[Foot injuries in the emergency room : three lesions that should not be missed]. / Traumatismes du pied aux urgences : attention à trois lésions pièges.

Urgent consultations for foot injuries are common. Trauma injuries are often obvious, such as displaced or open fractures, dislocations, or tissue breakdown. However, they can also have a subtle presentation and still hide severe structural damage. This is the case of «benign¼ Lisfranc sprains, compartment syndrome or even tendon sections through an apparently benign wound. The purpose of this article is to help the primary care physician to be aware of these subtle and sometimes hidden injuries, to assist him in the diagnosis and to provide the keys to appropriate treatment.

Les consultations en urgence pour une blessure du pied sont fréquentes. Les lésions consécutives aux traumatismes sont souvent évidentes et on ne passera certainement pas à côté d'une fracture déplacée, voire ouverte, d'une luxation articulaire ou d'un délabrement de l'enveloppe tissulaire. Toutefois, les lésions peuvent aussi se présenter de manière subtile et cacher quand même une atteinte structurelle sévère. C'est le cas des entorses « bénignes ¼ du Lisfranc, du syndrome des loges ou encore des sections tendineuses à travers une plaie d'apparence anodine. Le but de cet article est de rendre le médecin de premier recours attentif à ces atteintes parfois cachées, de l'aider dans sa démarche diagnostique et de lui donner les clés du traitement adéquat.

Automatic Body Segment and Side Recognition of an Inertial Measurement Unit Sensor during Gait.

Inertial measurement unit (IMU) sensors are widely used for motion analysis in sports and rehabilitation. The attachment of IMU sensors to predefined body segments and sides (left/right) is complex, time-consuming, and error-prone. Methods for solving the IMU-2-segment (I2S) pairing work properly only for a limited range of gait speeds or require a similar sensor configuration. Our goal was to propose an algorithm that works over a wide range of gait speeds with different sensor configurations while being robust to footwear type and generalizable to pathologic gait patterns. Eight IMU sensors were attached to both feet, shanks, thighs, sacrum, and trunk, and 12 healthy subjects (training dataset) and 22 patients (test dataset) with medial compartment knee osteoarthritis walked at different speeds with/without insole. First, the mean stride time was estimated and IMU signals were scaled. Using a decision tree, the body segment was recognized, followed by the side of the lower limb sensor. The accuracy and precision of the whole algorithm were 99.7% and 99.0%, respectively, for gait speeds ranging from 0.5 to 2.2 m/s. In conclusion, the proposed algorithm was robust to gait speed and footwear type and can be widely used for different sensor configurations.

Posterior to anterior malleolar extended lateral approach to the ankle (PAMELA): early results of a novel approach.

INTRODUCTION: In a previous cadaveric study, we described the Posterior to Anterior Malleolar Extended Lateral Approach (PAMELA) to address complex ankle fractures. It was demonstrated to provide optimal exposure of the posterior and lateral malleoli, and of the anterolateral portion of the ankle through a single incision. The aim of this study is to report the clinical results of this novel approach. METHODS: Between January 2019 and January 2021, all patients presenting with a complex ankle fracture in our institution were assessed by CT scan. Indication to use the PAMELA was determined by the fracture pattern, according to our previous guidelines, including combination of complex lateral and displaced posterior malleolar fractures, associated in most cases with anterolateral fracture avulsion. The approach was performed according to the steps previously described. Intraoperative evaluation included quality of exposure, ease of performing the osteosynthesis, and any complication encountered. The postoperative course was assessed for wound healing, quality of reduction, and the occurrence of any complication. RESULTS: The PAMELA was performed in 20 patients (aged 17-73). The most common combination of fractures was a comminuted lateral malleolus fracture associated with a displaced fracture of the posterior malleolus and a Wagstaffe-Le Fort or Chaput avulsion. We encountered no intraoperative complication. X-rays showed anatomical reduction in all cases. Postoperative complications included three delayed wound healing resolved with local treatment and one sural nerve traction injury. CONCLUSIONS: The main potential concern regarding this novel approach was the healing of the flap. Our results reject this concern and are in line with wound healing complications reported following surgical treatment of ankle fractures. This study confirms the safe in vivo feasibility of the PAMELA and opens a new perspective in the optimal management of complex fractures of the ankle. A larger prospective clinical study is ongoing in our institution.

