Talar Positional Fault in Persons With Chronic Ankle Instability

Ultrasonography assessments of talar cartilage and ATFL after running in chronically unstable, coper, and healthy ankles: a case-control study

BACKGROUND

Comparisons of talar cartilage and the anterior talofibular ligament (ATFL) profiles in individuals with different levels of chronic ankle instability (CAI) provide insight into early adaptation of tissue morphology.

PURPOSE

This study compared morphologic response and recovery of the talar cartilage and ATFL before and after 30-min of self-paced treadmill running between individuals with CAI, coper (full recovery from a first-time ankle sprain), and healthy controls.

METHODS

Sixty young males (24.8 years, 176.9 cm, 75.7 kg) were allocated into the CAI, coper, and healthy control group by their number of ankle sprains and scores on the self-reported ankle instability questionnaires (Cumberland Ankle Instability Tool, and Foot and Ankle Ability Measure-Activities of Daily Living). Ultrasonographic images in the cross-sectional area (CSA; overall, lateral, and medial) and ATFL length (unstressed and stressed and position) before and after treadmill running were recorded and analyzed.

RESULTS

There were no group by time interactions in the talar cartilage CSA (F14,399 <1.09, p > .36 for all tests) and ATFL length (F14,399< .69, p > .79 for all tests). Regardless of time, CAIs had the largest overall (F2,399 = 42.68, p < .001), lateral (F2,399 = 37.16, p < .001), and medial (F2,399 = 36.57, p < .001) CSA of talar cartilage and the longest stressed-ATFL length (F2,399 = 54.42, p < .001), followed by copers and healthy controls.

CONCLUSION

Morphologic features of the talar cartilage and ATFL appear to depend on the level of ankle instability (e.g. a history of recurrent ankle sprain).

Lower limb squat biomechanics and select clinical measures in chronic ankle instability

BACKGROUND

Individuals with chronic ankle instability often present with clinical and biomechanical abnormalities, however squat biomechanics have not been investigated. The purpose of this study was to compare select clinical assessments and squat biomechanics between individuals with and without chronic ankle instability.

METHODS

Fifteen individuals with chronic ankle instability and a matched control group were studied. A weight-bearing dorsiflexion lunge test, foot posture, and an in-line half-kneeling motor control test for core stability were assessed. Lower limb 3D bilateral and unilateral squat biomechanics were captured. Groups, limbs and squat tasks were compared using an alpha of 0.05.

FINDINGS

Individuals with chronic ankle instability had less static weight-bearing dorsiflexion and failed the core stability test more frequently, but did not differ in foot morphology compared to the controls. When squatting, those with chronic ankle instability demonstrated reduced peak ankle dorsiflexion angles and moments in the involved limb (p < 0.04) during single limb squats and had interlimb differences in ankle dorsiflexion angle as well as hip and knee kinetics (p < 0.04) during double limb squats. In those with chronic ankle instability, there was less overall motion, but higher kinetic demands in single limb versus double leg squatting (p < 0.03).

INTERPRETATION

Individuals with chronic ankle instability had impaired weight-bearing dorsiflexion and showed impaired core stability more often, which accompanied altered squatting mechanics in both variations. Within the limbs with chronic ankle instability, single limb squats showed lesser kinematic demands but higher kinetic demands than double limb squatting.

Using clinician-oriented and laboratory-oriented assessments to study dynamic stability of individuals with chronic ankle instability

To compare the dynamic stability of lower extremities between Copers and individuals with chronic ankle instability (CAI) using clinician-oriented assessments (Y-balance test, YBT) and laboratory-oriented assessments (time to stabilization, TTS). 90 participants (Copers, 45; CAIs, 45) were recruited and measured by YBT and TTS to evaluate dynamic stability. The difference of dynamic stability between Copers and CAIs was examined using a two-factor MANOVA. Only for females in anterior direction, YBT scores for the AS side of Copers were significantly higher than that of CAIs. For males, the TTS of CAIs was significantly shorter than that of Copers in the anterior, lateral, and medial direction separately. For females, the TTS of CAIs is also significantly shorter than that of Copers in the anterior, lateral, and medial direction separately. There are opposite results when evaluating the dynamic stability difference between Copers and CAIs using YBT and TTS.

Assessments Used by Athletic Trainers to Decide Return-to-Activity Readiness in Patients With an Ankle Sprain

CONTEXT

Athletic trainers (ATs) often care for patients with ankle sprains. Expert consensus has been established for rehabilitation-oriented assessments (ROASTs) that should be included in ankle-sprain evaluations. However, the methods ATs use to determine return-to-activity readiness after an ankle sprain are unknown.

OBJECTIVES

To identify ATs' methods for determining patients' return-to-activity readiness after an ankle sprain and demographic characteristics of the ATs and their methods.

SETTING

Online survey.

DESIGN

Cross-sectional study.

PATIENTS OR OTHER PARTICIPANTS

We recruited 10 000 clinically practicing ATs. A total of 676 accessed the survey, 574 submitted responses (85% completion rate), and 541 respondents met the inclusion criteria.

MAIN OUTCOME MEASURE(S)

We distributed an online survey to ATs that asked about their assessment of pain, swelling, range of motion, arthrokinematics, strength, balance, gait, functional capacity, physical activity level, and patient-reported outcomes in deciding return to activity. Descriptive statistics were used to characterize participant demographics and frequencies of the assessment measures used by ATs. Chi-square analysis was conducted to identify relationships between the demographics and assessment selection.

RESULTS

Pain, swelling, range of motion, strength, balance, gait, and functional capacity were assessed by 76.2% to 96.7% of ATs. Arthrokinematics, physical activity level, and patient-reported outcomes were assessed by 25.3% to 35.1% of participants. When selecting specific assessment methods, ATs often did not use recommended ROASTs. Athletic trainers with higher degrees, completion of more advanced educational programs, employment in nontraditional settings, more clinical experience, and familiarity with expert consensus recommendations were more likely to use ROASTs.

CONCLUSIONS

Before approving return to activity for patients with ankle sprains, ATs did not use some recommended outcomes and assessment methods. Practice in nontraditional settings, more advanced degrees, more clinical experience, and familiarity with expert consensus guidelines appeared to facilitate the use of ROASTs.

Evaluation of arthrokinematics and posterior soft tissues of the ankle during ankle dorsiflexion using ultrasound

BACKGROUND

Arthrokinematics (caudal and posterior movements of the talus) and posterior soft tissues of the ankle during ankle dorsiflexion have not been objectively evaluated in detail. This study aimed to investigate the characteristics of arthrokinematics and posterior soft tissues of the ankle during ankle dorsiflexion using ultrasound.

METHODS

Thirteen healthy adults participated in the study. Participants whose passive dorsiflexion range of motion (ROM) of the ankle joint was <35° were classified as the restricted group (n = 6), and participants whose passive ankle dorsiflexion ROM was ≥35° were classified as the control group (n = 7). Passive ankle dorsiflexion was performed to measure the ankle arthrokinematics. Strain elastography was performed to measure the elasticity of the flexor hallucis longus (FHL) and Kager's fat pad (KFP) at each dorsiflexion angle.

RESULTS

A significant difference in the posterior movement of the talus at the ankle dorsiflexion of 30° was observed between the two groups (P = 0.04). The elasticity of the restricted group was increased at all angles in both FHL and KFP (P < 0.05).

CONCLUSION

This study showed that it is possible to objectively evaluate the direction of ankle arthrokinematics and posterior ankle soft-tissue restrictions using ultrasound.

