Knee and ankle position, anterior drawer laxity, and stiffness of the ankle complex

Assessing Lateral Ankle Sprains With a New Arthrometer

BACKGROUND

Lateral ankle sprains are a common musculoskeletal injury across a variety of activities. Researchers have sought to identify a method to objectively assess joint laxity with a device that is simple to use and affordable.

AIM

The purpose of this study was to assess the use of an ankle arthrometer on individuals with ankle sprains.

METHODS

The participant was evaluated by the physician and the degree of ankle sprain was identified. In the prone position, the arthrometer was used to perform an anterior drawer test (uninjured before injured, 3 measures each). Both clinicians were blinded to the data of the other.

RESULTS

There were 30 participants, 10 in each group (uninjured, grade 1 sprain, grade 2 sprain). Mann-Whitney U testing found significant differences between the control and grade I ankle sprain groups (P < .001), the control and grade II ankle sprain groups (P < .001), and the grade I and grade II ankle sprain groups (P = .004). There was ±0.31-mm difference in anterior translation between healthy ankles, whereas there was 1.11- and 2.16-mm difference between ankles in grade 1 and grade 2 sprains, respectively.

CLINICAL APPLICATION

Despite the manual anterior drawer test being convenient, the subjectivity makes it unreliable. This study is consistent with prior literature about the difference in translation (millimeters) between the uninjured and injured ankles corresponding to the magnitude of ankle laxity. This study also contributes to the evolving evidence to support the relationship of a ratio of measures (injured/uninjured) as an objective measure of laxity. These comparisons to the individual's healthy ankle mitigate the variability of the normative values. The use of an arthrometer to assess ankle joint laxity enhances the objectivity of patient assessment throughout the recovery process.

LEVELS OF EVIDENCE

Level III.

Comparison of Anterior Ankle Translation With and Without Ankle Braces

BACKGROUND

Lateral ankle sprains are a common musculoskeletal injury. Ankle braces are frequently used to prevent ankle injuries.

AIM

The purpose of this study was to examine the anterior translation of the talocrural joint of 2 ankle braces relative to a control.

METHODS

Ankle mobility was assessed with the Mobil-Aider arthrometer in 3 conditions: TayCo ankle brace, Aircast ankle brace, and control. Three measures were recorded for each condition.

RESULTS

Thirty participants (9 male and 21 female patients) participated. Friedman's analysis of variance found significant between-group differences for the trial with the largest translation. Wilcoxon signed-ranks post hoc testing found significant between-group differences between the control and TayCo (P < .001) and the control and Aircast conditions (P < .001). Post hoc power analysis revealed a Kendall's W of 0.804.

CLINICAL APPLICATION

The TayCo brace is unique in that it is worn on the outside of the athletic shoe, whereas the Aircast is composed of lateral constraints worn inside the shoe. Both braces provided significant constraint over anterior talus translation when compared to control. The TayCo brace (51%-52% of control) was also significantly better than the Aircast (58%-59% of control) with less anterior translation permitted. This may be instrumental in preventing ankle injuries.

LEVEL OF EVIDENCE

2b.

Using an Arthrometer to Quantify Ankle Laxity: An Infographic Summary

Lateral ankle sprains are a common musculoskeletal injury. The anterior talofibular ligament (ATFL) is the primary ligament involved and is assessed via an anterior drawer test. Clinically assessing joint laxity has been a subjective task. Evaluating both magnitude of translation and quality of the endfeel has presented challenges. Until recently, a reliable and valid arthrometer to test joints other than the knee has not been available. The Mobil-Aider arthrometer has undergone bench testing for validity, reliability testing in healthy persons, and most recently the testing of participants for pathology. A summary of these studies is available in the Online Supplement. The goal of this study was to determine the ability of the arthrometer to objectively identify the anterior translation of the ankle and the relationship to the clinical diagnosis. The participant was evaluated by a physician and magnitude of ankle sprain was determined. An arthrometer was used to perform an anterior drawer test (uninjured before injured, 3 measures each) in the prone position. Both clinicians were blinded to the data of the other. There were 30 participants, 10 per group (uninjured, 1° sprain, 2° sprain). Mann-Whitney U testing found significant differences between the control and grade 1 ankle sprain groups (P < .001), the control and grade 2 ankle sprain groups (P < .001), and the grade 1 and grade 2 ankle sprain groups (P = .004). There was ± 0.31 mm difference in anterior translation between healthy ankles, whereas there was 1.11 mm and 2.16 mm difference between ankles in grade 1 and grade 2 sprains, respectively. The anterior drawer test is the gold standard for clinical ATFL testing, but the subjective nature of this test poses challenges. Technology is available to assess ankle joint laxity and enhance the objectivity of patient assessment and throughout the recovery process. An arthrometer is a valuable tool in quantifying orthopaedic examination.

High reproducibility of a novel supported anterior drawer test for diagnosing ankle instability

BACKGROUND

The manual traditional anterior drawer test (ADT) is essential for deciding the treatment for chronic ankle instability, but it has been shown to have a comparatively low reproducibility and accuracy, especially in less experienced hands. To clarify the inter-examiner reproducibility, we compared the actual distance of anterior translation between junior and senior examiners in ADT. We also evaluated the diagnostic abilities of traditional ADT, and a novel modified ADT (supported ADT).

METHODS

Thirty ankles were included in this study, and ankle instability was defined using stress radiography. All subjects underwent two methods of manual ADT by junior and senior examiners, and ankle instability was judged in a blinded fashion. The anterior drawer distance was calculated from the lengthening measured using a capacitance-type sensor device.

RESULTS

The degree of anterior translation determined by the junior examiner was significantly lower than that determined by the senior examiner when traditional ADT was performed (3.3 vs. 4.5 mm, P = 0.016), but there was no significant difference in anterior translation between the two examiners when supported ADT was performed (4.6 vs. 4.1 mm, P = 0.168). The inter-examiner reliability of supported ADT was higher than that of traditional ADT. For the junior examiner, the diagnostic accuracy of supported ADT was higher than that of traditional ADT (sensitivity, 0.40 vs. 0.80; specificity, 0.75 vs. 0.80).

