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.

Morphological changes in flatfoot: a 3D analysis using weight-bearing CT scans.

BACKGROUND: Flatfoot is a condition resulting from complex three-dimensional (3D) morphological changes. Most Previous studies have been constrained by using two-dimensional radiographs and non-weight-bearing conditions. The deformity in flatfoot is associated with the 3D morphology of the bone. These morphological changes affect the force line conduction of the hindfoot/midfoot/forefoot, leading to further morphological alterations. Given that a two-dimensional plane axis overlooks the 3D structural information, it is essential to measure the 3D model of the entire foot in conjunction with the definition under the standing position. This study aims to analyze the morphological changes in flatfoot using 3D measurements from weight-bearing CT (WBCT). METHOD: In this retrospective comparative our CT database was searched between 4-2021 and 3-2022. Following inclusion criteria were used: Patients were required to exhibit clinical symptoms suggestive of flatfoot, including painful swelling of the medial plantar area or abnormal gait, corroborated by clinical examination and confirmatory radiological findings on CT or MRI. Healthy participants were required to be free of any foot diseases or conditions affecting lower limb movement. After applying the exclusion criteria (Flatfoot with other foot diseases), CT scans (mean age = 20.9375, SD = 16.1) confirmed eligible for further analysis. The distance, angle in sagittal/transverse/coronal planes, and volume of the two groups were compared on reconstructed 3D models using the t-test. Logistic regression was used to identify flatfoot risk factors, which were then analyzed using receiver operating characteristic curves and nomogram. RESULT: The flatfoot group exhibited significantly lower values for calcaneofibular distance (p = 0.001), sagittal and transverse calcaneal inclination angle (p < 0.001), medial column height (p < 0.001), sagittal talonavicular coverage angle (p < 0.001), and sagittal (p < 0.001) and transverse (p = 0.015) Hibb angle. In contrast, the sagittal lateral talocalcaneal angle (p = 0.013), sagittal (p < 0.001) and transverse (p = 0.004) talocalcaneal angle, transverse talonavicular coverage angle (p < 0.001), coronal Hibb angle (p < 0.001), and sagittal (p < 0.001) and transverse (p = 0.001) Meary's angle were significantly higher in the flatfoot group. The sagittal Hibb angle (B = - 0.379, OR = 0.684) and medial column height (B = - 0.990, OR = 0.372) were identified as significant risk factors for acquiring a flatfoot. CONCLUSION: The findings validate the 3D spatial position alterations in flatfoot. These include the abduction of the forefoot and prolapse of the first metatarsal proximal, the arch collapsed, subluxation of the talonavicular joint in the midfoot, adduction and valgus of the calcaneus, adduction and plantar ward movement of the talus in the hindfoot, along with the first metatarsal's abduction and dorsiflexion in the forefoot.

Méary's angle decoded: 3D analysis of first ray plantarflexion deformity in Charcot-marie-tooth disease.

BACKGROUND: The typical cavovarus deformity seen in patients with Charcot-Marie-Tooth (CMT) involves plantarflexion of the first ray. The exact apex of the deformity has never been proven, although it is presumed to be within the medial cuneiform. The aim of this study was to utilize weight-bearing computed tomography (WBCT) to localize and quantify first ray plantarflexion deformity in CMT patients. METHODS: WBCTs of 16 CMT patients with lateral Méary's angle > 20 degrees were compared to controls utilizing semi-automated analysis software. A local coordinate system based on the first metatarsal was used to avoid bias of proximal deformity. The tarsometatarsal angle was subdivided into components (cuneiform-cuneiform joint normal, tarsometatarsal joint and metatarsal-metatarsal joint normal) and compared between CMT and controls. CMT patient's first, second and third rays were also compared. Means were compared with a 2-sample t test (p < .05). RESULTS: CMT patients had significantly more plantarflexion of the first ray than controls (16.4 versus 8.8 degrees respectively(p < 0.001)). The largest difference of was found at the medial cuneiform with 20.6 degrees of plantarflexion in CMT patients versus 14.8 degrees in controls (p < .0001). There was also approximately 2 degrees of plantarflexion at the TMT joint (p < .001). CONCLUSIONS: Plantarflexion deformity in CMT patients is primarily an osseous deformity at the level of the medial cuneiform with a lesser contribution from the tarsometatarsal joint. LEVEL OF EVIDENCE: III Retrospective comparative study.

