Gastrocnemius electrical stimulation increases ankle dorsiflexion strength in patients with post-acute sequelae of SARS-COV-2 (PASC): a double-blind randomized controlled trial.

Post-Acute sequelae of SARS-CoV-2 (PASC) is a multisystem disorder causing persistent musculoskeletal deconditioning and reduced lower extremity strength. Electrical stimulation (E-Stim) to the gastrocnemius muscle can enhance strength outcomes by increasing the frequency of muscle fiber activation. We investigated its effect on individuals with PASC. Participants were randomized into intervention (IG) or control (CG) groups. The IG self-administered daily one-hour E-Stim to both their gastrocnemius muscles using a functional device over 4-week, while the CG used a sham device. Primary outcomes were ankle dorsiflexion strength assessed via dynamometry during maximum voluntary contractions, and gastrocnemius voluntary activation (GVA) via surface electromyography. The secondary outcome assessed activities of daily living (ADL), instrumental ADL, and mobility queries. Percentage improvement was calculated. Eighteen patients were analyzed (IG = 10; CG = 8). After 4 week, the IG showed a significantly higher improvement in ankle dorsiflexion strength (222.64%) compared to the CG (51.27%, p = 0.002). Additionally, the IG's ankle dorsiflexion strength improvement significantly correlated with GVA improvement (rho = 0.782) at 4 week. The secondary outcomes did not reveal significant changes in neither group. Self-administered gastrocnemius E-Stim improves ankle dorsiflexion strength in individuals with PASC. However, larger sample sizes and longer interventions are needed to validate these findings.

Effects of shoe heel height on ankle dynamics in running.

Shoes affect the evolved biomechanics of the foot, potentially affecting running kinematics and kinetics that can in turn influence injury and performance. An important feature of conventional running shoes is heel height, whose effects on foot and ankle biomechanics remain understudied. Here, we investigate the effects of 6-26 mm increases in heel height on ankle dynamics in 8 rearfoot strike runners who ran barefoot and in minimal shoes with added heels. We predicted higher heels would lead to greater frontal plane ankle torques due to the increased vertical moment arm of the mediolateral ground reaction force. Surprisingly, the torque increased in minimal shoes with no heel elevation, but then decreased with further increases in heel height due to changes in foot posture. We also found that increasing heel height caused a large increase in the ankle plantarflexion velocity at heel strike, which we explain using a passive collision model. Our results highlight how running in minimal shoes may be significantly different from barefoot running due to complex interactions between proprioception and biomechanics that also permit runners to compensate for modifications to shoe design, more in the frontal than sagittal planes.

The effect of vibration-hinged ankle foot orthoses on gait and spasticity in children with cerebral palsy: A randomized clinical trial design.

BACKGROUND: Hinged ankle foot orthoses (HAFO) are commonly prescribed for children with cerebral palsy (CP) to improve their ambulatory function. OBJECTIVES: The aim of this study was to compare the effect of vibration-HAFO with that of the same orthosis without vibration on gait, function, and spasticity in hemiplegic CP children. STUDY DESIGN: Randomized Control Trial Design (a pilot study). METHODS: Twenty-three children with hemiplegic CP participated in this study. The control group (n = 12) used HAFO, and the intervention group (n = 11) used vibration-HAFO for four weeks. Pre-post three-dimensional gait analysis was done. Calf muscle spasticity and function were also measured. RESULTS: Results showed significant differences between the two groups in the one-minute walking test (p = 0.023) and spasticity (after intervention [p = 0.022], after follow-up [p = 0.020]). Also, significant differences were detected between the two groups in the step width (p = 0.042), maximum hip abduction (p = 0.008), stance maximum dorsiflexion (p = 0.036) and mean pelvic tilt (p = 0.004) in the barefoot condition. Gait cycle time (p = 0.005), maximum hip abduction (p = 0.042), and cadence (p = 0.001) were different between groups in the braced condition. We couldn't find any significant within and between groups differences in knee kinematic parameters. The mean time of using vibration was 16.83 minutes per day. CONCLUSIONS: The vibration-hinged AFO is feasible, safe, and acceptable for children with hemiplegic CP to be integrated into practice. Temporospatial and clinical parameters, especially spasticity, were improved. There were slight trends toward improvement in pelvic and knee kinematics. Vibration-HAFO is of benefit to ambulatory CP children with mild and moderate spasticity. It improved the walking capacity of the children.