CONCLUSION

Supported ADT may have the advantage of being a simple manual test of ankle instability with less error between examiners.

Diagnostic Accuracy of Clinical Tests Assessing Ligamentous Injury of the Talocrural and Subtalar Joints: A Systematic Review With Meta-Analysis

Context:

Ankle sprains are the most common acute musculoskeletal injury. Clinical tests represent the first opportunity to assess the sprain’s severity, but no systematic review has compared these tests to contemporary reference standards.

Objective:

To determine the diagnostic accuracy of clinical tests assessing the talocrural and subtalar joint ligaments after ankle sprain.

Data Sources:

CINAHL, EMBASE, MEDLINE, hand-searching, and PubMed-related article searches (inception to November 18, 2020).

Study Selection:

Eligible diagnostic studies compared clinical examination (palpation, joint laxity) against imaging or surgery. Studies at a high risk of bias or with high concerns regarding applicability on Quality Assessment of Diagnostic Accuracy Studies-2 were excluded from the meta-analysis.

Study Design:

Systematic review and meta-analysis.

Level of Evidence:

Level 3a.

Data Extraction:

True-positive, false-negative, false-positive, and true-negative findings were extracted to calculate sensitivity, specificity, and likelihood ratios. If ordinal data were reported, these were extracted to calculate Cohen’s kappa.

Results:

A total of 14 studies met the inclusion criteria (6302 observations; 9 clinical tests). No test had both sensitivity and specificity exceeding 90%. Palpation of the anterior talofibular ligament is highly sensitive (sensitivity 95%-100%; specificity 0%-32%; min-max; n = 6) but less so for the calcaneofibular ligament (sensitivity 49%-100%; specificity 26%-79%; min-max; n = 6). Pooled data from 6 studies (885 observations) found a low sensitivity (54%; 95% CI 35%-71%) but high specificity (87%; 95% CI 63%-96%) for the anterior drawer test.

Conclusion:

The anterior talofibular ligament is best assessed using a cluster of palpation (rule out), and anterior drawer testing (rule in). The talar tilt test can rule in injury to the calcaneofibular ligament, but a sensitive clinical test for the ligament is lacking. It is unclear if ligamentous injury grading can be done beyond the binary (injured vs uninjured), and clinical tests of the subtalar joint ligaments are not well researched. The generalizability of our findings is limited by insufficient reporting on blinding and poor study quality.

Registration:

Prospero ID: CRD42020187848.

Data Availability:

Data are available in a public, open access repository on publication, including our RevMan file and the CSV file used for meta-analysis: http://doi.org/10.5281/zenodo.4917138

Physical Examination of the Ankle: A Review of the Original Orthopedic Special Test Description and Scientific Validity of Common Tests for Ankle Examination

OBJECTIVES

To review the literature, identify and describe commonly used special tests for diagnosing injury to the ligaments of the ankle complex, present the distinguishing characteristics and limitations of each test, and discuss the current evidence for the clinical use of each test.

DATA SOURCES

Multiple PubMed (1920-2018) and CINAHL (1920-2018) searches were conducted and various musculoskeletal examination textbooks were reviewed to examine common orthopedic tests used to assess the ankle. The articles were reviewed for additional references and the search continued until the original description was found when possible.

STUDY SELECTION

All articles discussing the performance of the test or its validity (ie, sensitivity and specificity) were reviewed and summarized.

DATA EXTRACTION

Articles were reviewed for additional references and the search continued until the original description was found when possible.

DATA SYNTHESIS

The literature was reviewed, commonly used special tests for diagnosing ankle injuries were identified and described, distinguishing characteristics and limitations of each test were presented, and the current evidence for the clinical use of each test was discussed.

CONCLUSIONS

A complete physical examination is critical in the diagnosis of ankle injuries. The combination of available information such as mechanism of injury, all signs and symptoms, and changes in gait, is key to a conclusive and correct diagnosis. Clinicians should be aware of the severely limited evidence supporting the use of many commonly used special tests. Applying evidence from the literature will improve diagnostic accuracy. Further research is needed to understand the performance ability of special tests, both individually and when grouped as part of a test battery.

Use of an Instrumented Ankle Arthrometer and External Strain Gauge to Assess Ankle Dorsiflexion Motion and Plantarflexor Stiffness

BACKGROUND

Ankle dorsiflexion motion and plantarflexor stiffness measurement offer clinical insight into the assessment and treatment of musculoskeletal and neurologic disorders. We aimed to determine reliability and concurrent validity of an ankle arthrometer in quantifying dorsiflexion motion and plantarflexor stiffness.

METHODS

Ten healthy individuals were assessed for dorsiflexion motion and plantarflexor stiffness using an ankle arthrometer with a 6 degree-of-freedom kinematic linkage system and external strain gauge to apply dorsiflexion torque. Two investigators each performed five loads to the ankle at different combinations of loads (10 or 20 Nm), rates (2.5 or 5 Nm/sec), and knee angles (10° or 20°). Anteroposterior displacement and inversion-eversion rotation were also assessed with arthrometry, and functional dorsiflexion motion was assessed with the weightbearing lunge (WBL) test.

RESULTS

Good-to-excellent intrarater reliability was observed for peak dorsiflexion (intraclass correlation coefficient [ICC][2,k] = 0.949-0.988) and plantarflexor stiffness (ICC[2,k] = 0.761-0.984). Interrater reliability was good to excellent for peak dorsiflexion (ICC[2,1] = 0.766-0.910) and poor to excellent for plantarflexor stiffness (ICC[2,1] = 0.275-0.914). Reliability was best for 20-Nm loads at 5 Nm/sec. Strong correlations were observed between peak dorsiflexion and anteroposterior displacement (r = 0.666; P = 0.035) and WBL distance (r = -0.681; P = 0.036).