Knee adduction moment decomposition: Toward better clinical decision-making.

Knee adduction moment (KAM) is correlated with the progression of medial knee osteoarthritis (OA). Although a generic gait modification can reduce the KAM in some patients, it may have a reverse effect on other patients. We proposed the "decomposed ground reaction vector" (dGRV) model to 1) distinguish between the components of the KAM and their contribution to the first and second peaks and KAM impulse and 2) examine how medial knee OA, gait speed, and a brace influence these components. Using inverse dynamics as the reference, we calculated the KAM of 12 healthy participants and 12 patients with varus deformity and medial knee OA walking with/without a brace and at three speeds. The dGRV model divided the KAM into four components defined by the ground reaction force (GRF) and associated lever arms described with biomechanical factors related to gait modifications. The dGRV model predicted the KAM profile with a coefficient of multiple correlations of 0.98 ± 0.01. The main cause of increased KAM in the medial knee OA group, the second component (generated by the vertical GRF and mediolateral distance between the knee and ankle joint centers), was decreased by the brace in the healthy group. The first peak increased, and KAM impulse decreased with increasing velocity in both groups, while no significant change was observed in the second peak. The four-component dGRV model successfully estimated the KAM in all tested conditions. It explains why similar gait modifications produce different KAM reductions in subjects. Thus, more personalized gait rehabilitation, targeting elevated components, can be considered.

[Six pitfalls around the ankle sprains]. / Entorses de cheville : six pièges à connaître.

Ankle sprains are frequently encountered. They result most of the time in lesions of the lateral ligament complex. Nevertheless, in the context of an ankle sprains, more severe injuries including fracture of the lateral process of the talus, fracture of the base of the 5th metatarsal, tear of the medial ligament complex, lesion of the syndesmosis, sprain of the Chopart joint, and peroneal tendons luxation are potentially overlooked and, if treated inadequately, may be associated with poor functional outcome. The goal of the present paper is to make the emergency practitioner aware of these potential lesions, and to help him making the correct diagnosis in order to initiate the adequate treatment.

Les entorses de cheville sont un motif de consultation très fréquent. Dans la plupart des cas, elles se limitent à des lésions de l'appareil ligamentaire externe. Toutefois, elles peuvent masquer des lésions plus graves incluant les fractures du processus latéral du talus, de la base du 5e métatarsien, les lésions ligamentaires internes, de la syndesmose, les entorses du Chopart et la luxation des tendons fibulaires. Il n'est pas toujours facile de poser le bon diagnostic en urgence et une prise en charge initiale insuffisante de ces lésions peut hypothéquer significativement le pronostic fonctionnel. Le but de cet article est de rendre le praticien de premier recours attentif à ces lésions potentielles et de l'aider à poser le bon diagnostic en vue d'un traitement initial adéquat.

Impact of foot modeling on the quantification of the effect of total ankle replacement: A pilot study.

BACKGROUND: Kinematic and kinetic foot models showed that computing ankle joint angles, moments and power with a one-segment foot modeling approach alters kinematics and tends to overestimate ankle joint power. Nevertheless, gait studies continue to implement one-segment foot models to assess the effect of total ankle replacement. RESEARCH QUESTION: The objective of this pilot study was to investigate the effect of the foot modeling approach (one-segment versus multi-segment) on how total ankle replacement is estimated to benefit or degrade the patient's biomechanical performance. METHODS: Ten subjects with post-traumatic ankle osteoarthritis scheduled for total ankle replacement and 10 asymptomatic subjects were recruited. A one-segment and a multi-segment foot model were used to calculate intrinsic foot joints kinematics and kinetics during gait. A linear mixed model was used to investigate the effect of the foot model on ankle joint kinematic and kinetic analysis and the effect of total ankle replacement. RESULTS: Differences in range of motion due to the foot model effect were significant for all the gait subphases of interest except for midstance. Peak power generation was significantly overestimated when computed with the one-segment foot model. Ankle and shank-calcaneus joint dorsi-/plantarflexion range of motion did not increase post-operatively except during the loading response phase. A significant 'group' effect was found for stance and pre-swing phase range of motion, with total ankle replacement patients showing lower range of motion values than controls for dorsi/plantarflexion. SIGNIFICANCE: The outcome of this study showed that the 'foot model' had a significant effect on estimates of range of motion and power generation. The findings in our study therefore emphasize the clinical interest of multi-segment foot modeling when assessing the outcome of a therapeutic intervention.

