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1.
Biomolecules ; 14(6)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38927101

RESUMEN

In recent years, there has been growing interest in the development of metal-free, environmentally friendly, and cost-effective biopolymer-based piezoelectric strain sensors (bio-PSSs) for flexible applications. In this study, we have developed a bio-PSS based on pure deoxyribonucleic acid (DNA) and curcumin materials in a thin-film form and studied its strain-induced current-voltage characteristics based on piezoelectric phenomena. The bio-PSS exhibited flexibility under varying compressive and tensile loads. Notably, the sensor achieved a strain gauge factor of 407 at an applied compressive strain of -0.027%, which is 8.67 times greater than that of traditional metal strain gauges. Furthermore, the flexible bio-PSS demonstrated a rapid response under a compressive strain of -0.08%. Our findings suggest that the proposed flexible bio-PSS holds significant promise as a motion sensor, addressing the demand for environmentally safe, wearable, and flexible strain sensor applications.


Asunto(s)
Técnicas Biosensibles , Curcumina , ADN , Grafito , Curcumina/química , ADN/química , Grafito/química , Biopolímeros/química , Técnicas Biosensibles/métodos
2.
Clin Orthop Surg ; 16(3): 455-460, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38827760

RESUMEN

Background: Total ankle arthroplasty (TAA) enhances patients' subjective outcomes with respect to pain and function. The aim of this study was to analyze the biomechanical changes of the affected limb following TAA using gait analysis with a 3-dimensional multi-segment foot model (3D MFM). Methods: We reviewed medical records, simple radiographs, and gait analyses using a 3D MFM of patients who underwent TAA for severe varus ankle arthritis. Preoperative and postoperative gait data of 24 patients were compared. Postoperative gait analyses were done at least 1 year after surgery. Results: TAA significantly increased stride length (p = 0.024). The total range of motion of all planes in the hindfoot and forefoot showed no significant changes between preoperative and postoperative states. Hindfoot was significantly plantarflexed and pronated after TAA, while forefoot was significantly supinated in all phases. After appropriate calculations, the genuine coronal motion of the hindfoot showed no changes after TAA in all phases. Conclusions: TAA did not result in biomechanical improvements of segmental motions in the forefoot and hindfoot, except for changes to the bony structures. Therefore, it is important to point out to patients that TAA will not result in significant improvement of ankle function and range of motion. Clinicians can consider this information during preoperative counseling.


Asunto(s)
Artroplastia de Reemplazo de Tobillo , Rango del Movimiento Articular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Articulación del Tobillo/cirugía , Articulación del Tobillo/fisiopatología , Articulación del Tobillo/diagnóstico por imagen , Fenómenos Biomecánicos , Análisis de la Marcha , Imagenología Tridimensional , Estudios Retrospectivos , Marcha/fisiología , Anciano de 80 o más Años
3.
J Clin Med ; 13(9)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38731253

RESUMEN

Background/Objectives: This study aimed to evaluate the efficacy of application-linked stretching ball instruments that record the rolling time and force of patients compared with a traditional simple stretching ball. Methods: Fourteen participants with plantar fasciitis were divided into a simple massage ball group (group A, n = 8) and an application-linked massage ball group (group B, n = 6). The application-linked massage ball sends information regarding the massages, such as the frequency and force of the massage on the foot, to the application on the patient's smartphone. All clinical outcomes were evaluated at the beginning of the study and 1-, 2-, and 3-month follow-up. The primary outcome measure was the Manchester-Oxford Foot Questionnaire (MOXFQ) score. Results: At the beginning of the study, the initial MOXFQ score was not significantly different between the two groups (p = 0.948). At each time point, the MOXFQ score of the whole population did not improve significantly compared to that of the initial state (p = 0.131). Generalized estimating equation modeling demonstrated that there was no significant difference in the improvement of the MOXFQ score between groups A and B during follow-up (p = 0.826). In addition, no group-by-time interactions were observed (p = 0.457). Conclusions: The efficacy of an application-linked massage ball for the treatment of plantar fasciitis was not as definite as that of a traditional simple stretching ball in patients whose symptoms persisted for at least six months. Future studies that include patients with acute plantar fasciitis are required.

