Introduction. The arch of the foot has been described as a truss where the plantar fascia (PF) acts as the tensile element. Its role in maintaining the arch has likely been underestimated because it only rarely torn in patients with progressive collapsing foot deformity (PCFD). We hypothesized that elongation of the plantar fascia would be a necessary and sufficient precursor of arch collapse. Method. We used a validated finite element model of the foot reconstructed from CT scan of a female cadaver. Isolated and combined simulated ligament transection models were created for each combination of the ligaments. A collapsed foot model was created by simulated transection of all the arch supporting ligaments and unloading of the posterior tibial tendon. Foot alignment angles, changes in force and displacement within each of the ligaments were compared between the intact, isolated ligament transection, and complete collapse conditions. Result. Isolated release of the PF did not cause deformity, but lead to increased force in the long (142%) and short plantar (156%), deltoid (45%), and spring ligaments (60%). The PF was the structure most able to prevent arch collapse and played a secondary role in preventing hindfoot valgus and forefoot abduction deformities. Arch collapse was associated with substantial attenuation of the spring (strain= 41%) and interosseous talocalcaneal ligaments (strain= 27%), but only a small amount in the plantar fascia (strain= 10%). Conclusion. Isolated PF release did not cause arch collapse, but arch collapse could not occur without at least 10% elongation of the PF. Simulated transection of the PF led to substantial increase in the force in the other arch supporting ligaments, putting the foot at risk of arch collapse over time. Chronic degeneration of the PF leading to plantar fasciitis may be an early sign of impending PCFD

The aim of this study was to investigate the effect of different loading scenarios and foot positions on the configuration of the distal tibiofibular joint (DTFJ). Fourteen paired human cadaveric lower legs were mounted in a loading frame. Computed tomography scans were obtained in unloaded state (75 N) and single-leg loaded stand (700 N) of each specimen in five foot positions: neutral, 15° external rotation, 15° internal rotation, 20° dorsiflexion, and 20° plantarflexion. An automated three-dimensional measurement protocol was used to assess clear space (diastasis), translational angle (rotation), and vertical offset (fibular shortening) in each foot position and loading condition. Foot positions had a significant effect on the configuration of DTFJ. Largest effects were related to clear space increase by 0.46 mm (SD 0.21 mm) in loaded dorsal flexion and translation angle of 2.36° (SD 1.03°) in loaded external rotation, both versus loaded neutral position. Loading had no effect on clear space and vertical offset in any position. Translation angle was significantly influenced under loading by −0.81° (SD 0.69°) in internal rotation only. Foot positioning noticeably influences the measurement when evaluating the configuration of DTFJ. The influence of the weightbearing seems to have no relevant effect on native ankles in neutral position

Four-dimensional computed tomography (4DCT: three dimensional + time) allows to measure individual bone position over a period of time usually during motion. This method has been found useful in studying the joints around the wrist as dynamic instabilities are difficult to detect during static CT scans while they can be diagnosed using a 4DCT scan [1]–[3]. For the foot, the PedCAT system (Curvebeam, Warrington, USA) has been developed to study the foot bones under full weight bearing, however its use is limited to static images. On the contrary, dynamic measurements of the foot kinematics using skin markers can only describe motion of foot segments and not of individual bones. However, the ability to measure individual bone kinematics during gait is of paramount importance as such detailed information could be used to detect instabilities, to evaluate the effect of joint degeneration, to help in pre-operative planning as well as in post-operative evaluation. The overall gait kinematics of two healthy volunteers were measured in a gait analysis lab (Movement Analysis Lab Leuven, Belgium) using a detailed foot-model (Oxford foot model, [4]). The measured plantar-dorsiflexion and in-eversion were used to manipulate their foot during a 4D CT acquisition. The manipulation was performed through a custom made foot manipulator that controls the position and orientation of the foot bed according to input kinematics. The manipulator was compatible with the 4D CT Scanner (Aquilion One, Toshiba, JP), and a sequence of CT scans (37 CT scans over 10 seconds with 320 slices for each scan and a slice thickness of 0.5 mm) was generated over the duration of the simulation. The position of the individual bones was determined using an automatic segmentation routine after which the kinematics of individual foot bones were calculated. To do so, three landmarks were tracked on each bone over time allowing to construct bone-specific coordinate frames. The motion of the foot bed was compared against the calculated kinematics of the tibia-calcaneus as the angles between these two bones are captured with skin markers. There is high repeatability between the imposed plantar/dorsiflexion and inversion/eversion and the calculated. Although the internal/external rotation was not imposed, the calculated kinematics follow the same pattern as the measured in the gait-analysis lab. Based on the validation of the tibia-calcaneus, the kinematics were also calculated between four other joints: tibia-talar, talar-calcaneus, calcaneus-cuboid and talar-navicular. Repeatable measurements of individual foot bone motion were obtained for both volunteers. The use of 4D CT-scanning in combination with a foot manipulator can provide more detailed information than skin marker-based gait-analysis e.g. for the study of the the tibia-talar joint. In the future, the foot manipulator will be tested for its sensitivity for specific pathologies (e.g. metatarsal coalition) and will be further developed to better resemble a real-life stance phase of gait (i.e. to include isolated heel contact and toe off)