Development and validation of a fully automated tool to quantify 3D foot and ankle alignment using weight-bearing CT.

INTRODUCTION: Foot and ankle alignment plays a pivotal role in human gait and posture. Traditional assessment methods, relying on 2D standing radiographs, present limitations in capturing the dynamic 3D nature of foot alignment during weight-bearing and are prone to observer error. This study aims to integrate weight-bearing CT (WBCT) imaging and advanced deep learning (DL) techniques to automate and enhance quantification of the 3D foot and ankle alignment. METHODS: Thirty-two patients who underwent a WBCT of the foot and ankle were retrospectively included. After training and validation of a 3D nnU-Net model on 45 cases to automate the segmentation into bony models, 35 clinically relevant 3D measurements were automatically computed using a custom-made tool. Automated measurements were assessed for accuracy against manual measurements, while the latter were analyzed for inter-observer reliability. RESULTS: DL-segmentation results showed a mean dice coefficient of 0.95 and mean Hausdorff distance of 1.41 mm. A good to excellent reliability and mean prediction error of under 2 degrees was found for all angles except the talonavicular coverage angle and distal metatarsal articular angle. CONCLUSION: In summary, this study introduces a fully automated framework for quantifying foot and ankle alignment, showcasing reliability comparable to current clinical practice measurements. This operator-friendly and time-efficient tool holds promise for implementation in clinical settings, benefiting both radiologists and surgeons. Future studies are encouraged to assess the tool's impact on streamlining image assessment workflows in a clinical environment.

Accuracy of Volumetric Bone Mineral Density Measurement in Weight Bearing, Cone Beam Computed Tomography.

BACKGROUND: Weight bearing computed tomography (WBCT) utilizes cone beam CT technology to provide assessments of lower limb joint structures while they are functionally loaded. Grey-scale values indicative of X-ray attenuation that are output from cone beam CT are challenging to calibrate, and their use for bone mineral density (BMD) measurement remains debatable. To determine whether WBCT can be reliably used for cortical and trabecular BMD assessment, we sought to establish the accuracy of BMD measurements at the knee using modern WBCT by comparing them to measurements from conventional CT. METHODS: A hydroxyapatite phantom with three inserts of varying densities was used to systematically quantify signal uniformity and BMD accuracy across the acquisition volume. We evaluated BMD in vivo (n = 5, female) using synchronous and asynchronous calibration techniques in WBCT and CT. To account for variation in attenuation along the height (z-axis) of acquisition volumes, we tested a height-dependent calibration approach for both WBCT and CT images. RESULTS: Phantom BMD measurement error in WBCT was as high as 15.3% and consistently larger than CT (up to 5.6%). Phantom BMD measures made under synchronous conditions in WBCT improved measurement accuracy by up to 3% but introduced more variability in measured BMD. We found strong correlations (R = 0.96) as well as wide limits of agreement (-324 mgHA/cm3 to 183 mgHA/cm3) from Bland-Altman analysis between WBCT and CT measures in vivo that were not improved by height-dependent calibration. CONCLUSION: Whilst BMD accuracy from WBCT was found to be dependent on apparent density, accuracy was independent of the calibration technique (synchronous or asynchronous) and the location of the measurement site within the field of view. Overall, we found strong correlations between BMD measures from WBCT and CT and in vivo measures to be more accurate in trabecular bone regions. Importantly, WBCT can be used to distinguish between anatomically relevant differences in BMD, however future work is necessary to determine the repeatability and sensitivity of BMD measures in WBCT.

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.

A statistical analysis of human talar shape and bone density distribution.