CONCLUSIONS

Using an ankle arthrometer to assess peak dorsiflexion and plantarflexor stiffness seems reliable when performed to greater torques with faster speeds; and offers consistency with functional measures. Use of this readily available tool may benefit clinicians attempting to quantify equinus and dorsiflexion deficits in pathological populations.

Evaluation modalities for the anatomical repair of chronic ankle instability

PURPOSE

Several evaluation modalities are reported in the literature dealing with the operative treatment of chronic ankle instability (CAI) both to establish the CAI diagnosis leading to the surgical indication and to assess the effectiveness of ankle stabilisation procedure. The purpose of this study is to present an overview of the pre- and postoperative evaluation modalities reported in the literature dealing with CAI operative treatment. The comprehensive analysis of the different modalities chosen by researchers is expected to suggest critical points in current evaluation ability of CAI surgical treatment.

METHODS

Systematic review of the literature on surgical treatment of CAI through anatomic procedures. Pubmed, Embase and Cochrane electronic databases were analysed, from 2004 to 2018.

RESULTS

One-hundred-and-four studies met inclusion in this systematic review. 88 out of 104 studies analysed preoperative mechanical laxity of the ankle to depict the ligamentous insufficiency related to the subjective feeling of functional instability. Stress radiographs and manual stress examination of the ankle were the two most common modalities to evaluate joint laxity, reported in 67 and 53 studies, respectively. Clinical Outcome Measurement Scales (COMs) is the most common evaluation modality (102 out of 104 studies) to assess CAI surgical outcome. The American Orthopaedic Foot and Ankle Society Ankle-Hindfoot scale (AOFAS) and the Karlsson score are the most frequent COMs, reported in the 66% and 33%, respectively of the included literature. The radiographic analysis of ankle laxity after stabilisation procedures is the second most frequent postoperative evaluation modality, reported in 55 out 104 studies.

CONCLUSIONS

There is a lack of standardization among researchers related to both the criteria to establish the CAI diagnosis leading to the surgical indication and the modality chosen to evaluate the effectiveness of surgical treatment. Future standardization of evaluation modalities in the CAI population is desirable to increase consistency of reported data.

LEVEL OF EVIDENCE

Level IV, review of level I, II, III and IV studies.

Functional Outcome of Modified Brostrom-Gould Procedure Using the PopLok Knotless Suture Anchor Technique in Lateral Ankle Instability

Introduction The modified Brostrom-Gould procedure is surgery to repair the lateral ligamentous complex of an ankle with chronic instability. A retrospective study was carried out among patients who had undergone this procedure at a medical center. Aim The aim of the study was to determine the mid-term functional outcome and rate of infection among patients who underwent the surgery using the PopLok® (CONMED, NY, US) Knotless Suture Anchor technique for lateral ankle instability. Methods Twenty patients who failed conservative treatment at the Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Kuala Lumpur, and who were operated on by a single surgeon from January 2011 until March 2015 were selected to participate in this study. They were examined clinically both preoperatively and postoperatively and were also evaluated using the American Foot and Ankle Score (AOFAS) and the Visual Analogue Scale (VAS). The last review of the patients, for the purpose of this study, was done at one-year postoperatively. Results The patients' overall AOFAS and VAS scores improved postoperatively as compared to the preoperative period. Preoperatively, the mean AOFAS score was 63.5 while postoperatively, the score was 93.50 (excellent score 90 - 100). The mean VAS score was 8.00 preoperatively and improved to 1.00 postoperatively. There was also an absence of infection observed one-year post-surgery. Conclusion The modified Brostrom-Gould procedure using the PopLok® Knotless Suture Anchor technique provides an excellent middle-term functional outcome and a reduction in pain for patients who failed conservative treatment, with a very low rate of infection.

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.

Effect of Kinesio® Taping on Ankle Complex Motion and Stiffness and Jump Landing Time to Stabilization in Female Ballet Dancers

Ankle sprain is the most commonly diagnosed injury experienced by ballet dancers with few studies investigating preventive support measures such as Kinesio taping. The need exists to examine the mechanical support characteristics of Kinesio taping and effect of application on ankle motion and performance. This may be important to understanding the mechanical mechanisms attributed to Kinesio ankle taping and justify its use in the prevention and treatment of jump landing injuries in ballet dancers. This study compared Kinesio taping with and without tension and no tape (control) on active and passive measures of ankle complex motion in healthy ballet dancers. A secondary objective was to examine the effect of Kinesio taping on balance using time to stabilization. Participants performed three ballet jumps with single-leg landings on a force plate across three ankle support conditions consisting of Kinesio taping, sham-Kinesio taping, and no tape. Sagittal and frontal plane motion and load-displacement of the ankle complex for each support condition were obtained using an ankle arthrometer. Kinesio taping with tension significantly restricted inversion-eversion rotation and increased inversion stiffness of the ankle complex (p < 0.05). No significant differences were found among the three ankle support conditions for jump landing time to stabilization (p > 0.05). Arthrometric results indicate Kinesio taping significantly restricted ankle complex motion in the frontal plane that is associated with lateral ankle sprain. Objective information on the nature of Kinesio taping support can assist sports medicine practitioners when recommending ankle support to athletes.

Rotational Instability after Anterior Talofibular and Calcaneofibular Ligament Section: The Experimental Basis for the Ankle Pivot Test

The clinical diagnosis of the anterior talofibular ligament (ATFL) rupture is based on the findings from the medical history and the anterior drawer test, a maneuver that allegedly pushes the talus and rearfoot anteriorly, although with great variability in its sensitivity. We consider that an ATFL rupture is best evaluated by a rotational vector (i.e., a pivot test) owing to the uncompromised medial ligaments that will block any pure anterior translation of the talus underneath the tibia. We idealized a constrained ankle cadaver model that only allows talar movements in the axial plane. Our hypothesis was that progressive sectioning of the lateral ankle ligaments in this model would cause a progressive and significant angular laxity in internal rotation. Our results showed 3.67 degrees ± 1.2 degrees of talus rotational laxity in the intact ankle, 9.6 degrees ± 3.2 degrees after ATFL sectioning, and 13.43 degrees ± 3.2 degrees after ATFL and calcaneofibular ligament sectioning, indicating almost threefold increase in internal talocrural rotation after single ATFL sectioning and an almost fourfold increase after double (ATFL and calcaneofibular ligament) sectioning. We consider this evidence of rotational ankle laxity to be a major step in defining the correct movement to diagnose an ATFL rupture and propose a new term to avoid further inconsistencies and variability, "the pivot test."

