A comparison of MRI and clinical examination of acute lateral ankle sprains

A Review of Chronic Lateral Ankle Instability and Emerging Alternative Outcome Monitoring Tools in Patients following Ankle Ligament Reconstruction Surgery

Ankle sprains are exceedingly common injuries in both athletes and the general population. They account for 10 to 30% of all sports injuries. Although the vast majority of lateral ankle ligament injuries respond successfully to conservative management, the absolute number of those that progress to chronic lateral ankle instability (CLAI) remains considerably important. This condition is characterized by persistent symptoms and may be associated with short-term and long-term complications and functional deficits. There is still a lack of ideal postoperative management of CLAI patients. Furthermore, an evidence-based rehabilitation phasing does not exist and most of the published studies regarding this subject suggest some protocols based on a wide variety of functional assessment scores and other modalities that are not accurate enough. Moreover, the literature that assesses the ability to return to work (RTW) and return to sport (RTS) in the general population and athletes operated for CLAI most commonly shows aggregated results with global rates of RTW or RTS without describing a detailed timeline based on the readiness of patients to return to each level of activity. Although stress radiographs and MRI have been assessed as potential tools to improve postoperative management of CLAI patients, the first modality is limited by its low sensitivity to detect laxity and the second one by its static character and its inability to predict neither the healing process phase nor the mechanical properties of the repaired/reconstructed ligaments. Bioelectrical impedance, mechanical impedance and near-infrared spectroscopy are non-invasive methods of measurement that could be potential assessment tools to help surgeons improve the postoperative management of patients after CLAI surgery.

Diagnostic value of measuring the talofibular space using stress sonography in chronic lateral ankle instability

OBJECTIVES

To investigate the diagnostic value of measuring the talofibular space using stress sonography for chronic lateral ankle instability (CLAI).

MATERIALS & METHODS

We recruited patients who were clinically diagnosed with CLAI between October 2018 and December 2019 (CLAI group). A control group of healthy volunteers was also included for this study. Both groups underwent a preliminary stress sonographic examination. First, the ultrasonic characteristics of the anterior talofibular ligament (ATFL), including length, thickness, relaxation, calcification, and rupture, were observed using conventional sonography. Second, the talofibular space at the passive neutral position (D1) and maximum varus position (D2) was measured (by stress sonographic images), and the difference (ΔD = D1-D2) between them was determined. Third, the parameters of the two groups were statistically compared. Finally, receiver operating characteristic (ROC) curves and area under the curve (AUC) analyses were performed for parameters with significant differences.

RESULTS

The CLAI group comprised 60 patients, yielding data on 60 ankles, whereas the control group comprised 35 participants, yielding data for 70 ankles. Differences in D1, D2, and ΔD of the talofibular space between the two groups were significant, with ΔD proving to be the best diagnostic indicator (P < 0.001). Its AUC, optimal cutoff value, sensitivity, and specificity were 0.922, 0.11 cm, 73 %, and 94 %, respectively, followed by D2 (0.850, 0.47 cm, 67 %, and 94 %, respectively; P < 0.001) and D1 (0.635, 0.47 cm, 67 %, and 94 %, respectively; P = 0.006).

CONCLUSION

Measurement of talofibular space in stress sonography is a valuable diagnostic indicator for CLAI, especially the ΔD between the neutral and stress position.

Physical Examination of Ankle Sprain and Ankle Instability: Can We Really Divide It into Low and High Ankle Sprains?

Lateral ankle ligament sprains and syndesmotic injuries are two different entities. However, they may be combined under the same spectrum depending on the arch of violence during the injury. Currently, the clinical examination has a limited value in the differential diagnosis between an acute anterior talofibular ligament rupture and a syndesmotic high ankle sprain. However, its use is indispensable for raising a high index of suspicion for detecting these injuries. Based on the mechanism of injury, clinical examination plays an essential role in guiding further imaging and early diagnosis of low/high ankle instability.