Ankle Sprain and Chronic Lateral Ankle Instability: Optimizing Conservative Treatment

The management protocol for each case of ankle sprain should be individualized and optimized in order to reduce the likelihood of development of chronic instability. Initial treatment aims to address pain, swelling, and inflammation and facilitates regaining pain-free joint motion. Short-term joint immobilization is indicated in severe cases. Subsequently, muscle strengthening, balance training, and targeted activities to develop proprioception are added. Gradually, sports-related activities are added with the ultimate goal of bringing the individual back to preinjury level of activity. This protocol of conservative treatment should always be offered before considering any surgical intervention.

Mechanical and Sensorimotor Outcomes Associated With Talar Cartilage Deformation After Static Loading in Those With Chronic Ankle Instability

CONTEXT

Those with chronic ankle instability (CAI) demonstrate deleterious changes in talar cartilage composition, resulting in alterations of talar cartilage loading behavior. Common impairments associated with CAI may play a role in cartilage behavior in response to mechanical loading.

OBJECTIVE

To identify mechanical and sensorimotor outcomes that are linked with the magnitude of talar cartilage deformation after a static loading protocol in patients with and those without CAI.

DESIGN

Cross-sectional study.

SETTING

Laboratory setting.

PATIENTS OR OTHER PARTICIPANTS

Thirty individuals with CAI and 30 healthy individuals.

MAIN OUTCOME MEASURES(S)

After a 60-minute off-loading period, ultrasonographic images of the talar cartilage were acquired immediately before and after a 2-minute static loading protocol (single-legged stance). Talar cartilage images were obtained and manually segmented to enable calculation of medial, lateral, and overall average talar thickness. The percentage change, relative to the average baseline thickness, was used for further analysis. Mechanical (ankle joint laxity) and sensorimotor (static balance and Star Excursion Balance Test) outcomes were captured. Partial correlations were computed to determine associations between cartilage deformation magnitude and the mechanical and sensorimotor outcomes after accounting for body weight.

RESULTS

In the CAI group, greater inversion laxity was associated with greater overall (r = -0.42, P = .03) and medial (r = -0.48, P = .01) talar cartilage deformation after a 2-minute static loading protocol. Similarly, poorer medial-lateral static balance was linked with greater overall (r = 0.47, P = .01) and lateral (r = 0.50, P = .01) talar cartilage deformation. In the control group, shorter posterolateral Star Excursion Balance Test reach distance was associated with greater lateral cartilage deformation (r = 0.42, P = .03). No other significant associations were observed.

CONCLUSIONS

In those with CAI, inversion laxity and poor static postural control were moderately associated with greater talar cartilage deformation after a 2-minute static loading protocol. These results suggest that targeting mechanical instability and poor balance in those with CAI via intervention strategies may improve how the talar cartilage responds to static loading conditions.

The Effect of Manual Therapy Plus Exercise in Patients with Lateral Ankle Sprains: A Critically Appraised Topic with a Meta-Analysis

A high percentage of patients with lateral ankle sprains report poor outcomes and persistent neuromuscular impairment leading to chronic ankle instability and re-injury. Several interventions have been proposed and investigated, but the evidence on manual therapy combined with therapeutic exercise for pain reduction and functional improvement is still uncertain. The purpose was to study the effectiveness of adding manual therapy to therapeutic exercise in patients with lateral ankle sprains through a critically appraised topic. The literature search was performed in PubMed, PEDro, EMBASE and CINAHL databases, and only randomized clinical trials were included according to following criteria: (1) subjects with acute episodes of lateral ankle sprains, (2) administered manual therapy plus therapeutic exercise, (3) comparisons with therapeutic exercise alone and (4) reported outcomes for pain and function. Three randomized clinical trials (for a total of 180 patients) were included in the research. Meta-analyses revealed that manual therapy plus exercise was more effective than only exercises in improving dorsal (MD = 8.79, 95% CI: 6.81, 10.77) and plantar flexion (MD = 8.85, 95% CI 7.07, 10.63), lower limb function (MD = 1.20, 95% CI 0.63, 1.77) and pain (MD = -1.23; 95% IC -1.73, -0.72). Manual therapy can be used with therapeutic exercise to improve clinical outcome in patients with lateral ankle sprains.

Throwing Injury Prevention Strategies with a Whole Kinetic Chain-Focused Approach

Purpose of Review

This review examines the relationship between the baseball pitching motion and the kinetic chain. The goal was to determine the underlying causes of a deficiency in throwing mechanics throughout a throwing motion, and to provide an evidence-based approach on how to prevent injuries caused by a lack of proper mechanics. In doing so, we sought to provide a warm-up strategy that can be added to every baseball player’s daily on-field routine that is tailored to each phase of the throwing motion.

Recent Findings

To help minimize the risk of injury to overhead throwing athletes, a thorough understanding of the throwing motion is critical. Throwing a ball places extreme stress on the body, notably the shoulder and elbow joints. With a clear understanding of the biomechanics of throwing, we can develop an injury prevention routine to minimize unnecessary stresses throughout the kinetic chain.

Summary

The throwing cycle is a complex motion that places various stresses throughout the thrower’s body, from the ankle to the core, and from the back to the shoulder and elbow. A thorough understanding of the mechanics of this motion, along with specific exercises to target the specific actions of each phase, may allow for throwers, regardless of their age and experience, to minimize injury risk.

Abnormalities of foot and ankle alignment in individuals with chronic ankle instability: a systematic review

Background

To prevent recurrent ankle sprain, it is important to clarify the pathology of chronic ankle instability (CAI). An association has been reported between CAI and abnormalities of foot posture and ankle alignment. There is no consensus on the types of these abnormalities that occur in individuals with CAI. The objective of this systematic review is to clarify the relevance of abnormality of foot posture and ankle alignment for CAI.

Methods

A systematic computerized literature search was performed of the PubMed, CINAHL, SPORTDiscus, Web of Science, and the Cochrane Register of Clinical Trials databases. The selected studies either compared CAI patients with a control group or CAI ankles with contralateral healthy ankles and specifically reported foot posture and alignment of the ankle in the outcomes. They were written in English and published prior to June 2021. The methodological quality of the included studies was evaluated using a 16-question index. Data were extracted independently by two reviewers, and the certainty of evidence was assessed using GRADE approach.

Results

Sixteen studies including 872 patients of high to low methodological quality were included. These showed there was significant anterior displacement and internal rotation of the talus in CAI ankles (low evidence), but there was no consensus on fibular alignment or foot posture.

Conclusions

This review showed there was significant anterior displacement and internal rotation of the talus in CAI ankles but found no consensus on the characteristics of fibular and foot alignment. Further investigations are required to clarify the characteristic foot and ankle malalignment in CAI to facilitate the development of efficient interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04537-6.

Identifying Range-of-Motion Deficits and Talocrural Joint Laxity After an Acute Lateral Ankle Sprain

CONTEXT

Approximately 72% of patients with an ankle sprain report residual symptoms 6 to 18 months later. Although 44% of patients return to activity in less than 24 hours after experiencing a sprain, residual symptoms should be evaluated in the long term to determine if deficits exist. These residual symptoms may be due to the quality of ligament tissue and motion after injury.

OBJECTIVE

To compare mechanical laxity of the talocrural joint and dorsiflexion range of motion (DFROM) over time (24 to 72 hours, 2 to 4 weeks, and 6 months) after an acute lateral ankle sprain (LAS).

DESIGN

Cross-sectional study.

SETTING

Athletic training research laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 108 volunteers were recruited. Fifty-five participants had an acute LAS and 53 participants were control individuals without a history of LAS.

MAIN OUTCOME MEASURE(S)

Mechanical laxity (talofibular interval and anterior talofibular ligament length) was measured in inversion (INV) and via the anterior drawer test. The weight-bearing lunge test was conducted and DFROM was measured. The data were analyzed using repeated-measures analysis of variance, independent-samples t tests, and 1-way analysis of variance.

