Ankle and hindfoot motion of healthy adults during running revealed by dynamic biplane radiography: Side-to-side symmetry, sex-specific differences, and comparison with walking.

This study aimed to characterize ankle and hindfoot kinematics of healthy men and women during overground running using biplane radiography, and to compare these data to those previously obtained in the same cohort during overground walking. Participants ran across an elevated platform at a self-selected pace while synchronized biplane radiographs of their ankle and hindfoot were acquired. Motion of the tibia, talus, and calcaneus was tracked using a validated volumetric model-based tracking process. Tibiotalar and subtalar 6DOF kinematics were obtained. Absolute side-to-side differences in ROM and kinematics waveforms were calculated. Side-to-side and sex-specific differences were evaluated at 10 % increments of stance phase with mixed model analysis. Pearson correlation coefficients were used to assess the relationship between stance-phase running and walking kinematics. 20 participants comprised the study cohort (10 men, mean age 30.8 ± 6.3 years, mean BMI 24.1 ± 3.1). Average absolute side-to-side differences in running kinematics waveforms were 5.6°/2.0 mm or less at the tibiotalar joint and 5.2°/3.2 mm or less at the subtalar joint. No differences in running kinematics waveforms between sides or between men and women were detected. Correlations were stronger at the tibiotalar joint (42/66 [64 %] of correlations were p < 0.05), than at the tibiotalar joint (38/66 [58 %] of correlations were p < 0.05). These results provide a normative reference for evaluating native ankle and hindfoot kinematics which may be informative in surgical or rehabilitation contexts. Sex-specific differences in ankle kinematics during overground running are likely not clinically or etiologically significant. Associations seen between walking and running kinematics suggest one could be used to predict the other.

Ultrasound imaging and Fascial Manipulation®: 'Adding a twist' on the ankle retinacula.

BACKGROUND: Retinacula of the ankle are thickening of the deep fascia of the leg (crural fascia) and foot i.e. inseparable structures. Recent studies report their crucial role in functional stability and proprioception of the ankle. CASE PRESENTATION: A 38-yr-old Caucasian man - with a history of lateral malleolus fracture 12 years ago, obesity and right ankle osteoarthritis - was referred to a physiatrist for a right ankle pain that had significantly worsened over the last year. During walking, the patient experienced stinging pain in the area of tibialis anterior and peroneus tertius muscles, and the superior extensor retinaculum. Magnetic resonance imaging and ultrasonography showed clear thicknening (2.05 mm) of the oblique superomedial band of the inferior extensor retinaculum. Sonopalpation was performed to precisely evaluate/confirm the site of maximum pain. Foot function index (FFI) score was 42. RESULTS: Subsequently, the patient was prescribed fascial manipulation, and he had clinical improvement after the first session (FFI: 21). At 1-month follow-up, the patient was still asymptomatic without any functional limitation (FFI: 24). US imaging confirmed the decreased thickness of the oblique superomedial band of the extensor retinaculum (1.35 mm). CONCLUSION: Fascial Manipulation® appears to be a useful tool to reduce thickness, stiffness, and pain in this case as displayed by the ultrasound Imaging.

A New Paradigm in Foot and Ankle Outcomes?: Away From Radiographs and Toward Patient-Centered Outcomes.

Having reasonable outcome measures is essential to unbiased research. For years, provider-measured outcomes have been valued as they are more objective and convenient for investigators. However, with the popularity of patient-centered medical care delivery, patient-reported outcome measures are appropriately becoming more popular in foot and ankle research.

EURO-MUSCULUS/USPRM Dynamic Ultrasound Protocols for Ankle/Foot.

ABSTRACT: In this dynamic scanning protocol, ultrasound examination of the ankle is described using various maneuvers to assess different conditions. Real-time patient examination and scanning videos are used for better simulation of daily clinical practice. The protocol is prepared by several/international experts in the field of musculoskeletal ultrasound and within the umbrella of European Musculoskeletal Ultrasound Study Group in Physical and Rehabilitation Medicine/Ultrasound Study Group of the International Society of Physical and Rehabilitation Medicine.

The Use of the Lateral Tibial Line to Assess Ankle Alignment: A Preliminary Investigation.

