The effect of ankle Kinesio™ taping on ankle joint biomechanics during unilateral balance status among collegiate athletes with chronic ankle sprain

ObjectivesTo determine the effects of ankle Kinesio-taping (KT) on postural sway, lower limb ROM, and muscle activity during a unilateral balance tasks.DesignCase control study design.SettingData were collected at the human movement analysis laboratory.Participants30 collegiate athletes with chronic ankle sprain (11 females and 19 males, 23.91 ± 2.58 years).Main outcome measureHip, knee and ankle joints ranges of motion (ROMs); postural sway area and velocities in both anteroposterior and mediolateral directions; and muscular activity amplitudes (% peak) of lateral and medial gastrocnemius, tibialis anterior and peroneus longus in a 20s single leg balance test in two non-taped (control) and KT (intervention) conditions.ResultsSignificant decrease observed in ankle lateral ROM (p = 0.048, d = 0.52), mediolateral postural sway velocity (p = 0.029, d = 1.25), and peroneus longus activity amplitudes (p = 0.042, d = 0.55) after KT application.ConclusionAcute application of KT among athletes with chronic ankle instability could provide lateral mechanical support to the ankle, potentially decreasing the velocity of frontal plane sway, and decreasing the magnitude of muscle activation. These data suggest that KT may be beneficial for improving static joint stability among individuals with chronic ankle sprain, and thus could be considered an option to allow safe return-to-activity.     

Single-leg drop landing movement strategies in participants with chronic ankle instability compared with lateral ankle sprain ‘copers’

Purpose

To compare the movement patterns and underlying energetics of individuals with chronic ankle instability (CAI) to ankle sprain ‘copers’ during a landing task.

Methods

Twenty-eight (age 23.2 ± 4.9 years; body mass 75.5 ± 13.9 kg; height 1.7 ± 0.1 m) participants with CAI and 42 (age 22.7 ± 1.7 years; body mass 73.4 ± 11.3 kg; height 1.7 ± 0.1 m) ankle sprain ‘copers’ were evaluated 1 year after incurring a first-time lateral ankle sprain injury. Kinematics and kinetics of the hip, knee and ankle joints from 200 ms pre-initial contact (IC) to 200 ms post-IC, in addition to the vertical component of the landing ground reaction force, were acquired during performance of a drop land task.

Results

The CAI group adopted a position of increased hip flexion during the landing descent on their involved limb. This coincided with a reduced post-IC flexor pattern at the hip and increased overall hip joint stiffness compared to copers (?0.01 ± 0.05 vs 0.02 ± 0.05°/Nm kg^?1, p = 0.03).

Conclusions

Individuals with CAI display alterations in hip joint kinematics and energetics during a unipodal landing task compared to LAS ‘copers’. These alterations may be responsible for the increased risk of injury experienced by individuals with CAI during landing manoeuvres. Thus, clinicians must recognise the potential for joints proximal to the affected ankle to contribute to impaired function following an acute lateral ankle sprain injury and to develop rehabilitation protocols accordingly.

Level of evidence

Level III.

     

Anterior ankle arthroscopy, distraction or dorsiflexion?

Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7–1.5) and 0.7 cm (range 0.5–0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy.     

Effects of total knee arthroplasty on ankle alignment in patients with varus gonarthrosis: Do we sacrifice ankle to the knee?

Purpose

Total knee arthroplasty is one of the most commonly preferred surgical methods in the treatment of patients with varus gonarthrosis. In this study, we aimed to evaluate the radiological changes observed in the ankles after total knee arthroplasty.

Methods

Between May 2012 and June 2013, 80 knees of 78 patients with varus deformity over 10° underwent total knee arthroplasty. For each patient, full-leg standing radiographs were obtained pre- and post-operatively. Mechanical and anatomical axes (HKA and AA), lateral distal femoral angle, medial proximal tibial angle, lateral distal tibial angle (LDTA), ankle joint line orientation angle (AJOA), tibial plafond talus angle (PTA) and talar shift were measured for each patient both pre- and post-operatively.

Results

Pre-operatively, the mean HKA was 16.6° and the mean AA was 10.41°, both in favour of varus alignment. Post-operatively, the mean HKA decreased to 3.6° and the mean AA to ?2.1. The mean LDTA was 87.3°. Before the operation, the mean AJOA was ?7.6°, opening to the medial aspect of the ankle, and it was 0.04° after the operation and opening to the lateral aspect (p < 0.05).

Conclusion

Our study reveals the changes occurring in the ankle after acute correction of long-standing varus deformity of the knee using total knee arthroplasty. In cases undergoing knee arthroplasty, effect of the acute change in the alignment of the knee on the ankle should be taken into consideration and the amount of correction should be calculated carefully in order not to damage the alignment of the ankle.

Level of evidence

IV.

