The most responsive foot position for non-invasive detection of isolated unstable syndesmotic injuries - a 3D analysis.

BACKGROUND: The aim of this study was to identify the most responsive foot position for detection of isolated unstable syndesmotic injury. METHODS: Fourteen paired human cadaveric lower legs were positioned in a pressure-controlled radiolucent frame and loaded under 700 N. Computed tomography scans were performed in neutral position, 15° internal / external rotation, and 20° dorsal / plantar flexion of the foot before and after cutting all syndesmotic ligaments. For each position, generated 3D models of the intact and injured distal tibiofibular joints were matched and analyzed by calculating three parameters: diastasis, anteroposterior displacement, and shortening of the fibula. RESULTS: Transection of syndesmotic ligaments resulted in significant posterior translation of the fibula (4.34°, SD 1.63°, p < 0.01) compared to uninjured state for external rotation, significant anterior translation (-2.08°, SD 1.65°, p < 0.01) for internal rotation, and significant posterior translation (1.32°, SD 1.16°, p = 0.01) for dorsiflexion. Furthermore, the syndesmotic injury led to significantly increased clear space (0.46 mm, SD 0.46 mm, p = 0.03) in external rotation of the foot. CONCLUSION: External rotation of the foot under loading seems to be the most responsive position for detection of isolated syndesmotic instability. Under external rotational stress, anteroposterior instability and increased clear space resulting from a complete isolated unstable syndesmotic lesion were most evident.

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.

The Emerging Role of Automation, Measurement Standardization, and Artificial Intelligence in Foot and Ankle Imaging: An Update.

In the past few years, advances in clinical imaging in the realm of foot and ankle have been consequential and game changing. Improvements in the hardware aspects, together with the development of computer-assisted interpretation and intervention tools, have led to a noticeable improvement in the quality of health care for foot and ankle patients. Focusing on the mainstay imaging tools, including radiographs, computed tomography scans, and ultrasound, in this review study, the authors explored the literature for reports on the new achievements in improving the quality, accuracy, accessibility, and affordability of clinical imaging in foot and ankle.

MRI of Pediatric Foot and Ankle Conditions.

The increase in competitive sports practice among children and lack of ionizing radiation have resulted in a higher demand for MRI examinations. MRI of the children skeleton has some particularities that can lead orthopedists, pediatricians, and radiologists to diagnostic errors. The foot and ankle have several bones with abundant radiolucent and high signal intensity cartilage in several ossification centers, apophysis and physis, that can make this interpretation even harder. The present revision aims to show, how to differentiate between normal developmental findings and anatomic variants from pathologic conditions, whether mechanical, inflammatory, infectious, or neoplastic.

Magnetic Resonance Neurography of the Foot and Ankle.

Peripheral neuropathies of the foot and ankle can be challenging to diagnose clinically due to concomitant traumatic and nontraumatic or degenerative orthopedic conditions. Although clinical history, physical examination, and electrodiagnostic testing comprised of nerve conduction velocities and electromyography are used primarily for the identification and classification of peripheral nerve disorders, MR neurography (MRN) can be used to visualize the peripheral nerves as well as the skeletal muscles of the foot and ankle for primary neurogenic pathology and skeletal muscle denervation effect. Proper knowledge of the anatomy and pathophysiology of peripheral nerves is important for an MRN interpretation.

High-resolution Ultrasound of the Foot and Ankle.

High-resolution ultrasound (US) can be used to assess soft tissue abnormalities in the foot and ankle. Compared to MRI, it has lower cost, is widely available, allows portability and dynamic assessment. US is an excellent method to evaluate foot and ankle tendon injuries, ligament tears, plantar fascia, peripheral nerves, and the different causes of metatarsalgia.

Serous Atrophy of Bone Marrow in the Feet Diagnosed via Magnetic Resonance Imaging: A Case Report.