Biomechanics of step-off drop landings are affected by limb dominance and lead limb in task initiation.

This study examines the effects of limb dominance and lead limb in task initiation on the kinetics and kinematics of step-off drop landings. Nineteen male participants performed drop landings led by the dominant and non-dominant limbs at 45-cm and 60-cm drop heights. Ground reaction force (GRF) and lower body kinematic data were collected. Between-limb time differences at the initial ground contact were calculated to indicate temporal asymmetry. Statistical Parametric Mapping (SPM) was applied for waveform analysis while two-way repeated measures ANOVA was used for discrete parameters. SPM results revealed greater GRF and lesser ankle dorsiflexion in the lead limb compared to the trail limb in 3 out of 4 landing conditions. The dominant limb displayed a greater forefoot loading rate (45 cm: p=.009, ηp2 = 0.438; 60 cm: p=.035, ηp2 = 0.225) and greater ankle joint quasi-stiffness (45 cm: p < .001, ηp2 = 0.360; 60 cm: p < .001, ηp2 = 0.597) than the non-dominant limb. Not all 380 trials were lead-limb first landings, with a smaller between-limb time difference (p=.009, d = 0.60) at 60 cm (4.1 ± 2.3 ms) than 45 cm (5.6 ± 2.7 ms). In conclusion, the step-off drop landing is not an ideal protocol for examining bilateral asymmetry in lower limb biomechanics due to potential biases introduced by limb dominance and the step-off limb.

A biomechanical study comparing the compression force and osseous area of contact of two screws fixation techniques used in ankle joint arthrodesis model.

INTRODUCTION: Arthrodesis of a (diseased) ankle joint is usually performed to achieve pain relief and stability. One basic principle of arthrodesis techniques includes rigid fixation of the surfaces until union. It seems plausible that stable anchoring and homogeneous pressure distribution should be advantageous, however, it has not been investigated yet. The aim is to achieve uniform compression, as this is expected to produce favorable results for the bony fusion of the intended arthrodesis. Numerous implants with different biomechanical concepts can be used for ankle fusion. In this study, headless compression screws (HCS, DePuy Synthes, Zuchwil, Switzerland) were compared biomechanically to an alternative fixation System, the IOFix device (Extremity Medical, Parsippany, NJ, USA) in regard to the distribution of the compression force (area of contact) and peak compression in a sawbone arthrodesis-model (Sawbones® Pacific Research Laboratories, Vashon, WA, USA). This study aims to quantify the area of contact between the bone interface that can be obtained using headless compression screws compared to the IOFix. In current literature, it is assumed, that a large contact surface with sufficient pressure between the bones brings good clinical results. However, there are no clinical or biomechanical studies, that describe the optimal compression pressure for an arthrodesis. MATERIAL AND METHODS: Two standardized sawbone blocks were placed above each other in a custom-made jig. IOFix and headless compression screws were inserted pairwise parallel to each other using a template for a uniform drilling pattern. All screws were inserted with a predefined torque of 0.5 Nm. Pressure transducers positioned between the two sawbone blocks were compressed for the measurement of peak compression force, compression distribution, and area of contact. RESULTS: With the IOFix, the compression force was distributed over significantly larger areas compared to the contact area of the HCS screws, resulting in a more homogenous contact area over the entire arthrodesis surface. Maximum compression force showed no significant difference. CONCLUSION: The IOFix system distributes the compression pressure over a much larger area, resulting in more evenly spread compression at the surface. Clinical studies must show whether this leads to a lower pseudarthrosis rate.

Effects of high tibial osteotomy on the coronal, sagittal, and axial alignments of the ankle joint.

