Ankle Foot Research Articles

Revisiting the anatomy of inferior extensor retinaculum of foot and ankle, a study based on fifty embalmed adult cadaveric lower extremities

BackgroundThe facial condensation of deep fascia form retinacula, Superior and Inferior, with a primary function to hold the extensor tendons of the foot in position. The morphology of inferior extensor retinaculum (IER) is clinically important in the tendon rupture repair and foot drop surgeries. The anatomy of ankle and foot IER is not much investigated and this prompted us to conceptualize this study to investigate the morphology and morphological variants of IER. MethodsThis descriptive, cross-sectional institutional based study included 50 dorsa of feet from the 25 embalmed adult cadavers. ResultsThe present study observed that, the anatomy of IER is complex wherein multiple septa of varied thickness arise from its undersurface from both the stem and limbs, defining its compartments. Five well defined compartments existed, which lodged the extensor tendons. The third compartment was deep and overlapped by the extensor digitorum longus tendons. Fourth compartment was well defined and lodged the extensor digitorum longus and peroneus tertius tendons, separated by an ill-defined septum. However, in 6 specimens (12%), the peroneus tertius traversed the fifth compartment, which otherwise did not have any contents. Some morphological variants of the tendons were also noted as they passed beneath the IER. ConclusionOur study is novel in determining the compartment format, deeper connections of IER, and relations with deeper structures along with the anatomical variations, which are clinically important in ankle arthroscopy, tendinoscopy, tendon repairs and foot drop stabilization surgeries.

Structural Characteristics according to the Design of a Custom Ankle Foot Orthoses

Structural Characteristics according to the Design of a Custom Ankle Foot Orthoses

The Kinetic and Kinematic Efficacy of Posterior Leaf Spring Ankle-foot Orthosis in Patients with Drop foot

Background: Dorsi flexor weakness is one of the common consequences of stroke with a negative impact on normal walking. Posterior leaf spring (PLS) Ankle Foot Orthosis (AFO) is the most frequent prescription to assist foot clearance and leg propulsion in these patients. However, the real efficacy of this AFO needs more attention. This study aimed to investigate the efficacy of PLS AFO on gait outcomes as the most common AFO in drop foot post-stroke patients. Methods: The study design was a pre–post-test experiments in which twenty drop foot patients with a mean age of 65 years with a mean age of 58.45 (±5.23) years who were 4/5 years post-stroke. They walked at self-selected walking speed on a 10 meters walk away in two conditions of with their own shoes and PLS AFO. The 3D motion capture gait analysis system including 6 vicon cameras and a Kistler force plate were used in order to measure gait kinetic and kinematic variables. For each trial, each joints (ankle, knee and hip) angle, moment and power were averaged over one-minute walking. Results: Walking with PLS showed a statistically significant improve kinetic and kinematic variables in hip, knee and ankle joints included power, moments and angles at entire gait cycle. P<0.05. Conclusions: In our study of stroke patients who were fitted with a PLS AFO, immediate significant improvements occurred in most kinetic and kinematic than shoes only in sacrifice some others.

Effect of Ankle Foot Orthosis (AFO) on kinematics in Children with Cerebral Palsy (CP)

Introduction: Children with cerebral palsy have impaired motor control, caused by prenatal and postnatal causes that affect the developing brain which leads to Muscle weakness, sensory loss, and stiffness Objective: To assess the efficacy of floor reaction orthoses (FRO) and solid ankle foot orthoses (AFO) with gait's temporospatial factors. Methodology: It was experimental based with custom molded Floor reaction orthosis and Solid ankle foot orthosis, the sampling technique was Non-probability Convenience sampling the targeted population was CP patients, and trials were taken from the patient. Results: FRAFO significantly improved patient cadence, velocity, stride time, stance, and swing phases compared to SAFO, with better improvement in kinetic dynamics and a decrease in stance and swing phases. Conclusion: FRAFO is more effective than SAFO.