RESULTS

Of the 55 LASs, 21 (38%) were grade I, 27 (49%) were grade II, and 7 (13%) were grade III. Increases were noted in DFROM over time, between 24 and 72 hours, at 2 to 4 weeks, and at 6 months (P < .05). The DFROM was less in participants with grade III than grade I LASs (P = .004) at 24 to 72 hours; INV length was greater at 24 to 72 hours than at 2 to 4 weeks (P = .023) and at 6 months (P = .035) than at 24 to 72 hours. The anterior drawer length (P = .001) and INV talofibular interval (P = .004) were greater in the LAS group than in the control group at 6 months.

CONCLUSIONS

Differences in range of motion and laxity were evident among grades at various time points and may indicate different clinical responses after an LAS.

Mobile Anatomical Total Ankle Arthroplasty-Improvement of Talus Recentralization

Introduction: Total ankle arthroplasty (TAA) is becoming a more frequent treatment option for end-stage ankle osteoarthritis (OA) as outcomes measures are improving. However, there is concern that malalignment of TAA can result in premature failure of the implant. One of the malalignment issues is the talar sagittal malposition. However, a consensus on the significance of the sagittal translation of the talus in TAA is yet to be established. The aim of this study was, therefore, to clarify whether talus OA subluxation is normalized after the implantation of a mobile TAA. Methods: Forty-nine consecutive patients with symptomatic end-stage ankle OA underwent 50 cementless three-component mobile-bearing VANTAGE TAA with 21 right ankles (42%) and 29 left ankles (58%). Clinical and radiographic outcomes were assessed: Clinical variables: American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score (0–100), visual analogue scale (VAS, 0–10), and ankle range of motion (ROM). Radiological variables: medial distal tibial articular angle (mDTAA), anterior distal tibial articular angle (aDTAA) and lateral talar station (LTS). Results: The clinical results showed the mean improvement in AOFAS hindfoot score from 42.12 ± SE 2.42 (Range: 9–72) preoperatively, to 96.02 ± SE 0.82 (Range: 78–100) at a mean follow-up of 12 months, with a highly statistically significant difference (p < 0.00001). Pain score (VAS) was 6.70 ± SE 0.28 (Range 0–10) preoperatively, and 0.26 ± SE 0.12 (Range: 0–3) at 12-month follow-up, with a highly statistically significant difference (p < 0.00001). ROM measurements preoperatively showed a mean of 22.55° ± SE 1.51° (Range: 0–50°), which showed a statistically significant improvement (p < 0.0001) to 45.43° ± SE 1.56° (Range: 25–60°) 12 months postoperatively. The radiological analyses revealed the following results: On the coronal view, the mDTAA preoperatively was 88.61 ± SE 0.70 (Range: 78.15–101.10), which improved to 89.46 ± SE 0.40 (Range: 81.95–95.80) at 12 months (not statistically significant—p = 0.94). On the sagittal view, the preoperative values of the aDTAA showed 82.66 ± SE 0.84 (Range: 70.35–107.47), which improved to 88.98 ± SE 0.47 (Range: 82.83–96.32) at 12 months postoperatively, with a highly statistically significant difference between preoperative and 12-months values (p < 0.00001). The mean LTS values for all patients were 3.95 mm ± SE 0.78 (Range: −11.52 to 13.89) preoperatively and 1.14 mm ± SE 0.63 (Range: −10.76 to 11.75) at 12 months, with a statistically significant difference between preoperative and 12-month follow-up (p = 0.01). The review of the radiological TAA osteointegration at 12 months showed no cases of loosening of the implanted TAAs. Two cases (4%) showed a radiolucency and one case (2%) a cyst on the tibial component; no cases had a change on the talar component. No TAA complication/revision surgeries were documented. Conclusion: In the present study, the lateral talar station of anteriorly subluxated ankles showed a significant improvement, i.e., physiological centralization of the talus, in the postoperative period when a mobile-bearing TAA was performed. The anterior/posterior congruency between the talar component and the mobile polyethylene insert of the mobile-bearing VANTAGE TAA allows the sagittal translation of the talus relative to the flat tibial component, reducing the prosthesis strain and failure.

The Effects of Therapeutic Exercise With and Without Mobilization in Participants With Chronic Ankle Instability: A Randomized Controlled Trial

Context: Manual therapy (MT) is reported to increase range of motion (ROM), improve balance, and decrease pain in individuals with chronic ankle instability (CAI). Additional literature is needed to examine the effectiveness of the addition of MT to a therapeutic exercise regimen in individuals with CAI. Objective: To examine the combined effects of thrust joint manipulation (TJM) and exercise on function in participants reporting CAI. Design: Randomized controlled trial. Setting: Research laboratory. Participants: A convenience sample of 30 participants (mean age 23.7 [3.65] y; mean height 169.50 [9.50] cm; mean mass 66.48 [10.64] kg). Intervention: Participants were randomly allocated to the exercise (n = 15) or exercise + TJM group (n = 20) and completed an exercise program. The exercise + TJM group also received MT at the talocrural, proximal, and distal tibiofibular joints in the first 3 sessions. Main Outcome Measures: Self-reported outcomes were recorded at baseline and follow-up using the Foot and Ankle Ability Measure (FAAM), the FAAM-Sport (FAAM-S) subscale, and the Ankle Joint Functional Assessment Tool (AJFAT). The side-hop test, figure-of-8 hop test, 3 directions of the Star Excursion Balance Test, and dorsiflexion ROM were also assessed at baseline and follow-up. Results: Only the exercise + TJM group demonstrated an improvement in weight-bearing dorsiflexion with the knee flexed following treatment (P = .02). For all outcome measures, except ROM, subjects improved significantly at follow-up regardless of group assignment (P ≤ .01). Conclusions: Our data suggest that rehabilitation of patients with CAI is related to improved ROM, function, and self-reported outcomes. This provides evidence that the addition of MT to exercise may enhance improvements in ROM as compared with exercise alone. Additional research is needed to identify optimal parameters to maximize therapeutic benefit.

The Examination of Repeated Self-Mobilizations With Movement and Joint Mobilizations on Individuals With Chronic Ankle Instability

CONTEXT

Chronic ankle instability (CAI) is one of the most common chronic conditions in the world, resulting in millions of dollars contributed to the health care system. Joint mobilizations have been shown to effectively improve patient and disease-specific impairments secondary to CAI. The ability for patients to complete an effective manual therapy intervention without the need for continuous visits to a health care provider can alleviate burdens on the health care system and improve patient satisfaction.

OBJECTIVE

To examine the effect of clinician-applied Maitland talocrural joint mobilization and self-mobilization (Self-Mob) on dorsiflexion range of motion (DFROM), dynamic balance, strength, and perceived function in those with CAI.

DESIGN

Single-blind randomized trial.

SETTING

Research laboratory.

PARTICIPANTS

A total of 18 participants (7 males and 11 females; age = 20.78 [2.02] y, height = 67.66 [3.83] cm, limb length = 87.74 [5.05] cm) with self-reported CAI participated.

INTERVENTIONS

The participants received 6 interventions over a 2-week period. The participants received either Maitland grade III anterior-to-posterior talocrural joint mobilizations or weight-bearing lunge Self-Mob. Each intervention consisted of four 2-minute sets, with a 1-minute rest between sets.

MAIN OUTCOME MEASURES

The DFROM (weight-bearing lunge), dynamic balance (Y-Balance Test), isometric strength, Foot and Ankle Ability Measure Quick, Disablement of the Physically Active modified, Fear Avoidance Beliefs Questionnaire, and Tampa Scale of Kinesiophobia-11 were measured preintervention and postintervention.