4.
J Orthop Surg (Hong Kong) ; 32(2): 10225536241258331, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38814119

RESUMEN

PURPOSE: A fundamental understanding of plantar pressure distribution is important for prescribing an appropriate orthosis and applying nonoperative methods, such as stretching exercises, for the treatment of plantar fasciitis. Despite existing research on plantar pressure distribution, discrepancies between affected and unaffected sides in unilateral plantar fasciitis patients warrant further investigation. This study aimed to evaluate the plantar pressure distribution in patients with unilateral plantar fasciitis by comparing it with that on the contralateral unaffected side. METHODS: We retrospectively reviewed records from 20 consecutive patients diagnosed with unilateral plantar fasciitis, using the unaffected side as the control. The emed® pedobarographic system was used to measure the plantar pressure distribution during gait. The analysis was performed using a 4-mask configuration (toes, forefoot, midfoot, and hindfoot). RESULTS: Both sides showed no significant differences in radiographic parameters. The affected side showed a significantly higher contact area, maximum force, and force-time integrals in the midfoot. However, the unaffected side demonstrated significantly higher maximum force and force-time integrals in the hindfoot. There was no difference in the distribution of the peak pressure and pressure-time integrals between the two sides in all mask regions. The increased contact area and maximum force in the midfoot on the side with plantar fasciitis may result from heel pain-induced weight transfer from the hindfoot. CONCLUSION: The findings of this study provide a basic understanding of plantar pressure distribution in the treatment of plantar fasciitis and highlight the importance of considering inter-side differences when designing treatment interventions or orthotic devices.


Asunto(s)
Fascitis Plantar , Pie , Presión , Humanos , Fascitis Plantar/fisiopatología , Fascitis Plantar/terapia , Estudios Retrospectivos , Femenino , Masculino , Persona de Mediana Edad , Adulto , Pie/fisiopatología , Anciano , Marcha/fisiología
5.
Clin Orthop Surg ; 16(2): 322-325, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38562628

RESUMEN

Background: Toe symphalangism is characterized by a fusion of the interphalangeal joint between the middle and distal phalanges. While typical lesser toe fractures heal well with conservative treatment, in our clinical experience, we encountered patients with symphalangeal toe fractures who experienced long-lasting pain and delayed radiographic union. Therefore, this study aimed to report radiographic outcomes following conservative treatment of symphalangeal fractures of the lesser toes. Methods: We retrospectively reviewed 14 patients with symphalangeal lesser toe fractures who were treated conservatively. We investigated the mechanism of injury and measured the time from the initial injury date to the complete radiographic union. The fracture gap distance was measured on an initial lateral radiograph. Results: Symphalangeal fractures involved the fourth toe in 4 patients (28.5%) and the fifth toe in 10 patients (71.4%). Regarding the mechanism of injury, 6 patients (42.9%) were injured by stubbing or bumping into the door, 5 patients (35.7%) were injured by tripping, 2 patients (14.3%) were injured by heavy objects falling directly on their toes, and 1 patient (2.3%) complained of pain after wearing pointed shoes for half a day. The mean time to complete union was 9.1 months, and the median period was 5.5 months (range, 0.8-29 months). The initial gap of the fracture was 0.60 mm (range, 0.30-1.04 mm). Conclusions: The results of our case series may help counsel patients in the outpatient clinic that prolonged healing time may be required for the union of symphalangeal toe fractures.


