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Journal of Orthopaedic Research :... Nov 2021Persons with ankle osteoarthritis (AOA) often seek surgical intervention to alleviate pain and restore function; however, recent research has yielded no superior choice...
Persons with ankle osteoarthritis (AOA) often seek surgical intervention to alleviate pain and restore function; however, recent research has yielded no superior choice between the two primary options: fusion and replacement. One factor yet to be considered is the effect of footwear on biomechanical outcomes. Comparisons of AOA biomechanics to a normative population are also sparse. The objectives of this study were to (1) determine how footwear uniquely affected gait in persons with ankle fusion and replacement and (2) provide context for AOA biomechanics via comparisons to a healthy adult sample. Thirty-four persons with AOA performed overground walking trials barefoot and shod before surgical intervention and then received either an ankle fusion (n = 14) or replacement (n = 20). Two and/or three years post-surgery, patients returned for gait analysis. Nineteen controls performed the same gait procedures during a single study visit. Spatiotemporal variables and peak angles, internal moments, powers, and forces were calculated to quantify gait behavior. Overall, the two surgical groups performed similarly to each other but demonstrated marked differences from controls both pre- and post-surgery. No significant differences were detected when examining the effect of footwear. The motion of the midfoot with respect to the hindfoot and forefoot may be instrumental in gait biomechanics following an ankle fusion or replacement and should be considered in future investigations.
Topics: Adult; Ankle; Ankle Joint; Biomechanical Phenomena; Gait; Humans; Osteoarthritis; Shoes; Walking
PubMed: 33458862
DOI: 10.1002/jor.24988 -
Journal of Neuroengineering and... Jun 2023Balance control is important for mobility, yet exoskeleton research has mainly focused on improving metabolic energy efficiency. Here we present a biomimetic exoskeleton...
BACKGROUND
Balance control is important for mobility, yet exoskeleton research has mainly focused on improving metabolic energy efficiency. Here we present a biomimetic exoskeleton controller that supports walking balance and reduces muscle activity.
METHODS
Humans restore balance after a perturbation by adjusting activity of the muscles actuating the ankle in proportion to deviations from steady-state center of mass kinematics. We designed a controller that mimics the neural control of steady-state walking and the balance recovery responses to perturbations. This controller uses both feedback from ankle kinematics in accordance with an existing model and feedback from the center of mass velocity. Control parameters were estimated by fitting the experimental relation between kinematics and ankle moments observed in humans that were walking while being perturbed by push and pull perturbations. This identified model was implemented on a bilateral ankle exoskeleton.
RESULTS
Across twelve subjects, exoskeleton support reduced calf muscle activity in steady-state walking by 19% with respect to a minimal impedance controller (p < 0.001). Proportional feedback of the center of mass velocity improved balance support after perturbation. Muscle activity is reduced in response to push and pull perturbations by 10% (p = 0.006) and 16% (p < 0.001) and center of mass deviations by 9% (p = 0.026) and 18% (p = 0.002) with respect to the same controller without center of mass feedback.
CONCLUSION
Our control approach implemented on bilateral ankle exoskeletons can thus effectively support steady-state walking and balance control and therefore has the potential to improve mobility in balance-impaired individuals.
Topics: Humans; Exoskeleton Device; Electromyography; Ankle; Ankle Joint; Walking; Biomechanical Phenomena; Gait
PubMed: 37370175
DOI: 10.1186/s12984-023-01205-9 -
Scientific Reports Dec 2022Postural control research has focused on standing balance experiments on platforms moving with relatively large amplitudes (0.1-0.2 m). This study investigated balance...
Postural control research has focused on standing balance experiments on platforms moving with relatively large amplitudes (0.1-0.2 m). This study investigated balance strategies while standing on a platform moving 4 mm in anterior-posterior direction with frequency scaled linearly from 0.4 to 6 Hz. Platform motion and kinematic and kinetic information for nine healthy participants were recorded using motion capture and force plate systems. Coordination between hip, knee and ankle joint torque, and centre of mass (COM) and centre of pressure (COP) motion was quantified by vector coding. Significant main effect of platform frequency for knee-ankle and COP-COM phase relationship was observed (p = 0.023, p = 0.016). At frequencies below 2.11 and 2.34 Hz, ankle strategy was recruited. With ankle strategy, in-phase COP-COM motion with COP dominancy occurred at frequencies below 2.19 and 2.23 Hz during scaling up and down, respectively. As platform frequency passed these values, COM dominated over COP which was followed by anti-phase knee-ankle torque, called a knee strategy, and anti-phase motion between the COP and COM that allowed COP to regain dominance over COM. Collectively, we reveal knee strategy as a new and relevant strategy in real-life settings, and transition between ankle and knee strategies that underpinned transition between COP-COM relative motion.