RESULTS

Dynamic balance, isometric strength, and perceived function significantly improved in both groups at postintervention. The DFROM significantly improved in the Self-Mob group. Higher individual responder rates were demonstrated within the Self-Mob group compared with clinician-applied mobilizations.

CONCLUSIONS

Clinician-applied mobilizations and Self-Mobs are effective interventions for improving dynamic balance, isometric strength, and perceived function. Application of Self-Mobs can effectively improve DFROM compared with joint mobilization. Self-Mobs may be an effective intervention to incorporate into a home care plan.

In vivo kinematics of functional ankle instability patients during the stance phase of walking

BACKGROUND

Previous studies showed functional ankle instability (FAI) patients have morphological ligamentous abnormality, despite having no apparent joint laxity.

RESEARCH QUESTION

Whether tibiotalar and subtalar joints hypermobility exists in FAI patients during stance phase of walking, remains controversial.

METHODS

Ten unilateral FAI patients, ten unilateral lateral ankle sprain (LAS) copers and ten healthy controls were included. A dual fluoroscopy imaging system was utilized to capture the fluoroscopic images of tibiotalar and subtalar joint during the stance phase of walking. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint excursions about six degrees of freedom were compared among the three groups. The correlations between range of motion and Cumberland Ankle Instability Tool (CAIT) scores were assessed utilizing the Spearman's correlation coefficient (r).

RESULTS

During the stance phase, the FAI patients and LAS copers showed larger tibiotalar anterior/posterior translation than the healthy controls (FAI patients, p = .013; LAS copers, p = .002). The FAI patients also showed significantly larger lateral/medial translation (p = .035) and inversion/eversion rotation (p = .003) of subtalar joints than healthy controls. By contrast, the subtalar joints of the LAS copers were not different from those of the healthy controls in the lateral/medial translation (p = .459) and inversion/eversion rotation (p = .091). CAIT scores were negatively correlated with range of motion.

SIGNIFICANCE

During the stance phase of walking, FAI patients showed significantly larger hypermobility of subtalar joints than healthy controls, contrary to the LAS copers. These findings justify the utilization of dual fluoroscopy imaging system to detect joint hypermobility in FAI patients. Treatment for FAI patients may require stabilization of the subtalar joint.

Plausible mechanisms of and techniques to assess ankle joint degeneration following lateral ankle sprains: a narrative review

Lateral ankle sprain (LAS) is the most common lower extremity musculoskeletal injury sustained during daily life and sport. The cascade of events that starts with ligamentous trauma leads to clinical manifestations such as recurrent sprains and giving way episodes, hallmark characteristics of chronic ankle instability (CAI). The sequelae of lateral ankle sprains and CAI appear to contribute to aberrant biomechanics. Combined, joint trauma and aberrant biomechanics appear to directly and/or indirectly play a role in talar cartilage degeneration. Up to 80% of all cases of ankle osteoarthritis (OA) are post-traumatic in nature and common etiologies for ankle post-traumatic osteoarthritis (PTOA) are histories of a single and recurrent ankle sprains. Despite known links between LAS, CAI, and PTOA and evidence demonstrating the burden of LAS and its sequelae, early pathoetiological changes of ankle PTOA and how they can be assessed are poorly understood. Therefore, the purpose of this paper is to review the plausible mechanistic links among LAS and its sequelae of CAI and PTOA as well as review non-surgical techniques that can quantify talar cartilage health. Understanding the pathway from ligamentous ankle injury to ankle PTOA is vital to developing theoretically sound therapeutic interventions aimed at slowing ankle PTOA progression. Further, directly assessing talar cartilage health non-surgically provides opportunities to quantify if current and novel intervention strategies are able to slow the progression of ankle PTOA.

The Ankle-Joint Complex: A Kinesiologic Approach to Lateral Ankle Sprains

Copious research exists regarding ankle instability, yet lateral ankle sprains (LASs) persist in being among the most common recurrent musculoskeletal injuries. Key anatomical structures of the ankle include a triform articulating structure that includes the inferior tibiofibular, talocrural, and subtalar joints. Functionally, force absorption and propulsion through the ankle complex are necessary for any task that occurs in weight bearing. For optimal ankle performance and avoidance of injury, an intricate balance between stability and mobility is necessary to ensure that appropriate force transfer occurs during sports and activities of daily living. Consideration for the many structures that may be directly or indirectly involved in LASs will likely translate into advancements in clinical care. In this clinical review, we present the structure, function, and relevant pathologic states of the ankle complex to stimulate a better understanding of the prevention, evaluation, and treatment of LASs.

Evaluating and Differentiating Ankle Instability

Given the prevalence of lateral ankle sprains during physical activity and the high rate of reinjury and chronic ankle instability, clinicians should be cognizant of the need to expand the evaluation of ankle instability beyond the acute time point. Physical assessments of the injured ankle should be similar, regardless of whether this is the initial lateral ankle sprain or the patient has experienced multiple sprains. To this point, a thorough injury history of the affected ankle provides important information during the clinical examination. The physical examination should assess the talocrural and subtalar joints, and clinicians should be aware of efficacious diagnostic tools that provide information about the status of injured structures. As patients progress into the subacute and return-to-activity phases after injury, comprehensive assessments of lateral ankle-complex instability will identify any disease and patient-oriented outcome deficits that resemble chronic ankle instability, which should be addressed with appropriate interventions to minimize the risk of developing long-term, recurrent ankle instability.

An Updated Model of Chronic Ankle Instability

Lateral ankle sprains (LASs) are among the most common injuries incurred during participation in sport and physical activity, and it is estimated that up to 40% of individuals who experience a first-time LAS will develop chronic ankle instability (CAI). Chronic ankle instability is characterized by a patient's being more than 12 months removed from the initial LAS and exhibiting a propensity for recurrent ankle sprains, frequent episodes or perceptions of the ankle giving way, and persistent symptoms such as pain, swelling, limited motion, weakness, and diminished self-reported function. We present an updated model of CAI that aims to synthesize the current understanding of its causes and serves as a framework for the clinical assessment and rehabilitation of patients with LASs or CAI. Our goal was to describe how primary injury to the lateral ankle ligaments from an acute LAS may lead to a collection of interrelated pathomechanical, sensory-perceptual, and motor-behavioral impairments that influence a patient's clinical outcome. With an underpinning of the biopsychosocial model, the concepts of self-organization and perception-action cycles derived from dynamic systems theory and a patient-specific neurosignature, stemming from the Melzack neuromatrix of pain theory, are used to describe these interrelationships.

Altered Walking Neuromechanics in Patients With Chronic Ankle Instability

CONTEXT

The literature on gait kinematics and muscle activation in chronic ankle instability (CAI) is limited. A comprehensive evaluation of all relevant gait measures is needed to examine alterations in gait neuromechanics that may contribute to recurrent sprain.

OBJECTIVE

To compare walking neuromechanics, including kinematics, muscle activity, and kinetics (ie, ground reaction force [GRF], moment, and power), between participants with and those without CAI by applying a novel statistical analysis to data from a large sample.

DESIGN

Controlled laboratory study.

SETTING

Biomechanics laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 100 participants with CAI (49 men, 51 women; age = 22.2 ± 2.3 years, height = 174.0 ± 9.7 cm, mass = 70.8 ± 14.4 kg) and 100 individuals without CAI serving as controls (55 men, 45 women; age = 22.5 ± 3.3 years, height = 173.1 ± 13.3 cm, mass = 72.6 ± 18.7 kg).

INTERVENTION(S)

Participants performed 5 trials of walking (shod) at a self-selected speed over 2 in-ground force plates.

MAIN OUTCOME MEASURE(S)

Three-dimensional GRFs, lower extremity joint angles, internal joint moments, joint powers, and activation amplitudes of 6 muscles were recorded during stance.