RELIABILITY OF ANKLE-FOOT MORPHOLOGY, MOBILITY, STRENGTH, AND MOTOR PERFORMANCE MEASURES

Background

Assessment of foot posture, morphology, intersegmental mobility, strength and motor control of the ankle-foot complex are commonly used clinically, but measurement properties of many assessments are unclear.

Purpose

To determine test-retest and inter-rater reliability, standard error of measurement, and minimal detectable change of morphology, joint excursion and play, strength, and motor control of the ankle-foot complex.

Design

Reliability study.

Methods

24 healthy, recreationally-active young adults without history of ankle-foot injury were assessed by two clinicians on two occasions, three to ten days apart. Measurement properties were assessed for foot morphology (foot posture index, total and truncated length, width, arch height), joint excursion (weight-bearing dorsiflexion, rearfoot and hallux goniometry, forefoot inclinometry, 1^st metatarsal displacement) and joint play, strength (handheld dynamometry), and motor control rating during intrinsic foot muscle (IFM) exercises. Clinician order was randomized using a Latin Square. The clinicians performed independent examinations and did not confer on the findings for the duration of the study. Test-retest and inter-tester reliability and agreement was assessed using intraclass correlation coefficients (ICC_2,k) and weighted kappa (K_w ).

Results

Test-retest reliability ICC were as follows: morphology: .80-1.00, joint excursion: .58-.97, joint play: -.67-.84, strength: .67-.92, IFM motor rating: K_W -.01-.71. Inter-rater reliability ICC were as follows: morphology: .81-1.00, joint excursion: .32-.97, joint play: -1.06-1.00, strength: .53-.90, and IFM motor rating: K_w .02-.56.

Conclusion

Measures of ankle-foot posture, morphology, joint excursion, and strength demonstrated fair to excellent test-retest and inter-rater reliability. Test-retest reliability for rating of perceived difficulty and motor performance was good to excellent for short-foot, toe-spread-out, and hallux exercises and poor to fair for lesser toe extension. Joint play measures had poor to fair reliability overall. The findings of this study should be considered when choosing methods of clinical assessment and outcome measures in practice and research.

Level of evidence

3.

Comparison of Magnetic Resonance Imaging and Stress Radiographs in the Evaluation of Chronic Lateral Ankle Instability

BACKGROUND

In patients who develop chronic ankle instability, clinicians often obtain magnetic resonance imaging (MRI) as part of the evaluation prior to operative referral. The purpose of this study was to analyze the diagnostic efficacy of MRI in the diagnosis of chronic lateral ankle instability. Our hypothesis was that magnetic resonance imaging would not be a specific diagnostic tool in the evaluation of chronic lateral ankle instability.

MATERIALS AND METHODS

A retrospective chart review of 187 consecutive patients (190 ankles) was performed. Inclusion criteria for the study group required a primary complaint of instability that required operative repair or reconstruction, a documented clinical evaluation consistent with instability, stress radiographs, and MRI. Stress radiographs and clinical examinations for the study group and a control group were reviewed independently by both a musculoskeletal radiologist and a board-certified orthopaedic foot and ankle surgeon. Predictive values in terms of sensitivity, specificity, and prevalence were performed. In total, 112 patients (115 ankles) were identified who underwent an operative reconstruction of their lateral ligaments with a history, physical examination, and stress radiographs consistent with lateral ankle instability. A control group was selected consisting of 75 patients seen in the foot and ankle clinic with a diagnosis other than lateral ankle instability. Thirty-seven of the patients in the control group had stress radiographs performed in the clinic to rule out instability as part of their evaluation, and this allowed for an evaluation of the efficacy of stress radiographs in addition to MRI. Statistical analysis was performed using predictive values from sensitivity, specificity, and prevalence.

RESULTS

The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) in regards to MRI in the evaluation of patients found to have clinical lateral ankle instability and those who did not had statistical significance. Sensitivity of MRI was 82.6%, specificity was 53.3%, NPV was 66.7%, and PPV was 73%. Since 37 patients in the control group also had stress radiographs, a subanalysis was performed to identify the same values with stress radiographs. Sensitivity, specificity, NPV, and PPV were 66%, 97%, 48%, and 98.7%, respectively. The overall accuracy within this study was 71% for MRI and 74% for stress radiographs.

CONCLUSION

This study demonstrated that MRI has high sensitivity but low specificity in the evaluation of clinical ankle instability. While MRI has value as a screening tool for concomitant ankle pathology, it should not be considered diagnostic in terms of lateral ankle instability.

LEVEL OF EVIDENCE

Level III, retrospective cohort, comparative series.

Three-dimensional kinematic and kinetic analysis of knee rotational stability in ACL-deficient patients during walking, running and pivoting

Background

Anterior cruciate ligament (ACL) deficiency leads to altered stability of the knee. The purpose of this study was to compare the dynamic, rotational stability of the knee, expressed as rotational stiffness, between anterior cruciate ligament-deficient (ACLD) knees, their contralateral intact knees (ACLI) and a knee healthy control group during walking, running and 90° pivoting. We hypothesized a larger tibial internal rotation, a smaller knee joint external moment and a lower rotational stiffness in the ACLD group compared to the ACLI and the control group.

Methods

Kinematic and kinetic data were collected from both legs of 44 ACLD patients and 16 healthy controls during walking, running and a pivoting maneuver (descending a staircase and immediately pivoting 90° on the landing leg). Motion data were captured using 8 high-speed cameras and a force-plate. Reflective markers were attached to bony landmarks of the lower limb and rigid clusters on the shank and thigh (CASH model). Maximum internal tibial rotation and the corresponding rotational moment were identified for all tasks and groups and used to calculate rotational stiffness (= Δmoment /Δrotation) of the knee.