The shape of the talus, its internal structure, and its mechanical properties are important in determining talar behavior during loading, which may be significant for the design of surgical tools and implants. Although recent studies using statistical shape modeling have described quantitative talar external shape variation, no similar quantitative study exists to describe the density distribution of internal talar structure. The goal of this study is to quantify statistical variation in talar shape and density to benefit the design of talar implants. To this end, weight-bearing computed tomography (CT) scans of the ankle were collected in neutral, bilateral standing posture, and three-dimensional models were generated for each talus. Local density derived from the Hounsfield unit of each CT voxel was extracted. A weighted spherical harmonic analysis was performed to quantify the talar external shape. One hundred and seventy-nine volumes of interest were placed in the same relative position within each talus to quantify the talar density. Additionally, a finite element analysis (FEA) was conducted on a talus with both heterogeneous and homogeneous material properties to observe the effect of these properties on the stress and strain response. Significant differences were found in the talar density in sex and age, as well as in the stress and strain response between homogeneous and heterogeneous FEA. These differences show the importance of considering heterogeneity when examining the load response of tarsal bones.

Automatic software-based 3D-angular measurement for weight-bearing CT (WBCT) is valid.

BACKGROUND: The purpose of this study was to compare automatic software-based angular measurement (AM) with validated measurement by hand (MBH) regarding angle values and time spent for Weight-Bearing CT (WBCT) generated datasets. METHODS: Five-hundred WBCT scans from different pathologies were included in the study. 1st - 2nd intermetatarsal angle, talo-1st metatarsal angle dorsoplantar and lateral, hindfoot angle, calcaneal pitch angle were measured and compared between MBH and AM. RESULTS: The pathologies were ankle osteoarthritis/instability, n = 147 (29%); Haglund deformity/Achillodynia, n = 41 (8%); forefoot deformity, n = 108 (22%); Hallux rigidus, n = 37 (7%); flatfoot, n = 35 (7%); cavus foot, n = 10 (2%); osteoarthritis except ankle, n = 82 (16%). The angles did not differ between MBH and AM (each p > 0.36). The time spent for MBH / AM was 44.5 / 1 s on average per angle (p < .001). CONCLUSIONS: AM provided angles which were not different from validated MBH and can be considered as a validated angle measurement method. The time spent was 97% lower for AM than for MBH. LEVELS OF EVIDENCE: Level III.

Assessment of lower limb alignment: supine weight-bearing CT scanograms compared with a standing full-length radiograph.

PURPOSE: We identified limb misalignment by applying personalized axial force while the limb was in a supine position to mimic a standing posture. This study aimed to confirm the accuracy of evaluating lower limb alignment using supine weight-bearing CT scanograms. METHODS: We prospectively compared measurements of the weight-bearing line ratio (WBL), hip-knee-ankle (HKA) angle, and joint convergence angle (JLCA) in 46 sets of supine weight-bearing CT scanograms with those obtained from full-length standing anteroposterior lower extremity radiographs. We achieved the weight-bearing CT scanograms by applying six different levels of axial force: zero, 1/5 of body weight, 2/5 of body weight, 3/5 of body weight, 4/5 of body weight, and full body weight. We assessed the impact of age, body mass index, HKA, and JLCA on the observed mechanical axis deviation differences between the two methods. RESULT: The average absolute difference between standing radiographs and supine CT scanograms was 4.32% for the WBL ratio (p < 0.05), 1.25° for HKA (p < 0.05), and 0.46 for JLCA (p < 0.05). The mean absolute difference was minimal when applying full body weight axial pressure during CT scanograms (p > 0.05). Age, body mass index, HKA, and JLCA had no effect on the deviation in the mechanical axis measurements obtained through supine weight-bearing CT scanograms with full body weight. CONCLUSION: No significant differences were found in assessing lower limb alignment between standing radiographs and supine weight-bearing CT scanograms with full body weight. Weight-bearing CT scanograms prove to be a valuable method for assessing lower limb alignment while in a supine position.

The position, orientation, and relative size of the fibularis longus tubercle in normal patients: A weightbearing CT assessment.