Serous atrophy of bone marrow (SABM) is characterized by focal replacement of bone marrow elements with extracellular gelatinous substances. It has been associated with a wide range of chronic conditions, including anorexia nervosa, malignancy, chronic kidney disease, and certain chronic infections. Previous literature has reported the disorder as primarily diagnosed via bone marrow biopsy and occurring outside of the distal extremities. Herein we describe a case of SABM occurring in the feet diagnosed via magnetic resonance imaging (MRI), a phenomenon that is rarely reported. The patient is a 45-year-old woman with a history of end-stage renal disease, congestive heart failure, type 2 diabetes, and peripheral arterial disease who initially presented with nonhealing, bilateral foot ulcers. She subsequently underwent several podiatric medical surgeries due to persistent foot infections and poor wound healing. During her most recent hospitalization, MRIs of her feet were obtained, and findings of abnormal bone marrow signal were attributed to technical malfunction of the MRI coil or scanner. After troubleshooting sources of malfunction, a repeated MRI of the foot was obtained and again demonstrated the same bone marrow signal abnormalities; at this time, SABM was diagnosed. Knowledge of this condition can prevent the misinterpretation of SABM on MRI and prevent the waste of time and medical resources.

Deep learning-based automated angle measurement for flatfoot diagnosis in weight-bearing lateral radiographs.

This study aimed to develop and evaluate a deep learning-based system for the automatic measurement of angles (specifically, Meary's angle and calcaneal pitch) in weight-bearing lateral radiographs of the foot for flatfoot diagnosis. We utilized 3960 lateral radiographs, either from the left or right foot, sourced from a pool of 4000 patients to construct and evaluate a deep learning-based model. These radiographs were captured between June and November 2021, and patients who had undergone total ankle replacement surgery or ankle arthrodesis surgery were excluded. Various methods, including correlation analysis, Bland-Altman plots, and paired T-tests, were employed to assess the concordance between the angles automatically measured using the system and those assessed by clinical experts. The evaluation dataset comprised 150 weight-bearing radiographs from 150 patients. In all test cases, the angles automatically computed using the deep learning-based system were in good agreement with the reference standards (Meary's angle: Pearson correlation coefficient (PCC) = 0.964, intraclass correlation coefficient (ICC) = 0.963, concordance correlation coefficient (CCC) = 0.963, p-value = 0.632, mean absolute error (MAE) = 1.59°; calcaneal pitch: PCC = 0.988, ICC = 0.987, CCC = 0.987, p-value = 0.055, MAE = 0.63°). The average time required for angle measurement using only the CPU to execute the deep learning-based system was 11 ± 1 s. The deep learning-based automatic angle measurement system, a tool for diagnosing flatfoot, demonstrated comparable accuracy and reliability with the results obtained by medical professionals for patients without internal fixation devices.

A finite element model of human hindfoot and its application in supramalleolar osteotomy.

BACKGROUND: The majority of the ankle osteoarthritis cases are posttraumatic and affect younger patients with a longer projected life span. Hence, joint-preserving surgery, such as supramalleolar osteotomy becomes popular among young patients, especially those with asymmetric arthritis due to alignment deformities. However, there is a lack of biomechanical studies on postoperative evaluation of stress at ankle joints. We aimed to construct a verifiable finite element model of the human hindfoot, and to explore the effect of different osteotomy parameters on the treatment of varus ankle arthritis. METHODS: The bones of the hindfoot are reconstructed using normal CT tomography data from healthy volunteers, while the cartilages and ligaments are determined from the literature. The finite element calculation results are compared with the weight-bearing CT (WBCT) data to validate the model. By setting different model parameters, such as the osteotomy height (L) and the osteotomy distraction distance (h), the effects of different surgical parameters on the contact stress of the ankle joint surface are compared. FINDINGS: The alignment and the deformation of hindfoot bones as determined by the finite element analysis aligns closely with the data obtained from WBCT. The maximum contact stress of the ankle joint surface calculated by this model increases with the increase of the varus angle. The maximum contact stresses as a function of the L and h of the ankle joint surface are determined. INTERPRETATION: The relationship between surgical parameters and stress at the ankle joint in our study could further help guiding the planning of the supramalleolar osteotomy according to the varus/valgus alignment of the patients.