Topics: Humans; Posture; Postural Balance; Biomechanical Phenomena; Ankle Joint; Ankle
PubMed: 36470936
DOI: 10.1038/s41598-022-24731-3 -
Foot & Ankle International Jan 2019Establishing score points that reflect meaningful change from the patient perspective is important for interpreting patient-reported outcomes. This study estimated the...
BACKGROUND:
Establishing score points that reflect meaningful change from the patient perspective is important for interpreting patient-reported outcomes. This study estimated the minimum clinically important difference (MCID) values of 2 Patient-Reported Outcomes Measurement Information System (PROMIS) instruments and the Foot and Ankle Ability Measure (FAAM) Sports subscale within a foot and ankle orthopedic population.
METHODS:
Patients seen for foot and ankle conditions at an orthopedic clinic were administered the PROMIS Physical Function (PF) v1.2, the PROMIS Pain Interference (PI) v1.1, and the FAAM Sports at baseline and all follow-up visits. MCID estimation was conducted using anchor-based and distribution-based methods.
RESULTS:
A total of 3069 patients, mean age of 51 years (range = 18-94), were included. The MCIDs for the PROMIS PF ranged from approximately 3 to 30 points (median = 11.3) depending on the methods being used. The MCIDs ranged from 3 to 25 points (median = 8.9) for the PROMIS PI, and from 9 to 77 points (median = 32.5) for the FAAM Sports.
CONCLUSIONS:
This study established a range of MCIDs in the PROMIS PF, PROMIS PI, and FAAM Sports indicating meaningful change in patient condition. MCID values were consistent across follow-up periods, but were different across methods. Values below the 25th percentile of MCIDs may be useful for low-risk clinical decisions. Midrange values (eg, near the median) should be used for high stakes decisions in clinical practice (ie, surgery referrals). The MCID values within the interquartile range should be utilized for most decision making.
LEVEL OF EVIDENCE:
Level I, diagnostic study, testing of previously developed diagnostic measure on consecutive patients with reference standard applied.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Ankle; Ankle Joint; Female; Foot; Humans; Male; Middle Aged; Orthopedic Procedures; Outcome Assessment, Health Care; Pain Measurement; Patient Reported Outcome Measures; Prospective Studies; ROC Curve; Recovery of Function; Reference Values; Young Adult
PubMed: 30282469
DOI: 10.1177/1071100718800304 -
The Journal of Experimental Biology Dec 2016Muscle-tendon units about the ankle joint generate a burst of positive power during the step-to-step transition in human walking, termed ankle push-off, but there is no... (Review)
Review
Muscle-tendon units about the ankle joint generate a burst of positive power during the step-to-step transition in human walking, termed ankle push-off, but there is no scientific consensus on its functional role. A central question embodied in the biomechanics literature is: does ankle push-off primarily contribute to leg swing, or to center of mass (COM) acceleration? This question has been debated in various forms for decades. However, it actually presents a false dichotomy, as these two possibilities are not mutually exclusive. If we ask either question independently, the answer is the same: yes! (1) Does ankle push-off primarily contribute to leg swing acceleration? Yes. (2) Does ankle push-off primarily contribute to COM acceleration? Yes. Here, we summarize the historical debate, then synthesize the seemingly polarized perspectives and demonstrate that both descriptions are valid. The principal means by which ankle push-off affects COM mechanics is by a localized action that increases the speed and kinetic energy of the trailing push-off limb. Because the limb is included in body COM computations, this localized segmental acceleration also accelerates the COM, and most of the segmental energy change also appears as COM energy change. Interpretation of ankle mechanics should abandon an either/or contrast of leg swing versus COM acceleration. Instead, ankle push-off should be interpreted in light of both mutually consistent effects. This unified perspective informs our fundamental understanding of the role of ankle push-off, and has important implications for the design of clinical interventions (e.g. prostheses, orthoses) intended to restore locomotor function to individuals with disabilities.
Topics: Ankle; Ankle Joint; Biomechanical Phenomena; Gait; Humans
PubMed: 27903626
DOI: 10.1242/jeb.140376 -
International Journal of Environmental... Dec 2021To investigate the effects of a 6-week integrated training program on the ankle joint reposition sense and postural stability in ballet dancers.
OBJECTIVE
To investigate the effects of a 6-week integrated training program on the ankle joint reposition sense and postural stability in ballet dancers.