Lateral ankle instability - repair/ reconstruct what's new

Lateral ankle instability is a common condition which responds well to non-surgical management. However, the chronic symptomatic instability may require surgical intervention. The acceptable and practiced procedure is the Brostom Gould modification and it has a high patient satisfaction score. However, the current understanding and newer techniques for stabilising the lateral ligament complex has resulted in arthroscopic repairs, augmentation and tendon graft reconstructions. The literature does not provide an answer to the efficacy of these new techniques but there is some preliminary information favouring some of the latest procedures. It is now accepted practise to include ankle arthroscopy as a pre repair step. Augmentation of anatomical repair is also favoured in a select group of patients. This article provides an up to date account of the newer techniques for lateral ankle stabilisation.

Ankle instability – review and new trends

Ankle instability is an old topic with increasing importance in Orthopaedics’ world, as we start now realising how underdiagnosed this pathology has been. A lot of effort has been made in recent years to better understand the pathomechanics of this injury, with new surgical techniques being tried and even new anatomic structures being described. The objective of this paper is to review and compile the most important and recent literature on this matter, in an academic way, but oriented to clinical practice, so it can help surgeons keep updated in this so important subject.

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

Acute ankle sprain in athletes: Clinical aspects and algorithmic approach

Acute ankle sprain is the most common lower limb injury in athletes and accounts for 16%-40% of all sports-related injuries. It is especially common in basketball, American football, and soccer. The majority of sprains affect the lateral ligaments, particularly the anterior talofibular ligament. Despite its high prevalence, a high proportion of patients experience persistent residual symptoms and injury recurrence. A detailed history and proper physical examination are diagnostic cornerstones. Imaging is not indicated for the majority of ankle sprain cases and should be requested according to the Ottawa ankle rules. Several interventions have been recommended in the management of acute ankle sprains including rest, ice, compression, and elevation, analgesic and anti-inflammatory medications, bracing and immobilization, early weight-bearing and walking aids, foot orthoses, manual therapy, exercise therapy, electrophysical modalities and surgery (only in selected refractory cases). Among these interventions, exercise and bracing have been recommended with a higher level of evidence and should be incorporated in the rehabilitation process. An exercise program should be comprehensive and progressive including the range of motion, stretching, strengthening, neuromuscular, proprioceptive, and sport-specific exercises. Decision-making regarding return to the sport in athletes may be challenging and a sports physician should determine this based on the self-reported variables, manual tests for stability, and functional performance testing. There are some common myths and mistakes in the management of ankle sprains, which all clinicians should be aware of and avoid. These include excessive imaging, unwarranted non-weight-bearing, unjustified immobilization, delay in functional movements, and inadequate rehabilitation. The application of an evidence-based algorithmic approach considering the individual characteristics is helpful and should be recommended.

Lateral Ligament Instability: Review of Pathology and Diagnosis

PURPOSE OF REVIEW

Ankle sprains are a common injury that can lead to chronic lateral ankle instability resulting in pain, poor function, and decreased quality of life. The purpose of this review is to present information regarding injury mechanisms to the lateral ligaments of the ankle and the necessary steps to appropriately diagnose lateral ligament instability.

RECENT FINDINGS

The literature demonstrates that history and physical examination is often a reliable method for diagnosis of lateral ankle instability. In addition, imaging modalities are often used as adjuncts for diagnosis, especially when physical exam findings are equivocal. In summary, chronic lateral ligament instability of the ankle occurs secondary to failure of the lateral ligamentous complex. A focused physical examination to evaluate the anterior talofibular ligament, calcaneofibular ligament, and posterior talofibular ligament is necessary for diagnosis. Imaging modalities including plain radiographs, stress radiographs, and MRI are helpful for definitive diagnosis and to rule out other pathology.