Asunto(s)
Traumatismos del Tobillo , Fracturas Óseas , Traumatismos de la Rodilla , Humanos , Tratamiento Conservador , Estudios Retrospectivos , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/terapia , Dedos del Pie/lesiones , Dolor , Resultado del Tratamiento
6.
Foot Ankle Orthop ; 9(2): 24730114241242782, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38601322
7.
J Orthop Surg Res ; 19(1): 202, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532518

RESUMEN

BACKGROUND: The biomechanics of the hindfoot in ankle osteoarthritis (OA) are not yet fully understood. Here, we aimed to identify hindfoot motion in a gait analysis using a multi-segment foot model (MFM) according to ankle OA stage and the presence of subtalar compensation defined by hindfoot alignment. METHODS: We retrospectively reviewed the medical records, plain radiographs, and gait MFM data of 54 ankles admitted to our hospital for the treatment of advanced ankle OA. Spatiotemporal gait parameters and three-dimensional motions of the hindfoot segment were analyzed according to sex, age, body mass index, Takakura classification, and the presence of subtalar compensation. Twenty ankles were categorized as compensated group, and 34 ankles as decompensated group. RESULTS: No spatiotemporal gait parameters differed significantly according to the presence of subtalar compensation or ankle OA stage. Only normalized step width differed significantly (P = 0.028). Average hindfoot motion (decompensation vs. compensation) did not differ significantly between the sagittal and transverse planes. Graphing of the coronal movement of the hindfoot revealed collapsed curves in both groups that differed significantly. Compared with Takakura stages 3a, 3b, and 4, cases of more advanced stage 3b had a smaller sagittal range of motion than those of stage 3a (P = 0.028). Coronal movement of the hindfoot in cases of Takakura stage 3a/3b/4 showed a relatively flat pattern. CONCLUSIONS: The spatiotemporal parameters were not affected by the hindfoot alignment resulting from subtalar compensation. The sagittal range of hindfoot motion decreased in patients with advanced ankle OA. Once disrupted, the coronal movement of the subtalar joint in ankle OA did not change regardless of ankle OA stage or hindfoot compensation state.


Asunto(s)
Tobillo , Osteoartritis , Humanos , Estudios Retrospectivos , Articulación del Tobillo , Pie
8.
J Bone Joint Surg Am ; 106(9): 801-808, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38346100

RESUMEN

BACKGROUND: Physical skeletal loading can affect the bone mineral density (BMD). This study investigated the association between BMD and dynamic foot pressure during gait. METHODS: A total of 104 patients (mean age, 62.6 ± 12.4 years; 23 male and 81 female) who underwent dual x-ray absorptiometry and pedobarography were included. BMD values of the lumbar spine, femoral neck, and total femur were assessed. The mean and maximum pressures were measured at the hallux, lesser toes, 1st metatarsal head, 2nd and 3rd metatarsal heads, 4th and 5th metatarsal heads, midfoot, medial heel, and lateral heel. Multivariable regression analysis was performed to identify factors significantly associated with BMD. RESULTS: The lumbar spine BMD was significantly associated with the mean pressure at the 4th and 5th metatarsal heads (p = 0.041, adjusted R 2 of model = 0.081). The femoral neck BMD was significantly associated with the maximum pressure at the 2nd and 3rd metatarsal heads (p = 0.002, adjusted R 2 = 0.213). The total femoral BMD also showed a significant association with the maximum pressure at the 2nd and 3rd metatarsal heads (p = 0.003, adjusted R 2 = 0.360). CONCLUSIONS: Foot plantar pressure during gait was significantly associated with BMD, and could potentially be used to predict the presence of osteoporosis. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.


Asunto(s)
Absorciometría de Fotón , Densidad Ósea , Pie , Presión , Caminata , Humanos , Femenino , Masculino , Persona de Mediana Edad , Densidad Ósea/fisiología , Anciano , Pie/fisiología , Caminata/fisiología , Osteoporosis/fisiopatología , Cuello Femoral/diagnóstico por imagen , Cuello Femoral/fisiología , Vértebras Lumbares , Marcha/fisiología
9.
Clin Orthop Surg ; 16(1): 125-133, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38304216