METHODS
Sixteen female ballet dancers participated in the study and underwent a 6-week integrated training program consisting of plyometric, proprioception and core stability exercises along with a home program involving additional ankle muscle strengthening and stretching. The ankle joint reposition tests and the parameters of the center of pressure (COP) while performing (deep squatting) and (standing on balls of foot) movements were measured before and after training.
RESULTS
After 6 weeks, participants showed significantly smaller absolute ankle joint reposition errors in dorsiflexion ( = 0.031), plantarflexion ( = 0.003) and eversion ( = 0.019) compared to the pre-training measurement. Furthermore, after training, a significantly slower average COP speed at pre-equilibrium during movement ( = 0.003) and pre-equilibrium phase of ( = 0.023) were observed. In addition, the maximum COP displacement in the medial-lateral direction was significantly smaller at pre-equilibrium phase during ( = 0.044) and movements ( = 0.004) after training.
CONCLUSIONS
The 6-week integrated training program improved the ankle joint reposition sense and postural control in the medial-lateral direction during and movements.
Topics: Ankle; Ankle Joint; Core Stability; Dancing; Female; Foot; Humans; Postural Balance
PubMed: 34886476
DOI: 10.3390/ijerph182312751 -
Journal of Foot and Ankle Research Jun 2024The aim of this study was to compare the plantar pressure distribution and knee and ankle muscle architecture in women with and without knee osteoarthritis (OA).
BACKGROUND
The aim of this study was to compare the plantar pressure distribution and knee and ankle muscle architecture in women with and without knee osteoarthritis (OA).
METHODS
Fifty women with knee OA (mean age = 52.11 ± 4.96 years, mean Body mass index (BMI) = 30.94 ± 4.23 kg/m) and 50 healthy women as a control group (mean age = 50.93 ± 3.78 years, mean BMI = 29.06 ± 4.82 kg/m) were included in the study. Ultrasonography was used to evaluate knee and ankle muscles architecture and femoral cartilage thickness. The plantar pressure distribution was evaluated using the Digital Biometry Scanning System and Milleri software (DIASU, Italy). Static foot posture was evaluated using the Foot Posture Index (FPI), and pain severity was assessed using the Visual Analog Scale.
RESULTS
The OA group exhibited lower muscle thickness in Rectus Femoris (RF) (p = 0.003), Vastus Medialis (VM) (p = 0.004), Vastus Lateralis (p = 0.023), and Peroneus Longus (p = 0.002), as well as lower Medial Gastrocnemius pennation angle (p = 0.049) and higher Fat thickness (FT) in RF (p = 0.033) and VM (p = 0.037) compared to the control group. The OA group showed thinner femoral cartilage thickness (p = 0.001) and higher pain severity (p = 0.001) than the control groups. FPI scores were higher (p = 0.001) in OA group compared to the control group. The plantar pressure distribution results indicated an increase in total surface (p = 0.027), total load (p = 0.002), medial load (p = 0.005), and lateral load (p = 0.002) on dominant side in OA group compared to the control group.
CONCLUSIONS
Knee and ankle muscle architecture, knee extensor muscle FT, and plantar pressure distribution in the dominant foot differed in individuals with knee OA compared to the control group.
Topics: Humans; Female; Osteoarthritis, Knee; Middle Aged; Muscle, Skeletal; Pressure; Foot; Ultrasonography; Ankle Joint; Case-Control Studies; Knee Joint; Posture; Ankle
PubMed: 38820170
DOI: 10.1002/jfa2.12028 -
Sensors (Basel, Switzerland) Feb 2021This study involves measurements of bi-axial ankle stiffness in older adults, where the ankle joint is passively moved along the talocrural and subtalar joints using a...
This study involves measurements of bi-axial ankle stiffness in older adults, where the ankle joint is passively moved along the talocrural and subtalar joints using a custom ankle movement trainer. A total of 15 elderly individuals participated in test-retest reliability measurements of bi-axial ankle stiffness at exactly one-week intervals for validation of the angular displacement in the device. The ankle's range of motion was also compared, along with its stiffness. The kinematic measurements significantly corresponded to results from a marker-based motion capture system (dorsi-/plantar flexion: = 0.996; inversion/eversion: = 0.985). Bi-axial ankle stiffness measurements showed significant intra-class correlations (ICCs) between the two visits for all ankle movements at slower (2.14°/s, ICC = 0.712) and faster (9.77°/s, ICC = 0.879) speeds. Stiffness measurements along the talocrural joint were thus shown to have significant negative correlation with active ankle range of motion ( = -0.631, = 0.012). The ankle movement trainer, based on anatomical characteristics, was thus used to demonstrate valid and reliable bi-axial ankle stiffness measurements for movements along the talocrural and subtalar joint axes. Reliable measurements of ankle stiffness may help clinicians and researchers when designing and fabricating ankle-foot orthosis for people with upper-motor neuron disorders, such as stroke.