RESULTS

Compared with the control group, the CAI group demonstrated (1) increased plantar flexion or decreased dorsiflexion, increased inversion or decreased eversion, decreased knee flexion, decreased knee abduction, and increased hip-flexion angles; (2) increased or decreased inversion, increased plantar flexion, decreased knee extension, decreased knee abduction, and increased hip-extension moments; (3) increased vertical, braking, and propulsive GRFs; (4) increased hip eccentric and concentric power; and (5) altered muscle activation in all 6 lower extremity muscles.

CONCLUSIONS

The CAI group demonstrated a hip-dominant strategy by limiting propulsive forces at the ankle while increasing force generation at the hip. The different walking neuromechanics exhibited by the CAI group could represent maladaptive strategies that developed after the initial sprain or an injurious gait pattern that may have predisposed the participants to their initial injuries. Increased joint loading and altered kinematics at the foot and ankle complex during initial stance could affect the long-term health of the ankle articular cartilage.

The effectiveness of rearfoot medial wedge intervention on balance for athletes with chronic ankle instability

BACKGROUND

Athletes with chronic ankle instability (CAI) often develop complications such as pain, instability, and reduced postural control and balance stability, all of which affect athletic performance. This study investigated the effects of a 4° medal wedge intervention on static and dynamic balance in athletes with CAI.

METHODS

The participants were 24 healthy and 25 CAI athletes. Participants received a 4° medial wedge applied at the rear foot insole and completed the experiment measurements before and after the wedge intervention. The main outcome measures included the area and path length of the center of pressure when participants performed single-leg standing balance in the closed eye condition and the dynamic balance scores of a multiple single-leg hop stabilization test.

RESULTS

The single-leg standing balance significantly improved in CAI (P = .027) and control groups (P = .005) after the medial wedge intervention. The dynamic balance scores significantly decreased from 53.00 ± 25.22 to 41.24 ± 21 48 (P = .015) in CAI group after medial wedge intervention.

CONCLUSION

Wearing a 4° medial wedge applied at the rear foot insole improved static and dynamic balance immediately in athletes with CAI. We suggest that clinicians may provide the foot insole to improve balance deficit in athletes having CAI.

Acute effects of distal fibular taping technique on pain, balance and forward lunge activities in Chronic Ankle Instability

BACKGROUND

Chronic Ankle Instability (CAI) is characterized by altered muscle activation, reduced range of motion (ROM) and balance deficits.

OBJECTIVE

The aim of this study was to determine whether fibular taping technique influenced the pain intensity, dorsiflexion ROM and dynamic balance in participants with CAI.

METHODS

Twenty-six participants (16 males and 10 females; age 28.8 ± 5.74 y) with unilateral CAI who scored 85 points or less on the Foot and Ankle Outcome Score (FAOS) were included in our study. Mulligan distal fibular taping technique was applied. Visual Analog Scale, Star Excursion Balance Test in anterior, posteromedial and posterolateral directions and a Weight Bearing Lunge Test were taken before, after, 1 hour after and 24 hours after taping.

RESULTS

Distal fibular taping technique decreases pain intensity (at rest, during range of motion and weight bearing conditions), while it increases forward lunge distance and reach distance in anterior, posteromedial and posterolateral directions (p= 0.001).

CONCLUSIONS

Our study showed that distal fibular taping reduces pain intensity, postural control and dorsiflexion range of motion in individuals with CAI. Further studies are needed with participants with a lower functional level and a higher pain intensity.

Changes in Dorsiflexion and Dynamic Postural Control After Mobilizations in Individuals With Chronic Ankle Instability: A Systematic Review and Meta-Analysis

OBJECTIVE

To conduct a systematic review with meta-analysis assessing the effectiveness of joint mobilizations for improving dorsiflexion range of motion (DFROM) and dynamic postural control in individuals with chronic ankle instability.

DATA SOURCES

Electronic databases (PubMed, MEDLINE, CINAHL, and SPORTDiscus) were searched from inception to January 2017.

STUDY SELECTION

Included studies examined the isolated effects of joint mobilizations to enhance DFROM and dynamic postural control in individuals with chronic ankle instability and provided adequate data to calculate effect sizes (ESs) and 95% confidence intervals (CIs).

DATA EXTRACTION

Two investigators independently assessed the methodologic quality, level of evidence, and strength of recommendation using the Physiotherapy Evidence Database scale and the Strength of Recommendation Taxonomy. We extracted the sample sizes, means, and standard deviations for DFROM and dynamic postural control and filtered the data based on control-to-intervention and preintervention-to-postintervention (pre-post) comparisons.

DATA SYNTHESIS

We included 7 level 1 and 3 level 2 studies that had a median Physiotherapy Evidence Database score of 60% (range = 40%-80%). The magnitudes of control-to-intervention and pre-post differences were examined using bias-corrected Hedges g ESs. Random-effects meta-analyses were conducted for each outcome measure and comparison. Positive ESs indicated better outcome scores in the intervention group than in the control group and at postintervention than at preintervention. The α level was set at .05. Meta-analysis revealed weak and moderate ESs for overall control-to-intervention (ES = 0.41; 95% CI = 0.14, 0.68; P = .003) and pre-post (ES = 0.34; 95% CI = 0.20, 0.48; P < .001) DFROM analyses. Overall, dynamic postural control meta-analysis revealed moderate control-to-intervention (ES = 0.42; 95% CI = -0.14, 0.98; P = .14) and weak and moderate ESs for pre-post (ES = 0.37; 95% CI = -0.12, 0.87; P = .14) analyses.

CONCLUSIONS

We observed grade A evidence that joint mobilizations can mildly improve DFROM among individuals with chronic ankle instability compared with controls and preintervention. We observed grade B evidence that indicated conflicting effects of joint mobilizations on dynamic postural control compared with controls and preintervention.

Clinical assessment of acute lateral ankle sprain injuries (ROAST): 2019 consensus statement and recommendations of the International Ankle Consortium

Lateral ankle sprain injury is the most common musculoskeletal injury incurred by individuals who participate in sports and recreational physical activities. Following initial injury, a high proportion of individuals develop long-term injury-associated symptoms and chronic ankle instability. The development of chronic ankle instability is consequent on the interaction of mechanical and sensorimotor insufficiencies/impairments that manifest following acute lateral ankle sprain injury. To reduce the propensity for developing chronic ankle instability, clinical assessments should evaluate whether patients in the acute phase following lateral ankle sprain injury exhibit any mechanical and/or sensorimotor impairments. This modified Delphi study was undertaken under the auspices of the executive committee of the International Ankle Consortium. The primary aim was to develop recommendations, based on expert (n=14) consensus, for structured clinical assessment of acute lateral ankle sprain injuries. After two modified Delphi rounds, consensus was achieved on the clinical assessment of acute lateral ankle sprain injuries. Consensus was reached on a minimum standard clinical diagnostic assessment. Key components of this clinical diagnostic assessment include: establishing the mechanism of injury, as well as the assessment of ankle joint bones and ligaments. Through consensus, the expert panel also developed the International Ankle Consortium Rehabilitation-Oriented ASsessmenT (ROAST). The International Ankle Consortium ROAST will help clinicians identify mechanical and/or sensorimotor impairments that are associated with chronic ankle instability. This consensus statement from the International Ankle Consortium aims to be a key resource for clinicians who regularly assess individuals with acute lateral ankle sprain injuries.