RESUMEN

Background: Foot deformities can cause abnormal biomechanics of the ankle joint and the development of osteoarthritis. It was hypothesized that foot deformities would be related to medial ankle osteoarthritis, and this study investigated this relationship using radiographic measurements. Methods: Seventy-six ankles of 76 patients (32 men and 44 women; mean age, 69.0 years) with medial ankle osteoarthritis were included. Eleven radiographic measurements evaluated ankle joint orientation (tibial plafond inclination [TPI], medial distal tibial angle [MDTA], and anterior distal tibial angle [ADTA]), ankle joint incongruency (tibiotalar tilt [TT]), foot deformities (lateral talo-first metatarsal angle [Lat talo-1MT], anteroposterior talo-first metatarsal angle [AP talo-1MT], and talonavicular coverage), talar body migration (medial talar center migration [MTCM] and anterior talar center migration [ATCM]), internal rotation (IR) of the talus, and mechanical tibiofemoral angle. All were statistically analyzed using Pearson's correlation coefficients and regression analyses. Results: Ankle joint orientation to the ground (TPI, p = 0.002), increased foot arch (Lat talo-1MT, p < 0.001), and IR of the talus (p = 0.001) were significantly associated with ankle joint incongruency (TT) in linear regression analysis. Ankle joint incongruency (TT, p = 0.003), medial talar body migration (MTCM, p = 0.042), and increased foot arch (Lat talo-1MT, p = 0.022) were significantly associated with IR of the talus in the binary logistic regression analysis. MTCM was significantly correlated with TPI (r = 0.251, p = 0.029), TT (r = 0.269, p = 0.019), MDTA (r = 0.359, p = 0.001), ATCM (r = -0.522, p < 0.001), and AP talo-1MT (r = 0.296, p = 0.015). ATCM was significantly correlated with TPI (r = -0.253, p = 0.027), ADTA (r = 0.349, p = 0.002), and Lat talo-1MT (r = -0.344, p = 0.002). Conclusions: Ankle joint orientation, foot deformities, and talar rotation were associated with ankle joint incongruency in medial ankle osteoarthritis when evaluated radiographically. These findings need to be considered during surgical treatment for medial ankle osteoarthritis. However, the biomechanical significance of these radiographic measurements requires further investigation.


Asunto(s)
Diterpenos , Deformidades del Pie , Osteoartritis de la Rodilla , Masculino , Humanos , Femenino , Anciano , Tobillo , Estudios Retrospectivos , Articulación del Tobillo/diagnóstico por imagen , Articulación del Tobillo/cirugía
10.
Clin Orthop Surg ; 16(1): 1-6, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38304213

RESUMEN

Checkrein deformity is characterized by the dynamic status of the hallux, in which flexion deformity is aggravated by ankle dorsiflexion and relieved by ankle plantarflexion. In most cases, a checkrein deformity occurs secondary to trauma or following surgery. It has been suggested that the flexor hallucis longus tendon tethers or entraps scar tissue or fracture sites. Improvement with conservative treatment is difficult once the deformity has already become entrenched, and surgical management is usually required in severe cases. Various surgical options are available for the correction of checkrein deformities. It includes a simple release of adhesion at the fracture site; lengthening of the flexor hallucis longus by Z-plasty at the fracture site combined with the release of adhesion; lengthening of the flexor hallucis longus by Z-plasty at the midfoot, retromalleolar, or tarsal tunnel area; and flexor hallucis longus tenotomy with interphalangeal arthrodesis for recurrent cases. This review aimed to summarize the overall etiology, relevant anatomy, diagnosis, and treatment of checkrein deformities described in the literature.