On the Design of a Simulation-Assisted Human-Centered Quasi-Stiffness-Based Actuator for Ankle Orthosis

Most exoskeletons designed to assist users in load-bearing tasks face a mechanical dilemma in their conception. Designers may find a compromise between stiff active actuators-based architectures which are powerful but bulky and compliant actuator-based designs which are much less assistive but less constraining for users. This article presents a new open-source simulation-based design tool and a human-centered method that lets orthosis designers explore different device configurations and evaluate some performance criteria. This framework was applied in three different young-adult subjects. The effects of design personalization on user morphology and gait were studied. First, an ankle–foot orthosis designed to support a 20 kg backpack was defined according to the user’s height, weight, and walking speed. Then, a simulation of the subjects fitted with their customized design walking at a self-selected speed on flat ground carrying this additional load was performed. First, the results showed that the designed method inspired by natural joint stiffness behavior provided viable personalized mechanisms. Second, significant reductions in peak joint torque and mean joint activity were observed when comparing muscle-generated torques while the subject was wearing the 20 kg backpack with ankle–foot orthoses on both legs or without. Finally, it shows the value of an open-access tool for exploring the coupling of passive and active actuators to generate lighter and more compliant designs.

An expository analysis of biomechanical and subjective impacts induced by shoe inserts in asymptomatic subjects: A systematic review on functionality and mechanisms of action

AbstractThis systematic review explores the biomechanical and subjective effects of shoe inserts, including foot orthotics (FOs) and insoles, in asymptomatic subjects. Aimed at understanding their implications, the review poses two key research questions: (i) the influence of shoe inserts on lower extremity biomechanics and subjective perception and (ii) the effects of different design characteristics on these aspects. Following Preferred Reporting of Systematic Reviews and Meta‐Analysis guidelines, a meticulous search of Scopus and PubMed from August 2022 to March 2023 yielded 34 articles, with 26 focusing on biomechanical effects and eight on comfort effects. The studies, conducted during static and dynamic activities, such as standing, walking, jogging, running, jumping, and cycling, reveal significant reductions in rearfoot eversion, knee joint forces, and lower extremity muscle forces through postings and wedging in FOs. Changes in stiffness impact rearfoot kinematics, plantar pressure distribution, and ankle–foot power distribution. Conversely, surface texture and arch variations demonstrate limited significance. FOs and shoe inserts, characterized by geometric, material, location, size, and fabrication features, effectively regulate forces and moments on the lower extremity. This control promotes uniform plantar pressure distribution and enhances comfort during various activities. These insights benefit manufacturers, clinicians, and stakeholders, providing a deeper understanding of the positive benefits of FOs and shoe inserts. However, further well‐designed studies on clinical populations are necessary to validate these findings and establish their clinical efficacy, as the current focus remains on healthy subjects.

Rebuilding Stability: Exploring the Best Rehabilitation Methods for Chronic Ankle Instability.

Background: Chronic Ankle Instability (CAI) is a common condition characterized by repeated episodes of ankle "giving way" and impaired balance, leading to functional limitations. Various rehabilitation techniques, including balance training, proprioceptive exercises, whole-body vibration (WBV), and novel approaches like stroboscopic vision, are used to address these deficits. This review evaluates the effectiveness of different rehabilitation interventions for CAI management. Methods: A review was conducted by analyzing 11 randomized controlled trials that investigated the impact of balance and proprioceptive training programs on CAI. The primary outcomes assessed were the Star Excursion Balance Test (SEBT), Cumberland Ankle Instability Tool (CAIT), and Foot and Ankle Ability Measure (FAAM). Methodological quality was assessed using the PEDro scale, and the risk of bias was evaluated with the ROB 2 tool. Results: All rehabilitation interventions demonstrated significant improvements in SEBT, CAIT, and FAAM scores. However, no single intervention was found to be consistently superior. Traditional balance training, strength exercises, BAPS, and WBV all provided meaningful functional gains. Stroboscopic vision training showed similar effectiveness compared to conventional approaches. The evidence supports a combination of balance and strength training for optimal recovery. Conclusions: Balance and proprioceptive exercises are effective in managing CAI, with improvements in both dynamic stability and subjective outcomes. No intervention stands out as the best, but personalized programs incorporating various methods are recommended. Future research should explore the long-term effects and potential synergies of combined interventions.