Assessment of Relationships Between Joint Motion Quality and Postural Control in Patients With Chronic Ankle Joint Instability

Study Design Controlled laboratory study, cross-sectional. Background Lateral ankle sprains are among the most common injuries encountered during athletic participation. Following the initial injury, there is an alarmingly high risk of reinjury and development of chronic ankle instability (CAI), which is dependent on a combination of factors, including sensorimotor deficits and changes in the biomechanical environment of the ankle joint. Objective To evaluate CAI-related disturbances in arthrokinematic motion quality and postural control and the relationships between them. Methods Sixty-three male subjects (31 with CAI and 32 healthy controls) were enrolled in the study. For arthrokinematic motion quality analysis, the vibroarthrographic signals were collected during ankle flexion/extension motion using an acceleration sensor and described by variability (variance of mean squares [VMS]), amplitude (mean of 4 maximal and 4 minimal values [R4]), and frequency (vibroarthrographic signal bands of 50 to 250 Hz [P1] and 250 to 450 Hz [P2]) parameters. Using the Biodex Balance System, single-leg dynamic balance was measured by overall, anteroposterior, and mediolateral stability indices. Results Values of vibroarthrographic parameters (VMS, R4, P1 and P2) were significantly higher in the CAI group than those in the control group (P<.01). Similar results were obtained for all postural control parameters (overall, anteroposterior, and mediolateral stability indices; P<.05). Moreover, correlations between the overall stability index and VMS, and P1 and P2, as well as between the anteroposterior stability index and P1 and P2, were observed in the CAI patient group, but not in controls. Conclusion In patients with CAI, deficits in both quality of ankle arthrokinematic motion and postural control were present. Therefore, physical therapy interventions focused on improving ankle neuromuscular control and arthrokinematic function are necessary in CAI patient care. J Orthop Sports Phys Ther 2017;47(8):570-577. Epub 4 Nov 2016. doi:10.2519/jospt.2017.6836.

Novel treatment of lateral ankle sprains using the Mulligan concept: an exploratory case series analysis

Objective

The purpose of this study was to examine the effect of the Mulligan Concept (MC) Mobilization with movement (MWM) in the treatment of clinically diagnosed acute lateral ankle sprains in competitive athletes.

Methods

A prospective case series of 5 adolescent patients, ages ranging from 14 to 18 years (mean = 15.8 ± 1.64), that suffered an acute lateral ankle sprain (LAS). Patients were treated with the MC lateral ankle MWM. Mobilization was directed at the distal fibula or, using a modified MWM, 2-3 inches proximal to the distal fibula. Using paired t-tests and descriptive statistics (mean and standard deviation) results were analyzed.

Results

Treatment lasted an average of 9 days (mean = 9.2, ±SD 3.96) from intake to discharge. During that time frame, patients reported decreases in pain on the numeric pain rating scale (NRS), disability on the Disablement in the Physically Active (DPA) scale and an increase in function on the patient-specific functional scale (PSFS); and an immediate decrease in pain on the NRS within the first treatment. The minimal detectable change for the PSFS and NRS were exceeded from intake to discharge. Additionally, the minimally clinical important differences were exceeded on the NRS and DPA scale.

Discussion

The evidence presented in this Level-4 case series supports the use of the MC lateral ankle MWM to treat patients diagnosed with acute grade II LAS. Patients in this case series reported immediate decreases in pain and immediate increases in function. Therefore, further investigation of the MC lateral ankle MWM is warranted.

Gait abnormalities in patients with chronic ankle instability can improve following a non-invasive biomechanical therapy: a retrospective analysis

[Purpose] The purpose of this study was to evaluate the changes in gait patterns and clinical outcomes of patients with chronic ankle instability (CAI) following treatment with a home-based non-invasive biomechanical device. [Subjects and Methods] Thirty-three patients with CAI were compared with 43 healthy controls. Patients underwent a spatiotemporal gait assessment before and three months following treatment. Clinical evaluation was recorded with SF-36 Health Survey and the Foot and Ankle Outcome Score (FAOS). [Results] Significant baseline differences were found between groups. Patients with CAI showed a statistically significant improvement in velocity, cadence, symptomatic limb step length and single limb support over time. Significant improvements in SF-36 PCS and FAOS outcome scores were found in patients with CAI. [Conclusion] Patients with CAI have baseline spatiotemporal gait abnormalities as compared with healthy controls. However, clinical and gait metrics improvement can be expected after 12 weeks of perturbation training using a non-invasive biomechanical device.

Sensory-Targeted Ankle Rehabilitation Strategies for Chronic Ankle Instability

INTRODUCTION

Deficient sensory input from damaged ankle ligament receptors is thought to contribute to sensorimotor deficits in those with chronic ankle instability (CAI). Targeting other viable sensory receptors may then enhance sensorimotor control in these patients. The purpose of this randomized controlled trial was to evaluate the effects of 2 wk of sensory-targeted ankle rehabilitation strategies (STARS) on patient- and clinician-oriented outcomes in those with CAI.

METHODS

Eighty patients with self-reported CAI participated. All patients completed patient-oriented questionnaires capturing self-reported function as well as the weight-bearing lunge test and an eyes-closed single-limb balance test. After baseline testing, patients were randomly allocated to four STARS groups: joint mobilization, plantar massage, triceps surae stretching, or control. Each patient in the intervention groups received six 5-min treatments of their respective STARS over 2 wk. All subjects were reassessed on patient- and clinician-oriented measures immediately after the intervention and completed a 1-month follow-up that consisted of patient-oriented measures. Change scores of the three STARS groups were compared with the control using independent t-tests and Hedges' g effect sizes with 95% confidence intervals.

RESULTS

The joint mobilization group had the greatest weight-bearing lunge test improvement. Plantar massage had the most meaningful single-limb balance improvement. All STARS groups improved patient-oriented outcomes with joint mobilization having the most meaningful effect immediately after the intervention and plantar massage at the 1-month follow-up.

CONCLUSION

Each STARS treatment offers unique contributions to the patient- and clinician-oriented rehabilitation outcomes of those with CAI. Both joint mobilization and plantar massage appear to demonstrate the greatest potential to improve sensorimotor function in those with CAI.

Therapeutic interventions for improving self-reported function in patients with chronic ankle instability: a systematic review

OBJECTIVE

To identify which therapeutic intervention may be most effective for improving self-reported function in patients with chronic ankle instability (CAI).

DESIGN

Systematic literature review. Articles were appraised using the Downs and Black Checklist by 3 reviewers.

DATA SOURCES

PubMed along with CINAHL, MEDLINE and SPORTDiscus within EBSCOhost for pertinent articles from their inception through August 2016.

ELIGIBILITY CRITERIA FOR SELECTED STUDIES

Articles included were required to (1) be written in English, (2) report adequate data to calculate effect sizes, (3) identify patients with CAI, (4) use some form of therapeutic intervention and (5) use a self-reported questionnaire as a main outcome measurement.

RESULTS

A broad spectrum of therapeutic interventions were identified related to balance training, multimodal rehabilitation, joint mobilisation, resistive training, soft-tissue mobilisation, passive calf stretching and orthotics. All of the articles included in the balance training category had moderate-to-strong Hedges g with none of the 95% CIs crossing 0. Hedges g effect sizes ranged from -0.67 to -2.31 and -0.51 to -1.43 for activities of daily living and physical activity, respectively. The multimodal rehabilitation category also produced moderate-to-strong Hedges g effect sizes but with large CIs crossing 0. Hedges g effect sizes ranged from -0.47 to -9.29 and -0.62 to -24.29 for activities of daily living and physical activity, respectively.

CONCLUSIONS

The main findings from this systematic review were balance training provided the most consistent improvements in self-reported function for patients with CAI.

Sagittal Distal Tibial Articular Angle and the Relationship to Talar Subluxation in Total Ankle Arthroplasty

BACKGROUND

Longevity of total ankle replacement (TAR) depends heavily on anatomic alignment. The lateral talar station (LTS) classifies the sagittal position of the talus relative to the tibia. We hypothesized that correcting the sagittal distal tibial articular angle (sDTAA) during TAR would anatomically realign the tibiotalar joint and potentially reduce the risk of prosthesis subluxation.