Asunto(s)
Traumatismos del Tobillo , Deformidades Adquiridas del Pie , Traumatismos de los Tendones , Humanos , Deformidades Adquiridas del Pie/complicaciones , Deformidades Adquiridas del Pie/cirugía , Tendones/cirugía , Tenotomía , Traumatismos de los Tendones/cirugía , Traumatismos del Tobillo/cirugía
11.
BMC Musculoskelet Disord ; 25(1): 85, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38254084

RESUMEN

BACKGROUND: This retrospective cohort study aimed to investigate the natural history of talar avascular necrosis (AVN) during short-term outpatient follow-up and to identify the risk factors for progression to collapse and arthritic changes. METHODS: Thirty-four cases of talar AVN from 34 patients (15 males, 19 females) were included. The mean age of the patients was 48.9 years (SD 16.0 years) and the mean follow-up period was 39.5 months (SD 42.0 months). The patients were divided into two groups i.e., progression and non-progression groups. The progression group consisted of those who showed aggravation of the Ficat stage during the follow-up period or advanced arthritis of the ankle joint (Ficat stage 4) at presentation. Demographic data and information regarding BMI, medical comorbidities, trauma history, bilaterality, and location of the lesion (shoulder vs. non-shoulder lesions) were collected. Following the univariate analysis, a binary logistic regression analysis was performed. RESULTS: The location of the talar AVN was the only significant factor (p = 0.047) associated with disease progression. A total of 14.3% (2 of 14) of the central (non-shoulder) talar AVN lesions showed progression, while 50% (10 of 20) of shoulder lesions aggravated during follow-up. Age, sex, bilaterality, medical comorbidities, and trauma history were not associated with progressive talar collapse or subsequent arthritic changes in talar AVN. CONCLUSIONS: Conservative treatment should be considered for a central lesion of the talar AVN because it tends to remain stable without progression. A more comprehensive study with a larger study population is required to establish the surgical indications for talar AVN. LEVEL OF EVIDENCE: Prognostic level III.


Asunto(s)
Osteonecrosis , Femenino , Masculino , Humanos , Persona de Mediana Edad , Estudios de Seguimiento , Estudios Retrospectivos , Osteonecrosis/epidemiología , Osteonecrosis/etiología , Articulación del Tobillo , Progresión de la Enfermedad
12.
Arch Orthop Trauma Surg ; 144(2): 567-574, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37880455

RESUMEN

INTRODUCTION: Although intramedullary nailing is a popular method for tibiotalocalcaneal arthrodesis, nonunion is one of the most commonly reported complications. This study aimed to evaluate the fusion rate, improvement in functional outcomes, and occurrence of complications in tibiotalocalcaneal arthrodesis using retrograde intramedullary nailing with partial fibulectomy and onlay bone graft technique. MATERIALS AND METHODS: Twenty-six consecutive patients using the proposed technique were retrospectively reviewed. For radiographic outcomes, the union rate, alignment, and any related complications were assessed. Functional outcomes were evaluated using the American Orthopedic Foot and Ankle Society hindfoot scale, Foot and Ankle Outcome Score, and visual analog scale, preoperatively and at the final follow-up. RESULTS: The mean follow-up period was 38.2 months. The tibiotalar joint achieved complete union in 80.8% at six months postoperatively, while all the cases achieved complete union at 12 months postoperatively. However, the subtalar joint achieved complete union in 26.9% at six months postoperatively, which gradually increased to 73.1% at 12 months postoperatively, and 80.8% at the final follow-up without revision surgery. A subgroup analysis showed there was a trend of higher subtalar fusion rate when an additional screw for the subtalar joint fixation was placed (86.7% vs. 54.5%). The functional outcomes significantly improved at the final follow-up. A few minor complications occurred, including surgical site infection, irritational symptoms, and metal failure; however, they eventually resolved. CONCLUSIONS: Our technique of tibiotalocalcaneal arthrodesis with partial fibulectomy and onlay bone grafting could be a good option where both the tibiotalar and subtalar joints need to be fused.