BACKGROUND: No comprehensive study has been conducted on the effects of high tibial osteotomy (HTO) on the coronal, sagittal, and axial alignments of the ankle joint. Therefore, this study aimed to investigate the multiplane changes in the ankle joint following HTO using the EOS biplanar X-ray imaging system. METHODS: The medical records of 43 patients who underwent HTO for the treatment of medial knee osteoarthritis were retrospectively reviewed. Preoperative and postoperative EOS images and lower-extremity scanograms were evaluated; the correlations between the outcomes were evaluated. RESULTS: After HTO, the ankle joint axis point on the weight-bearing line showed significant lateralization (p < .001). The knee lateral ankle surface angle increased significantly in the sagittal alignment (p < .001). The distal tibia showed a significant internal rotation in the axial plane (p = .022). Tibial rotation showed no significant relationship with the other parameters. CONCLUSIONS: HTO induced lateralization of the ankle joint axis (coronal), increased the posterior tibial slope (sagittal), and caused the internal rotation of the distal tibia (axial). Axial changes in the distal tibia showed no significant relationship with other coronal and sagittal parameters of the ankle joint. We suggest that surgeons should consider, during HTO, that the ankle joint axis shifts laterally and distal tibia has tendency to rotate internally after HTO.

How boots affect the kinematics and kinetics of lower limb joints during walking compared to casual footwear.

Boots are widely used by many people for various purposes, but their impact on gait biomechanics and injury risk is not well understood. This study investigated the effects of boots on walking biomechanics, compared to casual footwear. The lower limb joint kinematics and kinetics of 20 healthy male participants aged 20 to 30 years old were compared during self-paced walking with boots and shoes. The results showed that walking with boots is associated with greater hip extensor (P = 0.009) and ankle dorsiflexor (P < 0.001) moments in early stance, hip power generation (P < 0.001) and knee power absorption (P < 0.001) in early swing phase, hip abductor (P < 0.001) and knee adduction (P < 0.001) moments in the entire stance, net concentric work for the hip joint in sagittal (13.9%, P = 0.001) and frontal (21.7%, P = 0.002) planes. In contrast, the subtalar supinator moment in the entire stance (P < 0.001), ankle angular velocity in late stance (P < 0.001), and net concentric (- 42.7%, P < 0.001) and eccentric (- 44.6%, P = 0.004) works of subtalar joint were significantly lower in the boot condition. The compensatory adjustments in the hip and knee joints may result from ankle restrictions. While boots may aid those with ankle disorders, lower limb loading and the risk of musculoskeletal injuries and osteoarthritis could be increased. This study offers new perspectives on the biomechanical impact of boots on gait, potential prevention and treatment strategies of related injuries, and advancing footwear design.

Effect of a semirigid ankle brace on the in vivo kinematics and muscle activity of patients with functional ankle instability during simulated ankle sprain.

INTRODUCTION: Ankle braces can effectively decrease the incidence of recurrent ankle sprain; however, whether the brace can decrease the severity of sprain and its related mechanism during sprain remain unknown. METHODS: Twenty-two patients with functional ankle instability (FAI) (12 males and 10 females) and 16 healthy subjects (8 males and 8 females) were enrolled in this study. All of the subjects walked on a custom-built tilting platform that offered a 30° inversion (IV) to mimic the IV of ankle sprain. We collected the kinematic and surface electromyography data of patients with FAI with or without ankle brace and normal controls 6 times. RESULTS: The FAI without brace group showed significantly higher maximum IV angles and average IV velocities than the control group (P < .001). The FAI with brace group revealed significantly lower maximum IV angles and average IV velocities than the FAI without brace group (P < .001); this group also showed significantly higher maximum external rotation (ER) angle and average ER velocities than the FAI with brace (P < .001) and control (P < .001) groups. The FAI with brace group indicated significantly lower average EMGPrep (P = .047), EMGTilt (P = .037), and EMGafterTilt (P = .004) of the peroneus longus than the FAI without brace group. CONCLUSIONS: The ankle brace could effectively decrease IV angles and their velocities and increase ER angles and their corresponding velocities during ankle sprain in patients with FAI. It could also decrease the activity of the peroneus longus muscle during ankle sprain.

The effect of joint mobilization of Maitland on chronic ankle instability: A randomized trial.