Posterior to anterior malleolar extended lateral approach to the ankle (PAMELA): a cadaveric anatomic study.

INTRODUCTION: The posterolateral approach is used in most cases of surgical treatment of ankle fractures involving the posterior and lateral malleoli. However, this approach does not allow access to the anterolateral structures of the ankle, which represent important landmarks to allow an anatomical reduction in case of complex ankle fracture. Our objective is to propose a novel surgical approach for optimal management of injuries including both a fracture of the posterior malleolus and a complex lesion of the lateral and/or anterolateral portions of the ankle. METHODS: Cadaveric dissection, including a vascular study, was performed on eight specimens. Assessment included density of the vascular supply around the lateral malleolus, identification of the structures at risk, quality of exposure of the bony structures, and convenience of hardware fixation. RESULTS: The cutaneous flap benefits from a rich interconnected arterial supply. Structures at risk, including the superficial peroneal and sural nerves, the lesser saphenous vein, and the peroneal artery are easily identified and protected. The interval between the peroneal tendons and the flexor hallucis longus muscle provides optimal access to the posterior malleolus. The lateral malleolus is exposed by retracting the peroneal tendons medially. An anterolateral arthrotomy, respecting the anterior talofibular and tibiofibular ligaments, offers a sharp view on the talo-tibio-fibular junction. Hardware placement can be done with optimal access to any exposed surfaces. CONCLUSIONS: The PAMELA opens a new perspective in the optimal management of complex fractures of the ankle. The approach allows optimal exposure to address fractures of the posterior malleolus, of the lateral malleolus, and of the anterolateral portion of the ankle through a single incision. Application in clinical practice is the subject of a future study in our institution.

Bilateral gait asymmetry associated with tibiotalocalcaneal arthrodesis versus ankle arthrodesis.

BACKGROUND: Gait asymmetries have been reported following ankle arthrodesis. However, similar reports do not exist for tibiotalocalaneal arthrodesis (TTCA), which involves further articular fusion. This study aimed to assess the extent of gait asymmetry following TTCA when compared to ankle arthrodesis. METHOD: Gait assessment was performed on 36 participants, including 12 ankle arthrodesis, 12 TTCA and 12 controls - using 3-D inertial sensors and pressure insoles. 48 gait parameters were monitored on both operated and non-operated sides. Questionnaires including AOFAS, FAAM, EQ-5D were used to assess both operative groups, comparatively. RESULTS: Both operative groups reported significantly smaller stride, slower walking speed, altered stance phase with longer loading and shorter push-off compared to controls. Joint range of motion was significantly reduced on the operated side of both operative groups at hindfoot, forefoot and toe intersegments. However, the ankle arthrodesis group reported a significantly higher alteration compared to controls in maximum contact force and pressure distribution. Furthermore, bilateral comparison showed extended gait asymmetry in the ankle arthrodesis group with 29 out of 48 parameters being significantly different between the two sides, whereas only 16 out of 48 gait parameters showed bilateral difference in the TTCA group. CONCLUSION: Both ankle salvage operations led to significant gait alteration and bilateral asymmetry. However, extended joint restriction in TTCA does not seem to worsen the gait outcomes. Further investigation is needed to understand the long-term impact of altered gait, on neighboring joints, following TTCA.

Calcaneocuboid and Naviculocuneiform Dislocation: An Unusual Injury of the Midfoot.