Topics: Aged; Ankle; Ankle Joint; Biomechanical Phenomena; Humans; Range of Motion, Articular; Reproducibility of Results; Subtalar Joint
PubMed: 33562234
DOI: 10.3390/s21041162 -
Knee Surgery, Sports Traumatology,... Dec 2022Different graft options are available for the reconstruction of lateral ankle ligaments to treat chronic ankle instability (CAI), which fall in two categories:... (Review)
Review
PURPOSE
Different graft options are available for the reconstruction of lateral ankle ligaments to treat chronic ankle instability (CAI), which fall in two categories: allografts and autografts. This study aims to provide an updated comparison of the clinical outcomes after stabilisation procedures using allografts and autografts, to correctly advise the clinician during the choice of the best material to be used for the reconstruction of the lateral ligamentous complex of the ankle.
METHODS
A systematic review was performed to analyse the use of autografts and allografts for anatomic reconstruction of the lateral ligamentous complex of the ankle in CAI patients. The presence of a postoperative assessment through outcome measures with proofs of validation in the CAI population or patient's subjective evaluation on the treatment were necessary for inclusion. The quality of the included studies was assessed through the modified Coleman Methodology Score (mCMS). Relevant clinical outcome data were pooled to provide a synthetic description of the results in different groups or after different procedures.
RESULTS
Twenty-nine studies (autograft: 19; allograft: 9; both procedures: 1) accounting for 930 procedures (autograft: 616; allograft: 314) were included. The average mCMS was 55.9 ± 10.5 points. The Karlsson-Peterson scale was the most frequently reported outcome scale, showing a cumulative average post- to preoperative difference of 31.9 points in the autograft group (n = 379, 33.8 months follow-up) and of 35.7 points in the allograft group (n = 227, 25.8 months follow-up). Patient satisfaction was good or excellent in 92.8% of autograft (n = 333, 65.2 months follow-up) and in 92.3% of allograft procedures (n = 153, 25.0 months follow-up). Return to activity after surgery and recurrence of instability were variably reported across the studies with no clear differences between allograft and autograft highlighted by these outcomes.
CONCLUSIONS
The systematic analysis of validated CAI outcome measures and the patient's subjective satisfaction does not support a specific choice between autograft and allograft for the reconstruction of the ankle lateral ligamentous complex in CAI patients. Both types of grafts were associated to a postoperative Karlsson-Peterson score superior to 80 points and to a similar rate of patient's subjective satisfaction.
LEVEL OF EVIDENCE
Level IV.
Topics: Humans; Ankle; Allografts; Lateral Ligament, Ankle; Joint Instability; Ankle Joint; Autografts
PubMed: 35916928
DOI: 10.1007/s00167-022-07071-7 -
Medicine Sep 2022Functional ankle instability (FAI) is defined as the subjective sensation of instability or "giving way" after an ankle sprain and occurs in approximately 40% of...
BACKGROUND
Functional ankle instability (FAI) is defined as the subjective sensation of instability or "giving way" after an ankle sprain and occurs in approximately 40% of patients with lateral ankle instability. As an ankle joint rehabilitation intervention, heel raising exercises, toe jumping exercises, ankle joint proprioceptive exercises, as well as orthosis and taping are commonly applied to prevent the recurrence of an ankle joint injury. So this study was evaluated effect of quarter heel raising exercise (QHR) on balance and peroneus longus muscle strength in FAI subjects.
METHODS
Among 26 FAI subjects, 13 with FAI were assigned to the QHR group, and 13 with FAI were assigned to the control group which was no intervention. All of 30 subjects were evaluated Teskscan included static balance ability, Y balance test included dynamic balance ability with three directions which is anterior, posterolateral, posteromedial direction. Commander muscle testing included eversion/inversion strength ratio at pre- and post-intervention.
RESULTS
There was a significant interaction between group and time in static, dynamic balance, and strength. In QHR group, there was simple effect on static, dynamic balance, and strength. But control group showed no simple effect on static, dynamic balance, and strength. In the pre- and post-intervention differences between the groups. There was a significant difference in pre-intervention condition between the groups, but no significant difference between the groups in post-intervention in all conditions.
CONCLUSIONS
QHR exercise is useful for improving the balance ability and muscle strength of the peroneus longus muscle in FAI subjects.
Topics: Ankle; Ankle Injuries; Ankle Joint; Heel; Humans; Joint Instability; Postural Balance
PubMed: 36197155
DOI: 10.1097/MD.0000000000030672