METHODS

The LTS (millimeters) and sDTAA (degrees) were measured twice by 2 blinded observers using weight-bearing lateral ankle radiographs obtained before (n = 96) and after (n = 94) TAR, with excellent interobserver and intraobserver reliability (correlation coefficient >0.9).

RESULTS

Preoperative LTS was as follows: anterior (60.4%), posterior (27.1%), and neutral (12.5%). A strong preoperative correlation was found between LTS and sDTAA (r = 0.81; P < .0001). In ankles that were initially anterior and became less anterior postoperatively (n = 41), LTS decreased from an average 8.1 mm to 6.5 mm and the LTS changed 1.1 mm per degree of sDTAA change. In ankles that were initially posterior (n = 25), LTS increased from an average of -5.1 mm to -2.8 mm and the LTS changed 0.6 mm per degree of sDTAA change. The correlation between LTS and sDTAA was reduced postoperatively (r = 0.62; P < .0001).

CONCLUSIONS

Our results suggest that rather than following generic recommendations, the surgeon should customize the sagittal distal tibial cut to the individual patient based on the preoperative LTS in order to achieve neutral TAR alignment.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Relationships between mechanical joint stability and somatosensory function in individuals with chronic ankle instability

BACKGROUND

Individuals with chronic ankle instability (CAI) have demonstrated alterations in ankle mechanics and deficits in sensory function. However, relationships between mechanical stability and somatosensory function have not been examined, nor have those between somatosensory function and injury history characteristics. Therefore, the objective of this study was to examine relationships between (1) somatosensory function and mechanical stability and (2) somatosensory function and injury history characteristics.

METHODS

Forty adults with CAI volunteered to participate. In a single testing session, participants completed mechanical and sensory assessments in a counterbalanced order. Dependent variables included anterior/posterior displacement (mm), inversion/eversion rotation (°), SWM index values, JPS absolute error (°), number of previous ankle sprains, and number of "giving way" episodes in the previous 3 months. Spearman's Rho correlations examined the relationships between somatosensory function and (1) mechanical stability and (2) injury history characteristics (p<0.05).

RESULTS

No significant correlations were identified between any variables (p>0.11), and all r-values were considered weak.

CONCLUSIONS

These results revealed somatosensory function was not significantly correlated to mechanical stability or injury history characteristics. This indicates peripheral sensory impairments associated with CAI are likely caused by factors other than mechanical stability and injury history characteristics.

Posterolateral ankle ligament injuries affect ankle stability: a finite element study

BACKGROUND

We have already discovered 23 patients during the work of the outpatient department and operations whose unstable signs on the posterolateral ankle. The anterior drawer test demonstrated normal during the physical examinations while the spaces of the posterior tibiotalar joints increased in stress X-ray plain films. ATFL intact and posterolateral ligaments lax were found during operations too. It is important to make existence claims and illuminate the mechanism of posterolateral ankle instability.

METHODS

A finite element model of the ankle was established for simulating to cut off posterolateral ligaments in turn. Ankle movements with tibia rotation under load on five forefoot positions were simulated as well.

RESULTS

The difference values with tibia external rotation were negative, and the positive results occurred with tibia internal rotation. The tibia-talus difference values in some forefoot positions were 2 ~ 3 mm after PTFL together with CFL or/and PITFL were cut off. The tibula-talus difference values were 2.21 ~ 2.76 mm after both PTFL and CFL were cut off. The tibia-fibula difference values were small. The difference values increased by 2 ~ 5 mm after cutting off the PITFL.

CONCLUSIONS

Posterolateral ankle ligaments, especially CFL and PITFL, play a significant role in maintaining ankle stability. The serious injuries of both CFL and PITFL would affect posterolateral ankle stabilities. PITFL was important to subtalar joint stability.

Weight-Bearing Dorsiflexion Range of Motion and Landing Biomechanics in Individuals With Chronic Ankle Instability

CONTEXT

People with chronic ankle instability (CAI) exhibit less weight-bearing dorsiflexion range of motion (ROM) and less knee flexion during landing than people with stable ankles. Examining the relationship between dorsiflexion ROM and landing biomechanics may identify a modifiable factor associated with altered kinematics and kinetics during landing tasks.

OBJECTIVE

To examine the relationship between weight-bearing dorsiflexion ROM and single-legged landing biomechanics in persons with CAI.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

Fifteen physically active persons with CAI (5 men, 10 women; age = 21.9 ± 2.1 years, height = 168.7 ± 9.0 cm, mass = 69.4 ± 13.3 kg) participated.

INTERVENTION(S)

Participants performed dorsiflexion ROM and single-legged landings from a 40-cm height. Sagittal-plane kinematics of the lower extremity and ground reaction forces (GRFs) were captured during landing.

MAIN OUTCOME MEASURE(S)

Static dorsiflexion was measured using the weight-bearing-lunge test. Kinematics of the ankle, knee, and hip were observed at initial contact, maximum angle, and sagittal displacement. Sagittal displacements of the ankle, knee, and hip were summed to examine overall sagittal displacement. Kinetic variables were maximum posterior and vertical GRFs normalized to body weight. We used Pearson product moment correlations to evaluate the relationships between dorsiflexion ROM and landing biomechanics. Correlations (r) were interpreted as weak (0.00-0.40), moderate (0.41-0.69), or strong (0.70-1.00). The coefficient of determination (r(2)) was used to determine the amount of explained variance among variables.

RESULTS

Static dorsiflexion ROM was moderately correlated with maximum dorsiflexion (r = 0.49, r(2) = 0.24), ankle displacement (r = 0.47, r(2) = 0.22), and total displacement (r = 0.67, r(2) = 0.45) during landing. Dorsiflexion ROM measured statically and during landing demonstrated moderate to strong correlations with maximum knee (r = 0.69-0.74, r(2) = 0.47-0.55) and hip (r = 0.50-0.64, r(2) = 0.25-0.40) flexion, hip (r = 0.53-0.55, r(2) = 0.28-0.30) and knee (r = 0.53-0.70, r(2) = 0.28-0.49) displacement, and vertical GRF (-0.47- -0.50, r(2) = 0.22-0.25).

CONCLUSIONS

Dorsiflexion ROM was moderately to strongly related to sagittal-plane kinematics and maximum vertical GRF during single-legged landing in persons with CAI. Persons with less dorsiflexion ROM demonstrated a more erect landing posture and greater GRF.

Lateral Ankle Sprain and Chronic Ankle Instability: A Critical Review

Many studies investigated the contributing factors of chronic ankle instability, but a consensus has not yet been obtained. The objective of this critical review is to provide recent scientific evidence on chronic ankle instability, including the epidemiology and pathology of lateral ankle sprain as well as the causative factors of chronic ankle instability. We searched MEDLINE from 1964 to December 2013 using the terms ankle, sprain, ligament, injury, chronic, functional, mechanical, and instability. Lateral ankle sprain shows a very high recurrence rate and causes considerable economic loss due to medical care, prevention, and secondary disability. During the acute phase, patients with ankle sprain demonstrate symptoms such as pain, range of motion deficit, postural control deficit, and muscle weakness, and these symptoms may persist, leading to chronic ankle instability. Although some agreement regarding the effects of chronic ankle instability with deficits in postural control and/or concentric eversion strength exists, the cause of chronic ankle instability remains controversial.

LEVELS OF EVIDENCE

Therapeutic Level IV: Review of Level IV studies.