Magnitude and variability of gait characteristics when walking on an irregular surface at different speeds

Different modes of perturbations have been used to understand how individuals negotiate irregular surfaces, with a general notion that increased locomotion variability induces a positive training stimulus. Individuals tend to walk slower when initially exposed to such locomotion tasks, potentially influencing the magnitude and variability of biomechanical parameters. This study investigated theeffects of gait speed on lower extremity biomechanics when walking on an irregular (IS) and regular surface (RS). Twenty physically active males walked on a RS and IS at three different speeds (4 km/h, 5 km/h, 6 km/h). Lower extremity kinematics (300 Hz) and surface electromyography (3000 Hz) were recorded during the first 90 s of gait. Two-factor repeated measures ANOVA was used to determine surface and speed effects (p < 0.05). Gait speed influences walking biomechanics (kinematic and muscle activity parameters) the same irrespective of surface condition. As walking speed increased, sagittal shoe-surface angle, maximum ankle inversion, ankle abduction, knee and hip flexion increased during stance phase when walking on the IS and RS (p < 0.05). Increasing walking speed caused increased muscle activity of the tibialis anterior, peroneus longus, gastrocnemius medialis, vastus medialis and biceps femoris (p < 0.05) on the IS and RS during the gait cycle. Increased gait, kinematic and muscle activity variability was reported at lower walking speed on both the IS and RS. Further, irrespective of gait speed, walking on an IS triggers postural adjustments, higher muscle activity and increased gait variability compared to RS walking. Our findings suggest the benefits of training on the irregular surface may be further enhanced at slower gait speeds.

MRI of the anterior talofibular ligament, talar cartilage and os subfibulare: Comparison of isotropic resolution 3D and conventional 2D T2-weighted fast spin-echo sequences at 3.0 T

PURPOSE

To determine the accuracy of a three-dimensional (3D) T2-weighted fast spin-echo (FSE) magnetic resonance (MR) sequence compared with two-dimensional (2D) sequence for diagnosing anterior talofibular ligament (ATFL) tears, chondral lesion of the talus (CLT) and os subfibulare/avulsion fracture of the distal fibula (OSF).

MATERIALS AND METHODS

Thirty-five patients were included, who had undergone ankle MRI with 3D T2-weighted FSE and 2D T2-weighted FSE sequences, as well as subsequent ankle arthroscopy, between November 2013 and July 2014. Each MR imaging sequence was independently scored by two readers retrospectively for the presence of ATFL tears, CLT and OSF. The area under the receiver operating curve (AUC) was compared to determine the discriminatory power of the two image sequences. Interobserver agreement was expressed as unweighted kappa value.

RESULTS

Arthroscopic findings confirmed 21 complete tears of the ATFL, 14 partial tears of the ATFL, 17 CLTs and 7 OSFs. There were no significant differences in the diagnoses of ATFL tears (p = 0.074-0.501), CLT (p = 0.090-0.450) and OSF (p = 0.317) obtained from the 2D and 3D sequences by either reader. The interobserver agreement rates between two readers using the 3D T2-weighted FSE sequence versus those obtained with the 2D sequence were substantial (κ = 0.659) versus moderate (κ = 0.553) for ATFL tears, moderate (κ = 0.499) versus substantial (κ = 0.676) for CLT and substantial (κ = 0.621) versus substantial (κ = 0.689) for OSF.

CONCLUSION

Three-dimensional isotropic T2-weighted FSE MRI of the ankle resulted in no statistically significant difference in diagnostic performance compared to two-dimensional T2-weighted FSE MRI in the evaluation of ATFL tears, CLTs and OSFs.

Differences between mechanically stable and unstable chronic ankle instability subgroups when examined by arthrometer and FAAM-G

Background

The objective measurement of the mechanical component and its role in chronic ankle instability is still a matter of scientific debate. We analyzed known group and diagnostic validity of our ankle arthrometer. Additionally, functional aspects of chronic ankle instability were evaluated in relation to anterior talar drawer.

Methods

By manual stress testing, 41 functionally unstable ankles were divided as mechanically stable (n = 15) or mechanically unstable (n = 26). Ankle laxity was quantified using an ankle arthrometer. Stiffness values from the load displacement curves were calculated between 40 and 60 N. Known group validity and eta² were established by comparing manual and arthrometer testing results. Diagnostic validity for the ankle arthrometer was determined by a 2 × 2 contingency table. The functional ankle instability severity was quantified by the German version of the Foot and Ankle Ability Measure (FAAM-G). Stiffness (40–60 N) and FAAM-G values were correlated.