Evaluation of the Working Mechanism of a Newly Developed Powered Ankle–Foot Orthosis

Ankle–foot orthoses (AFOs) are commonly prescribed to children with cerebral palsy (CP). The conventional AFO successfully controls the first and second ankle rocker, but it fails to correct the third ankle rocker, which negatively effects push-off power. The current study evaluated a new powered AFO (PAFO) design, developed to address the shortcomings of the conventional AFO. Eight children with spastic CP (12.4 ± 3.4 years; GMFCS I-III; 4/4-♂/♀; 3/5-bi/unilateral) were included. Sagittal kinematic and kinetic data were collected from 20 steps during barefoot walking, with conventional AFOs and PAFOs. In the PAFO-condition, an actuation unit was attached to a hinged AFO and through push–pull cables to a backpack that was carried by the child and provided patient-specific assistance-as-needed. SnPM-analysis indicated gait cycle sections that differed significantly between conditions. For the total group, differences between the three conditions were found in ankle kinematics (49.6–66.1%, p = 0.006; 88.0–100%, p = 0.011) and angular velocity (0.0–6.0%, p = 0.001; 45.1–51.1%, p = 0.006; 62.2–73.0%, p = 0.001; 81.2–93.0%, p = 0.001). Individual SnPM-analysis revealed a greater number of significant gait cycle sections for kinematics and kinetics of the ankle, knee, and hip. These individual results were heterogeneous and specific per gait pattern. In conclusion, the new PAFO improved the ankle range-of-motion, angular velocity, and power during push-off in comparison to the conventional AFO.

Development and design of a carbon fiber insole intended for individuals with partial foot amputation

Ankle and foot orthotics are suggested for gait rehabilitation therapy after a stroke. Clinical practice necessitates adjusting the ankle foot orthosis torque to accommodate each patient’s unique stride and body function. The objective of this paper is to develop a customized, cost-effective footplate orthosis from carbon fibers, manufactured using 3D printing, for individuals with partial foot amputations. The footplate is designed for use in developing nations and aimed to be made available with a reduced lead time. The experiment work carried out in this research is used to design, analyze, and validate a prosthetic footplate. A foot of size UK 7 with a 2 mm thick model of the human foot was modeled using Unigraphics-NX. The footplate’s design is being tested both conceptually and empirically. The footplate manufactured by applying load at toe and heel shows that the carbon fiber successfully restores leg length and reduces pressure on the feet’s delicate distal end.

A simple modified technique for screw fixation of displaced intra-articular calcaneus fracture through a sinus tarsi approach: a comparison with plate fixation

BackgroundPlates and screws are frequently used for the fixation of displaced intra-articular calcaneus fracture (DIACF). In this study, we compared the outcomes of a modified screw fixation technique with plate fixation via a sinus tarsi approach (STA).MethodsA series of 187 DIACF patients who were treated via an STA using a plate fixation (n = 81) or a screw fixation (n = 106) were included. Screw fixation was done with two 2.7 mm screws and two 6.5 mm cannulated screws. Outcomes were evaluated radiographically and clinically. Clinical evaluations included pain assessment by Visual Analogue Scale (VAS) and functional assessment by the American Orthopaedic Foot and Ankle Society (AOFAS) questionnaire and Foot Function Index (FFI).ResultsThe mean final VAS was smaller in the screw group (P = 0.01). The mean AOFAS and FFI scores were not significantly different between the two groups (P = 0.17 and P = 0. 19, respectively). The mean improvement of Bohler’s angle, but not the Gissane’s angle, was significantly greater in the screw group (P = 0.014 and P = 0.09, respectively). The mean improvement of calcaneal length and height were not significantly different between the two groups (P = 0.78 and P = 0.22, respectively). The hardware removal rate was 14.8% in the plate group and 3.8% in the screw group (P = 0.007).ConclusionThe modified screw fixation method provides lower pain, better radiographic outcome, and lower rate of hardware removal compared to plate fixation in the treatment of DIACF.