Results

The tibial internal rotation of the ACLD knee was not significantly different from the ACLI knee during all three tasks. During walking and running, the tibial rotation of the control group was significantly different from both legs of the ACL-injured patient. For pivoting, no difference in tibial rotation between knees of the ACLD, ACLI and the control group was found. Knee joint external moments were not significantly different between the three groups during walking and pivoting. During running, the moments of the ACLI group were significantly higher than both the knees of the ACLD and the control group. Rotational stiffness did not differ significantly between groups in any of the three tasks.

Conclusion

A high-intensity activity combining stair descent and pivoting produces similar angular rotations, knee joint external moments and rotational stiffness in ACLD knees compared to ACLI knees and the control group. During running, the ACLI knee displayed a higher external moment than the ACLD and the healthy control group. This could indicate some type of protective strategy or muscular adaptation in the ACL-injured patients.

Four Weeks of Balance Training does not Affect Ankle Joint Stiffness in Subjects with Unilateral Chronic Ankle Instability

Background

Balance training has been shown to be effective in preventing ankle sprain recurrences in subjects with chronic ankle instability (CAI) but the biomechanical pathways underlying the clinical outcomes are still unknown. This study was conducted to determine if a 4-week balance training intervention can alter the mechanical characteristics in ankles with CAI.

Methods

Twenty-two recreationally active subjects with unilateral CAI were randomized to either a control (n = 11, 35.1 ± 9.3 years) or intervention (n = 11, 33.5 ± 6.6 years) group. Subjects in the intervention group were trained on the affected limb with static and dynamic components using a Biodex balance stability system for 4-weeks. The ankle joint stiffness and neutral zone in inversion and eversion directions on the involved and uninvolved limbs was measured at baseline and post-intervention using a dynamometer.

Results

At baseline, the mean values of the inversion stiffness (0.69 ± 0.37 Nm/degree) in the involved ankle was significantly lower (p < 0.011, 95% CI [0.563, 0.544]) than that of uninvolved contralateral ankle (0.99 ± 0.41 Nm/degree). With the available sample size, the eversion stiffness, inversion neutral zone, and eversion neutral zone were not found to be significantly different between the involved and uninvolved contralateral ankles. The 4-week balance training intervention failed to show any significant effect on the passive ankle stiffness and neutral zones in inversion and eversion.

Conclusion

Decreased inversion stiffness in the involved chronic unstable ankle was found that of uninvolved contralateral ankle. The 4-week balance training program intervention was ineffective in altering the mechanical characteristics of ankles with CAI.

Level of evidence

Randomized controlled clinical trial; Level of evidence, 1.

Examining Ankle-Joint Laxity Using 2 Knee Positions and With Simulated Muscle Guarding

CONTEXT

Several factors affect the reliability of the anterior drawer and talar tilt tests, including the individual clinician's experience and skill, ankle and knee positioning, and muscle guarding.

OBJECTIVES

To compare gastrocnemius activity during the measurement of ankle-complex motion at different knee positions, and secondarily, to compare ankle-complex motion during a simulated trial of muscle guarding.

DESIGN

Cross-sectional study.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Thirty-three participants aged 20.2 ± 1.7 years were tested.

INTERVENTION(S)

The ankle was loaded under 2 test conditions (relaxed, simulated muscle guarding) at 2 knee positions (0°, 90° of flexion) while gastrocnemius electromyography (EMG) activity was recorded.

MAIN OUTCOME MEASURE(S)

Anterior displacement (mm), inversion-eversion motion (°), and peak EMG amplitude values of the gastrocnemius (μV).

RESULTS

Anterior displacement did not differ between the positions of 0° and 90° of knee flexion (P = .193). Inversion-eversion motion was greater at 0° of knee flexion compared with 90° (P < .001). Additionally, peak EMG amplitude of the gastrocnemius was not different between 0° and 90° of knee flexion during anterior displacement (P = .101). As expected, the simulated muscle-guarding trial reduced anterior displacement compared with the relaxed condition (0° of knee flexion, P = .008; 90° of knee flexion, P = .016) and reduced inversion-eversion motion (0° of knee flexion, P = .03; 90° of knee flexion, P < .001).

CONCLUSIONS

In a relaxed state, the gastrocnemius muscle did not appear to affect anterior ankle laxity at the 2 most common knee positions for anterior drawer testing; however, talar tilt testing may be best performed with the knee in 0° of knee flexion. Finally, our outcomes from the simulated muscle-guarding condition suggest that clinicians should use caution and be aware of reduced perceived laxity when performing these clinical examination techniques immediately postinjury.

Ankle ligament laxity and stiffness in chronic ankle instability

BACKGROUND

The contribution of mechanical laxity and ligament stiffness to chronic ankle instability is unclear, particularly when using the inversion laxity test, and may have implications for diagnosis, prognosis, and treatment. Our purpose was to determine if individuals with chronic ankle instability demonstrate greater mechanical ligament laxity and altered stiffness compared to controls and copers (those with a healed sprain) during an instrumented arthrometer inversion stress test.

METHODS

Recreationally active individuals were classified as those with chronic ankle instability (n = 16), copers (n = 16), or controls (n = 16) based on injury history and self-reported score on the Cumberland Ankle Instability Tool (CAIT). Three trials of an inversion stress test were applied with an instrumented arthrometer utilizing a reliable tester. Talocrural inversion (degrees) and stiffness values were extracted. One-way ANOVAs were calculated, and Tukey post hoc testing was applied (α ≤ .05).

RESULTS

Groups were not different in age, height, or weight. The chronic ankle instability group (19 ± 6) had significantly lower CAIT scores than the control (30 ± 1) and coper (29 ± 1) groups (P < .001). The chronic ankle instability group (23 ± 12 degrees) demonstrated significantly greater inversion than the controls (13 ± 9 degrees) (P = .04) but was not significantly different than the copers (17 ± 10 degrees). No significant differences were detected in stiffness between the groups.