Abstract. Objectives. Epiphysiodesis is a commonly used treatment for lower limb angular deformities. However, in recent years, distal tibial growth modulation using ‘eight plates’ or screws has emerged as an alternative treatment for paediatric foot and ankle disorders, such as CTEV. Our objective was to assess the efficacy of distal tibial modulation in correcting various paediatric foot and ankle disorders. Methods. This retrospective study analysed 205 cases of paediatric foot and ankle disorders treated between 2003 and 2022, including only cases where the eight plate or screw was fixed on the anterior surface of the distal tibia. Our aim was to measure post-operative changes in dorsiflexion, the distal tibial angle, and the tibiocalcaneal angle by examining clinical records and radiology reports. Results. We identified nine cases (nine feet) meeting the full inclusion criteria, comprising seven cases of CTEV, one case of arthrogryposis, and one case of cavovarus foot. The cohort consisted of five male and four female patients, with a mean age of 10 years and 9 months at the time of surgery. Seven cases involved the left tibia, and two cases involved the right tibia. The mean time between pre-operative X-ray to surgery was 168 days, and the mean turnaround time between surgery and post-operative X-ray was 588 days. A mean change in the distal tibial angle of 4.33 degrees was noted. However, changes in dorsiflexion were documented in only one case, which showed a change of 13 degrees. Notably, our average distal tibial angle was significantly lower than reported in the literature, at 4.33 degrees. Additionally, some studies in the literature used the Oxford Ankle Foot Questionnaire for Children to assess pre- and post-operative outcomes, but it is important to note that it is validated only for children aged 5 to 16. Furthermore, most cases reported an improved tibiocalcaneal angle except for an anomaly of 105 degrees. We assessed satisfactory patient outcomes using patient notes. Out of the 6 procured notes, one has been discharged. The rest are still under yearly or 6-monthly review and are at various stages, such as physiotherapy, removing the eight plate, or requiring further surgery. The most common presentations at review are plantaris deformity and pain. Conclusions. Our study suggests that distal tibial growth modulation can be an effective treatment option for selected paediatric foot and ankle disorders. However, due to the limited number of cases in our study, the lack of documentation of changes in dorsiflexion, and a lack of pre- and post-operative outcomes using a standardised method, further research is needed to investigate this procedure's long-term outcomes and potential complications. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

There has been a significant increase in waiting times for elective surgical procedures in orthopaedic surgery as a result of the coronavirus disease 2019 (COVID-19) pandemic. As per the hospital policy, patients awaiting elective surgery for more than 52 weeks were offered a consultant-led harm review. The aim of this study was to objectively assess the impact of this service on the field of foot and ankle surgery. The data from harm review clinics at a District General Hospital related to patients waiting to undergo elective foot and ankle procedures in the year 2021 (wait time of more than 52 weeks) were assessed. Clinical data points like change in diagnosis, need for further investigations, and patients being taken off the waiting list were reviewed. The effect of the waiting time on patients’ mental health and their perception of the service was assessed as well. A total of 72 patients awaiting foot and ankle procedures for more than 52 weeks were assessed as a part of the harm review service. It was noted that 25% of patients found that their symptoms had worsened while 66.1% perceived them to be unchanged. Twelve patients (16.9%) were sent for updated investigations. Twenty-one patients (29.5%) were taken off the waiting lists for various reasons with the most common one being other pressing health concerns; 9% of patients affirmed that the wait for surgery had a significant negative impact on their mental health. This study concludes that the harm review service is a useful programme as it helps guide changes in the diagnosis and clinical picture. The service is found to be valuable by most patients, and its impact on the service specialities and multiple centres could be further assessed to draw broad conclusions