The fibularis longus attaches to the base of the first metatarsal at the fibularis/peroneus longus tubercle (FLT/PLT). Theoretically, differences in FLT morphology may reflect changes in the function of the fibularis longus. This study defines the normal limits of the FLT position, orientation, and size in patients with morphologically normal foot anatomy. A retrospective analysis of 131 feet without deformity in 72 patients undergoing weightbearing CT (WBCT) at a single center was conducted. The position and morphology of the FLT was assessed with novel measurements including tubercle-floor distance, tubercle-metatarsal angle, and the angle between the floor and a line bisecting the FLT (bisecting angle). Roundness of the FLT was compared to a triangle limiting its shape (triangular ratio), with lower values indicating increasing roundness. We also report relative size of the FLT to the first metatarsal (X/Y ratio), and relative size of the first metatarsal and FLT to the second metatarsal (XY/Z ratio). There were no significant side to side differences for any measurement (p > 0.05). Mean values were: tubercle-floor distance 28.02 ± 2.63 mm, tubercle-metatarsal angle 32.7 ± 6.32 degrees, bisecting angle 65.58 ± 6.27 degrees, triangular ratio 0.69 ± 0.04, X/Y ratio 1.13 ± 0.20, and XY/Z ratio 3.44 ± -0.72. Bisecting angle strongly correlated with tubercle-metatarsal angle (Pearson correlation 0.840, p < 0.001) suggesting FLT rotation occurred independent of foot position. ICC was >0.943 for all measurements. This study reports the morphology of the FLT in individuals with normal feet. This normative data may be used in future studies examining differences between groups of patients with foot pathology, helping us better understand the role of fibularis longus in the development and treatment of foot disorders.

Assessment of knee instability in ACL-injured knees using weight-bearing computed tomography (WBCT): a novel protocol and preliminary results.

OBJECTIVE: To propose a protocol for assessing knee instability in ACL-injured knees using weight-bearing computed tomography (WBCT). MATERIALS AND METHODS: We enrolled five patients with unilateral chronic ACL tears referred for WBCT. Bilateral images were obtained in four positions: bilateral knee extension, bilateral knee flexion, single-leg stance with knee flexion and external rotation, and single-leg stance with knee flexion and internal rotation. The radiation dose, time for protocol acquisition, and patients' tolerance of the procedure were recorded. A blinded senior radiologist assessed image quality and measured the anterior tibial translation (ATT) and femorotibial rotation (FTR) angle in the ACL-deficient and contralateral healthy knee. RESULTS: All five patients were male, aged 23-30 years old. The protocol resulted in a 16.2 mGy radiation dose and a 15-min acquisition time. The procedure was well-tolerated, and patient positioning was uneventful, providing good-quality images. In all positions, the mean ATT and FTR were greater in ACL-deficient knees versus the healthy knee, with more pronounced differences observed in the bilateral knee flexion position. Mean lateral ATT in the flexion position was 9.1±2.8 cm in the ACL-injured knees versus 4.0±1.8 cm in non-injured knees, and mean FTR angle in the bilateral flexion position was 13.5°±7.7 and 8.6°±4.6 in the injured and non-injured knees, respectively. CONCLUSION: Our protocol quantitatively assesses knee instability with WBCT, measuring ATT and FTR in diverse knee positions. It employs reasonable radiation, is fast, well-tolerated, and yields high-quality images. Preliminary findings suggest ACL-deficient knees show elevated ATT and FTR, particularly in the 30° flexion position.

Altered Ulnar Variance With Full-Body Weight-bearing During Handstands With Upper Extremity Weight-bearing CT.

PURPOSE: Ulnar variance (UV) is a radiographic measurement relating the articular surface heights of the distal radius and ulna. Abnormal UV increases the risk for wrist pathology; however, it only provides a static measurement of an inherently dynamic bony relationship that changes with wrist position and loading. The purpose of this study was to investigate how full-body weight-bearing affects UV using weight-bearing computed tomography (WBCT). METHODS: Ten gymnasts completed two 45-second scans inside a WBCT machine while performing a handstand on a flat platform (H) and parallettes (P). A non-weight-bearing CT scan was collected to match clinical practice (N). Differences in UV between weight-bearing conditions were evaluated separately for dominant and nondominant sides, and then, UV was compared between weight-bearing conditions on pooled dominant/nondominant data. RESULTS: Pooled analyses comparing weight-bearing conditions revealed a significant increase in UV for H versus N (0.58 mm) and P versus N (1.00 mm), but no significant change in UV for H versus P (0.43 mm). Significant differences in UV were detected for H versus N, P versus N, and H versus P for dominant and nondominant extremities. The change from N to H was significantly greater in the dominant versus nondominant side, but greater in the nondominant side from N to P. CONCLUSIONS: Ulnar variance changed with the application of load and position of the wrist. Differences in UV were found between dominant and nondominant extremities. CLINICAL RELEVANCE: Upper extremity loading patterns are affected by hand dominance as defined by a cartwheel and suggest skeletal consequences from repetitive load on a dominantly used wrist. Although statistically significant, subtle changes detected in this investigational study do not necessarily bear clinical significance. Future WBCT research can lead to improved diagnostic measures for wrist pathologies affected by active loading and rotational wrist behavior.