CONCLUSION

The chronic ankle instability group demonstrated decreased self-reported ankle function and increased mechanical laxity utilizing an instrumented arthrometer for inversion compared to the control group but not the coper group. Laxity, but not stiffness, may be a factor affecting chronic ankle instability and self-reported function.

LEVEL OF EVIDENCE

Level III, comparative study.

Increased treatment durations lead to greater improvements in non-weight bearing dorsiflexion range of motion for asymptomatic individuals immediately following an anteroposterior grade IV mobilisation of the talus

Manual therapy aims to minimise pain and restore joint mobility and function. Joint mobilisations are integral to these techniques, with anteroposterior (AP) talocrural joint mobilisations purported to increase dorsiflexion range of motion (DF-ROM). This study aimed to determine whether different treatment durations of single grade IV anteroposterior talocrural joint mobilisations elicit statistically significant differences in DF-ROM. Sixteen asymptomatic male football players (age = 27.1 ± 5.3 years) participated in the study. Non-weight bearing (NWB) and weight bearing (WB) DF-ROM was measured before and after 4 randomised treatment conditions: control treatment, 30 s, 1 min, 2 min. NWB DF-ROM was measured using a universal goniometer, and WB DF-ROM using the weight-bearing lunge test. A within-subjects design was employed so that all participants received each of the treatment conditions. A 4 × 4 balanced Latin square design and 1 week interval between sessions reduced any residual effects. Two-way repeated measures ANOVA revealed a significant improvement in DF-ROM following all AP mobilisation treatments (p < 0.001). The within subjects contrasts showed that increases in treatment duration was associated with statistically significant improvements in DF-ROM (NWB DF-ROM control = 0.01%, 30 s = 14.2%, 1 min = 21.6%, 2 min = 32.8%; WB DF-ROM control = 0.01%, 30 s = 5.0%, 1 min = 7.6%, 2 min = 10.9%; p < 0.05). However, WB DF-ROM improvements were below the minimal detectable change scores needed to conclude that improvements were not a consequence of measurement error. This research shows that single session mobilisations can elicit NWB DF-ROM improvements in asymptomatic individuals in the absence of pain, whilst increases in treatment duration confer greater improvements in NWB DF-ROM within this population.

Treatment algorithm for chronic lateral ankle instability

INTRODUCTION

ankle sprains are a common sports-related injury. A 20% of acute ankle sprains results in chronic ankle instability, requiring surgery. Aim of this paper is to report the results of a series of 38 patients treated for chronic lateral ankle instability with anatomic reconstruction.

MATERIALS AND METHODS

thirty-eight patients were enrolled in the study. Seventeen patients underwent a surgical repair using the Brostrom-modified technique, while the remaining underwent anatomic reconstruction with autologous or allogenic graft.

RESULTS

at a mean follow-up of 5 years the AOFAS score improved from 66.1 ± 5.3 to 92.2 ± 5.6.

DISCUSSION

the findings of this study confirm that anatomic reconstruction is an effective procedure with satisfactory subjective and objective results which persist at long-term follow-up along with a low complication rate. No differences, in term of clinical and functional outcomes, were observed between the Brostrom-modified repair and the anatomic reconstruction technique.

LEVEL OF EVIDENCE

level IV.

The foot and ankle examination

Most foot and ankle disorders can be diagnosed after a proper history and clinical examination and can be effectively managed in a primary care setting. It is important to assess the entirety of patient disorders that present as they can be multifactorial in cause. A broad differential should include disorders of bones, joints, muscles, neurovasculature, and surrounding soft tissue structures. Physical examination should be thorough and focused on inspection, palpation, range of motion, and appropriate special tests when applicable. This article highlights some of the salient features of the foot and ankle examination and diagnostic considerations.

Joint stability characteristics of the ankle complex after lateral ligamentous injury, part I: a laboratory comparison using arthrometric measurement

CONTEXT

The mechanical property of stiffness may be important to investigating how lateral ankle ligament injury affects the behavior of the viscoelastic properties of the ankle complex. A better understanding of injury effects on tissue elastic characteristics in relation to joint laxity could be obtained from cadaveric study.

OBJECTIVE

To biomechanically determine the laxity and stiffness characteristics of the cadaver ankle complex before and after simulated injury to the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) during anterior drawer and inversion loading.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Seven fresh-frozen cadaver ankle specimens.

INTERVENTION(S)

All ankles underwent loading before and after simulated lateral ankle injury using an ankle arthrometer.

MAIN OUTCOME MEASURE(S)

The dependent variables were anterior displacement, anterior end-range stiffness, inversion rotation, and inversion end-range stiffness.

RESULTS

Isolated ATFL and combined ATFL and CFL sectioning resulted in increased anterior displacement but not end-range stiffness when compared with the intact ankle. With inversion loading, combined ATFL and CFL sectioning resulted in increased range of motion and decreased end-range stiffness when compared with the intact and ATFL-sectioned ankles.

CONCLUSIONS

The absence of change in anterior end-range stiffness between the intact and ligament-deficient ankles indicated bony and other soft tissues functioned to maintain stiffness after pathologic joint displacement, whereas inversion loading of the CFL-deficient ankle after pathologic joint displacement indicated the ankle complex was less stiff when supported only by the secondary joint structures.

Joint stability characteristics of the ankle complex in female athletes with histories of lateral ankle sprain, part II: clinical experience using arthrometric measurement

CONTEXT

This is part II of a 2-part series discussing stability characteristics of the ankle complex. In part I, we used a cadaver model to examine the effects of sectioning the lateral ankle ligaments on anterior and inversion motion and stiffness of the ankle complex. In part II, we wanted to build on and apply these findings to the clinical assessment of ankle-complex motion and stiffness in a group of athletes with a history of unilateral ankle sprain.

OBJECTIVE

To examine ankle-complex motion and stiffness in a group of athletes with reported history of lateral ankle sprain.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Twenty-five female college athletes (age = 19.4 ± 1.4 years, height = 170.2 ± 7.4 cm, mass = 67.3 ± 10.0 kg) with histories of unilateral ankle sprain.