Flat-top talus (FTT) is a complication well-known to those treating clubfoot. Despite varying anecdotal opinions, its association with different treatments, especially the Ponseti method, remains uncertain. This systematic review aimed to establish the aetiology and prevalence of FTT, as well as detailing management strategies and their efficacy. A systematic review was conducted according to PRISMA guidelines to search for articles using MEDLINE, EMBASE and Web of Science until November 2021. Studies with original data relevant to one of three questions were included: 1) Possible aetiology 2) Prevalence following different treatments 3) Management strategies and their outcomes. 32 original studies were included, with a total of 1473 clubfeet. FTT may be a pre-existing feature of the pathoanatomy of some clubfeet as well as a sequela of treatment. It can be a radiological artefact due to positioning or other residual deformity. The Ponseti method is associated with a higher percentage of radiologically normal tali (57%) than both surgical methods (52%) and non-Ponseti casting (29%). Only one study was identified that reported outcomes after surgical treatment for FTT (anterior distal tibial hemiepiphysiodesis). The cause of FTT remains unclear. It is seen after all treatment methods but the rate is lowest following Ponseti casting. Guided growth may be an effective treatment. Key words:. Clubfoot, Flat-top talus, Ponseti method, guided growth. Disclosures: The authors have no relevant disclosures

Introduction. Research studies have established mathematical correlations between the lengths of bone segments and the possible biomechanical implications of these correlations. The Lucas sequence comprises a series of integers that adhere to the same recurrence relation as the Fibonacci sequence; it differs in that it can start with any two initial integers. The purpose of this study is to determine whether segmental lengths of the foot height, tibia, femur, and upper body follow a Lucas sequence pattern. Method. This was a retrospective radiographic review of patients who underwent full-body EOS scans. The AP scan was used to measure standing foot height (Ft), tibial length (T), femoral length (Fe), upper body length (UB), and full body length. A linear regression test was performed to determine whether a Lucas sequence-based relationship exists between Ft + T and Fe, and between T + Fe and UB. Result. The regression for the relationship between Ft + T and Fe for the entire cohort (R= 0.82, R2= 0.70), the female subset (R= 0.94, R2= 0.88) and the male subset (R= 0.75, R2= 0.57), all demonstrated a strong positive correlation between Ft + T and Fe and showed that Ft + T is a likely predictor of Fe. The regression test for the entire cohort demonstrated a moderately positive correlation between T + Fe and UB (R= 0.41, R2= 0.17, F(1, 145) = 29.42, p= 2.4E-07). A stronger correlation was found for the relationship between T + Fe and UB (R= 0.57, R2= 0.32, F(1, 35) = 16.64, p= 2.5E-05) for the female subset relative to the male subset (R= 0.20, R2= 0.038, F(1, 35) = 4.37, p= 0.04). Conclusion. This study demonstrates that total height is made up of sequential segments whose lengths approximate a Lucas series. The Fibonacci sequence is therefore once again implicated in human body proportions

Ponseti method has become the most common and validated initial non-operative and/or minimally invasive treatment modality of idiopathic clubfoot regardless of the severity of the deformity worldwide. Despite hundreds of publications in the literature favoring Ponseti method, the data about secondary procedures performed in the follow-up period of clubfoot and their incidence remains sparse and given as small details in the articles. The objective of this study was to analyse our incidence of secondary procedures performed in the midterm followup period of idiopathic clubfoot patients treated with Ponseti method and review of the relevant literature. For this purpose 86 feet of 60 patients with idiopathic clubfoot who were treated with original Ponseti method were enrolled in this retrospective case control study. Unilateral ankle foot orthosis (AFO) was used rather than standart bar-connected foot abduction orthosis varying from 12 months to 25 months in the follow-up period and 74 of 86 (86%) feet required percutaneous achilles tenotomy. The average age of initial cast treatment was 12.64 days (range 1 to 102 days). The mean follow-up time was 71 months (range 19 to 153 months). Thirty seven feet of 24 patients recieved secondary procedures (43%) consisting of; supramalleolary derotational osteotomy (SMDO) (1 patient/2 feet), complete subtalar release (3 patients/5 feet), medial opening lateral closing osteotomy (double osteotomy) (2 patients/3 feet), double osteotomy with transfer of tibialis anterior tendon (TTAT) (2 patients/3 feet), partial subtalar release (PSTR) (3 patients/5 feet), PSTR with SDO (1 patient/1 foot), posterior release (PR) with repeated achillotomy (1 patient/2 feet), TTAT (6 patients/10 feet), TTAT with PR (2 patients/2 feet), TTAT with Vulpius procedure (1 patient/1 foot) and TTAT with SMDO (2 patients/3 feet) respectively. The amount of percutaneous achilles tenotomy (86%) in our study correlated with the literature which ranged from 80 to 90 %. The transfer of tibialis anterior tendon continued to be the most performed secondary procedure both in our study (51%) and in the literature, but the amount of total secondary procedures in our study (43%) was determined to be higher than the literature data varying from 7 to 27 percent which may be due to unilateral AFO application after Ponseti method for idiopathic clubfoot deformity in our study