Results

Mechanically unstable ankles had lower 40–60 N stiffness values than mechanically stable ankles (p = 0.006 and <0.001). Eta for the relation between manual and arthrometer anterior talar drawer testing was 0.628. With 5.1 N/mm as cut-off value, accuracy, sensitivity, and specificity were 85%, 81%, and 93%, respectively.

The correlation between individual 40–60 N arthrometer stiffness values and FAAM-G scores was r = 0.286 and 0.316 (p = 0.07 and 0.04).

Conclusions

In this investigation, the ankle arthrometer demonstrated a high diagnostic validity for the determination of mechanical ankle instability. A clear interaction between mechanical (ankle arthrometer) and functional (FAAM-G) measures could not be demonstrated.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-015-0171-2) contains supplementary material, which is available to authorized users.

Fibular malalignment in individuals with chronic ankle instability

STUDY DESIGN

Case series.

OBJECTIVES

To determine whether abnormal fibular alignment is present in individuals with chronic ankle instability (CAI) using 3-D analysis of computed tomography (CT)-based bone models.

BACKGROUND

A positional difference of the distal fibula in individuals with unilateral CAI, when compared to the contralateral side, has been suggested. However, previous studies report no consistent pattern of fibular malalignment in the anteroposterior direction and, to our knowledge, no study has investigated mediolateral malalignment.

METHODS

Seventeen males with unilateral CAI (mean ± SD age, 21.0 ± 2.4 years) and no history of injury in the contralateral side were enrolled. Geometric bone models of the tibia and fibula were created from non-weight-bearing CT images, and anatomical coordinate systems were embedded in the tibia model. Bilateral tibiae were superimposed using a best-fit algorithm that moved the tibia to the position of best congruity, and the amount of side-to-side difference in position of the fibulae was measured. The anteroposterior and mediolateral positional difference of the fibula of the ankle with CAI relative to the contralateral ankle, for the distal 10 cm of the fibula length, was determined using a color-coded map.

RESULTS

The fibula of the ankle with CAI was significantly more lateral (0.57-0.68 mm) than that of the contralateral healthy ankle at all reference points from distal 10 cm to the lateral malleolus. There was no significant difference in anteroposterior position between the healthy ankles and those with CAI.

CONCLUSION

This study detected malalignment of the distal fibula in ankles with CAI in a non-weight-bearing position. The fibula of the ankles with CAI had a significantly more lateral position than that of the healthy ankles, which may contribute to recurrent lateral ankle sprain or giving-way episodes.

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.

Associations between MRI findings and symptoms in patients with chronic ankle sprain

Magnetic resonance imaging (MRI) provides an accurate method of observing and diagnosing injuries of the ligament complex of the ankle. However, the association between ankle symptoms and MRI findings has been unclear. The purpose of the present study was to evaluate the relationship between ankle pain and MRI findings. This prospective study included 40 patients with ankle pain after inversion injury and 10 healthy volunteers. Correlations among the ankle symptoms (tenderness on the anterior talofibular ligament, pain during varus stress in a neutral and plantarflexed ankle), and MRI findings were analyzed. A complete tear of the anterior talofibular ligament correlated with ankle pain during varus stress in the neutral position (r = 0.365, p = .031) and tenderness at the anterior talofibular ligament (r = 0.362, p = .032). The results of our study suggest that a complete tear of the anterior talofibular ligament will correlate with lateral ankle pain.

The Anatomic Pattern of Injuries in Acute Inversion Ankle Sprains: A Magnetic Resonance Imaging Study

Background:

There are little data on the incidence and patterns of injuries seen on magnetic resonance imaging (MRI) in acute inversion ankle sprains. This study may help in the understanding of the pathomechanics, natural history, and outcomes of this common injury.