Introduction. Midfoot dislocations are rare traumatic injuries. The best known patterns involve the Lisfranc and Chopart joints, although some other types have been described. Dislocations that occur at the level of the naviculocuneiform and calcaneocuboid joints simultaneously represent a very rare configuration of dislocation. Case Presentation. A 34-year-old man sustained a crush injury to his left foot causing a complete dislocation through the naviculocuneiform and calcaneocuboid joints. Immediate closed reduction and percutaneous pinning were performed, followed by open reduction and stabilization of both joints two weeks later. Anatomical reduction was obtained, and the clinical outcome remained satisfactory 10 months after surgery. Discussion. Anatomical reduction is essential to obtain favorable outcomes in traumatic midfoot injuries. An unusual pattern of midfoot dislocation can be treated according to the same principles as those for classical Lisfranc or Chopart injuries.

Long-term evaluation of the distal transverse plantar approach for Morton's neuroma excision.

BACKGROUND: There is currently no consensus on the ideal approach for the operative treatment of Morton’s neuroma. The distal transverse plantar approach aims at optimal exposure without the scar complications associated with the longitudinal plantar approach. Long-term evaluation based on validated outcome instruments is lacking. The main purpose of this retrospective study was to evaluate the long-term clinical outcome of this approach using validated function and scar evaluation scores. METHODS: Forty-nine patients operated on at our institution were examined clinically by two independent observers using the Foot and Ankle Ability Measure (FAAM) and the Vancouver Scar Scale (VSS). Patients who underwent neurectomy alone and those who had additional foot surgery were compared. RESULTS: Assessment at a mean of 7.9 years (range 4–12) postoperatively revealed a mean FAAM score of 84.8 ± 25% and a mean VSS score of 1.57 ± 1.7. Patients who underwent neurectomy alone had higher FAAM scores at follow up. We observed no complication that required an additional procedure. CONCLUSIONS: The transverse plantar approach results in good objective outcome scores, including scar healing, in the long term. This is our preferred technique because, in our experience, it offers optimal visualisation of the nerve, does not require deep dissection and allows the exposure of two adjacent web spaces of the foot through a single incision.

Association of Bosworth, Pilon, and Open Talus Fractures: A Very Unusual Ankle Trauma.

INTRODUCTION: A Bosworth fracture-dislocation is a rare lesion resulting in a fixed dislocation of the distal fibula behind the posterior tibial tubercle. Only few cases have been reported showing an associated consequent fracture, namely, a pilon or a medial malleolus fracture. CASE REPORT: We present a case report of a patient with an unusual combination of a Bosworth injury with a pilon fracture and an open multifragmentary talus fracture and our approach for open reduction and internal fixation. At one year postoperative, the patient developed an invalidating tibiotalar and subtalar arthrosis that eventually required an ankle-hindfoot arthrodesis. A Bosworth injury is an infrequent entity and is even rarer when associated with other fractures. Careful preoperative planning is necessary, as the combination of these fractures is a surgical challenge. Special care must be taken to preserve the neurovascular bundle. DISCUSSION: The present case highlights a Bosworth injury involving a severity that has never been described before and suggests adding an eighth stage to the classification presented by Perry et al.

Preoperative gait asymmetry in end-stage unilateral ankle osteoarthrosis patients.

BACKGROUND: Gait asymmetries following unilateral ankle surgeries have been reported in published literature. Preoperative compensatory gait patterns are usually assumed to be the cause; however, this hypothesis is not backed by objective data. This study aims to assess gait symmetry in patients with unilateral ankle osteoarthrosis (AOA). METHOD: 20 participants, including 10 controls and 10 AOA patients, were assessed using 3-D inertial sensors and pressure insoles. 46 gait parameters and foot sub-region relative motions were studied. RESULTS: Compared with the controls, significant differences were reported in 23 parameters on the affected side and 20 on the unaffected side. AOA bilateral comparison reported differences in 14 parameters, mostly in the toe region. Asymmetries were also found in forefoot relative motion. CONCLUSION: Gait alterations are reported in AOA. One-third of measured parameters and forefoot relative motion reported marked gait asymmetries. Clarification of the origin of postoperative gait imbalances is likely to help clinicians optimize rehabilitation programs.