Foot pain and related problems are quite common in the community. It is reported that 24% of individuals older than 45 experienced foot pain. Also, it is stated that at least two thirds of individuals experiences moderate physical disability due to foot problems. In the absence of evaluation of risk factors such as limited ankle dorsiflexion in the early period of the diseases (Plantar fasciitis, Achilles Tendinopathy e.g.) and the lack of mobile systems with portable remote access, foot pain becomes refractory/chronic foot pain, secondary pathologies and ends with workload of 1., 2. and 3rd level healthcare services. In the literature, manuel and dijital methods have been used to analyze the ankle range of motion (ROM). These studies are generally based on placing protractors on the image and / or angle detection from inclination measurement by using the gyroscope sensor of the mobile device. Some of these applications are effective and they are designed to be suitable for measuring in a clinical setting by a physician or physiotherapist. To the best of our knowledge, there is no system developed to measure real-time ankle ROM remotely with collaboration of the patients. In this research, we proposed to develop an ankle ROM analyze system with smart phone application that can be used comfortably by subjects. We present a case of a 22-year-old male with a symptomatic pes planus. The mobile application, which was used for data collection, was designed and implemented for Android devices. Initially, before the mobile application home page is opened, a consent page was submitted to the acceptance of individual within the scope of Law (KVKK) data privacy. Then, the participant was asked to state his sociodemographic characteristics [age, gender, height, weight] and dominant side. No history of foot-ankle injury, trauma, and surgery was recorded. Activity pain of the foot was 6 according to visual anolog scale (VAS) in the mobile application. His ankle dorsiflexion was 15 ° by manuel goniometer. Besides, server was responsible for storing the collected data and ROM measurement. ROM was calculated by processing the foot video which was sent through the mobile application. During the processing phase, a segmentation model was used which was trained with image process and deep learning methods. With the developed system, we obtained the manual goniometric measurement result with 2 degrees deviation. As the application is calibrated, it is expected to approach the actual measurement of ROM. We can conclude that mobile app-goniometer result in dorsiflexion measurement is a novel promising evaluation method for ankle ROM. it will be easy and practical to detect and monitor risk factor of the diseases, decrease medical costs, provide health services in rural areas, and contribution to life quality and to reduce the workload on physicians and physiotherapist

In podiatric medicine, diagnosis of foot disorders is often merely based on tests of foot function in static conditions or on visual assessment of the patient's gait. There is a lack of tools for the analysis of foot type and for diagnosis of foot ailments. In fact, static footprints obtained via carbon paper imprint material have traditionally been used to determine the foot type or highlight foot regions presenting excessive plantar pressure, and the data currently available to podiatrists and orthotists on foot function during dynamic activities, such as walking or running, are scarce. The device presented in this paper aims to improve current foot diagnosis by providing an objective evaluation of foot function based on pedobarographic parameters recorded during walking. 23 healthy subjects (16 female, 7 males; age 35 ± 15 years; weight 65.3 ± 12.7; height 165 ± 7 cm) with different foot types volunteered in the study. Subjects' feet were visually inspected with a podoscope to assess the foot type. A tool, comprised of a 2304-sensor pressure plate (P-walk, BTS, Italy) and an ad-hoc software written in Matlab (The Mathworks, US), was used to estimate plantar foot morphology and functional parameters from plantar pressure data. Foot dimensions and arch-index, i.e. the ratio between midfoot and whole footprint area, were assessed against measurements obtained with a custom measurement rig and a laser-based foot scanner (iQube, Delcam, UK). The subjects were asked to walk along a 6m walkway instrumented with the pressure plate. In order to assess the tool capability to discriminate between the most typical walking patterns, each subject was asked to walk with the foot in forcibly pronated and supinated postures. Additionally, the pressure plate orientation was set to +15°, +30°, −15° and −30° with respect to the walkway main direction to assess the accuracy in measuring the foot progression angle (i.e. the angle between the foot axis and the direction of walk). At least 5 walking trials were recorded for each foot in each plate configuration and foot posture. The device allowed to estimate foot length with a maximum error of 5% and foot breadth with an error of 1%. As expected, the arch-index estimated by the device was the lowest in the cavus-feet group (0.12 ± 0.04) and the highest in the flat-feet group (0.29 ± 0.03). These values were between 4 – 10 % lower than the same measurements obtained with the foot scanner. The centre of pressure excursion index [1] was the lowest in the forcibly-pronated foot and the largest in the supinated foot. While the pressure plate used here has some limitations in terms of spatial resolution and sensor technology [2], the tool appears capable to provide information on foot morphology and foot function with satisfying accuracy. Patient's instrumental examination takes only few minutes and the data can be used by podiatrists to improve the diagnosis of foot ailments, and by orthotists to design or recommend the best orthotics to treat the foot condition