Study Design:

Case series; Level of evidence, 4.

Methods:

From June 2011 to June 2013, a total of 64 consecutive patients had MRI of the ankle performed for acute inversion injury to the ankle. All injuries/pathologies reported were recorded.

Results:

Only 22% of patients had isolated lateral ligament complex injuries. Twenty-two percent of patients had other pathologies but no lateral ligament injury, and 53% had lateral ligament injuries in combination with other pathologies or injuries. The most common associated finding with lateral ligament injuries was bone bruising (76%) followed by deltoid ligament injury (50%). The overall incidence of bone bruising was 50%. Thirty percent of ankles had tendon pathology, 27% had deltoid ligament injury, and 22% had occult fractures.

Conclusion:

Isolated lateral ligament ankle injury is not as common as is believed. The pattern of injury seems complex, and most patients appear to have more injuries than expected. MRI reveals additional information that may have significance in terms of diagnosis, treatment, and prognosis in this common injury.

Incidence of talar dome lesions with concomitant peroneal tendon pathologic features: a magnetic resonance imaging evaluation

Few studies have evaluated the incidence of talar dome lesions and injuries to the peroneal tendons occurring concomitantly. The purpose of our research was to evaluate the incidence of osteochondral lesions of the talus (OLT) with peroneal tendon pathologic features according to the magnetic resonance imaging (MRI) findings. A database search was conducted in the Department of Radiology at the Western Pennsylvania Hospital and Forbes Regional Campus for all MRI examinations ordered by attending physicians of the Department of Foot and Ankle Surgery from 2008 to 2010. A total of 810 MRI reports were reviewed, of which 198 contained a diagnosis of peroneal tendon pathologic features (e.g., tenosynovitis, split tears) or OLT (i.e., chondral, osteochondral, subchondral edema, cystic changes), or both. MRI scans were then reviewed to confirm the report findings and findings not identified in the report. A total of 76 patients were identified as having an OLT. Of these 76 patients, 49 had associated peroneal tendon pathologic features. MRI evaluation revealed that 49 (65.3%) of the 76 patients with a talar dome lesion had concomitant peroneal pathologic features. Talar dome lesions with concomitant tears/tendinopathy of the peroneus brevis were associated in 14.6%. The incidence of an OLT with tears/tenosynovitis of the peroneus longus was 10.6%, because tears/tendinopathy of both peroneal tendons was present in 18.6%. Tenosynovitis of the brevis and longus were seen in 21.3% of those with an OLT. Our findings suggest the need for an increased level of suspicion for injuries to the lateral ankle ligaments, peroneal tendon complex, and ankle joint when evaluating a patient with ankle instability and chronic pain.

In vivo cartilage contact strains in patients with lateral ankle instability

Damage to the anterior talofibular ligament (ATFL) and cacaneofibular ligament (CFL) during an ankle sprain may be linked to the development of osteoarthritis. Although altered tibiotalar kinematics have been demonstrated, the effects of lateral ankle instability (LAI) on in vivo cartilage strains have not been described. We hypothesized that peak cartilage strains increase, and the location is shifted in patients with ATFL injuries. We used 3-D MRI models and biplanar fluoroscopy to evaluate in vivo cartilage contact strains in seven patients with unilateral LAI. Subjects had chronic unilateral ATFL injury or combined ATFL and CFL injury, and were evaluated with increasing load while stepping onto a force plate. Peak cartilage strain and the location of the peak strain were measured using the contralateral normal ankle as a control. Ankles with LAI demonstrated significantly increased peak strain when compared with ATFL-intact controls. For example, at 100% body weight, peak strain was 29+/-8% on the injured side compared to 21+/-5% on the intact side. The position of peak strain on the injured ankle also showed significant anterior translation and medial translation. At 100% body weight, the location of peak strain in the injured ankle translated anteriorly by 15.5+/-7.1mm and medially by 12.9+/-4.3mm relative to the intact ankle. These changes correspond to the region of clinically observed osteoarthritis. Chronic LAI, therefore, may contribute to the development of tibiotalar cartilage degeneration due to altered cartilage strains.