The efficacy of the Novel Hybrid Passive Spring Damper Ankle Foot Orthosis regard to kinetic and kinematic parameters of patients with Multiple Sclerosis: An intervention study

ABSTRACT Drop foot is a common consequence of Multiple Sclerosis (MS), which may be improved somewhat by an ankle-foot orthosis (AFO). This study aimed to examine the immediate effect of using the recently developed Novel Hybrid Passive Spring Damper AFO (the novel HPSDAFO) on the kinetic and kinematic parameters of patients with MS (PwMS) in the sagittal plane. Twelve PwMS who suffered a unilateral drop foot participated in this study and fitted with the novel HPSDAFO. They walked with the novel HPSDAFO on the affected side and shoe on the affected side at a self-selected speed. Walking by the novel HPSDAFO, the symmetry of all of the evaluated sagittal kinetic and kinematic parameters improved noticeably. The range of ankle plantarflexion and knee flexion increased significantly at the stance phase. Power generation increased at all three joints. The peak of ankle dorsiflexion at early stances and the first peak of knee extension moments increased significantly but decreased at the hip joint. Changes in sagittal ROM, moment, and power generation in the plane and the improved symmetry revealed a more normal walking by using the novel HPSDAFO on the affected limb of PwMS.

A Descriptive Study on Assessment of Functional Status in Cerebral Palsy Patients Using Knee Ankle Foot Orthosis

A Descriptive Study on Assessment of Functional Status in Cerebral Palsy Patients Using Knee Ankle Foot Orthosis

Lateral ligament reconstruction and additive medial ligament reconstruction in chronic ankle instability: a retrospective study.

Ligamentous lesions of the ankle joint are common. Isolated medial ligament injuries are rare but are often associated with lateral ligament injuries, isolated medial ligament lesions are often overlooked. The present study aimed to evaluate the clinical and functional differences in the outcomes of isolated lateral and combined medial and lateral ligament reconstruction. The study is based on patient-reported outcome measurements and motion sensor technology to assess these outcomes. The purpose of this study was to compare the clinical and functional outcomes of isolated lateral and combined lateral and medial ankle ligament reconstruction. From December 2014 to August 2018, 111 patients underwent either isolated lateral ligament (LG) or medial and lateral ligament (MLG) reconstruction. Of the 104 patients meeting the inclusion criteria, 49 had LG and 55 had MLG reconstruction. Outcome measures included the Short Form-36 Health Survey SF-36, Foot and Ankle Outcome Score (FAOS), Foot and Ankle Ability Measure (FAAMG), Tegner Activity Scale, the European Foot and Ankle Society (EFAS), American Orthopaedic Foot and Ancle Society (AOFAS) hindfoot score, and the Karlsson Peterson Score. Mobility and stability were assessed using the Ortheligent™ motion sensor for both healthy and treated ankles. While there were no significant differences in outcome scores between the groups, overall scores improved after treatment (p >0.00). Notably LG showed improved movement, with better dorsal extension measured by the Sensor (p ÷ 0.02). The sensor's results correlated significantly with FAOS subscales for pain (p ÷0.05), stiffness (p ÷ 0.01), ADL (p ÷0.02), and sports (p >0.00). Postoperative results, regardless of LG or MLG, showed significant subjective well-being improvement. LG's advantages were highlighted by a significant improvement in dorsal extension, supported by correlated results from a portable motion sensor assessing ankle stability.