Compartment syndrome of the foot requires urgent surgical treatment. Currently, there is still no agreement on the number and location of the myofascial compartments of the foot. The aim of this cadaver study was to provide an anatomical basis for surgical decompression in the event of compartment syndrome. We found that there were three tough vertical fascial septae that extended from the hindfoot to the midfoot on the plantar aspect of the foot. These septae separated the posterior half of the foot into three compartments. The medial compartment containing the abductor hallucis was surrounded medially by skin and subcutaneous fat and laterally by the medial septum. The intermediate compartment, containing the flexor digitorum brevis and the quadratus plantae more deeply, was surrounded by the medial septum medially, the intermediate septum laterally and the main plantar aponeurosis on its plantar aspect. The lateral compartment containing the abductor digiti minimi was surrounded medially by the intermediate septum, laterally by the lateral septum and on its plantar aspect by the lateral band of the main plantar aponeurosis. No distinct myofascial compartments exist in the forefoot. Based on our findings, in theory, fasciotomy of the hindfoot compartments through a modified medial incision would be sufficient to decompress the foot

Tenodesis effect and digital cascade of the foot were never described in the current literature. However, understanding of these effects are important in the diagnoses and managements of foot flexor tendon rupture and lesser toe deformities. We aim to investigate the presence of these effects in the foot with intact and cut tendons. Ten fresh frozen cadaveric specimens were used in our study. 2. nd. , 3. rd. and 4. th. toe metatarsophalangeal joint (MTPJ) and proximal interphalangeal joint (PIPJ) range of motion (ROM) at ankle resting position were measured. Same measurements were repeated with maximum ankle plantarflexion and dorsiflexion. 4. th. toe Flexor Digitorum Longus (FDL) was then identified over plantar aspect of metatarsal shaft and cut transversely. 2. nd. , 3. rd. and 4. th. toe MTPJ and PIPJ ROM at ankle resting position, maximum plantarflexion and dorsiflexion were then measured. Mean 4. th. toe MTPJ and PIPJ ROM at ankle dorsiflexion were 13.5 ° of dorsiflexion and 25 ° of plantarflexion respectively, compared with values at ankle plantarflexion which were 35 ° and 25 ° respectively. After 4. th. toe FDL was cut, mean 4. th. toe MTPJ and PIPJ ROM at ankle dorsiflexion were 14 ° and 24 ° respectively and at ankle plantarflexion the values were 34.5 ° and 25 ° respectively. At ankle resting position before 4. th. FDL was cut, mean 4. th. toe MTPJ and PIPJ ROM were 22 ° and 31 ° respectively, compared with the values after 4. th. FDL was cut, ie 22.5 ° and 30.5 ° respectively. Tenodesis effect of the foot was shown in our study. However unlike in hand, this effect was only present in MTPJ and was still present following cut FDL. Similarly, digital cascade was still present following cut FDL. The maintenance of tenodesis effect and digital cascade following cut flexor tendon is likely contributed by various soft tissue restraints and intrinsic muscle actions. These findings are important in both the diagnosis and management of foot flexor tendon rupture and help us to better understand the biomechanics of lesser toe deformities and the managements of these deformities

Abstract. Skeletal kinematics are traditionally measured by motion analysis methods such as optical motion capture (OMC). While easy to carry out and clinically relevant for certain applications, it is not suitable for analysing the ankle joint due to its anatomical complexity. A greater understanding of the function of healthy ankle joints could lead to an improvement in the success of ankle-replacement surgeries. Biplane video X-ray (BVX) is a technique that allows direct measurement of individual bones using highspeed, dynamic X-Rays. Objective. To develop a protocol to quantify in-vivo foot and ankle kinematics using a bespoke High-speed Dynamic Biplane X-ray system combined with OMC. Methods. Two healthy volunteers performed five level walks and step-down trials while simultaneous capturing BVX and synchronised OMC. participants undertook MR imaging (Magnetom 3T Prisma, Siemens) which was manually segmented into 3D bone models (Simpleware Scan IP, Synopsis). Bone position and orientation for the Talus, Tibia and Calcaneus were calculated by manual matching of 3D Bone models to X-Rays (DSX Suite, C-Motion, Inc.). OMC markers were tracked (QTM, Qualisys) and processed using Visual 3D (C-motion, Inc.). Results. Initial results for level walking showed that OMC overestimated the rotational range of motion (ROM) in all three planes for the tibiotalar joint compared with BVX (Sagittal: OMC 30°/BVX 20°, Frontal: OMC 16°/BVX 15° and Transverse: OMC 20°/BVX 17°). For the subtalar joint, OMC (22°) over-estimated sagittal ROM compared with BVX (14°) and underestimated the ROM in the other planes (Frontal: OMC 8°/BVX 15° and Transverse: OMC 18°/BVX 20°). Conclusions. The results highlight the discrepancy between OMC and BVX methods. However, the BVX results are consistent with previous literature. The protocol developed here will form the foundation of future patient-based studies to investigate in-vivo ankle kinematics. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