BACKGROUND: The aim of study was to observe the therapeutic effect of joint mobilization of Maitland on subjects with chronic ankle instability (CAI). METHODS: 76 subjects with CAI were recruited for this randomized, single-blinded trial and randomized divided into experimental group (EG) and control group (CG). The CG was received conventional rehabilitation, and the EG added 8-weeks treatment of Maitland technology based on the CG. The visual analogue scale, ankle range of motion, Y-balance test, and Foot and Ankle Ability Measure scores (the daily living part of Foot and Ankle Ability Measure scores and the sport part of Foot and Ankle Ability Measure scores) were measured before and 8 weeks after the intervention respectively. RESULTS: There was no significant difference on outcomes between the 2 groups before treatment (P > .05). After 8 weeks of intervention, the visual analogue scale, ankle range of motion (dorsiflexion, plantar flexion, and varus), the value of Y-balance test (forward extension distance, inner extension distance, and posterior extension distance), the daily living part of Foot and Ankle Ability Measure scores, and the sport part of Foot and Ankle Ability Measure scores of the 2 groups were significantly improved (P < .01), and the improvement of the EG showed remarkable than CG (P < .01). CONCLUSION: Maitland therapy is effective in the treatment of CAI. Conventional rehabilitation assisted by Maitland therapy were beneficial to improve pain and functional state in patients with CAI than only routine rehabilitation.

Effects of ankle Kinesio taping on knee and ankle joint biomechanics during unanticipated jumps in collegiate athletes.

OBJECTIVE: Most biomechanical research on the application of Kinesio taping (KT) to the ankle joint focused on testing anticipated movements. However, ankle sprains frequently occur in real life in unanticipated situations, where individuals are unprepared and face sudden external stimuli. This situation is completely different from the anticipated situation. The aim of the present study was to investigate the effects of ankle KT application on the kinematic and kinetic characteristics of the knee and ankle joints during unanticipated jump tasks in collegiate athletes. METHODS: Eighteen healthy collegiate athletes experienced three taping conditions in a randomized order: no taping (NT), placebo taping (PT), and KT, and performed unanticipated jump tasks. A 9-camera infrared high-speed motion capture system was employed to collect knee and ankle kinematic data, and a 3-dimensional force plate was utilized to collect knee and ankle kinetic data during the tasks. RESULTS: During the right jumps, KT significantly increased peak knee flexion angle (P = 0.031) compared to NT and significantly decreased peak vertical ground reaction force (P < 0.001, P = 0.001) compared to NT and PT. During the left jumps, KT significantly reduced peak ankle inversion angle (P = 0.022, P < 0.001) and peak ankle inversion moment (P = 0.002, P = 0.001) compared to NT and PT. CONCLUSION: During unanticipated jump maneuvers, KT reduced peak ankle inversion angle, peak vertical ground reaction force, and peak ankle inversion moment and increased peak knee flexion angle in collegiate athletes.

A Novel Approach to Total Ankle Arthroplasty with Simultaneous Structural Tibial Cut Autograft for Anterior Tibial Bone Defects.

Severe bone defects pose a clinical challenge in total ankle arthroplasty (TAA) and are frequently considered contraindicated. We introduce an innovative approach that utilizes a structural tibial cut autograft to address anterior distal tibia bone defects during TAA. This technique is a viable alternative to employing revision TAA systems or resorting to excessively high tibial cuts. Furthermore, it facilitates achieving favorable sagittal alignment and ensures adequate fixation strength of the tibial component.

Comparison of Midterm Outcomes between All-Inside Arthroscopic and Open Modified Broström Procedures as Treatment for Chronic Ankle Instability.

Background: Although the all-inside arthroscopic modified Broström operation (AMBO) and open modified Broström operation (OMBO) for chronic lateral ankle instability (CLAI) showed favorable outcomes up to 1-year short-term follow-up, concerns about the long-term stability of AMBO are still present. Therefore, we aimed to compare midterm outcomes between the 2 methods by extending the observation period. Methods: Fifty-four patients undergoing ankle surgery between August 2013 and July 2017 were included in the AMBO (n = 37) and OMBO (n = 17) groups. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale and a visual analog scale (VAS) were used to evaluate the clinical outcomes. Anterior drawer test and talar tilt angle were used to evaluate the radiological outcomes. The mean follow-up duration was 59.69 months. Results: The 2 groups both showed improved clinical and radiological results statistically. In addition, they did not differ in age, sex, or preoperative AOFAS ankle-hindfoot scale score, VAS score, anterior drawer test, or talar tilt angle. No significant difference in the final follow-up postoperative clinical scores or radiological outcomes was observed. Conclusions: AMBO and OMBO as treatments for CLAI did not yield differing clinical or radiological outcomes at a mean follow-up time point of 59.69 months.

Midterm Results after Tibiotalar or Tibiotalocalcaneal Fusion Using an Ilizarov External Fixator.