Reliability of MRI findings of peroneal tendinopathy in patients with lateral chronic ankle instability

BACKGROUND

Patients with chronic lateral ankle instability also have peroneal tendinopathy often. However, preoperative MRIs of these patients are vague in many cases. Our study was performed to see the reliability of MRI findings of peroneal tendinopathy in patients with chronic lateral ankle instability.

METHODS

MRI images for 82 patients who had chronic lateral ankle instability, and had received surgical treatment between March 2006 and November 2009 were compared with impressions from operating rooms. The mean age of patients was 36.4 years (range, 15 to 64 years), 82 ankles were studied, and patients with rheumatoid diseases were excluded from the study.

RESULTS

Of the 82 cases, 26 were true positives, 38 true negatives, 13 false positives and 5 false negatives. Of 39 cases of peroneal tendinopathy diagnosed from MRI, 14 had peroneal tendon partial tears, 15 tenosynovitis, 3 dislocations, 17 low-lying muscle bellies, and 6 peroneus quartus muscles. Of 31 cases of peroneal tendinopathy observed in surgery 11 had peroneal tendon partial tears, 4 tenosynovitis, 5 dislocations, 12 low-lying muscle belliess, and 1 peroneus quartus muscle. Sensitivity and specificity of peroneal tendinopathy were 83.9% and 74.5%, respectively. Positive predictive value was 66.7%. Negative predictive value was 88.4%. Accuracy rate was 78.0%.

CONCLUSIONS

MRI is a useful diagnostic tool for detecting peroneal tendinopathy in patients with chronic lateral ankle instability. However, MRI is vague in many cases. Therefore, a thorough delicate physical examination and careful observation is needed.

Reliability of MRI findings of peroneal tendinopathy in patients with lateral chronic ankle instability

BACKGROUND

Patients with chronic lateral ankle instability also have peroneal tendinopathy often. However, preoperative MRIs of these patients are vague in many cases. Our study was performed to see the reliability of MRI findings of peroneal tendinopathy in patients with chronic lateral ankle instability.

METHODS

MRI images for 82 patients who had chronic lateral ankle instability, and had received surgical treatment between March 2006 and November 2009 were compared with impressions from operating rooms. The mean age of patients was 36.4 years (range, 15 to 64 years), 82 ankles were studied, and patients with rheumatoid diseases were excluded from the study.

RESULTS

Of the 82 cases, 26 were true positives, 38 true negatives, 13 false positives and 5 false negatives. Of 39 cases of peroneal tendinopathy diagnosed from MRI, 14 had peroneal tendon partial tears, 15 tenosynovitis, 3 dislocations, 17 low-lying muscle bellies, and 6 peroneus quartus muscles. Of 31 cases of peroneal tendinopathy observed in surgery 11 had peroneal tendon partial tears, 4 tenosynovitis, 5 dislocations, 12 low-lying muscle belliess, and 1 peroneus quartus muscle. Sensitivity and specificity of peroneal tendinopathy were 83.9% and 74.5%, respectively. Positive predictive value was 66.7%. Negative predictive value was 88.4%. Accuracy rate was 78.0%.

CONCLUSIONS

MRI is a useful diagnostic tool for detecting peroneal tendinopathy in patients with chronic lateral ankle instability. However, MRI is vague in many cases. Therefore, a thorough delicate physical examination and careful observation is needed.

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.