A complete design-manufacturing process for delivering customized foot orthoses by means of digital technologies is presented. Moreover, this feasibility study aims to combine a semi-automatic modelling approach with the use of low-cost devices for 3D scanning and 3D printing. In clinical practice, traditional methods for manufacturing customized foot orthoses are completely manual, mainly based on plaster casting plus hand fabrication, and are widely used among practitioners. Therefore, results depend on skills and expertise of individual orthoptists and podiatrists that need considerable training and practice in order to obtain optimal functional devices. On the other side, novel approaches for design and manufacturing customized foot orthoses by means of digital technologies (generally based on 3D scanning, 3D modelling and 3D printing) are recently reported as a valid alternative method to overcome these limitations. This study has been carried out in an interdisciplinary approach between the staff of Design and Methods in Industrial Engineering and the staff of Podology with the aim to assess the feasibility of a novel user-friendly and cost-effective solution for delivering customized functional foot orthoses. More specifically, a Generative Design (GD) workflow has been developed to enable practitioners without enough CAD skills to easily 3D modelling and interactively customize foot orthoses. Additionally, low-cost devices for 3D scanning and 3D printing that have been acquired by the Podology Lab, were also tested and compared with the high-cost ones of the Department of Industrial Engineering. The complete process is divided into three main steps. The first one regards the digitization of the patient's foot by means of 3D laser scanner devices. Then a user-friendly 3D modelling approach, developed for this purpose as GD workflow, allows interactively generating the customized foot orthosis, also adjusting several features and exporting the watertight mesh in STL format. Finally, the last step involves Additive Manufacturing systems to obtain the expected physical item ready to use. First, for what concerns the digitizing step, the acquired data resulting from 3D scanning by means of the low-cost system (Sense 3D scanner) appears accurate enough for the present practical purposes. Then, with respect to the 3D modelling step, the proposed GD workflow in Grasshopper is intuitive and allows easily and interactively customizing the final foot orthosis. Finally, regarding the Additive Manufacturing step, the low cost 3D printer (Wasp Delta 40 70) is capable to provide adequate results for the shell of the foot orthosis. Moreover, this system appears really versatile in reason of the capability to print in a wide range of different filaments. Therefore, since the market of 3D printing filaments is rapidly growing, building sessions with different materials (both flexible and rigid such, for example, PLA, AB and PETG) were completed. This study validated, in terms of feasibility, that the use of a GD modelling approach, in combination with low-cost devices for 3D scanning and 3D printing, is a real alternative to conventional processes for providing customized foot orthosis. Moreover, the interdisciplinary approach allowed the transfer of skills and knowledge to the practitioners involved and, also, the low-cost devices Sense 3D scanner and Wasp Delta 40 70 that have been acquired by the Podology Lab, were demonstrated suitable for this kind of applications

The incidence of wound complications after a hip or a knee replacement is well established, but there is no such data about foot/ankle surgery. Without this data it is difficult to compare performance between different care-providers. It is also difficult to benchmark services that could potentially be provided by a wide range of care providers (chiropodists, podiatrists, podiatric surgeons, general orthopaedic surgeons with a small foot/ankle practice, etc). Our aim was to establish the incidence of wound complications after foot/ankle surgery and provide a baseline for future comparison. Our study was done in two parts. First part was to conduct an opinion-survey of BOFAS members with a substantial foot/ankle practice, on wound complications from foot/ankle surgery in their own practice. Second part was to conduct a prospective study on the incidence of wound complications from our own foot/ankle practice. The study was registered as an audit and did not require ethical approval. All wound complications (skin necrosis, wound dehiscence, superficial and deep infections) were recorded prospectively. Record of such data was obtained by an independent observer, and from multiple sources, to avoid under-reporting. 60 % of the responders to our survey had a predominant foot/ankle practice (exclusive or at least 75 % of their practice was foot/ankle surgery) and were included for further analysis of their responses. A large majority of these responders (64%) reported a rate of 2–5 % for superficial infection, and a significant majority (86 %) reported a deep infection rate of less than 2 %. Results from our own practice showed an incidence of superficial infection of 2.8 % and deep infection of 1.5 %. With increasing focus on clinical outcome measures as an indicator of quality, it is imperative to publish data on wound complications/ infection after foot/ankle surgery, and in the absence of such data, our two-armed study (survey-opinion and prospective audit) provides a useful benchmark for future comparisons