BACKGROUND: Although the medial clear space (MCS) is commonly used to assess talar alignment and ankle stability, its measurement is variable with multiple reported normal values. We have observed that the lateral tibial shaft is a reliable landmark to assess talar alignment. The objective of the current investigation was to determine the normal relationship of the lateral tibia to the superolateral talus using a tangent drawn inferiorly from the lateral tibial shaft, which we refer to as the "lateral tibial line" (LTL). METHODS: The relationship of the LTL to the superolateral talus was assessed by three reviewers on 99 standing ankle mortise radiographs in uninjured patients. This relationship was quantified by measuring the distance (in millimeters) between the LTL and the superolateral talus. In addition, the interobserver reliability of the LTL measurement was recorded and compared with that of the MCS. RESULTS: The median value for the distance between the superolateral talus and LTL was -0.50 mm with an interquartile range of -1.4 to 0.0 mm. The LTL was within 1 mm of the lateral talus in 176 of 297 reviewer measurements (59.3%). Moreover, it was either lateral to or at most 1 mm medial to the lateral talus in 90.9% of cases. The LTL measurement also demonstrated good interobserver reliability (0.764, 95% confidence interval, 0.670 to 0.834), similar to the measurement of MCS (0.742, 95% confidence interval, 0.539 to 0.846). CONCLUSIONS: The relationship between the LTL and superolateral talus is easily measured with good reliability for assessing the anatomic relationship of the tibia and talus. The LTL uncommonly fell more than 1 mm medial to the superolateral talus, as might be seen with displaced ankle fractures. These findings will hopefully serve as a basis for future studies evaluating its role in assessing lateral displacement and stability of isolated fibula fractures. LEVEL OF EVIDENCE: Level III, retrospective review.

Prevalence of Ankle Charcot Neuroarthropathy Presenting in a Tertiary Care Center.

Charcot neuroarthropathy's (CN) anatomic classification was originally formulated by the Brodsky article and the Trepman et al modification, including midfoot (type 1), rearfoot (type 2), ankle (type 3a), calcaneus (type 3b), multiarticular (type 4), and forefoot (type 5). In these classic studies, ankle joint and multijoint CN are reported as 9% and 6% to 9%, respectively, but we believe ankle CN to be more common than that in a tertiary setting. We retrospectively reviewed patients presenting initially or as referral between 2004 and 2020. Initial presentation radiographs were reviewed and classified by 3 authors based on Brodsky's model with Trepman and colleagues' modification, and any discrepancies were reviewed by the fourth author. A total of 175 patients (205 feet) were assessed. This revealed 80 cases classified as type 1 (39.0%), 23 cases type 2 (11.2%), 17 cases type 3a (8.3%), 2 cases type 3b (1.0%), and 83 cases type 4 (40.5%). After subdividing type 4, total prevalence included 150 with type 1 anatomic location (73.2%), 103 type 2 (50.2%), 44 type 3a (21.5%), and still 2 type 3b (1.0%). This study revealed a similar prevalence of isolated ankle CN (8.5%) compared to the Trepman et al article (9%), however, in total, ankle CN (21.5%) occurred 2.4-times more than the original 9%. Our study also found there to be a higher prevalence of ankle CN in the setting of multiarticular CN, which has not been evaluated in past studies. The prevalence of multiarticular CN was found to be 4.5-fold greater than the Trepman article (6%-9%).

Diagnostic applications and benefits of weightbearing CT in the foot and ankle: A systematic review of clinical studies.

BACKGROUND: Foot and ankle weightbearing CT (WBCT) imaging has emerged over the past decade. However, a systematic review of diagnostic applications has not been conducted so far. METHOD: A systematic literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines after Prospective Register of Systematic Reviews (PROSPERO) registration. Studies analyzing diagnostic applications of WBCT were included. Main exclusion criteria were: cadaveric specimens and simulated WBCT. The Methodological Index for Non-Randomized Studies (MINORS) was used for quality assessment. RESULTS: A total of 78 studies were eligible for review. Diagnostic applications were identified in following anatomical area's: ankle (n = 14); hindfoot (n = 41); midfoot (n = 4); forefoot (n = 19). Diagnostic applications that could not be used on weightbearing radiographs (WBRX) were reported in 56/78 studies. The mean MINORS was 9.8/24 (range: 8-12). CONCLUSION: Diagnostic applications of WBCT were most frequent in the hindfoot, but other areas are on the rise. Post-processing of images was the main benefit compared to WBRX based on a moderate quality of the identified studies.