The Influence of Ankle Mobility and Foot Stability on Jumping Ability and Landing Mechanics: A Cross-Sectional Study.

Practicing physical activities or sports that involve frequent jumping and landing can strain the muscles and joints of the lower limbs, especially in those who do not have adequate physical preparation. The objective of this study was to (a) determine the correlation between ankle range of motion (ROM) and landing stability following jumps; (b) assess the association between the jump height in a counter-movement jump (CMJ) test and ankle ROM; and (c) examine the connection between stabilometry during specific jumps movements present in many sports and in ankle stabilization. Sixty-two healthy amateur volleyball players participated in the study (age: thirty-seven females and twenty-five males; age (years): 16.5 ± 4.25; height (cm): 166 ± 11.4; weight (Kg): 61.6 ± 13.7). Participants were recruited for the study in collaboration with student sports associations. The evaluations encompassed the measurement of ankle joint mobility for both lower limbs using an inertial sensor, a static baropodometric and stabilometric analysis using a pressure platform, and the CMJ test using the Microgate system. After the assessments, participants performed a "specific jump landing task". Significant correlations were found between foot range of motion (ROM) and counter-movement jump (CMJ) performance. Specifically, the ROM of the right foot had a strong correlation with the CMJ (r = 0.81, p < 0.001), while the left foot ROM showed a moderate correlation (r = 0.46, p < 0.001). The specific jump task revealed substantial changes in stabilometry parameters, particularly during forward hops compared to lateral jumps. Dorsiflexion ROM significantly impacts jumping ability. Evaluating landing patterns and stabilometry during targeted activities can help optimize training, improve dynamic balance, and reduce ankle injury risk.

Effects of ankle joint degree of freedom of knee–ankle–foot orthoses on loading patterns and triceps surae muscle activity on the paretic side in individuals with subacute severe hemiplegia: a retrospective study

BackgroundIndividuals with subacute severe hemiplegia often undergo alternate gait training to overcome challenges in achieving walking independence. However, the ankle joint setting in a knee–ankle–foot orthosis (KAFO) depends on trunk function or paralysis stage for alternate gait training with a KAFO. The optimal degree of ankle joint freedom in a KAFO and the specific ankle joint conditions for effective rehabilitation remain unclear. Therefore, this study aimed to investigate the effects of different degrees of freedom of the ankle joint on center-of-pressure (CoP) parameters and muscle activity on the paretic side using a KAFO and to investigate the recommended setting of ankle joint angle in a KAFO depending on physical function.MethodsThis study included 14 participants with subacute stroke (67.4 ± 13.3 years). The CoP parameters and muscle activity of the gastrocnemius lateralis (GCL) and soleus muscles were compared using a linear mixed model (LMM) under two ankle joint conditions in the KAFO: fixed at 0° and free ankle dorsiflexion. We confirmed the relationship between changes in CoP parameters or muscle activity under different conditions and physical functional characteristics such as the Fugl–Meyer Assessment of Lower Extremity Synergy Score (FMAs) and Trunk Impairment Scale (TIS) using LMM.ResultsAnterior–posterior displacement of CoP (AP_CoP) (p = 0.011) and muscle activity of the GCL (p = 0.043) increased in the free condition of ankle dorsiflexion compared with that in the fixed condition. The FMAs (p = 0.004) and TIS (p = 0.008) demonstrated a positive relationship with AP_CoP. A positive relationship was also found between TIS and the percentage of medial forefoot loading time in the CoP (p < 0.001).ConclusionsFor individuals with severe subacute hemiplegia, the ankle dorsiflexion induction in the KAFO, which did not impede the forward tilt of the shank, promotes anterior movement in the CoP and muscle activity of the GCL. This study suggests that adjusting the dorsiflexion mobility of the ankle joint in the KAFO according to improvement in physical function promotes loading of the CoP to the medial forefoot.