     

Does stretching increase ankle dorsiflexion range of motion? A systematic review

Background

Many lower limb disorders are related to calf muscle tightness and reduced dorsiflexion of the ankle. To treat such disorders, stretches of the calf muscles are commonly prescribed to increase available dorsiflexion of the ankle joint.

Hypothesis

To determine the effect of static calf muscle stretching on ankle joint dorsiflexion range of motion.

Study design

A systematic review with meta‐analyses.

Methods

A systematic review of randomised trials examining static calf muscle stretches compared with no stretching. Trials were identified by searching Cinahl, Embase, Medline, SportDiscus, and Central and by recursive checking of bibliographies. Data were extracted from trial publications, and meta‐analyses performed that calculated a weighted mean difference (WMD) for the continuous outcome of ankle dorsiflexion. Sensitivity analyses excluded poorer quality trials. Statistical heterogeneity was assessed using the quantity I².

Results

Five trials met inclusion criteria and reported sufficient data on ankle dorsiflexion to be included in the meta‐analyses. The meta‐analyses showed that calf muscle stretching increases ankle dorsiflexion after stretching for ⩽15 minutes (WMD 2.07°; 95% confidence interval 0.86 to 3.27), >15–30 minutes (WMD 3.03°; 95% confidence interval 0.31 to 5.75), and >30 minutes (WMD 2.49°; 95% confidence interval 0.16 to 4.82). There was a very low to moderate statistical heterogeneity between trials. The meta‐analysis results for ⩽15 minutes and >15–30 minutes of stretching were considered robust when compared with sensitivity analyses that excluded lower quality trials.

Conclusions

Calf muscle stretching provides a small and statistically significant increase in ankle dorsiflexion. However, it is unclear whether the change is clinically important.     

High resolution ultrasonography in ankle joint pain: Where does it stand?

Background

The ankle is frequently injured in trauma, overuse syndrome and inflammatory processes. Different imaging modalities assess the ankle, including plain radiography, computed tomography (CT), magnetic resonance imaging (MRI), and ultrasonography (US).

Bone anchors or interference screws? A biomechanical evaluation for autograft ankle stabilization

BACKGROUND: Autograft stabilization uses free semitendinosus tendon grafts to anatomically reconstruct the anterior talofibular ligament. Study aims were to evaluate the biomechanical properties of Mitek GII anchors compared with the Arthrex Bio-Tenodesis Screw for free tendon reconstruction of the anterior talofibular ligament. NULL HYPOTHESIS: There are no differences in load to failure and percentage specimen elongation at failure between the 2 methods. STUDY DESIGN: Controlled laboratory study using porcine models. METHODS: Sixty porcine tendon constructs were failure tested. Re-creating the pull of the anterior talofibular ligament, loads were applied at 70 degrees to the bones. Thirty-six tendons were fixed to porcine tali and tested using a single pull to failure; 10 were secured with anchors and No. 2 Ethibond, 10 with anchors and FiberWire, 10 with screws and Fiberwire, and 6 with partially gripped screws. Cyclic preloading was conducted on 6 tendons fixed by anchors and on 6 tendons fixed by screws before failure testing. Two groups of 6 components fixed to the fibula were also tested. RESULTS: The talus single-pull anchor group produced a mean load of 114 N and elongation of 37% at failure. The talus single-pull screw group produced a mean load of 227 N and elongation of 22% at failure (P <.05). Cyclic preloading at 65% failure load before failure testing produced increases in load and decreases in elongation at failure. Partially gripped screws produced a load of 133 N and elongation of 30% at failure. The fibula model produced significant increases in load to failure for both. The human anterior talofibular ligament has loads of 139 N at failure with instability occurring at 20% elongation. CONCLUSIONS: Interference screw fixation produced significantly greater failure strength and less elongation at failure than bone anchors. Clinical Relevance: The improved biomechanics of interference screws suggests that these may be more suited to in vivo reconstruction of the anterior talofibular ligament than are bone anchors.     

Anterior–posterior mobility of the talus in subjects with chronic ankle instability

ObjectivesThe effect of hypermobility or hypomobility of the talus in subjects with chronic ankle instability (CAI) has not been fully elucidated. The purpose of this study was to determine the anterior–posterior mobility of the talus in subjects with CAI.DesignRetrospective case–control study.SettingAthletic training research laboratory.ParticipantsFifteen subjects with unilateral CAI, and 15 subjects with no previous history of ankle injury participated in this study.Main outcomes measuresAnterior talar laxity was assessed with manual anterior drawer test and anterior drawer stress radiographs. Posterior talar hypomobility was assessed with a series of two posterior talar glide manual tests. Comparisons were made between the CAI and control groups and within sides of both groups.ResultsThe CAI group (mean=11.4±5.4 mm) had significantly more anterior talar displacement on both their ankles as measured on the stress views than did the control group (mean=6.7±4.7 mm). Interestingly, there was very little side to side difference between the involved and uninvolved ankles of the CAI group (11.5±5.6 vs. 11.3±5.4 mm). There were no significant differences involving either of the posterior talar glide measures or of the manual anterior drawer test.ConclusionsAn increased amount of anterior talar mobility was demonstrated in the CAI group. Although all of our subjects reported unilateral CAI, increased laxity was present in both their unstable and healthy ankles.     