INTERVENTION(S)

All ankles underwent loading with an ankle arthrometer. Ankles were tested bilaterally.

MAIN OUTCOME MEASURE(S)

The dependent variables were anterior displacement, anterior end-range stiffness, inversion rotation, and inversion end-range stiffness.

RESULTS

Anterior displacement of the ankle complex did not differ between the uninjured and sprained ankles (P = .37), whereas ankle-complex rotation was greater for the sprained ankles (P = .03). The sprained ankles had less anterior and inversion end-range stiffness than the uninjured ankles (P < .01).

CONCLUSIONS

Changes in ankle-complex laxity and end-range stiffness were detected in ankles with histories of sprain. These results indicate the presence of altered mechanical characteristics in the soft tissues of the sprained ankles.

The effects of ankle Kinesio taping on ankle stiffness and dynamic balance

The purpose of this study was to determine the effects of Kinesio® taping on static restraint and dynamic postural control of the ankle joint. Thirty female subjects with no history of ankle injury participated in this study. Subjects were tested for passive ankle laxity and stiffness, and time to stabilization following forward, backward, medial, and lateral hops. Subjects were tested prior to tape application, immediately following application, and following 24 hours of use. Differences between taping conditions were investigated using analyses of variance and pairwise comparisons. Stiffness increased following initial application and 24 hours of Kinesio® tape use (F = 6.99, p = .003), despite no observed changes in ankle laxity (F = 0.77, p = .49); however, no changes were observed in time-to-stabilization (F = 0.03, p = .97). Our results suggest that Kinesio® tape may improve static restraint in the ankle joint without altering peak motion or dynamic postural control. A future investigation into Kinesio® tape efficacy in injury prevention or rehabilitation is warranted.

Quantitative evaluation of the viscoelastic properties of the ankle joint complex in patients suffering from ankle sprain by the anterior drawer test

PURPOSE

Biological tissues such as ligaments exhibit viscoelastic behaviours. Injury to the ligament may induce changes of these viscoelastic properties, and these changes could serve as biomarkers to detect the injury. In the present study, a novel instrument was developed to non-invasive quantify the viscoelastic properties of the ankle in vivo by the anterior drawer test. The purpose of the study was to investigate the reliability of the instrument and to compare the viscoelastic properties of the ankle between patients suffering from ankle sprain and controls.

METHODS

Eight patients and eight controls participated in the present study. The reliability test was performed on three randomly chosen subjects. In patient and control test, both ankles of each subject were tested to evaluate the viscoelastic properties of the ankle. The viscosity index was defined for quantitatively evaluating the viscosity of the ankle. Greater viscosity index was associated with lower viscosity. Injured and uninjured ankles of patient and both ankles of controls were compared.

RESULTS

The instrument exhibited excellent test-retest reliability (r > 0.9). Injured ankles exhibited significantly less viscosity than uninjured ankles, since injured ankles of patients had significantly higher viscosity index (8,148 ± 5,266) compared with uninjured ankles of patients (948 ± 617; p = 0.008) and controls (1,326 ± 613; p < 0.001).

CONCLUSIONS

The study revealed that the viscoelastic properties of the ankle can serve as sensitive and useful clinical biomarkers to differentiate between injured and uninjured ankles. The method may provide a clinical examination for objectively evaluating lateral ankle ligament injuries.

Comparison of ankle arthrometry to stress ultrasound imaging in the assessment of ankle laxity in healthy adults

PURPOSE/BACKGROUND

Ultrasonography (US) may aid the assessment of the anterior talofibular ligament (ATFL) injury after lateral ankle sprains by allowing the clinician to visualize and measure talocrural laxity. Comparison of US against another objective method of ankle laxity assessment, such as ankle arthrometry (AA), is needed. The purpose was to evaluate the relationship between the ATFL length measurements measured from stress US images to the inversion and anterior drawer displacement measured with AA in healthy subjects.

METHODS

This descriptive laboratory study included 26 ankles from healthy subjects. The apparent length of the ATFL was measured using US during anterior drawer (USAD) and inversion (USINV) stress and the translation of the talocrural joint was measured using AA during anterior drawer (AAAD) and inversion (AAINV) stress. Percent change in length for USAD and USINV were quantified. Intraclass correlation coefficients and pearson product moment correlations Bland-Altman limits of agreement were calculated between relevant variables.

RESULTS

USAD and USINV percent change in length were positively correlated (r = .76). Bland Altman analysis revealed a mean difference of 5.38 mm (95% CI: -3.5 to 12 mm) with the AAAD producing higher values than the USAD. No significant correlations were found between the US and AA variables, however the absolute AAAD and AAINV variables were also positively correlated (r = .61).

CONCLUSIONS

The US and AA variables were not directly correlated when measuring inversion and anterior laxity in healthy ankles. Differences between the devices that may affect this include different rates of joint loading, patient position and method of assessing laxity. The AA results demonstrated greater anterior displacement. Results may differ in ankle injured subjects who may demonstrate increases in anteroposterior and inversion laxity.

LEVEL OF EVIDENCE

2b. Exploratory study in healthy cohort.

The effect of collateral ligament release on ankle dorsiflexion: an anatomical study

BACKGROUND

Ankle stiffness is a common complication after ankle fracture, reconstructive surgery or total ankle replacement, and the usual limitation is in dorsiflexion. There are few articles in the literature concerning this frequent problem, and furthermore they are not recent and tend to be controversial. The purpose of this anatomical study was to evaluate and quantify the effect of ankle collateral ligament release on dorsiflexion, specifically the amount of increase in ankle dorsiflexion following section of the two ligaments most often implicated in ankle stiffness: the deep posterior tibiotalar ligament (dPTTaL, or posterior deep deltoid) and the posterior talofibular ligament (PTaFL).