Male elite soccer players have a higher incidence of accessory ossicles in the foot and ankle.

PURPOSE: Accessory ossicles are caused by the failure of the fusion of secondary ossification centres and are more likely to occur due to heavy loading during the growth period or improper treatment after injury. This study aimed to investigate the incidence of foot and ankle accessory ossicles in male professional soccer players. METHODS: This study included male professional soccer players who underwent medical checkups at our hospital between 2017 and 2023 as the soccer group. Medical checkups included radiographs of bilateral anteroposterior and oblique foot, as well as bilateral anteroposterior and lateral ankle. Male patients age-matched with the soccer group who visited our hospital undergoing anteroposterior and oblique foot or anteroposterior and lateral ankle radiography were included in the control group. The incidence of accessory ossicles was investigated and compared between the soccer and control groups. RESULTS: In this study, 276 ankles and 276 feet, as well as 121 ankles and 79 feet, were included in the soccer and control groups, respectively. The incidence of accessory ossicles in the soccer and control groups was as follows: accessory navicular 35.9%, 24% (P = .049), os peroneum 8.0%, 2.5% (P = .09); os supranaviculare 7.6%, 1.3% (P = .039); os infranaviculare 1.4%, 1.3% (P = .090); os calcaneus secundarius 4.3%, 0% (P = .059); os vesalianum 0%, 0%; os subfiblare 12.7%, 2.5% (P < .001); os subtibiale 18.1%, 2.5% (P = .001); and os trigonum 89%, 24% (P < .001). CONCLUSIONS: Male professional soccer players had a higher incidence of accessory navicular, os supranaviculare, os subfiblare, os subtibiale, and os trigonum.

Morphological features of the non-affected side of the hindfoot in patients with unilateral varus ankle osteoarthritis.

BACKGROUND: The innate shape characteristics of the hindfoot bones alter the loading conditions of the foot and thus may be associated with an increased risk of developing varus ankle osteoarthritis (OA). This study aimed to clarify the innate morphological patterns of the hindfoot bones that may be associated with ankle OA by analyzing the differences between the bone morphology of the non-affected side of patients with unilateral varus ankle OA and that of healthy participants. METHODS: In this case-control study, computed tomography images were used to develop three-dimensional models of three hindfoot bones (distal tibia with fibula, talus, and calcaneus) from 23 non-affected sides of patients with radiography-diagnosed unilateral ankle OA and 22 healthy control participants. Anatomical and sliding landmarks were placed on the surface of each bone, and the principal components (PCs) of shape variation among specimens were independently calculated for each bone, preserving homology between individuals. The PC modes representing 5% or more of the overall variation were statistically compared between the ankle OA and control groups. RESULTS: Significant differences were identified between the OA and control groups in the fifth PC mode for the tibia with fibula (proportion of variance, 5.1%; p =.025), fifth PC mode for the talus (6.7%, p =.031), and third PC mode for the calcaneus (7.4%, p =.001). The hindfoot bones of the participants who developed ankle OA had the following innate morphological characteristics: the lateral malleolar articular surface of the fibula was shifted superiorly, tibial plafond was enlarged posteroinferiorly, posterior width of the talar trochlea was narrower, talonavicular articular surface of the talus was oriented more frontally, anterior-middle talocalcaneal articular surfaces of the talus were more medially shifted and those of the calcaneus were flatter, calcaneal sustentaculum tali was less protruding, and lateral plantar process of the calcaneus was more superiorly positioned. CONCLUSIONS: These distinctive morphological alterations may increase the incidence and progression of varus ankle OA through aberrant anterior translation, internal rotation, and varus tilting of the talus.

Anterior Tarsal Tunnel Syndrome: Entrapment of the Articular Branch of Deep Peroneal Nerve: A Case Report.

CASE: A 28-year-old male patient who injured his ankle 2 years ago presented with unilateral ankle pain, tingling, and numbness for 1 year. Clinically, tenderness and positive Tinel sign were localized on anterior aspect of ankle. On exploration, deep peroneal nerve and mainly its articular branch were encased in fibrotic tissue. Decompression of both nerves resulted in symptomatic relief after surgery. CONCLUSION: High index of suspicion, a thorough medical history, meticulous clinical examination, complete knowledge of nerve anatomy, proper radiological studies, and careful surgical decompression are all necessary for the diagnosis and management of such atypical cases.