Asunto(s)
Fijación Intramedular de Fracturas , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Fijación Intramedular de Fracturas/métodos , Trasplante Óseo/métodos , Artrodesis/métodos , Articulación del Tobillo/cirugía , Clavos Ortopédicos
13.
Nanomaterials (Basel) ; 13(24)2023 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-38133056

RESUMEN

It is essential to understand the barrier height, ideality factor, and role of inhomogeneities at the metal/semiconductor interfaces in nanowires for the development of next generation nanoscale devices. Here, we investigate the drain current (Ids)-gate voltage (Vgs) characteristics of GaN nanowire wrap-gate transistors (WGTs) for various gate potentials in the wide temperature range of 130-310 K. An anomalous reduction in the experimental barrier height and rise in the ideality factor with reducing the temperature have been perceived. It is noteworthy that the variations in barrier height and ideality factor are attributed to the spatial barrier inhomogeneities at the AlGaN/GaN interface in the GaN nanowire WGTs by assuming a double Gaussian distribution of barrier heights at 310-190 K (distribution 1) and 190-130 K (distribution 2). The standard deviation for distribution 2 is lower than that of distribution 1, which suggests that distribution 2 reflects more homogeneity at the AlGaN/GaN interface in the transistor's source/drain regions than distribution 1.

14.
J Clin Med ; 12(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37959367

RESUMEN

Various modifications of distal chevron metatarsal osteotomy (DCMO) have been introduced for correcting moderate hallux valgus deformity; however, the amount of correction may be limited, and complications, such as the recurrence of the deformity and avascular necrosis of the metatarsal head, have been a problem. This study aimed to present a modified 90-degree DCMO technique that overcomes the previously reported shortcomings and to report a successful short-term radiographic outcome. Sixty-eight consecutive patients who underwent the operation with our modified DCMO technique and twenty-two consecutive patients with the conventional DCMO technique (control group) were retrospectively analyzed. The radiographic measurements were evaluated preoperatively, at two months post operation, and at the final follow-up. Both groups showed a significant correction of the hallux valgus angle, first-second intermetatarsal angle, distal metatarsal articular angle, and sesamoid position at the final follow-up, while the amount of correction was significantly greater in the modified DCMO group. In both groups, there were no cases of complications such as avascular necrosis of the metatarsal head, nonunion, and surgical site infection appearing throughout the follow-up period. Therefore, the modified 90-degree DCMO technique is effective and safe, which could serve as a favorable option to treat moderate hallux valgus deformity.

15.
PLoS One ; 18(11): e0286013, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37917738

RESUMEN

OBJECTIVES: The effects of foot deformities and corrections on the ankle joint without osteoarthritis has received little attention. This study aimed to investigate the effect of flatfoot correction on the ankle joint of patients without osteoarthritis. METHODS: Thirty-five patients (24 men and 11 women; mean age 17.5 years) who underwent lateral column lengthening for flatfoot deformities were included. The mean postoperative follow-up period was 20.5 months (standard deviation [SD]: 15.7 months). Radiographic indices were measured pre- and postoperatively, including anteroposterior (AP) and lateral talo-first metatarsal angles, naviculocuboid overlap, position of the articulating talar surface, and lateral talar center migration. Postoperative changes in the radiographic indices were statistically analyzed. RESULTS: There was significant postoperative improvement in flatfoot deformity in terms of AP and lateral talo-first metatarsal angles (p<0.001 and p<0.001, respectively) and naviculocuboid overlap (p<0.001). On lateral radiographs, the talar articulating surface dorsiflexed by 7.3% (p<0.001), and the center of the talar body shifted anteriorly by 0.85 mm (p<0.001) postoperatively. CONCLUSIONS: Flatfoot correction using lateral column and Achilles tendon lengthening caused dorsiflexion and an anterior shift of the articular talar body in patients without osteoarthritis. Correction of flatfoot deformity might affect the articular contact area at the ankle joint. The biomechanical effects of this change need to be investigated further.