METHODS

We dissected 18 adult fresh cadaveric ankle joints, and with an electronic goniometer combined with an electronic dynamometer measured their mobility in dorsiflexion before and after transection of each ligament separately, and the two ligaments combined.

RESULTS

The results showed a significant difference between the two groups of ankles with section of the dPTTaL resulting in a greater increase in ankle dorsiflexion than section of the PTaFL (mean 7.45° vs. 3.5°, respectively; p<0.001). Combined section of both ligaments improved the gain in ankle dorsiflexion more than isolated section of each ligament, but was not statistically significant (p=0.88).

CONCLUSION

If after gastrocnemius recession or Achilles tendon lengthening persistent restriction remains in ankle dorsiflexion, the results of our study demonstrate that the next step should be release of the dPTTaL.

Arthrometric measurement of ankle-complex motion: normative values

CONTEXT

Valid and reliable measurements of ankle-complex motion have been reported using the Hollis Ankle Arthrometer. No published normative data of ankle-complex motion obtained from ankle arthrometry are available for use as a reference for clinical decision making.

OBJECTIVE

To describe the distribution variables of ankle-complex motion in uninjured ankles and to establish normative reference values for use in research and to assist in clinical decision making.

DESIGN

Descriptive laboratory study.

SETTING

University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Both ankles of 50 men and 50 women (age = 21.78 ± 2.0 years [range, 19-25 years]) were tested.

INTERVENTION(S)

Each ankle underwent anteroposterior (AP) and inversion-eversion (I-E) loading using an ankle arthrometer.

MAIN OUTCOME MEASURE(S)

Recorded anterior, posterior, and total AP displacement (millimeters) at 125 N and inversion, eversion, and total I-E rotation (degrees) at 4 Nm.

RESULTS

Women had greater ankle-complex motion for all variables except for posterior displacement. Total AP displacement of the ankle complex was 18.79 ± 4.1 mm for women and 16.70 ± 4.8 mm for men (U = 3742.5, P < .01). Total I-E rotation of the ankle complex was 42.10 degrees ± 9.0 degrees for women and 34.13 degrees ± 10.1 degrees for men (U = 2807, P < .001). All variables were normally distributed except for anterior displacement, inversion rotation, eversion rotation, and total I-E rotation in the women's ankles and eversion rotation in the men's ankles; these variables were skewed positively.

CONCLUSIONS

Our study increases the available database on ankle-complex motion, and it forms the basis of norm-referenced clinical comparisons and the basis on which quantitative definitions of ankle pathologic conditions can be developed.

Clinical evaluation of a new noninvasive ankle arthrometer

INTRODUCTION

A nonradiographic arthrometer was developed to objectively quantify anterior talar drawer instability in stable and unstable ankles. Diagnostic validity of this device was previously demonstrated in a cadaver study. The aim of the present study was to validate the ankle arthrometer in an in vivo setting.

METHODS

Twenty-three subjects participated in the study. An orthopedic surgeon first performed a manual anterior talar drawer test to classify the subjects' ankles as stable or unstable. The subjects were then evaluated using the ankle arthrometer, and filled out a validated self-reported questionnaire (German version of the Foot and Ankle Ability Measure [FAAM-G]). Ankle stiffness was calculated from the low linear region (40-60 N) of the load deformation curves obtained from the ankle arthrometer. Reliability testing of these stiffness values was done based on load deformation curves, with 150 and 200 N maximum anterior drawer loads applied in the ankle arthrometer.

RESULTS

Using the manual anterior drawer test, 16 ankles were classified as stable and 7 were classified as unstable. Arthrometer stiffness analysis differentiated stable from unstable ankles (P = 0.00 and P = 0.01, respectively). Test-retest demonstrated an accurate reliability (intraclass correlation coefficient = 0.80). A significant correlation was found between both FAAM-G subscales and the arthrometer stiffness values (r = 0.43 and 0.54; P = 0.04 and 0.01). Discussion Subjects with and without mechanical ankle instability could be differentiated by ankle arthrometer stiffness analysis and the FAAM-G questionnaire results. This nonradiographic device may be relevant for screening athletes at risk for ankle injuries, for clinical follow-up studies, and implementing preventive strategies.

CONCLUSION

Validity and reliability of the new ankle arthrometer is demonstrated in a small cohort in an in vivo setting.

Soft-tissue ankle injuries

Soft-tissue ankle injuries are extremely common and frequently present in the emergency department or to the general practitioner. The lateral ligament complex is most commonly affected, usually following an injury with the ankle in an inverted, plantar-flexed position. The diagnosis is usually clinical, and delayed examination and reassessment 3—5 days after injury is recommended as pain and swelling hinder accurate assessment immediately following injury. Applying the Ottawa ankle rules can reduce the number of unnecessary radiographs. Treatment is usually non-operative with the focus on controlling ankle swelling and pain, and early restoration of ankle movements. Surgical repair of ligaments may be indicated in certain cases, though the role of surgery in the acute setting remains unclear. In the present review, we discuss the anatomy, mechanism of injury, risk factors, clinical presentation, diagnosis, treatment and outcome of soft-tissue ankle injuries as well as consider how such injuries may be prevented.

Clinical evaluation of a dynamic test for lateral ankle ligament laxity

The dynamic anterior ankle tester (DAAT) has shown a good reliability in testing anterior talar translation in earlier studies. The goal of the present study was first to evaluate the reliability of the DAAT in a clinical setting and second to analyze its ability to detect increased ligament laxity. In 39 patients with unilateral chronic lateral ankle instability, the anterior talar translation of the affected and non-affected side was measured pre and postoperatively using the DAAT, Telos stress radiographs, and the manual anterior drawer test. In contrast to both other tests, the DAAT was not able to accurately detect increased ligament laxity preoperatively or decreased laxity of the affected ankle postoperatively. The DAAT showed a low sensitivity to change (the difference between the mean pre and postoperative value) and a low reliability compared to both other tests. There were no correlations between the three tests. In conclusion, the DAAT showed a low reliability in effectively testing lateral ankle ligament laxity in a clinical setting. This is in contrast to earlier evaluations.