Background: Ankle fusion is considered a treatment of choice for end-stage ankle arthritis when a total ankle replacement procedure is not indicated. However, the potential risk of secondary arthritis in the adjacent joint after ankle fusion raises arguments on whether preserving the adjacent joint during an isolated tibiotalar (TT) fusion brings about any future benefits with regard to pain and gait discomfort. In this study, we intended to present midterm results following TT or tibiotalocalcaneal (TTC) fusion using an Ilizarov external fixator and to investigate whether spontaneous fusion occurred in the subtalar or midtarsal joint. Methods: This is a retrospective observational study. Medical records of patients who underwent TT or TTC fusion using an Ilizarov external fixator for substantial bone defects around the ankle joint between 1994 and 2018 were manually searched. Forty-one patients were included and the status of the joints adjacent to the fusion site was evaluated in radiographic examinations. Results: Of the 34 patients who underwent TT fusion, 30 patients (88.3%) had a spontaneous fusion in the adjacent joints. Specifically, 11 patients (29.4%) had subtalar joint fusion and 19 patients (55.9%) had both midtarsal joint and subtalar joint fusion. In TTC fusion, the midtarsal joint was spontaneously fused in all 7 patients. Conclusions: In this study, we observed spontaneous adjacent joint fusion following TT or TTC fusion using an Ilizarov external fixator for substantial bone defects around the ankle joint. Although a careful approach should be made since patients treated in this study may not represent typical candidates that need primary joint-sacrificing procedures, we believe that this study may draw attention from surgeons concerned about the fate of the adjacent joint status after TT or TTC fusion.

Clinical and radiological outcomes of ankle joint preserving surgical reconstruction for talar neck non-unions-A series of 8 cases.

BACKGROUND: Talar neck non-unions result in significant hindfoot deformity and morbidity and are infrequently reported in the literature. The optimal surgical management for this condition is evolving, with various authors reporting the results of open reduction and internal fixation (ORIF) with bone grafting (BG), ankle fusion and modified Blair fusion. We performed this study to report the clinical and radiological outcomes of a cohort of talar neck non-unions managed by ankle joint preserving reconstruction. METHODS: This was an ambispective study which included 8 patients (7 male and 1 female) with talar neck non-unions. All patients underwent ORIF+BG through dual approaches. Additional medial malleolar osteotomy was done in 2 cases, and calcaneofibular split approach to the subtalar joint in 3. Adjunct subtalar fusion was done in 5 cases. Clinical and radiological evaluation was performed pre- and post-operatively. Functional outcomes were assessed by the Manchester Oxford Foot Questionnaire (MOxFQ). RESULTS: The mean age of patients 32.3 ± 13.1 years. The mean surgical delay was 4.1 ± 1.7 months. As per Zwipp and Rammelt classification of post-traumatic talar deformities, 5 cases were classified as Type 3, 2 were Type 4, and 1 was Type 1. Union was achieved in 7 cases at a mean of 3.4 ± 1.3 months. One case had progressive collapse, which was managed by pantalar arthrodesis. All 3 cases where subtalar fusion was not performed primarily demonstrated subtalar arthrosis, but none required a secondary subtalar fusion. The MOxFQ score from 61.1 ± 10.1 to 41 ± 14.1 postoperatively (P = 0.005). The mean follow-up was 14.6 ± 6.8 months. CONCLUSION: ORIF+BG of the talar neck, with or without subtalar fusion has the potential to achieve solid union, correct the hindfoot deformity and improve functional outcomes. However, larger studies with longer follow-up are needed to evaluate the long-term efficacy of this procedure.

Open total talus dislocation without concomitant malleoli fracture: a case report.

BACKGROUND: Total talus dislocation without ankle (malleoli) fracture is a very rare injury with prevalence of only 0.06% of all dislocations and only 2% of talar injuries, and are usually associated with common complications such as infection, avascular necrosis, and posttraumatic arthritis. The treatment usually involves debridement, reduction, stabilization of the ankle joint, and primary or secondary closure of the wound. CASE PRESENTATION: We present the case of a 40-year-old South Asian woman who was involved in an accident. She was rushed to our hospital, whereby subsequent examination revealed an open total talus dislocation with the talus being exposed in its entirety from a contaminated wound in the medial side. Furthermore, radiograph confirmed total talus dislocation without concomitant malleoli fracture. She was immediately taken to the operating theater whereby debridement and immediate reduction was performed under anesthesia, and the ankle was stabilized with external fixator for about 6 weeks. She is now able to bear weight on the affected ankle with minimal tolerable pain and has normal range of motion of the ankle. CONCLUSIONS: Open total talus dislocation without concomitant malleoli fracture is a rare injury. Reduction of the talus in combination with complete wound debridement potentially successfully avoids infection, provides early revascularization preventing avascular necrosis, and preserves the normal ankle anatomy.