Ankle: isotropic MR imaging with 3D-FSE-cube--initial experience in healthy volunteers

The purpose of this prospective study was to compare a new isotropic three-dimensional (3D) fast spin-echo (FSE) pulse sequence with parallel imaging and extended echo train acquisition (3D-FSE-Cube) with a conventional two-dimensional (2D) FSE sequence for magnetic resonance (MR) imaging of the ankle. After institutional review board approval and informed consent were obtained and in accordance with HIPAA privacy guidelines, MR imaging was performed in the ankles of 10 healthy volunteers (four men, six women; age range, 25-41 years). Imaging with the 3D-FSE-Cube sequence was performed at 3.0 T by using both one-dimensional- and 2D-accelerated autocalibrated parallel imaging to decrease imaging time. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) with 3D-FSE-Cube were compared with those of the standard 2D FSE sequence. Cartilage, muscle, and fluid SNRs were significantly higher with the 3D-FSE-Cube sequence (P < .01 for all). Fluid-cartilage CNR was similar for both techniques. The two sequences were also compared for overall image quality, blurring, and artifacts. No significant difference for overall image quality and artifacts was demonstrated between the 2D FSE and 3D-FSE-Cube sequences, although the section thickness in 3D-FSE-Cube imaging was much thinner (0.6 mm). However, blurring was significantly greater on the 3D-FSE-Cube images (P < .04). The 3D-FSE-Cube sequence with isotropic resolution is a promising new MR imaging sequence for viewing complex joint anatomy.

Arthroscopic and magnetic resonance image appearance and reconstruction of the anterior talofibular ligament in cases of apparent functional ankle instability

BACKGROUND

Many patients report feeling functional ankle instability, despite having no clinically demonstrable lateral instability.

HYPOTHESIS

Some patients who experience functional instability of the ankle have substantial abnormalities of the anterior talofibular ligament despite having apparently normal lateral laxity in clinical examination.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Fourteen patients who had functional ankle instability after sprain, despite having no clinically demonstrable lateral instability, were included in this study. All subjects underwent standard stress radiography, magnetic resonance imaging, and ankle arthroscopy. These patients were treated with anatomical reconstruction of the anterior talofibular ligament.

RESULTS

Arthroscopic assessment revealed 3 cases with no ligamentous structure with scar tissue, 9 cases with partial ligament tears and scar tissue on the disrupted anterior talofibular ligament fiber, and 2 cases of abnormal course of the ligament at the fibular or talar attachment. Magnetic resonance imaging revealed the following: 5 cases of discontinuity of the anterior talofibular ligament, 2 cases of narrowing of the anterior talofibular ligament, 4 cases of high-intensity lesion in the anterior talofibular ligament, and 3 normal cases. The mean American Orthopaedic Foot and Ankle Society Ankle Hindfoot scale score was 66.2 +/- 3.2 points at preoperation and 92.3 +/- 4.4 points 2 years after surgery.

CONCLUSION

All patients in this study with functional ankle instability, despite their having no demonstrable abnormal lateral laxity, had morphologic ligamentous abnormality on arthroscopic assessment.

Usefulness of ultrasonographic detection of talocrural effusion in ankle sprains

OBJECTIVE

Ankle sprain severity is difficult to assess initially in the emergency department, yet it governs treatment decisions. Ultrasonography readily shows fluid present in the talocrural joint, which is difficult to assess by physical examination. The purpose of this study was to evaluate the prevalence of ultrasonographic talocrural joint effusion in moderate and severe ankle sprains and to determine the cause of effusions by magnetic resonance imaging (MRI).

METHODS

Consecutive patients 18 to 55 years of age with moderate and severe ankle sprains within the previous 48 hours were included if they had no history of abnormalities in the same ankle within the last 12 months. When ultrasonography with the ankle in the neutral position showed talocrural effusion, MRI was performed within 8 days.

RESULTS

Of the 110 patients (83 men and 27 women; mean age, 24.2 years), 40 (36.4%; 95% confidence interval, 27.6%-46.1%) had joint effusion on ultrasonography and MRI. In 39 of these 40 patients, MRI visualized damage to the anterior talofibular ligament (positive predictive value, 97.5%; 95% confidence interval, 85.3%-99.9%), accompanied in 5 (12.8%) cases by damage to the calcaneofibular ligament. In 14 (35%) cases, MRI showed cartilage damage or bony contusion.

CONCLUSIONS

Talocrural effusion on ultrasonography may identify patients with severe ankle sprains. Magnetic resonance imaging should be performed in patients with talocrural effusion. Further work is needed to evaluate the usefulness of MRI in acute ankle sprains without talocrural effusion.