Evaluation of arthrokinematics and posterior soft tissues of the ankle during ankle dorsiflexion using ultrasound.

BACKGROUND: Arthrokinematics (caudal and posterior movements of the talus) and posterior soft tissues of the ankle during ankle dorsiflexion have not been objectively evaluated in detail. This study aimed to investigate the characteristics of arthrokinematics and posterior soft tissues of the ankle during ankle dorsiflexion using ultrasound. METHODS: Thirteen healthy adults participated in the study. Participants whose passive dorsiflexion range of motion (ROM) of the ankle joint was <35° were classified as the restricted group (n = 6), and participants whose passive ankle dorsiflexion ROM was ≥35° were classified as the control group (n = 7). Passive ankle dorsiflexion was performed to measure the ankle arthrokinematics. Strain elastography was performed to measure the elasticity of the flexor hallucis longus (FHL) and Kager's fat pad (KFP) at each dorsiflexion angle. RESULTS: A significant difference in the posterior movement of the talus at the ankle dorsiflexion of 30° was observed between the two groups (P = 0.04). The elasticity of the restricted group was increased at all angles in both FHL and KFP (P < 0.05). CONCLUSION: This study showed that it is possible to objectively evaluate the direction of ankle arthrokinematics and posterior ankle soft-tissue restrictions using ultrasound.

Forensic age estimation with ankle MRI: Evaluating distal tibial and calcaneal epiphyseal fusion.

Forensic authorities often request age estimation from forensic experts, particularly in cases related to sexual abuse, child pornography, illegal migration, marriage, etc. The most commonly used method in this regard is radiological methods. Because of the potential dangers of radiation exposure outside of clinical indications, new researches are focusing on non-ionizing and non-invasive technologies. This study aimed to demonstrate the applicability of age estimation in living individuals from ankle magnetic resonance images as a non-ionizing method, and to determine whether it is compatible with individuals' real ages and to establish a database. Ankle MRI images of patients aged between 7 and 26 years who applied to the Cukurova University Faculty of Medicine Balcali Hospital between January 2011 and December 2020 were retrospectively evaluated. A six-stage staging method proposed by Lu et al. was applied to the distal tibial and calcaneal epiphyseal ossification points by examining ankle MRI images of a total of 331 patients, 197 males and 134 females. In the study, images obtained from a sagittal section fast spin echo T1-weighted sequence, with a section thickness of 3-4 mm, were evaluated. As a result of the study, Stage 1 in both distal tibial and calcaneal epiphysis was observed only in patients under 18 years of age in both sex. In males, stage 2 in distal tibial epiphyseal ossification was observed under 18 years of age, except for one case, and stage 5 in both distal tibial and calcaneal epiphyseal ossification was observed in almost all cases over 18 years of age in males. According to the results of our study, magnetic resonance imaging was found to be a non-ionizing method that could be used in addition to other radiological methods aimed at determining the 18-year age limit in age estimation. Multicenter, comparative, and prospective studies conducted by experienced researchers are needed to enable the routine use of MRI in age estimation.

Ankle Joint Bone Density Distribution Correlates with Overall 3-Dimensional Foot and Ankle Alignment.