Foot involvement in psoriatic arthritis: Prevalence, clinical and radiological features.

BACKGROUND: The purpose of this study was to evaluate the prevalence of foot involvement in psoriatic arthritis and to describe its different clinical and radiological features. PATIENTS AND METHODS: We conducted a cross sectional study including 40 patients with psoriatic arthritis over a period of 12 months. Anamnesis, clinical examination of feet, podoscopic examination, X-rays of feet and heels, and ultrasound in B mode and power Doppler mode were done for each patient. RESULTS: Foot involvement was found in 95% of cases. It was symptomatic in 70% and inaugural of the disease in 20% of cases. The hindfoot and the forefoot were the sites most affected (77.5% and 47.5% respectively). The involvement of the midfoot was rarer (25%). Dactylitis was found in 17.5% and deformities of forefoot were found in 22.5% of cases. Antalgic gait was noted in 17.5% and static disorders of foot at podoscopic examination were identified in 35% of cases. Feet dermatological manifestations were found in 45% of cases. Diagnosis of different rheumatological manifestations was based on clinical findings and caracteristic radiological images on X-rays. We demonstrate he sensitivity of ultrasound in the detection and the diagnosis of different foot lesions including enthesitis, synovitis and tenosynovitis, dactylitis, bone erosions and psoriatic nail dystrophy.

Does foot shape really matter? Correlation of patient reported outcomes with radiographic assessment in progressive collapsing foot deformity reconstruction: A systematic review.

BACKGROUND: In progressive collapsing foot deformity (PCFD), the goal of surgery is to obtain a well-balanced plantigrade foot. It remains unclear if restoration of the alignment and subsequent improvement in radiological parameters is associated with improved patient-reported outcome measures (PROMs). The aim of the current systematic review was to investigate whether there is a correlation between radiographic assessment and PROMs in patients treated surgically for flexible PCFD. MATERIALS AND METHODS: The study was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. A comprehensive literature search was performed in Pubmed, EMBASE, Cochrane Central Register of Controlled Trails (CENTRAL), and KINAHL. We included all the studies reporting both PROMs and radiological outcomes in patients treated surgically for PCFD. The quality of the included studies was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal tool. RESULTS: Six retrospective studies were included. Radiological parameters related to forefoot plantarflexion were associated with statistically significant differences in postoperative PROMs. A neutral hindfoot and midfoot position was positively correlated with postoperative PROMs but a statistically significant difference could not be established in all studies. The medial arch height was positively correlated with PROMs, but in one study this was the case only in revision surgeries. CONCLUSION: The literature so far suggests restoration of the alignment may be associated with improved PROMs. Future prospective studies that investigate possible radiological and clinical correlations in PCFD surgery are needed. LEVEL OF EVIDENCE: III.

From jargon to clarity: Improving the readability of foot and ankle radiology reports with an artificial intelligence large language model.