An adult acquired flatfoot deformity (AAFD) is a complex 3D deformity. Surgical correction consists of a medial calcaneal osteotomy (MCO) but shows limitations due to the current 2D assessment. Therefore, the aim is to determine the influence of an MCO on the longitudinal foot arch assessed by 2D and 3D weightbearing CT (WBCT). Seventeen patients with a mean age of 44,5 years (range 18–66 yrs) were retrospectively included. MCO was indicated in a stage II AAFD (N=15) and a post-traumatic valgus deformity (N=2). Pre- and post-operative imaging was obtained from a WBCT. The height of the longitudinal foot arch was measured as the distance from the navicular tuberositas to the floor (Navicular Height, NH) on 2D CT images (NH. 2D. ) and computed on 3D CT data (NH. 3D. ). Additionally, 3D assessment could compute the degree of exorotation (α) of the navicular bone towards the vertical axis. The mean pre-operative NH. 2D. and NH. 3D. were respectively 29.57mm ± 7.59 and 28.34mm ± 6.51. These showed to be statistically different from the mean post-operative NH. 2D. and NH. 3D. , respectively 31.62mm ± 6.69 and 31.67mm ± 6.47 (p < 0,001). A statistical difference was also found when comparing the mean degree of exorotation in pre- and post-operative, respectively: α. pre. =14.08° ± 4,92 and the α. post. =19,88° ± 3.50 (p < 0,001). This study demonstrates a significant correction of the longitudinal foot arch after a MCO. The novelty is attributed to the accurate degree of rotation assessment using WBCT. This information could be assistive to optimise a pre-operative planning

The flat foot is a frequent deformity in children and results in various levels of functional alterations. A diagnosis based on foot morphology is not sufficient to define the therapeutic approach. In fact, the degree of severity of the deformity and the effects of treatments require careful functional assessment. In case of functional flatfoot, subtalar arthroereisis is the surgical treatment of choice. The aim of this study is to evaluate and compare the functional outcomes of two different bioabsorbable implants designed for subtalar arthroereisis in childhood severe flat foot by means of thorough gait analysis. Ten children (11.3 ± 1.6 yrs, 19.7 ± 2.8 BMI) were operated for flat foot correction [1,2] in both feet, one with the calcaneo-stop method, i.e. a screw implanted into the calcaneus, the other with an endoprosthesis implanted into the sinus-tarsi. Gait analysis was performed pre- and 24 month post-operatively using a 8-camera motion system (Vicon, UK) and a surface EMG system (Cometa, Italy) to detect muscular activation of the main lower limb muscles. A combination of established protocols, for lower limb [3] and multi-segment foot [4] kinematic analysis, was used to calculate joint rotations and moments during three level walking trials for each patient. At the foot, the tibio-talar, Chopart, Lisfranc, 1. st. metatarso-phalangeal joints were tracked in three-dimensions, together with the medial longitudinal arch. Significant differences in standard X-ray measurements were observed between pre- and post-op, but not between the two treatment groups. Analysis of the kinematic variables revealed functional improvements after surgery. In particular, a reduction of eversion between the shank and calcaneus (about 15° on average) and a reduction of inversion between metatarsus and calcaneus (about 18° on average) were detected between pre- and post-operatively after both treatments. Activation of the main plantar/dorsiflexor muscles was similar at both pre- and post-op assessments with both implants. The combined lower limb and multi-segment foot kinematic analyses were found adequate to provide accurate functional assessment of the feet and of the lower limbs. Both surgical treatments restored nearly normal kinematics of the foot and of the lower limb joints, associated also to a physiologic muscular activation

Summary Statement. Treatment of non-union is a highly demanding field with respect to bone healing. BMP 7 is a useful, wide-ranged tool in treating non-union of the foot and benign bone tumors. It represents a low-risk procedure with a high level of reliability. Introduction. Treatment of non-union is a highly demanding field with respect to bone healing. Treatment of tibial fracture non-union with the bone morphogenetic protein 7 (BMP-7) has been successfully reported. BMP 7 is a recombinant human protein produced in ovary cells of the Chinese hamster. It is responsible for the differentiation of mesenchymal stem cells from the periost, muscle and sponious bone and stimulates bone formation. It is the aim of our study to investigate the use of BMP 7 for other locations than the tibia, such as the foot and benign bone tumors. We strive for union or revision in each medical case. Patients & Methods. At our clinic we applied BMP-7 to 13 patients (9 patients with non-union, 4 patients with benign bone cysts). 9 patients with non-union of the foot (4 forefoot, 1 midfoot, 3 hindfoot, 1 tibia) were surgically treated by resection, stabilisation, and application of BMP 7. The study included 5 men and 4 women at an average age of 58,4 years (range 33 – 80), 13 previous surgeries had been carried out. The period of follow up was on average 16.3 months (5 – 40 months). The indication for using BMP-7 instead of autologous bone graft was poor local blood supply, poor local soft tissue because of previous interventions and risk factors like smoking and diabetes. Following an indicated open biopsy, the 4 cases of benign bone tumors (1 juvenile bone cyst of the talus, 1 osteofibrose dysplasia of the proximal tibia and 2 juvenile bone cysts of the proximal humerus) were all treated with resection, followed by an application of BMP-7 and external or internal fixation. In addition two received bone grafting and two received cortisone. The average age of the tumor group was 16,75 years (11–24 years, 2 male, 2 female). Results. At follow-up all patients were satisfied with respect to pain and function, no operative complications had occurred and bone fusion had finished in 7 patients after 3 months. One ankle joint had a fibrous fusion but was free of pain. One arthrodesis of the first metatarsophalangeal joint was turned into a resection arthroplasty, today the patient is free of pain and uses a normal shoe. Both bone cysts have the radiological evidence of rehabilitation. At one humeruscyst we removed the TENS-nails without complications. We had no complications like heterotopic ossification, local erythema or pressure sensitivity. Discussion/Conclusion. These results show that BMP 7 is a useful, wide-ranged tool in treating non-union of the foot and benign bone tumors. It represents a low-risk procedure with a high level of reliability