Correlation of Posterior Tibial Tendon Ultrasound with Calcaneal Inclination Angle in Indonesian Professional Athletes with Medial Ankle Pain.

Background: Adult-acquired flatfoot deformity (AAFD) is characterized by partial or complete flattening of the longitudinal medial arch, which develops after maturity. AAFD secondary to posterior tibialis tendon dysfunction (PTTD) is one of professional athletes' most common foot and ankle pathologies. Different modalities and procedures can be used to establish the diagnosis of AAFD and PTTD. However, imaging measurements such as the calcaneal inclination index and ultrasonography (US) of the posterior tibialis tendon (PTT) in professional athletes with medial ankle and focal pain along the PTT have yet to be widely studied. This study investigates the correlation of PTT ultrasound for evaluating PTTD with calcaneal inclination angle (CIA) for evaluating AAFD in professional athletes with medial ankle and focal pain along the PTT. Through this study, clinicians and radiologists may benefit from considering AAFD in athletes with PTTD. Methods: 112 Indonesian professional athletes with medial ankle or foot pain and focal pain along the direction of the PTT underwent foot radiography using the CIA and ankle ultrasound to observe PTT abnormalities. Results: A negative correlation between fluid thickness surrounding the PTT and the CIA (p<0.001; 95% CI - 0.945, - 0.885), as well as a negative correlation between PTT thickness and CIA (p<0.001, 95% CI - 0.926, - 0.845), with a correlation coefficient (r) of - 0.921 and - 0.892, respectively. No significant correlation was found between PTT tear and CIA (p = 0.728; 95% CI -0.223, - 0.159; r - 0.033). Conclusion: This study showed a negative correlation between PTTD and AAFD via ultrasound and CIA in professional athletes with medial ankle and focal pain along the PTT. A better understanding of PTTD and AAFD imaging will lead to more effective management and prompt treatment.

How Humans Run Faster: The Neuromechanical Contributions of Functional Muscle Groups to Running at Different Speeds.

How the neuromechanics of the lower limb functional muscle groups change with running speed remains to be fully elucidated, with implications for our understanding of human locomotion, conditioning, and injury prevention. This study compared the neuromechanics (ground reaction and joint kinetics, kinematics and muscle activity) of middle-distance athletes running on an instrumented treadmill at six wide-ranging speeds (2.78-8.33 m·s-1). Ground reaction forces and kinematics were analyzed using inverse dynamics to calculate flexor and extensor joint torques, and positive and negative work done by these torques. Contributions of each functional muscle group to the total positive and negative work done by the limb during stance, swing, and the whole stride were quantified. During stance, the ankle plantar flexors were the major energy generator and absorber (>60%) at all speeds, but their contribution to whole stride energy generation and absorption declined with speed. Positive work by the hip extensors rose superlinearly with speed during stance (3-fold) and especially during swing (12-fold), becoming the biggest energy generator across the whole stride at >5 m·s-1. Knee flexor and extensor negative work also rose superlinearly with speed during swing, with the knee flexors becoming the greatest energy absorber over the whole stride at >7.22 m·s-1. Across speeds, plantar flexor peak moment and positive work accounted for 97% and 96% of the variance in step length, and swing hip extension peak moment and positive work accounted for 98% and 99% of the variance in step frequency. There were pronounced speed, phase (stance/swing), and work (positive/negative) dependent contributions of the different functional muscle groups during running, with extensive implications for conditioning and injury prevention.

Bone injury imaging in knee and ankle joints using fast-field-echo resembling a CT using restricted echo-spacing MRI: a feasibility study.