[Evidence based treatment of hallux valgus]. / Traitement de l'hallux valgus basé sur l'évidence.

Hallux valgus is a frequent disorder of the foot and decision-making about the best treatment provokes many questions among patients and specialists. These include the need for surgery, which surgical technique is the best choice, and is minimally invasive surgery going to replace open techniques? While the modern media provides patients with easy access to details concerning surgical techniques, they rarely include means for the patient to distinguish between objective information and publicity. The general practitioner is a person of trust for the patient and should help him or her consider treatment proposals. With these factors in mind, the aim of this paper is to share the evidence-based information regarding the treatment of hallux valgus with the general practitioner.

L'hallux valgus est une pathologie du pied fréquente et sa prise en charge suscite actuellement beaucoup de questions tant parmi les patients que parmi les experts. La chirurgie est-elle indispensable ? A quel moment faut-il opérer ? Quelle technique utiliser ? La chirurgie mini-invasive va-t-elle remplacer les techniques ouvertes ? Les médias modernes permettent aux patients un accès facile aux détails concernant les techniques chirurgicales existant sur le marché, sans pour autant leur donner des moyens de distinction entre l'information objective et la promotion. Le médecin traitant est un spécialiste de confiance vers lequel le patient doit pouvoir se tourner avant d'accepter une proposition thérapeutique. C'est pourquoi, et c'est le but de cet article, il nous paraît essentiel de partager la connaissance du traitement de l'hallux valgus basée sur l'évidence avec le médecin traitant.

Fixed and mobile-bearing total ankle prostheses: Effect on tibial bone strain.

BACKGROUND: Total ankle replacement is associated to a high revision rate. To improve implant survival, the potential advantage of prostheses with fixed bearing compared to mobile bearing is unclear. The objective of this study was to test the hypothesis that fixed and mobile bearing prostheses are associated with different biomechanical quantities typically associated to implant failure. METHODS: With a validated finite element model, we compared three cases: a prosthesis with a fixed bearing, a prosthesis with a mobile bearing in a centered position, and a prosthesis with mobile bearing in an eccentric position. Both prostheses were obtained from the same manufacturer. They were tested on seven tibias with maximum axial compression force during walking. We tested the hypothesis that there was a difference of bone strain, bone-implant interfacial stress, and bone support between the three cases. We also evaluated, for the three cases, the correlations between bone support, bone strain and bone-implant interfacial stress. FINDINGS: There were no statistically significant differences between the three cases. Overall, bone support was mainly trabecular, and less effective in the posterior side. Bone strain and bone-implant interfacial stress were strongly correlated to bone support. INTERPRETATIONS: Even if slight differences are observed between fixed and mobile bearing, it is not enough to put forward the superiority of one of these implants regarding their reaction to axial compression. When associated to the published clinical results, our study provides no argument to warn surgeons against the use of two-components fixed bearing implants.

Qualitative analysis of foot intersegment coordination in the sagittal plane following surgery for end-stage ankle osteoarthrosis.

Today, ankle joint kinematic assessment gives important information regarding the intersegment range of motion. It does not, however, provide information regarding coordination between the segments. This study aimed to determine whether or not intersegment coordination can provide valuable, otherwise missed information in relation to kinematic alterations of the ankle joint. The study consisted of 40 participants, including 12 total ankle replacement (TAR) patients, 12 ankle arthrodesis (AA) patients, and 16 controls. Gait assessment was carried out wearing 3-D inertial sensors. Intersegment coordination was determined by calculation of the continuous relative phase (CRP) between foot intersegments. CRP analysis found useful information regarding the magnitude and directionality of segment motion throughout the gait cycle, with AA patients reporting an altered coordination pattern for all three intersegments, forefoot-hindfoot, hindfoot-shank, and forefoot-shank, and TAR patients showing alterations in the hindfoot-shank intersegment. Results show that assessment of intersegment coordination can provide further information, otherwise overlooked by the general kinematic assessment, which could be used to optimize patient rehabilitation. Furthermore, the study showed that such information could be used to compare surgical outcomes. As a result, the study concludes that the inclusion of intersegment coordination assessment could be beneficial in clinical practice. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1304-1310, 2017.

