Multisegmented foot models (MSFMs) are used to capture data of specific regions of the foot instead of representing the foot as a single, rigid segment. It has been documented that different MSFMs do not yield the same joint kinematic data, but there is little information available regarding their use for kinetic analysis. We compared the moment and power at the tibiotalar, midtarsal, and metatarsophalangeal joints of four MSFMs using motion capture data of young adult runners during stance phase of barefoot walking and jogging. Of these models, three were previously validated: the Oxford, Milwaukee, and Ghent Foot Models. One model was developed based upon literature review of existing models: the \"Vogel\" model. We performed statistical parametric mapping comparing joint measurements from each model to the corresponding results from the Oxford model, the most heavily studied MSFM. We found that the Oxford, Milwaukee, Vogel, and Ghent Foot Models do not provide the same kinetic results. The differences in segment definitions impact the degrees of freedom in a manner that alters the measured kinematic function of the foot, which in turn impacts the kinetic results. The results of this study capture the variability in performance of MSFMs as it relates to kinetic outcomes and emphasize a need to remain aware of model differences when interpreting results.

The aim of the study was to measure and compare plantar pressures, forces and gait parameters in athletes with and without hallux valgus. It was a cross sectional study with the sample Size: 106 [53 for each group (Hallux valgus and without hallux valgus)]. Hallux valgus angle was calculated with digital photographs uploaded on Karasunpo software. Participants only with the moderate and severe hallux valgus angle were selected. For participant having hallux valgus in both the feet, one with the greater angle of hallux valgus was selected. Participants without hallux valgus were the ones whose hallux valgus angle was less than 15 degrees. The participants of both groups were asked to walk on predetermined speed of 4.8 kmph. The device used was Zebris FDM-T (Zebris® Medical GmbH, Germany) for the pedobarographic and gait parameter measurement. On an average, measurement was recorded for 20 steps during the different phases of gait in all subjects and corresponding mean values were calculated. Mean values for all the readings were documented and statistically calculated. Statistical analysis was done using SPSS (v.27.0.1) with unpaired t-test to compare between both the groups. Shapiro-Wilk test was used to check normality of data. Significant p-values for forefoot forces (0.001), forefoot pressures (<0.001) and midfoot pressures (0.002) were found. There is clear evidence of increased foot loading in young adult athletes with hallux valgus on the forefoot and midfoot regions while performing activities.

Lisfranc injuries are rare but severe injuries of the foot. They range from ligament sprain to complex fracture dislocations. Etiologically, a distinction is made between indirect and direct force and between high-energy and low-energy trauma. Inadequate diagnostics (injuries overlooked or misinterpreted) can lead to painful posttraumatic osteoarthritis, chronic instability and deformity of the foot. A fracture, malalignment and unclear findings in conventional radiological diagnostics necessitate computed tomography imaging including 3D reconstruction. Lisfranc injuries are often associated with accompanying pathologies of the foot that also need to be addressed. Only stable non-displaced fractures can be treated conservatively. Depending on the injury pattern, surgical treatment is performed percutaneously, minimally invasive or open. The prognosis following Lisfranc injury is determined by the severity of damage and the quality of reconstruction.
UNASSIGNED: Lisfranc-Gelenk-Verletzungen sind seltene, aber schwere Verletzungen des Fußes, die von Bandzerrungen bis zu komplexen Luxationsfrakturen reichen. Ätiologisch werden direkte und indirekte Gewalteinwirkung sowie Hoch- und Niedrigenergietrauma unterschieden. Eine inadäquate Diagnostik (Übersehen oder Fehlinterpretation von Verletzungen) kann zu schmerzhaften posttraumatischen Arthrosen, chronischen Instabilitäten und Fehlstellung des Fußskeletts führen. Ein Fraktur- oder Fehlstellungsnachweis und ein unklarer Befund in der konventionellen Röntgendiagnostik erfordern eine CT einschließlich 3D-Rekonstruktionen. Häufig finden sich pathologische Begleiterscheinungen des Fußes, die ebenfalls adressiert werden müssen. Ausschließlich stabile undislozierte Frakturen können konservativ behandelt werden. Die operative Therapie erfolgt je nach Verletzungsmuster geschlossen perkutan bzw. minimalinvasiv oder offen. Verletzungsschwere und Rekonstruktionsergebnis bestimmen die Prognose.