Comparison of modified Broström and Evans procedures in simulated lateral ankle injury

PURPOSE: The purpose of this study was to compare the modified Brostr?m and Evans procedures for simulated lateral ankle instability in cadaveric lower extremities. METHODS: Six normal cadaveric ankles were loaded with inversion and internal rotation stress through the range of ankle flexion, and three-dimensional motion of the calcaneus and talus relative to the tibia were measured. An ankle stability testing device and a magnetic tracking system were used. Testing was performed in the intact condition, unstable condition after sectioning both the anterior talofibular (ATFL) and calcaneofibular ligaments (CFL), after the Gould modification of the Brostr?m procedure, and after the Evans procedure. RESULTS: With inversion loading, both operations resulted in a significantly more stable ankle-hindfoot complex (calcaneal-tibial) than the unstable condition, but there was restricted motion after the Evans operation from neutral to plantarflexion. Tibiotalar inversion motion approximated normal after both operations, but subtalar motion was markedly restricted in the Evans procedure throughout the range of ankle flexion. With internal rotation loading, the Brostr?m operation stabilized the ankle-hindfoot joint complex in plantarflexion. The Evans operation improved internal rotation stability, but restricted motion in all positions. Both operations improved tibiotalar internal rotation stability, but not to normal. The subtalar internal rotation was the same as the intact condition after the Brostr?m operation, but markedly restricted after the Evans operation through the range of ankle flexion. CONCLUSIONS: Both operations improved ankle-hindfoot stability, but neither was successful in restoring it to normal as determined with the ankle stability testing device. The Evans procedure improved stability at the expense of creating abnormal subtalar function. The Brostr?m operation improved stability without excessively restricting subtalar movement, but was not effective in addressing the internal rotation laxity.     

Bone bruises associated with acute ankle ligament injury: do they need treatment?

Purpose

The aim of this systematic review is to analyse the current knowledge, incidence, relevance, and need for treatment of bone bruises associated with acute ankle ligament injury.

Methods

A search was made of PubMed, OVID/Medline, Cochrane databases using the keyword “bone bruises” in combination with “ankle”, “sprain”, “management”, “surgery”, and “conservative treatment”.

Results

No randomized controlled trials or prospective cohort studies were found. Only case series were retrieved. A critical appraisal for validity and usefulness of the studies revealed that the best level of evidence on this topic is represented by retrospective comparative studies. Nine studies evaluating the management of bone bruises associated with acute ankle ligament injuries were found.

Conclusion

The clinical prognosis of bone bruises is generally good, with a normalization of MRI appearance usually within 6–12 months after trauma. Currently, there is no evidence that these lesions need specific treatment. Thus, the management of the concomitant ligament lesions is sufficient. Further research is necessary to successfully address the management of bone bruises, and more evidence is required to decide if these lesions need to be treated at all.

Level of evidence

IV.     

Physiological coxa varus–genu valgus influences internal knee and ankle joint moments in females during crossover cutting

This study evaluated the ankle and knee electromyographic, kinematic, and kinetic differences of 20 nonimpaired females with either neutral (group 1) or coxa varus–genu valgus (group 2) alignment during crossover cutting stance phase. Two-way mixed model ANOVA (group, session) assessed mean differences (p<0.05) and correlation analysis further delineated relationships. During impact absorption, group 2 displayed earlier peak horizontal braking (anterior-posterior) ground reaction force timing, decreased and earlier peak internal knee extension moments (eccentric function), and earlier peak internal ankle dorsiflexion moment timing (eccentric function). During the pivot phase, group 2 displayed later and eccentrically-biased peak ankle plantar flexion moments, increased peak internal knee flexion moments (eccentric function), and later peak knee internal rotation timing. Correlation analysis revealed that during impact absorption, subjects with coxa varus–genu valgus alignment (group 2) displayed a stronger relationship between knee internal rotation velocity and peak internal ankle dorsiflexion moment onset timing (r=–0.64 vs r =–0.26) and between peak horizontal braking ground reaction forces and peak internal ankle dorsiflexion moment onset timing (r=0.61 vs r=0.24). During the pivot phase these subjects displayed a stronger relationship between peak horizontal braking ground reaction forces and peak internal ankle plantar flexion moment onset timing (r=–0.63 vs r=–0.09) and between peak horizontal braking forces and peak internal ankle plantar flexion moments (r=–0.72 vs r=–0.26). Group differences suggest that subjects with coxa varus–genu valgus frontal-plane alignment have an increased dependence on both ankle dorsiflexor and plantar flexor muscle group function during crossover cutting. Greater dependence on ankle muscle group function during the performance of a task that requires considerable 3D dynamic knee joint control suggests a greater need for frontal and transverse plane weight bearing tasks that facilitate eccentric ankle muscle group function to optimize injury prevention conditioning and post-surgical rehabilitation programs.     