BACKGROUND: Altered stress distribution in the lower limb may impact bone mineral density (BMD) in the ankle bones. The purpose of the present study was to evaluate the spatial distribution of BMD with use of weight-bearing cone-beam computed tomography (WBCT). Our hypothesis was that BMD distribution would be even in normal hindfeet, increased medially in varus hindfeet, and increased laterally in valgus hindfeet. METHODS: In this study, 27 normally aligned hindfeet were retrospectively compared with 27 valgus and 27 varus-aligned hindfeet. Age (p = 0.967), body mass index (p = 0.669), sex (p = 0.820), and side (p = 0.708) were similar in the 3 groups. Hindfoot alignment was quantified on the basis of WBCT data sets with use of multiple measurements. BMD was calculated with use of the mean Hounsfield unit (HU) value as a surrogate. The HU medial-to-lateral ratio (HUR), calculated from tibial and talar medial and lateral half-volumes, was the primary outcome of the study. RESULTS: The 3 groups significantly differed (p < 0.001) in terms of tibial HUR (median, 0.91 [interquartile range (IQR), 0.75 to 0.98] in valgus hindfeet, 1 [IQR, 0.94 to 1.05] in normal hindfeet, and 1.04 [IQR, 0.99 to 1.1] in varus hindfeet) and talar HUR (0.74 [IQR, 0.50 to 0.80] in valgus hindfeet, 0.82 [IQR, 0.76 to 0.87] in normal hindfeet, and 0.92 [IQR, 0.86 to 1.05] in varus hindfeet). Linear regression showed that all hindfoot measurements significantly correlated with tibial and talar HUR (p < 0.001 for all). The mean HU values for normally-aligned hindfeet were 495.2 ± 110 (medial tibia), 495.6 ± 108.1 (lateral tibia), 368.9 ± 80.3 (medial talus), 448.2 ± 90.6 (lateral talus), and 686.7 ± 120.4 (fibula). The mean HU value for each compartment was not significantly different across groups. CONCLUSIONS: Hindfoot alignment and medial-to-lateral BMD distribution were correlated. In varus hindfeet, an increased HU medial-to-lateral ratio was consistent with a greater medial bone density in the tibia and talus as compared with the lateral parts of these bones. In valgus hindfeet, a decreased ratio suggested greater bone density in the lateral as compared with the medial parts of both the tibia and the talus. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Artificial intelligence in foot and ankle surgery: current concepts.

The twenty-first century has proven that data are the new gold. Artificial intelligence (AI) driven technologies might potentially change the clinical practice in all medical specialities, including orthopedic surgery. AI has a broad spectrum of subcomponents, including machine learning, which consists of a subdivision called deep learning. AI has the potential to increase healthcare delivery, improve indications and interventions, and minimize errors. In orthopedic surgery. AI supports the surgeon in the evaluation of radiological images, training of surgical residents, and excellent performance of machine-assisted surgery. The AI algorithms improve the administrative and management processes of hospitals and clinics, electronic healthcare databases, monitoring the outcomes, and safety controls. AI models are being developed in nearly all orthopedic subspecialties, including arthroscopy, arthroplasty, tumor, spinal and pediatric surgery. The present study discusses current applications, limitations, and future prospective of AI in foot and ankle surgery.

Osteomyelitis and Septic Arthritis of the Foot and Ankle: Imaging Update.

Radiography is considered the first-line screening exam for clinically suspected osteomyelitis. However, additional evaluation is generally needed. MRI is the definitive diagnostic exam with high sensitivity and specificity combined with excellent anatomic definition. Gadolinium contrast can be useful to detect areas of devitalization before surgery. Bone marrow edema on fluid-sensitive images and low signal intensity on T1-weighted images in the presence of secondary MRI findings, including ulcer, sinus tract, and cellulitis with or without abscess are typical findings of osteomyelitis. If MRI is contraindicated, three phase bone scan can be used. Early diagnosis and treatment is essential.

Presurgical and Postsurgical MRI Evaluation of Osteochondral Lesions of the Foot and Ankle: A Primer.

The gold standard diagnostic imaging tool for ankle OCLs is magnetic resonance imaging, which allows precise evaluation of the articular cartilage and assessment of the surrounding soft tissue structures. Post-operative morphologic MRI assessment via MOCART scores provide semi-quantitative analysis of the repair tissue, but mixed evidence exists regarding its association with post-operative outcomes. Post-operative biochemical MRIs allow assessment of the collagen network of the articular cartilage via T2-mapping and T2∗ mapping, and assessment of the articular glycosaminoglycan content via delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T1rho mapping and sodium imaging.

Weight-Bearing Computed Tomography of the Foot and Ankle-What to Measure?

Weight-bearing computed tomography (WBCT) was introduced in 2012 for foot and ankle applications as a breakthrough technology that enables full weight-bearing, three-dimensional imaging unaffected by x-ray beam projections or foot orientation. The literature describing the use of WBCT in the treatment of foot and ankle disorders is growing, and this article provides an overview of what can be measured with WBCT.

Image-Guided Foot and Ankle Injections.

Ultrasound is a high-resolution, real-time imaging modality that is frequently used for image-guided procedures. Due to the highly complex anatomy of the foot and ankle, ultrasound should be considered a first-line imaging modality for injections and procedures in this region.