Multiple factors contributing to the metatarsal head eversion in hallux valgus deformity. A prospective study using weight-bearing CT.

PURPOSE: Recently first tarsometatarsal arthrodesis for hallux abducto valgus (HAV) has been advocated as the sole procedure to correct the multiplanar components of the deformity. However, recent debate suggests other factors such as rearfoot pronation and metatarsal torsion affect frontal plane metatarsal eversion and sesamoid positioning. Using weight-bearing CT, 12 feet (12 subjects) with HAV deformities were placed in positions of maximum rearfoot pronation and supination in order to study the effects on metatarsal eversion, sesamoid rotation/displacement, and secondarily the influence of first metatarsal torsion. Sesamoid displacement was quantified by the novel use of the sesamoid displacement angle. PRINCIPLE RESULTS: Although first metatarsal eversion was nearly double in the pronated versus supinated foot, the difference was not statistically significant. Therefore, the bulk of first metatarsal eversion was not secondary to rearfoot eversion. Conversely, a significant positive correlation was found between metatarsal torsion and metatarsal head eversion angles in both supinated and pronated foot positions, with the strongest correlation with rearfoot pronation. Finally, significant increases in sesamoid displacement angles were noted with pronation. MAJOR CONCLUSIONS: The findings of the present study support the contention that multiple factors are associated with frontal plane first metatarsal eversion and sesamoid displacement. Weight-bearing CT scanning can be used to effectively evaluate the frontal plane components in HAV deformities. The sesamoid displacement angle appears to be a useful adjunct to evaluating the hallucal sesamoids. For surgical correction of the deformity, consideration should be given to pre-operative weight-bearing CT evaluation of the foot. This can illuminate the effects of rearfoot/medial column pronation and the potential influence of metatarsal torsion on the frontal plane components of this triplane deformity. In this way the potential for post-operative HAV recurrence can be minimized.

Cavovarus Deformity: Why Weight-Bearing Computed Tomography Should Be a First-Line Imaging Modality.

Cavovarus foot is a complex three-dimensional deformity, which includes a wide range of clinical conditions from subtle deformities to disabling feet. In this article, the authors discuss the role of weight-bearing computed tomography, which might enable to avoid double imaging (radiographs + tomography) in patients for which a detailed osteoarticular assessment is required, with the advantage to obtain tomographic images in standing position and a reduction of radiation exposure.

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.

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.

Effect of total ankle replacement on the 3-dimensional subtalar joint alignment in varus ankle osteoarthritis.

BACKGROUND: Varus ankle osteoarthritis (OA) is typically associated with peritalar instability, which may result in altered subtalar joint position. This study aimed to determine the extent to which total ankle replacement (TAR) in varus ankle OA can restore the subtalar alignment. METHODS: Fourteen patients (15 ankles, mean age 61 ± 6 years) who underwent TAR for varus ankle OA were analyzed using semi-automated measurements based on weight-bearing computed tomography. Twenty healthy individuals served as a control group. RESULTS: All angles improved between preoperative and a minimum of 1 year (mean 2.1 years) postoperative and were statistically significant in 6 out of 8 angles (P < 0.05). CONCLUSIONS: Our findings indicate that talus repositioning after TAR restores the subtalar joint alignment which may improve hindfoot biomechanics. Future studies are required to implement these findings for TAR in presence of hindfoot deformity. LEVEL OF EVIDENCE: IV.