Active ankle motion may result in changes to the talofibular interval in individuals with chronic ankle instability and ankle sprain copers: a preliminary study

INTRODUCTION

Alterations in talocrural joint arthrokinematics related to repositioning of the talus or fibula following ankle sprain have been reported in radiological and clinical studies. It is unclear if these changes can result from normal active ankle motion. The study objective was to determine if active movement created changes in the sagittal plane talofibular interval in ankles with a history of lateral ankle sprain and instability.

METHODS

Three subject groups [control (n = 17), ankle sprain copers (n = 20), and chronic ankle instability (n = 20)] underwent ultrasound imaging of the anterolateral ankle gutter to identify the lateral malleolus and talus over three trials. Between trials, subjects actively plantar and dorsiflexed the ankle three times. The sagittal plane talofibular interval was assessed by measuring the anteroposterior distance (mm) between the lateral malleolus and talus from an ultrasound image. Between group and trial differences were analyzed with repeated measures analysis of variance and post-hoc t-tests.

RESULTS

Fifty-seven subjects participated. A significant group-by-trial interaction was observed (F4,108 = 3.5; P = 0.009). The talofibular interval was increased in both copers [2.4±3.6 mm; 95% confidence interval (CI): 0.73-4.1; P = 0.007] and chronic ankle instability (4.1±4.6 mm; 95% CI: 1.9-6.2; P = 0.001) at trial 3 while no changes were observed in control ankle talar position (0.06±2.8mm; 95% CI: -1.5-1.4; P = 0.93).

DISCUSSION

The talofibular interval increased only in subjects with a history of lateral ankle sprain with large clinical effect sizes observed. These findings suggest that an alteration in the position of the talus or fibula occurred with non-weight bearing sagittal plane motion. These findings may have diagnostic and therapeutic implications for manual therapists.

Plantarflexor and Dorsiflexor Activation during Inclined Walking with and without Modified Mobilization with Movement Using Tape in Women with Limited Ankle Dorsiflexion

[Purpose] This study compared the EMG activities of the plantarflexor and dorsiflexor muscles during inclined walking with and without modified mobilization with movement (modified MWM) using tape in women with limited ankle dorsiflexion. [Subjects] Fifteen women with limited dorsiflexion in their feet (22 feet in total) were recruited for this study. [Methods] The subjects walked with and without modified MWM using tape on a treadmill at 6 degrees with a speed of 1.25 m/s for 5 minutes. The EMG activities of the medial gastrocnemius (GCM) and tibialis anterior (TA) muscles were measured using a surface EMG system. [Results] During incline walking with modified MWM using tape, the mean EMG activity of the GCM significantly increased, and that of the TA decreased between heel strike and heel off. There was no difference between heel off and toe off in the two muscles. [Conclusions] Modified MWM using tape on the talus during incline walking could alter the muscle activities of the GCM and TA between heel strike and heel off in women with limited ankle dorsiflexion.

Joint mobilization acutely improves landing kinematics in chronic ankle instability

PURPOSE

The objective of this study is to examine the acute effect of ankle joint mobilizations akin to those performed in everyday clinical practice on sagittal plane ankle joint kinematics during a single-leg drop landing in participants with chronic ankle instability (CAI).

METHODS

Fifteen participants with self-reported CAI (defined as <24 on the Cumberland Ankle Instability Tool) performed three single-leg drop landings under two different conditions: 1) premobilization and, 2) immediately, postmobilization. The mobilizations performed included Mulligan talocrural joint dorsiflexion mobilization with movement, Mulligan inferior tibiofibular joint mobilization, and Maitland anteroposterior talocrural joint mobilization. Three CODA cx1 units (Charnwood Dynamics Ltd., Leicestershire, UK) were used to provide information on ankle joint sagittal plane angular displacement. The dependent variable under investigation was the angle of ankle joint plantarflexion at the point of initial contact during the drop landing.

RESULTS

There was a statistically significant acute decrease in the angle of ankle joint plantarflexion from premobilization (34.89° ± 4.18°) to postmobilization (31.90° ± 5.89°), t(14) = 2.62, P < 0.05 (two-tailed). The mean decrease in the angle of ankle joint plantarflexion as a result of the ankle joint mobilization was 2.98° with a 95% confidence interval ranging from 0.54 to 5.43. The eta squared statistic (0.32) indicated a large effect size.

CONCLUSION

These results indicate that mobilization acted to acutely reduce the angle of ankle joint plantarflexion at initial contact during a single-leg drop landing. Mobilization applied to participants with CAI has a mechanical effect on the ankle joint, thus facilitating a more favorable positioning of the ankle joint when landing from a jump.

Reliability and validity of a weight-bearing measure of ankle dorsiflexion range of motion

PURPOSE

To examine reliability and validity of the Lunge Test (LT) of dorsiflexion range of motion and determine the impact of different approaches to obtain a score on these parameters.

METHODS

Fifty-three patients with ankle injury/dysfunction provided initial assessment data for cross-sectional convergent and known-groups validity analysis with the Pearson coefficient (r) and paired t-test, respectively; data after 4-8 weeks of treatment for longitudinal validity analysis with coefficient r; and data 3 days later for test-retest reliability using the intra-class correlation coefficient (ICC) and minimal detectable change (MDC). LT scores were determined for the affected leg only (LTAff) and for the difference between the two limbs (LTDiff). Two strategies were used to calculate LT scores: a single series and the mean of three series of lunges. LTs were correlated with the Lower Extremity Functional Scale and Global Foot and Ankle Scale.

RESULTS

Reliability coefficients were high (ICC=0.93-0.99). The MDC=1.0/1.5 cm, LTAff/LTDiff, respectively. Cross-sectional validity was confirmed for LTDiff (r=-0.40 to -0.50). Between-limb differences (p<0.05) supported known-groups validity. Longitudinal validity was supported for both LT change scores (r=0.39-0.63). The number of series of lunges used did not impact results.

CONCLUSIONS

A single series of lunges produces a reliable LT score. From a validity perspective, clinicians should use LTDiff on initial assessment and either LT to assess change.

Fibular taping does not influence ankle dorsiflexion range of motion or balance measures in individuals with chronic ankle instability

OBJECTIVES

To determine the effects of fibular taping on ankle dorsiflexion range of motion (ROM) and dynamic balance in individuals with chronic ankle instability (CAI).

DESIGN

Single-blind, randomized crossover.

METHODS

Twenty-three individuals (age=23.4 ± 2.5 years, height=171.6 ± 12.4 cm, mass=71.5±13.1 kg) with CAI were allocated to either a fibular taping intervention or sham taping intervention (tape applied without tension) over the course of two visits. Weight-bearing ankle dorsiflexion ROM and components of the Star Excursion Balance Test (SEBT) were measured before and after intervention.

RESULTS

There was not a significant change in ankle dorsiflexion ROM when comparing the taping interventions (F1,43=1.03, P=.32), but both interventions resulted in a small increase (F1,43=8.07, P=.007) in dorsiflexion ROM (pre=36.7° ± 6.9°, post=37.7° ± 6.2°). This increase in ROM did not exceed the established minimal detectable change for dorsiflexion ROM. Fibular taping with tension produced an increase (F1,41=5.84, P=.02) (pre=69.0 ± 9.1%, post=70.6±8.6%) in posterolateral reach distance when compared to taping without tension (pre=72.7 ± 11.0%, post=71.4 ± 9.6%), but this increase did not exceed the established minimal detectable change. There was not a significant change in dynamic balance between groups for the anterior (F1,41=2.33, P=.14) and posteromedial (F1,41=.41, P=.53) reach directions.

CONCLUSIONS

Although small changes in ankle dorsiflexion ROM and posterolateral reach distances were observed, these changes did not exceed established minimal detectable change values for these measures. These results suggest that the benefits of fibular taping are not related to an increase in ankle dorsiflexion ROM or dynamic balance.