In advanced stages of rheumatoid arthritis (RA), the pattern of joint involvement leads to varied types of foot deformities such as forefoot, midfoot, and hindfoot deformities. We aim to evaluate midfoot and hindfoot deformities and their effect on functional outcomes in RA patients. In this prospective cross-sectional study clinical and radiological evaluations of 100 adult RA patients were studied for midfoot and hindfoot deformities. The RA disease activity, functional disability level, specific foot and ankle assessments, gait speed, and balance tests were assessed. Radiological examinations of the weight-bearing feet in a standing position were done. We found that the most frequent deformity type was the planovalgus foot (24%). There were statistically significant differences between the types of foot deformities and disease duration, disease activity, falls, Tinetti and Berg balance Test, and health assessment questionnaire-disability index. The multivariate regression analysis of independent correlates of falling detected that patients with equinovarus deformity were 2.5 times more liable for falling with 63.5% predictive power. According to the predictive criteria of deformity type for falling, the equinocavovarus type had accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 91%, 84.5%, 98.5%, 99%, and 84%, respectively. We found in RA patients, midfoot and hindfoot deformities cause a significant reduction of functional ability and quality of life. The early detection of foot deformities requires a good awareness of the clinical and radiographic diagnosis of different types of deformities thus reducing the possible functional disabilities via early management by combined orthotic, physiotherapy, and surgical treatments.

BACKGROUND: Arthrodesis of the naviculocuneiform joint (NCJ) can be performed in isolation or in conjunction with arthrodesis of other joints, often in the presence of deformity. In the literature there is relative rarity of articles reporting on results and complications of NCJ arthrodesis.
METHODS: Thirty-six patients (36 feet) with symptomatic NCJ arthritis underwent arthrodesis. Mean age was 59.1 years (SD 13.1; range 26-78) and 24 were women. Adjuvant procedures were performed simultaneously in 29 patients, whilst 17 had planovalgus and 1 had cavovarus foot deformity.
RESULTS: Union of the NCJ arthrodesis was achieved in 35 out of 36 (97.2 %) patients, whilst one patient developed non-union. Mean time to union was 13.1 weeks (SD 3.8; range 8-24). Two patients (5.6 %) developed deep infection and 5 patients (13.9 %) required secondary surgical procedures. Twenty-three patients (63.9 %) rated the outcome as good or excellent, 11 (30.6 %) as fair and 2 (5.6 %) as poor.
CONCLUSIONS: NCJ arthrodesis was part of a more complex procedure in most of the patients. Whilst union was achieved in almost all patients and complication rate was acceptable, only 64 % rated their outcome as good or excellent.
METHODS: IV.

The risk of above-ankle reamputation following a transmetatarsal amputation is around 30%. Patient selection may be crucial to achieve good outcomes, and to avoid futile operations and suffering. We are aware of no previous comparison between the two largest patient groups that undergo lower extremity amputations: patients with diabetes, and patients with non-diabetic peripheral artery disease. Patients with diabetes or nondiabetic peripheral artery disease who had undergone a transmetatarsal amputation from 2004 to 2018 at our institution were included. Patient characteristics and perioperative details were analyzed retrospectively. Subjects with diabetes were compared with subjects with nondiabetic peripheral artery disease regarding above-ankle reamputation, reamputation level, and mortality. Five-hundred-and-sixty transmetatarsal amputations in 513 subjects were included. The majority of transmetatarsal amputations (86%) occurred in diabetic subjects. Subjects with non-diabetic PAD had a higher risk of above-ankle reamputation (p = .008), and death (p < .001). At the time of data collection, only multiple-ray amputation (vs. single-ray) was an independent risk factor for above-ankle reamputation. Only age, medical comorbidity in general, and chronic heart failure were independent risk factors of death. To our knowledge, this study is the first to report marked differences in above-ankle reamputation rates and mortality following transmetatarsal amputation, comparing diabetics with non-diabetic patients with peripheral artery disease. However, the differences may be attributed to non-diabetics being older, having more medical comorbidities, and having more advanced foot ulcers at the time of transmetatarsal amputation. In patients exhibiting several of these risk factors, transmetatarsal amputation may be futile.