BACKGROUND: The purpose of this study was to evaluate the efficacy of an Artificial Intelligence Large Language Model (AI-LLM) at improving the readability foot and ankle orthopedic radiology reports. METHODS: The radiology reports from 100 foot or ankle X-Rays, 100 computed tomography (CT) scans and 100 magnetic resonance imaging (MRI) scans were randomly sampled from the institution's database. The following prompt command was inserted into the AI-LLM: "Explain this radiology report to a patient in layman's terms in the second person: [Report Text]". The mean report length, Flesch reading ease score (FRES) and Flesch-Kincaid reading level (FKRL) were evaluated for both the original radiology report and the AI-LLM generated report. The accuracy of the information contained within the AI-LLM report was assessed via a 5-point Likert scale. Additionally, any "hallucinations" generated by the AI-LLM report were recorded. RESULTS: There was a statistically significant improvement in mean FRES scores in the AI-LLM generated X-Ray report (33.8 ± 6.8 to 72.7 ± 5.4), CT report (27.8 ± 4.6 to 67.5 ± 4.9) and MRI report (20.3 ± 7.2 to 66.9 ± 3.9), all p < 0.001. There was also a statistically significant improvement in mean FKRL scores in the AI-LLM generated X-Ray report (12.2 ± 1.1 to 8.5 ± 0.4), CT report (15.4 ± 2.0 to 8.4 ± 0.6) and MRI report (14.1 ± 1.6 to 8.5 ± 0.5), all p < 0.001. Superior FRES scores were observed in the AI-LLM generated X-Ray report compared to the AI-LLM generated CT report and MRI report, p < 0.001. The mean Likert score for the AI-LLM generated X-Ray report, CT report and MRI report was 4.0 ± 0.3, 3.9 ± 0.4, and 3.9 ± 0.4, respectively. The rate of hallucinations in the AI-LLM generated X-Ray report, CT report and MRI report was 4%, 7% and 6%, respectively. CONCLUSION: AI-LLM was an efficacious tool for improving the readability of foot and ankle radiological reports across multiple imaging modalities. Superior FRES scores together with superior Likert scores were observed in the X-Ray AI-LLM reports compared to the CT and MRI AI-LLM reports. This study demonstrates the potential use of AI-LLMs as a new patient-centric approach for enhancing patient understanding of their foot and ankle radiology reports. Jel Classifications: IV.

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.

Hallux Valgus Plantar Pressure Distribution Before and After Surgery.

Hallux valgus is a common foot deformity that may cause pain and functional limitation, and often requires surgical correction. Clinical and radiographic parameters are typically used to assess postoperative outcomes. Plantar pressure distribution systems represent an innovative additional tool to evaluate hallux functional outcome after surgery. A systematic review of the current literature was performed to assess evaluation systems used for plantar pressure analysis and differences before and after hallux valgus surgery, and a possible relationship between different surgical techniques and clinical and radiographic results. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used for this review. Initial search results yielded 40 studies. Two additional studies were found through cross-reference. Twenty-five studies were screened. A total of 10 articles were included in the review process. Two main plantar pressure analysis systems were identified. Hallux function restoration based on plantar pressure measurement did not always occur. No relevant relationships between plantar pressure distribution data and different surgical techniques were established. All patients achieved satisfactory clinical and radiographic outcomes, regardless of surgical techniques used; however, no clear relationships were observed between clinical and radiographic results and the change in foot plantar pressure patterns. The current literature on this topic showed several methodologic limitations. Therefore, it is not possible to provide sufficiently supported evidence-based data regarding plantar pressure distribution rebalance after surgery using current plantar pressure analysis systems. Further investigations are needed to fill these gaps in evidence.

Comparison of the plantar pressure distribution and mechanical alignment in patients with varus knee osteoarthritis following high tibial osteotomy.

PURPOSE: The changes in the lower limb alignment were vitally important after high tibial osteotomy (HTO). Therefore, the purpose of present study was to analyze the characteristics of plantar pressure distribution after HTO, and to investigate the effect of plantar pressure distribution on postoperative limb alignment. METHODS: Between May 2020 and April 2021, varus knee patients undergoing HTO were evaluated in the present study. The peak pressure of plantar regions, medial-lateral pressure ratio (MLPR), foot progression angle (FTA), anteroposterior COP (AP-COP), lateral symmetry of COP (LS-COP), and the radiographic parameters were evaluated preoperatively and at the final follow-up. Compared among the slight valgus (SV), moderate valgus (MV) and large valgus (LV) groups at the final follow-up, the peak pressure of HM, HC and M5 regions, and the MLPR were compared; the Knee Injury and Osteoarthritis Outcome Score4 (KOOS4) including four subscales, and the American of orthopedic foot and ankle society (AOFAS) were evaluated. RESULTS: The WBL%, HKA and TPI angle changed significantly after HTO (P < 0.001). The preoperative group exhibited a lower peak pressure in the HM region (P < 0.05) and higher peak pressure in the M5 region (P < 0.05); the pre- and postoperative groups exhibited a lower peak pressure in the HC region (P < 0.05); the rearfoot MLPR was significantly lower and LS-COP was significantly higher in the preoperative group (P = 0.017 in MLPR and 0.031 in LS-COP, respectively). Comparison among the SV, MV and LV groups, the SV group indicated a lower peak pressure in the HM region (P = 0.036), and a lower MLPR in the rearfoot (P = 0.033). The KOOS Sport/Re score in the MV and LV groups increased significantly compared with the SV group (P = 0.042). CONCLUSION: Plantar pressure distribution during the stance phase in patients with varus knee OA following HTO exhibited a more medialized rearfoot plantar pressure distribution pattern than that before surgery. Compared with the small valgus alignment, a moderate to large valgus alignment allows patients to walk with a more even medial and lateral plantar pressure distribution, which is more similar to healthy adults.

