half of the ankle joint for 7 patients. The modified osteoarthritis stage improved postoperatively in most cases. CONCLUSION: In this select and relatively small group of patients who had a supramalleolar lateral opening-wedge osteotomy combined with PCFD reconstruction, we measured general improvement in JSSF scores and radiographic variables. Long-term durability of the procedure remains unknown. This procedure may be an option for preserving the ankle joint in treatment of PCFD class E with osteoarthritis of the ankle. LEVEL OF EVIDENCE: Level IV, therapeutic.

Diagnostic Accuracy of the Progressive Collapsing Foot Deformity (PCFD) Classification.

BACKGROUND: A consensus group recently proposed the term progressive collapsing foot deformity (PCFD) and a new classification with 2 stages plus 5 classes to describe the complex array of flatfoot deformities. This study aimed to validate different diagnostic accuracy rates of the PCFD classification. METHODS: This was a survey-based study distributed among 13 foot and ankle fellowship programs for 3 groups of participants with varied experience in practice (group 1: fellows in training, group 2: surgeons in practice for 1-4 years, and group 3: surgeons in practice for ≥5 years). Each participant was asked to assign 20 different cases of flatfoot deformity to the appropriate classes and stages using the PCFD classification. The overall diagnostic accuracy, class, and stage diagnostic accuracy rates for the 20 cases were calculated first for the entire cohort and then compared among the 3 groups. The misdiagnosis rate for each class of deformity (the sum of overdiagnosis and underdiagnosis rates) of the entire cohort was calculated and compared with the other classes. Mean and standard evidence were used to describe numerical data. One-way analysis of variance was used to compare values among the 3 groups and the 5 classes. P <.05 was considered statistically significant. RESULTS: For the whole cohort, the overall diagnostic accuracy, class diagnostic accuracy, and stage diagnostic accuracy rates were 71.0%, 78.3%, and 81.7%, respectively There was a statistically significant difference between group 1 and 2, and group 1 and 3, in overall diagnostic accuracy and class diagnostic accuracy, with no significant difference among the 3 groups regarding stage diagnostic accuracy. Class B had a significantly higher overdiagnosis rate than the rest of the classes, whereas class D was significantly underdiagnosed than others. The misdiagnosis rates for classes A to E were 3.3%, 17.5%, 11.1%, 26.0%, and 3.7%, respectively. CONCLUSION: The PCFD classification showed overall fair diagnostic accuracy rates. The highest diagnostic accuracy was for "hindfoot valgus deformity" and "ankle instability." Further content validation of the PCFD classification is needed to examine the terminology and interpretation of those classes with low diagnostic accuracy including "midfoot/forefoot abduction deformity," "forefoot varus deformity/medial column instability," and "peritalar subluxation/dislocation."Level of Evidence: Level II, prospective comparative study.

Flexor tenodesis procedure in the treatment of lesser toe deformities.

In this technical report study, we describe the use of a flexor tenodesis procedure in the treatment of lesser toe deformities (LTD). Using a specific implant, both the flexor digitorum longus and brevis tendons are attached to the plantar aspect of the proximal phalanx, allowing dynamic correction of flexible deformities of metatarsophalangeal and interphalangeal joints. Good clinical results and absence of complications were observed in a series of 3 patients, with considerable correction of the LTD, and absence of substantial residual floating toe or metatarsophalangeal joint stiffness. LEVEL OF EVIDENCE: V - Technical Report/Case Report/Expert Opinion.

Biomechanical Effects of Graft Shape for the Evans Lateral Column Lengthening Procedure: A Patient-Specific Finite Element Investigation.

BACKGROUND: The Evans calcaneal lengthening osteotomy procedure is widely used for correcting progressive collapsing foot deformity. However, it can result in overcorrection and degenerations of the calcaneocuboid joint. Different shapes of graft have been used in the Evans calcaneal osteotomy, but potential differences in their biomechanical effects is still unclear. The present study was designed to explore the biomechanical effects of graft shape and improve the Evans procedure to avoid or minimize detrimental effects. METHODS: Twelve patient-specific finite element models were established and validated. A triangular or rectangular wedge of varying size was inserted at the lateral edge of calcaneus, and the degree of correction was quantified. The stress in spring ligaments and plantar fascia and the contact characteristics of the talonavicular and calcaneocuboid joints were calculated and compared accordingly. RESULTS: The rectangular graft provided a much higher degree of correction than triangular grafts did. However, the contact characteristics of the calcaneocuboid joint and talonavicular joint were abnormal, with clear sensitivity to increased graft size, and the modeled strain of the spring ligament increased. CONCLUSION: The finite element analysis predicts that the rectangular grafts provide a higher degree of correction, but risks overcorrection compared with triangular grafts. The triangular graft may have a lower degree of disturbance to the biomechanical behaviors of the midtarsal joint. CLINICAL RELEVANCE: The model shows that both the shape and size of an Evans osteotomy bone wedge can have effects on the contiguous joints and ligamentous structures. Those effects should be considered when selecting a bone wedge for an Evans calcaneal osteotomy. LEVEL OF EVIDENCE: Level III, case-control study.