Mechanical energy profiles of the combined ankle–foot system in normal gait: Insights for prosthetic designs

Over the last half-century, the field of prosthetic engineering has continuously evolved with much attention being dedicated to restoring the mechanical energy properties of ankle joint musculatures during gait. However, the contributions of ‘distal foot structures’ (e.g., foot muscles, plantar soft tissue) have been overlooked. Therefore, the purpose of this study was to quantify the total mechanical energy profiles (e.g., power, work, and work-ratio) of the natural ankle–foot system (NAFS) by combining the contributions of the ankle joint and all distal foot structures during stance in level-ground steady state walking across various speeds (0.4, 0.6, 0.8 and 1.0 statures/s). The results from eleven healthy subjects walking barefoot indicated ankle joint and distal foot structures generally performed opposing roles: the ankle joint performed net positive work that systematically increased its energy generation with faster walking speeds, while the distal foot performed net negative work that systematically increased its energy absorption with faster walking speeds. Accounting for these simultaneous effects, the combined ankle–foot system exhibited increased work-ratios with faster walking. Most notably, the work-ratio was not significantly greater than 1.0 during the normal walking speed of 0.8 statures/s. Therefore, a prosthetic design that strategically exploits passive-dynamic properties (e.g., elastic energy storage and return) has the potential to replicate the mechanical energy profiles of the NAFS during level-ground steady-state walking.     

Changes in muscle activity in children with hemiplegic cerebral palsy while walking with and without ankle–foot orthoses

We compared the electromyographic (EMG) signals of lower extremity muscle groups in 10 children with hemiplegic cerebral palsy (CP) while walking barefoot and in a hinged ankle–foot orthosis (HAFO). All children had excessive plantarflexion and initial toe-contact on the affected side when walking barefoot, a typical gait pattern for hemiplegic patients. The patients walked with a physiological heel–toe gait pattern when wearing the HAFO. The peak activity of the tibialis anterior muscle was reduced by 36.1% at initial contact and loading response phase and by 57.3% just after toe-off when using a HAFO. The decrease in activity was thought to result from the change in gait pattern from a toe-gait to a heel–toe gait as well as the use of a HAFO. The HAFO also slightly decreased muscle activity in the proximal leg muscles mainly during swing phase, improved stride length, decreased cadence, improved walking speed, increased peak hip flexion, improved kinematics in loading response phase at the knee, and reduced the excessive ankle plantarflexion.     

Compensatory sagittal plane ankle gait mechanics: Are they present in patients with a weak or stiff hip?

IntroductionSimulations suggest that subjects with reduced hip range of motion (ROM) and/or weakness can achieve more normal walking mechanics through compensations at the ankle. The aims of this study were to assess whether subjects with reduced hip ROM (Stiff hip) or hip flexor weakness (Weak hip) exhibit ankle compensations during walking and investigate redistribution of power in the lower extremity joints.MethodsRetrospective gait data were reviewed (IRB-approved hip registry). Preoperative kinematic/kinetic walking data were collected in patients with: adolescent hip dysplasia (AHD), femoral acetabular impingement (FAI), and Legg-Calvé Perthes disease (Perthes). AHD patients with significantly weak hip flexors on their affected side were included (Weak hip group). The Gait Profile Score (GPS) was calculated on the affected side of the FAI and Perthes groups to identify patients who had a Stiff hip. Patients who had undergone a hip arthrodesis (Fusion) were also included (Stiff hip group). Ankle kinematics/kinetics were compared to healthy participants (Control). The total positive work of sagittal plane hip, knee and ankle power were compared along with the distribution of power.ResultsPatients in the Weak/Stiff hip groups did not walk with greater ankle plantarflexion, peak push-off power or positive ankle work on their affected sides compared to Control. Ankle work contribution (percentage of total positive work) on the affected or unaffected sides was greater in the Perthes and Hip Fusion patients compared to Control. Significant gait abnormalities on the unaffected side were observed.ConclusionsPatients with a weak or stiff hip did exhibit altered ankle mechanics during walking. Greater percent ankle work contribution appeared to correspond with hip stiffness. In patients with hip pathology the redistribution of power among the lower extremity joints can highlight the importance of preserving ankle function.