Purpose: To explore the consistency of FRACTURE (Fast-field-echo Resembling A CT Using Restricted Echo-spacing) MRI and X-Ray/computerized tomography (CT) in the evaluation of bone injuries in knee and ankle joints. Methods: From Nov. 2020 to Jul. 2023, 42 patients with knee joint or ankle joint injuries who underwent FRACTURE MRI examinations were retrospectively collected. 11 patients were examined by both X-Ray and FRACTURE examinations. 31 patients were examined by both CT and FRACTURE examinations. The fracture, osteophyte, and bone destruction of the joints were evaluated by two radiologists using X-Ray/CT and FRACTURE images, respectively. Kappa test was used for consistency analysis. Results: The evaluation consistency of fracture, osteophyte and bone destruction via X-Ray and FRACTURE images by radiologist 1 were 0.879, 0.867 and 0.847 respectively, and for radiologist 2 were 0.899, 0.930, and 0.879, respectively. The evaluation consistency of fracture, osteophyte and bone destruction via CT and FRACTURE images by radiologist 1 were 0.938, 0.937 and 0.868 respectively, and for radiologist 2 were 0.961, 0.930, and 0.818, respectively. Conclusion: For fracture, osteophyte, and bone destruction of knee and ankle joints. FRACTURE MRI showed a high consistency with X-Ray/CT examinations.

The Pediatric Ankle: Normal Variations and Maturation-Dependent Pathology.

The pediatric ankle can present a broad range of normal variation and pathology unique to certain stages of development. Understanding the expected age ranges of ossification and fusion about the ankle is essential to provide accurate diagnoses regarding skeletal integrity. This conclusion has been well characterized radiographically and is supported by cadaveric research.The range of appearances on magnetic resonance imaging has also been well described. Knowledge about the structure of the periosteum and perichondrium aids in image interpretation as well as explaining typical injury patterns. The expected appearance of the physis and regional bone marrow signal is also of utmost importance.Ultrasonography is a valuable tool in pediatric musculoskeletal imaging but is limited when there is concern for intra-articular pathology. Computed tomography tends to be reserved for preoperative evaluation. We describe normal variation and maturation-dependent pathology of the pediatric ankle with an emphasis on imaging considerations.

[Synchronous analysis of ankle coronal plane tilt angle and peripheral associated muscle load in semi-squat landing of paratroopers].

Objective: To investigate the relationship between ankle stability and associated muscle load around the ankle and the effect of a parachute ankle brace (PAB) on ankle inversion and associated muscle load around the ankle during landing through the simulated paratrooper semi-squat landing field experiment. Methods: In August 2021, 37 male paratroopers were randomly selected as the study objects to perform parachute landing training in the semi-squat posture on the 1.5 m and 2.0 m jump platforms with or without PAB, respectively. The coronal plane tilt angle of ankle joint and the percentage of maximum voluntary contraction (MVC%) of associated muscles around ankle joint during the process were measured and correlation analysis was conducted. And the effect of wearing PAB on the coronal plane tilt angle of ankle joint and the associated muscles around the ankle joint was analyzed. Results: During the semi-squat landing, the MVC% of the tibialis anterior muscle, lateral gastrocnemius muscle and peroneus longus muscle were positively correlated with the ankle coronal plane tilt angle in paratroopers wearing and without wearing PAB, and the correlations were statistically significant (P<0.05). At the same height, compared with those without PAB, the coronal plane tilt angle of the ankle joint decreased during semi-squat landing in paratroopers PAB, and the differences were statistically significant (P<0.05). At the landing moment of the same height, compared with those without PAB, the MVC% of lateral gastrocnemius muscle decreased and the MVC% of peroneus longus muscle increased in paratroopers wearing PAB, and the differences were statistically significant (P<0.05). After the landing moment until the standing stage (100-200 ms) at 1.5 m height, the MVC% of the tibialis anterior muscle decreased in paratroopers wearing PAB compared with those without PAB, and the differences were statistically significant (P<0.05). In the post-standing stage (200 ms) at 2.0 m height, the MVC% of the tibialis anterior muscle decreased in paratroopers wearing PAB compared with those without PAB, and the difference was statistically significant (P<0.05) . Conclusion: Wearing PAB can reduce the ankle coronal plane tilt angle, improve ankle stability, reduce the muscle load of the lateral gastrocnemius muscle at the moment of landing, and reduce the load of the tibialis anterior muscle after landing, but increase the peroneus longus muscle load at the moment of landing.