Simulated Weightbearing Fluoroscopy to Assess Intraoperative Hindfoot Alignment.

BACKGROUND: Intraoperative evaluation of hindfoot alignment is one of the factors that may affect outcomes for foot and ankle reconstructive surgery. The present study was performed to evaluate the effect of simulated weightbearing fluoroscopy on the intraoperative assessment of hindfoot alignment reconstruction. METHODS: The medical records of patients diagnosed with disorders of the foot and ankle with abnormal hindfoot alignment were retrospectively reviewed from November 2014 to November 2021. Hindfoot alignment view (HAV) fluoroscopy in the simulated weightbearing position and HAV radiographs were routinely recorded during and after surgery, respectively. The hindfoot alignment angle (HAA) and hindfoot alignment ratio (HAR) were measured on intraoperative and postoperative images, respectively. RESULTS: Seventy-two women and 82 men (155 ankles) with a mean age of 45.48 years were included in the present study. The intraobserver and interobserver reliabilities of the HAA and HAR measurements were satisfactory. The intraoperative and postoperative HAA was -0.7 ± 4.8 degrees and -0.2 ± 5.0 degrees, respectively. The mean HAR on intraoperative fluoroscopy and postoperative radiographs was 37.4% ± 19.7% and 40.4% ± 18.2%, respectively. Simple regression analysis revealed a correlation between the intraoperative and postoperative HAA (R2 = 0.631, P < .001) and HAR (R2 = 0.262, P < .001). Univariate analysis suggested that the difference between the intraoperative and postoperative HAA was positively affected by the body mass index (P < .001). CONCLUSION: The present study showed that intraoperative HAV fluoroscopy in the simulated weightbearing position is a potentially useful method to predict postoperative hindfoot alignment in the weightbearing position. Patients with a lower body mass index had smaller HAA deviations between intraoperative and postoperative measurements of hindfoot alignment. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Clinical, Radiographic and Gait Parameters Associated with Medial Arch Pain in the Flexible Pediatric Flatfoot.

Pain in the flexible flatfoot is a common complaint, if present it is important to find its exact location and causes Therefore, the study aimed to find differences between children with and without medial arch pain and relate them to the reduction of pain following surgical treatment. Children with idiopathic flexible flatfeet were retrospectively included in the study. All children underwent a clinical, radiographic, and gait examination. The feet were subdivided into 2 groups: asymptomatic and those with medial arch pain. Factors associated with medial arch pain were identified via t test. Significant radiological and gait parameters were correlated to the change in medial arch pain score following surgery. Included were 322 feet belonging to 177 children, with the mean age of 11.8 (SD = 2.2) years. The pain was perceived in 52% of the feet, of these, 74% in the medial arch. In the group with pain, 31 feet received a gait analysis following surgery. The radiological parameters, talus-1 and -2 metatarsal angles and the gait parameter, calcaneal lateral shift during walking showed a significant difference (p ≤ .004) between the no pain and pain groups and were associated (R2 ≥0.14, p ≤ .04) with the reduction in pain following surgery. The increased talus-1 and -2 metatarsal angles and the calcaneal lateral shift may cause increased tension on the soft-tissues along the medial side of the foot and may produce pain. Therapies aiming at improving the medial arch pain should be directed to normalize the talus-1 or -2 metatarsal angles and the calcaneal lateral shift.