Navicular and cuboid fractures can be complex and difficult to treat. Depending on the mechanism of injury, diagnosis of such fractures is not always possible with conventional radiographs due to the irregularity and overlap of the midfoot bones. Advanced imaging is indicated if a fracture is of high suspicion or to further characterize a displaced fracture. Cuboid and navicular fractures can occur in isolation but are often associated with other midfoot injuries due to their anatomic relationships. Typically, nondisplaced fractures can be treated conservatively, whereas displaced fractures require surgical intervention to prevent future complications.

Tarso-metatarsal joints and naviculocuneiform joints comprising midfoot is the second most commonly involved joints following the first metatarsophalangeal joint in the foot. However, related factors of midfoot arthritis (MA) have been rarely reported. The bony structure and alignment can be more precisely assessed using Weight-Bearing Computed Tomography (WBCT) than conventional radiographs. Therefore, the aim of this study was to investigate risk factors for MA related to medical history and comorbid foot deformities using WBCT. WBCT data from September 2014 to April 2022 were extracted from a single referral hospital. All cases were divided into two groups by the presence of MA. Twenty-five potential related factors including demographics, etiology, and common co-occurring foot deformities were collected for comparison. Six hundred six cases (247 males and 359 females) among consecutive 1316 cases between September 2014 to April 2022 were selected. One hundred thirty-nine male cases (56.3%) and 210 female cases (58.5%) showed MA. In stepwise multiple logistic regression analysis, 5 factors remained statistically significant. The multivariate-adjusted odds ratios for age, laterality, body mass index (BMI), Progressive Collapsing Foot Deformity (PCFD), and lesser toe deformities (LTD) were 1.08, 1.54, 1.05, 6.62, and 3.03 respectively. Risk factors for MA associated with medical history and foot deformities included age, laterality, BMI, PCFD, and LDT.

BACKGROUND: This study analysed changes in gait and pedobarography and subjective and functional outcomes after isolated Chopart joint injury.
METHODS: The results of 14 patients were reviewed. Kinematic 3D gait analysis, comparative bilateral electromyography (EMG) and pedobarography were performed.
RESULTS: On the injured side, the 3D gait analysis showed a significantly increased internal rotation and decreased external rotation of the hip and significantly decreased adduction and decreased range of motion (ROM) for the ankle. On the healthy side, the pedobarography revealed a significantly increased mean force in the forefoot, an increased peak maximum force and an increased maximum pressure in the metatarsal. When standing, significantly more weight was placed on the healthy side. The EMG measurements showed no significant differences between the healthy and injured legs.
CONCLUSIONS: After isolated Chopart injuries, significant changes in gait and pedobarography can be seen over the long term.

Foot deformities (e.g. planovalgus and cavovarus) are very common in children with spastic cerebral palsy (CP), with the midfoot often being involved. Dynamic foot function can be assessed with 3D gait analysis including a multi-segment foot model. Incorporating a midfoot segment in such a model, allows quantification of separate Chopart and Lisfranc joint kinematics. Yet, midfoot kinematics have not previously been reported in CP.
What is the difference in multi-segment kinematics including midfoot joints between common foot deformities in CP and typically-developing feet?
103 feet of 57 children with spastic CP and related conditions were retrospectively included and compared with 15 typically-developing children. All children underwent clinical gait analysis with the Amsterdam Foot Model marker set. Multi-segment foot kinematics were calculated for three strides per foot and averaged. A k-means cluster analysis was performed to identify foot deformity groups that were present within CP data. The deformity type represented by each cluster was based on the foot posture index. Kinematic output of the clusters was compared to typically-developing data for a static standing trial and for the range of motion and kinematic waveforms during walking, using regular and SPM independent t-tests respectively.
A neutral, planovalgus and varus cluster were identified. Neutral feet showed mostly similar kinematics as typically-developing data. Planovalgus feet showed increased ankle valgus and Chopart dorsiflexion, eversion and abduction. Varus feet showed increased ankle varus and Chopart inversion and adduction.
This study is the first to describe Chopart and Lisfranc joint kinematics in different foot deformities of children with CP. It shows that adding a midfoot segment can provide additional clinical and kinematic information. It highlights joint angles that are more distinctive between deformities, which could be helpful to optimize the use of multi-segment foot kinematics in the clinical decision making process.