Hallux valgus, ankle osteoarthrosis and adult acquired flatfoot deformity: a review of three common foot and ankle pathologies and their treatments.

The pathogenesis of hallux valgus deformity is multifactorial. Conservative treatment can alleviate pain but is unable to correct the deformity. Surgical treatment must be adapted to the type and severity of the deformity. Success of surgical treatment ranges from 80% to 95%, and complication rates range from 10% to 30%.Ankle osteoarthrosis most commonly occurs as a consequence of trauma. Ankle arthrodesis and total ankle replacement are the most common surgical treatments of end stage ankle osteoarthrosis. Both types of surgery result in similar clinical improvement at midterm; however, gait analysis has demonstrated the superiority of total ankle replacement over arthrodesis. More recently, conservative surgery (extraarticular alignment osteotomies) around the ankle has gained popularity in treating early- to mid-stage ankle osteoarthrosis.Adult acquired flatfoot deformity is a consequence of posterior tibial tendon dysfunction in 80% of cases. Classification is based upon the function of the tibialis posterior tendon, the reducibility of the deformity, and the condition of the ankle joint. Conservative treatment includes orthotics and eccentric muscle training. Functional surgery is indicated for treatment in the early stages. In case of fixed deformity, corrective and stabilising surgery is performed. Cite this article: Crevoisier X, Assal M, Stanekova K. Hallux valgus, ankle osteoarthrosis and adult acquired flatfoot deformity: a review of three common foot and ankle pathologies and their treatments. EFORT Open Rev 2016;1:58-64. DOI: 10.1302/2058-5241.1.000015.

Development and experimental validation of a finite element model of total ankle replacement.

Total ankle replacement remains a less satisfactory solution compared to other joint replacements. The goal of this study was to develop and validate a finite element model of total ankle replacement, for future testing of hypotheses related to clinical issues. To validate the finite element model, an experimental setup was specifically developed and applied on 8 cadaveric tibias. A non-cemented press fit tibial component of a mobile bearing prosthesis was inserted into the tibias. Two extreme anterior and posterior positions of the mobile bearing insert were considered, as well as a centered one. An axial force of 2kN was applied for each insert position. Strains were measured on the bone surface using digital image correlation. Tibias were CT scanned before implantation, after implantation, and after mechanical tests and removal of the prosthesis. The finite element model replicated the experimental setup. The first CT was used to build the geometry and evaluate the mechanical properties of the tibias. The second CT was used to set the implant position. The third CT was used to assess the bone-implant interface conditions. The coefficient of determination (R-squared) between the measured and predicted strains was 0.91. Predicted bone strains were maximal around the implant keel, especially at the anterior and posterior ends. The finite element model presented here is validated for future tests using more physiological loading conditions.

Outcome of unilateral ankle arthrodesis and total ankle replacement in terms of bilateral gait mechanics.

Previous studies assessed the outcome of ankle arthrodesis (AA) and total ankle replacement (TAR) surgeries; however, the extent of postoperative recovery towards bilateral gait mechanics (BGM) is unknown. We evaluated the outcome of the two surgeries at least 2 years post rehabilitation, focusing on BGM. 36 participants, including 12 AA patients, 12 TAR patients, and 12 controls were included. Gait assessment over 50 m distance was performed utilizing pressure insoles and 3D inertial sensors, following which an intraindividual comparison was performed. Most spatiotemporal and kinematic parameters in the TAR group were indicative of good gait symmetry, while the AA group presented significant differences. Plantar pressure symmetry among the AA group was also significantly distorted. Abnormality in biomechanical behavior of the AA unoperated, contralateral foot was observed. In summary, our results indicate an altered BGM in AA patients, whereas a relatively fully recovered BGM is observed in TAR patients, despite the quantitative differences in several parameters when compared to a healthy population. Our study supports a biomechanical assessment and rehabilitation of both operated and unoperated sides after major surgeries for ankle osteoarthrosis.