Asunto(s)
Pie Plano , Osteoartritis , Masculino , Humanos , Femenino , Adolescente , Pie Plano/diagnóstico por imagen , Pie Plano/cirugía , Articulación del Tobillo/diagnóstico por imagen , Articulación del Tobillo/cirugía , Estudios Retrospectivos , Transferencia Tendinosa/efectos adversos , Osteoartritis/complicaciones
16.
J Neuroeng Rehabil ; 20(1): 140, 2023 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-37864265

RESUMEN

BACKGROUND: Foot drop is a neuromuscular disorder that causes abnormal gait patterns. This study developed a pneumatically powered ankle-foot orthosis (AFO) to improve the gait patterns of patients with foot drop. We hypothesized that providing unilateral ankle dorsiflexion assistance during the swing phase would improve the kinematics and spatiotemporal gait parameters of such patients. Accordingly, this study aims to examine the efficacy of the proposed assistance system using a strategy for joint kinematics and spatiotemporal gait parameters (stride length, swing velocity, and stance phase ratio). The analysis results are expected to provide knowledge for better design and control of AFOs in patients with foot drop. METHOD: Ten foot drop patients with hemiparesis (54.8 y ± 14.1 y) were fitted with a custom AFO with an adjustable calf brace and portable air compressor for ankle dorsiflexion assistance in the gait cycle during the swing phase. All subjects walked under two different conditions without extensive practice: (1) barefoot and (2) wearing a powered AFO. Under each condition, the patients walked back and forth on a 9-m track with ten laps of level ground under the supervision of licensed physical therapists. The lower-limb joint and trunk kinematics were acquired using 12 motion-capture cameras. RESULTS: We found that kinematic asymmetry decreased in the three lower-limb joints after ankle dorsiflexion assistance during the swing phase. The average ankle-joint angle increased after using the AFO during the entire gait cycle. Similarly, the knee-joint angle showed a slight increase while using the AFO, leading to a significantly decreased standard deviation within patients. Conversely, the hip-joint angle showed no significant improvements with assistance. While several patients exhibited noticeably lower levels of asymmetry, no significant changes were observed in the average asymmetry of the swing velocity difference between the affected and unaffected sides while using the AFO. CONCLUSION: We experimentally validated that ankle dorsiflexion assistance during the swing phase temporarily improves gait asymmetry in foot-drop patients. The experimental results also prove the efficacy of the developed AFO for gait assistance in foot-drop patients.


Asunto(s)
Ortesis del Pié , Trastornos Neurológicos de la Marcha , Neuropatías Peroneas , Humanos , Tobillo , Ortesis del Pié/efectos adversos , Neuropatías Peroneas/complicaciones , Marcha , Articulación del Tobillo , Debilidad Muscular , Paresia , Fenómenos Biomecánicos , Trastornos Neurológicos de la Marcha/etiología
17.
Nanomaterials (Basel) ; 13(14)2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37513143

RESUMEN

We used capacitance-voltage (C-V), conductance-voltage (G-V), and noise measurements to examine the carrier trap mechanisms at the surface/core of an AlGaN/GaN nanowire wrap-gate transistor (WGT). When the frequency is increased, the predicted surface trap density promptly drops, with values ranging from 9.1 × 1013 eV-1∙cm-2 at 1 kHz to 1.2 × 1011 eV-1∙cm-2 at 1 MHz. The power spectral density exhibits 1/f-noise behavior in the barrier accumulation area and rises with gate bias, according to the 1/f-noise features. At lower frequencies, the device exhibits 1/f-noise behavior, while beyond 1 kHz, it exhibits 1/f2-noise behavior. Additionally, when the fabricated device governs in the deep-subthreshold regime, the cutoff frequency for the 1/f2-noise features moves to the subordinated frequency (~102 Hz) side.