Practices in providing Ankle Foot Orthoses to Children with Cerebral Palsy in Norway

Practices in providing Ankle Foot Orthoses to Children with Cerebral Palsy in Norway

A predictive simulation study to assess the effect of ankle foot orthosis stiffness on balance recovery after tripping

A predictive simulation study to assess the effect of ankle foot orthosis stiffness on balance recovery after tripping

Prediction of the optimal ankle foot orthosis stiffness using peak ankle moment when walking on shoes-only in neuromuscular diseases

Prediction of the optimal ankle foot orthosis stiffness using peak ankle moment when walking on shoes-only in neuromuscular diseases

Repeatability of gait of children with spastic cerebral palsy in different walking conditions

Three-dimensional gait analysis is the ‘gold standard’ for measurement and description of gait. Gait variability can arise from intrinsic and extrinsic factors and may vary between walking conditions. This study aimed to define the inter-trial and inter-session repeatability in gait analysis data of children with cerebral palsy (CP) who were walking in four conditions, namely barefoot or with ankle–foot orthosis (AFO), and overground or treadmill. Ten children with spastic CP (7♀; 9.9y ± 3.5y; GMFCS-level I-III) were included in this study. Overall, we found good to excellent intra-class correlation (ICC)-values and favourable standard error of measurement (SEM)-values for the inter-session Gait Profile Score (ICC = 0.85–0.98, SEM = 0.45–0.91°) and Gait Variable Scores (ICC = 0.85–0.99, SEM = 0.22–1.11°) for the lower-limb joints. Taking the total joint-range-of-motion into account, the knee joint showed the most repeatable motion (%SEM = 0.5–1.8 %), while ankle motions showed the lowest repeatability (%SEM = 0.8 %–3.0 %). For the continuous waveform data, only the ankle joint showed repeatability differences between walking conditions, namely, smaller SEM-values for the AFO-condition (mean inter-trial = 0.14°; mean inter-session = 1.121°) in comparison to the barefoot-condition (mean inter-trial = 0.55°; mean inter-session = 2.22°). For all the kinetic parameters, the treadmill conditions showed smaller SEM-values in comparison to the overground condition. In conclusion three-dimensional gait analysis was found to be reliable in all four walking conditions for children with CP. The resulting measurement errors can be used as a reference during clinical interpretations of gait analyses.Clinical trial registration number: Trial ID from an internationally recognized trial registry (ClinicalTrials.gov): NCT06355869

Effects of carbon versus plastic ankle foot orthoses on gait outcomes and energy cost in patients with chronic stroke.

To compare the walking performances of hemiplegic subjects with chronic stroke under 3 conditions: with a new standard carbon fibre ankle foot orthosis (C-AFO), with a personal custom-made plastic AFO (P-AFO), and without any orthosis (No-AFO). Randomized, controlled crossover design. Fifteen chronic patients with stroke (3 women and 12 men, 59 [10] years, 13 [15] years since injury). Patients performed 3 randomized sessions (with C-AFO, P-AFO, no-AFO), consisting of a 6-min walk test (6MWT) with VO2 measurement and a clinical gait analysis. Energy cost (Cw), walking speed, spatio-temporal, kinetic, and kinematic variables were measured. No significant differences were found between the C-AFO and P-AFO conditions. Distance and walking speed in the 6MWT increased by 12% and 10% (p < 0.001) and stride width decreased by -8.7% and -13% (p < 0.0001) with P-AFO and C-AFO compared with the No-AFO condition. Cw decreased by 15% (p < 0.002), stride length increased by 10% (p < 0.01), step length on affected leg increased by 8% (p < 0.01), step length on contralateral leg by 13% (p < 0.01), and swing time on the contralateral leg increased by 6% (p < 0.01) with both AFO compared with the No-AFO condition. The use of an off-the-shelf composite AFO (after a short habituation period) in patients with chronic stroke immediately improved energy cost and gait outcomes to the same extent as their usual custom-made AFO.