Complex Regional Pain Syndrome (CRPS) is regarded as an uncommon clinical complication to orthopaedic surgery. Few have looked into its prevalence in foot and ankle surgery. This is a retrospective cohort study of all patients undergoing foot and ankle surgery, operated on by the foot and ankle team in our department in 2009. The objectives of this study was to determine the prevalence CRPS in these patients post-operatively and to examine the associated factors. 17 patients from 390 (4.4%) were identified as meeting the IASP (International Association for the Study of Pain) criteria for the diagnosis of CRPS. Of these, the majority were female (n = 14, 82.4%) and the average age was 47.2 (SD 9.7). All were elective patients. The majority involved operating on the forefoot (n = 9, 52.9%), followed by the hindfoot and ankle (3 cases each, 17.6%). Most of these patients had new onset CRPS (n = 12, 70.6%), with no previous history of the condition. 3 patients (17.6%) had documented nerve damage and therefore suffered from CRPS Type 2. Blood results were available for 14 (82.4%) patients at a minimum of 3 months post-operatively, and none had elevated inflammatory markers. 5 of the patients (29.4%) were smokers and 8 (47.1%) had a pre-existing diagnosis of anxiety or depression. At present, based on our findings, we recommend that middle-aged women, with a history of anxiety or depression, undergoing elective foot surgery be specifically counselled on the risk of developing CRPS at consenting. We recommend similar studies to be undertaken in other West of Scotland orthopaedic units

Summary Statement. An alternative way to assess three dimensional skin motion artefacts of kinematic models is presented and applied to a novel kinematic foot model. Largest skin motion is measured in the tarsal region. Introduction. Motion capture systems are being used in daily clinical practise for gait analysis. Last decade several kinematic foot models have been presented to gain more insight in joint movement in various foot pathologies. No method is known to directly measure bone movement in a clinical setting. Current golden standard is based on measurement of motion of skin markers and translation to joint kinematics. Rigid body assumptions and skin motion artefacts can seriously influence the outcome of this approach and rigorous validation is required before clinical application is feasible. Validation of kinematic models is currently done via comparison with bone pin studies. However, these studies can only assess major bones in a highly invasive way; another problem is the non-synchronous measurement of skin markers and bone pins. Recently the Glasgow Maastricht kinematic foot model, which comprises all 26 foot segments, has been presented. To validate the model we propose a novel non-invasive method for the assessment of skin motion artefact, involving loaded CT data. Patients & Methods. 25 subjects (healthy and pathological feet) have undertaken CT scans. These CT-scans have been obtained in 1 unloaded and 3 varying loading conditions. CT-slices are 3D reconstructed and segmented. The principal axes of the segmented bones were derived from the surface points of the bones. These principal axes are used to compute bone orientation. Subsequently, coordinate systems of bones in the different loading conditions were matched. Markers were translated and rotated to orientations of their corresponding bones. Maximal distance between markers is calculated per subject to asses the influence of skin motion. Results. Preliminary results of 9 subjects show largest positional differences for markers associated with the cuneiform lateralis (5.7 ± 3.2 mm) and cuneiform intermedium (7.7 ± 3.7 mm). Smallest positional differences are found on the hallux proximalis (0.9 ± 0.34mm). Spatial resolution is too small to accurately calculate orientation of smaller bones, therefor distal phalanges 2–5 are not taken into account in the analysis. Discussion/Conclusion. Skin motion is a major cause of inaccuracy in gait analysis. This is the first study presenting an automated non-invasive method to calculate the 3D orientation of skin markers with respect to the coordinate system of the corresponding bone(s). Largest skin motion is measured in the tarsal region. Future work will be in calculation of the effect of skin motion in the accuracy of joint angle calculation