18.
J Child Orthop ; 17(3): 224-231, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37288045

RESUMEN

Background: Osteochondral lesions of the talus are uncommon in children and adolescents. Surgical procedures differ from those used for adults to avoid iatrogenic physeal injuries. This study aimed to evaluate the clinical and radiological outcomes of surgical treatment in pediatric patients with osteochondral lesions, specifically investigating the patient age and the status of distal tibial physis as factors associated with surgical success. Methods: We retrospectively reviewed 28 patients who had symptomatic osteochondral lesions of the talus that were treated surgically between 2003 and 2016. If the lesion was stable and articular cartilage was intact, retrograde drilling was performed under fluoroscopic guidance. Lesions with detached overlying cartilages were treated by debridement of the cartilage combined with microfracture and drilling. Radiographic outcomes, American Orthopaedic Foot & Ankle Society ankle-hindfoot score, and skeletal maturity were evaluated. Results: Radiological improvement was observed in 24 (24/28, 86%) patients and complete and incomplete healing in 8 and 16 patients, respectively. Changes in pain grades, American Orthopaedic Foot & Ankle Society scores, and radiological healing after surgery were significant (pain grade, p < 0.001; American Orthopaedic Foot & Ankle Society, p = 0.018; radiological healing, p < 0.001). In addition, patients in the younger age group (≤13 years) showed greater improvements in pain grades than older patients (p = 0.02). Improvement in pain grade after surgery was better in the skeletally immature group than in the skeletally mature group (p = 0.048). Conclusion: Clinical and radiological improvements were observed after surgical treatment. The younger age group and open physis group showed more pain improvement. Level of evidence: Therapeutic level IV.

19.
Foot Ankle Surg ; 29(5): 436-440, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37301676

RESUMEN

BACKGROUND: This study aimed to determine the clinical effect of incongruent subtalar joint space on total ankle arthroplasty (TAA). METHODS: Thirty-four consecutive patients who underwent TAA were grouped according to the status of subtalar joint incongruency. A comparison of clinical and radiographic parameters between groups as well as multiple regression analysis was performed to identify contributing factors to the final functional outcome. RESULTS: The final American Orthopaedic Foot and Ankle Society (AOFAS) score was significantly higher in the congruent group compared to that of the incongruent group (p = 0.007). There were no significant differences between the two groups in measured radiographic angles. In multiple regression analysis, the female sex (p = 0.006) and incongruency of the subtalar joint (p = 0.013) were found to be significant contributing factors to the final AOFAS score. CONCLUSIONS: A thorough preoperative investigation should be taken into the state of the subtalar joint for TAA.


Asunto(s)
Artroplastia de Reemplazo de Tobillo , Articulación Talocalcánea , Humanos , Femenino , Articulación Talocalcánea/diagnóstico por imagen , Articulación Talocalcánea/cirugía , Tobillo/cirugía , Resultado del Tratamiento , Artrodesis , Articulación del Tobillo/diagnóstico por imagen , Articulación del Tobillo/cirugía , Estudios Retrospectivos
20.
Foot Ankle Int ; 44(7): 656-664, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37102369

RESUMEN

BACKGROUND: It is unknown whether perioperative bisphosphonate (BP) use reduces revision rates in total ankle replacement arthroplasty (TAR) although its effect has been demonstrated to be effective in reducing revision rates in total knee or hip replacement arthroplasty. METHODS: We reviewed National Health Insurance Service data based on national health insurance service claims data and health care utilization, health screening, sociodemographic variables, medication history, operation codes, and mortality data for 50 million Koreans. From 2002 to 2014, 6391 of 7300 patients who underwent TAR were BP nonusers, whereas 909 patients were BP users. The revision rate according to BP medication and comorbidities was investigated. The Kaplan-Meier estimate and extended Cox proportional hazard model were also used. RESULTS: The revision rate of TAR was 7.9% for BP users and 9.5% for BP nonusers, which showed no significant difference (P = .251). Implant survival over time decreased constantly. Adjusted hazard ratio for hypertension was 1.242 (P = .017), whereas other comorbidities such as diabetes had no effect on the revision rate of TAR. CONCLUSION: We found that the perioperative BP use did not reduce the revision rate of TAR. Comorbidities (except hypertension) did not affect the revision rate of TAR. More research regarding various factors affecting the revision of TAR could be warranted. LEVEL OF EVIDENCE: Level III, retrospective cohort study.


Asunto(s)
Artroplastia de Reemplazo de Tobillo , Artroplastia de Reemplazo de Cadera , Humanos , Tobillo , Difosfonatos/uso terapéutico , Falla de Prótesis , Sistema de Registros , Reoperación , Estudios Retrospectivos , Resultado del Tratamiento
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