Reliability and correlation of weight-bearing cone beam CT and Foot Posture Index (FPI) for measurements of foot posture: a test-retest study.

OBJECTIVE: To assess test-retest reliability and correlation of weight-bearing (WB) and non-weight-bearing (NWB) cone beam CT (CBCT) foot measurements and Foot Posture Index (FPI) MATERIALS AND METHODS: Twenty healthy participants (age 43.11±11.36, 15 males, 5 females) were CBCT-scanned in February 2019 on two separate days on one foot in both WB and NWB positions. Three radiology observers measured the navicular bone position. Plantar (ΔNAVplantar) and medial navicular displacements (ΔNAVmedial) were calculated as a measure of foot posture changes under loading. FPI was assessed by two rheumatologists on the same two days. FPI is a clinical measurement of foot posture with 3 rearfoot and 3 midfoot/forefoot scores. Test-retest reproducibility was determined for all measurements. CBCT was correlated to FPI total and subscores. RESULTS: Intra- and interobserver reliabilities for navicular position and FPI were excellent (intraclass correlation coefficient (ICC) .875-.997). In particular, intraobserver (ICC .0.967-1.000) and interobserver reliabilities (ICC .946-.997) were found for CBCT navicular height and medial position. Interobserver reliability of ΔNAVplantar was excellent (ICC .926 (.812; .971); MDC 2.22), whereas the ΔNAVmedial was fair-good (ICC .452 (.385; .783); MDC 2.42 mm). Using all observers' measurements, we could calculate mean ΔNAVplantar (4.25±2.08 mm) and ΔNAVmedial (1.55±0.83 mm). We demonstrated a small day-day difference in ΔNAVplantar (0.64 ±1.13mm; p<.05), but not for ΔNAVmedial (0.04 ±1.13mm; p=n.s.). Correlation of WBCT (WB navicular height - ΔNAVmedial) with total clinical FPI scores and FPI subscores, respectively, showed high correlation (ρ: -.706; ρ: -.721). CONCLUSION: CBCT and FPI are reliable measurements of foot posture, with a high correlation between the two measurements.

Can Weight-Bearing Computed Tomography Be a Game-Changer in the Assessment of Ankle Sprain and Ankle Instability?

Ankle sprain and chronic lateral ankle instability are complex conditions and challenging to treat. Cone beam weight-bearing computed tomography is an innovative imaging modality that has gained popularity, with a body of literature reporting reduced radiation exposure and operating time, and shortened examination time and a decreased time interval between injury and diagnosis. In this article, we make clearer the advantages of this technology and encourage researchers to investigate the area, and clinicians to use it as a primary mode of investigation. We also present clinical cases provided by the authors to illustrate those possibilities using advanced imaging tools.

The efficacy of flexor tenotomy to prevent recurrent diabetic foot ulcers (DIAFLEX trial): Study protocol for a randomized controlled trial.

Foot ulcers are a frequent and costly problem in people with diabetes mellitus and can lead to amputations. Prevention of these ulcers is therefore of paramount importance. Claw/hammer toe deformities are commonly seen in people with diabetes. These deformities increase the risk of ulcer development specifically at the (tip of) the toe. Percutaneous needle tenotomy of the tendon of the m. flexor digitorum longus (tendon tenotomy) can be used to reduce the severity of claw/hammer toe deformity with the goal to prevent ulcer recurrence. The main objective of this randomized controlled trial is to assess the efficacy of flexor tenotomy to prevent recurrence of toe ulcers in people with diabetes and a history of toe (pre-)ulcers. Additionally, we aim to assess interphalangeal joints (IPJ) and metatarsophalangeal joint (MTPJ) angles in a weight-bearing and non-weight-bearing position, barefoot plantar pressure during walking, cost-effectiveness and quality of life before and after the intervention and compare intervention and control study groups. Sixty-six subjects with diabetes and claw/hammer toe deformity and a recent history of (pre-)ulceration on the tip of the toe will be included and randomized between flexor tenotomy of claw/hammer toes (intervention) versus standard of care including orthosis and shoe offloading (controls) in a mono-center randomized controlled trial. Clinicaltrialsgov registration: NCT05228340.