Arthroscopic assessment for intra-articular disorders in residual ankle disability after sprain

BACKGROUND

After ankle sprain, there can be many causes of disability, the origins of which cannot be determined using standard diagnostic tools.

HYPOTHESIS

Ankle arthroscopy is a useful tool in identifying intra-articular disorders of the talocrural joint in cases of residual ankle disability after sprain.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

The authors gathered the independent diagnostic results of physical examination, standard mortise and lateral radiography, stress radiography of the talocrural joint, and magnetic resonance imaging for 72 patients with residual ankle disability lasting more than 2 months after injury (mean, 7 months after injury). They performed arthroscopic procedures and compared the double-blind results.

RESULTS

In all cases, the arthroscopic results matched those of other means of diagnosis. In 14 cases, the arthroscopic approach exceeded the capabilities of the other methods. Including duplications, 39 patients (54.2%) had anterior talofibular ligament injuries, 17 patients (23.6%) had distal tibiofibular ligament injuries, 29 patients (40.3%) had osteochondral lesions, 13 patients (18%) had symptomatic os subfibulare, 3 patients (4.2%) had anterior impingement exostosis, and 3 patients (4.2%) had impingement due to abnormally fibrous bands. There were only 2 cases in which the cause of symptoms could not be detected by ankle arthroscopy, compared with 16 cases in which the cause of disability could not be detected using standard methods. In 3 cases (17.6%) of distal tibiofibular ligament injuries, 8 cases (27.6%) of osteochondral lesions, and all 3 cases (100%) of impingement of an abnormal fibrous band, ankle arthroscopy was the only method capable of diagnosing the cause of residual ankle pain after a sprain.

CONCLUSION

The present results suggest that arthroscopy can be used to diagnose the cause of residual pain after an ankle sprain in most cases that are otherwise undiagnosable by clinical examination and imaging study.

The medial longitudinal arch as a possible risk factor for ankle sprains: a prospective study in 83 female infantry recruits

BACKGROUND

Ankle sprains are frequent, especially in athletes, soldiers, or others who perform high levels of physical activity. Although prevention is a primary goal, little is known about the risk factors. We evaluated the association of the structure of the medial arch of the foot to the occurrence of acute and recurrent ankle sprains in 83 female infantry recruits. We found no previous studies on ankle sprains in women in the English literature.

METHODS

Arch height was quantified using the Chippaux-Smirak index, and each arch was classified as high, normal, or low. Retrospective data were obtained from questionnaires in which the soldiers noted whether or not they had had ankle sprains in the past, the grade of the sprain, and recurrence. Prospective data were accumulated in the 4 months of basic training, during which time every ankle sprain was documented and classified according to its grade and cause.

RESULTS

The retrospective data showed more frequent ankle sprains in the low arch group than in the normal arch group, mainly in the right foot (RR of 2.9, p <0.05). Recurrent sprains studied retrospectively also showed that more sprains occurred in the low arch group than in the normal arch and high arch groups (RR of 10.3, p <0.05). The prospective data suggested a pattern toward the same outcome (50% in the low arch as opposed to 36% in the normal arch group, RR, 1.3), but with no statistical significance.

CONCLUSIONS

We concluded that a low arch of the foot might be a risk factor for ankle sprains. However, our study consisted of a relatively small population, and further studies are needed.

Acute ankle injury and chronic lateral instability in the athlete

Ankle injuries occur frequently in sports. The lateral ligamentous complex, specifically the anterior talofibular and calcaneofibular ligaments, are most commonly injured. In acute lateral ligament injuries, a functional ankle rehabilitation program is the mainstay of treatment. Chronic ankle instability develops in a minority of patients. Surgical procedures are broadly classified into anatomic ligament repairs versus reconstructive tenodeses. Commonly performed techniques include the Brostrom-Gould procedure,the modified Brostrum-Evans procedure, and the Chrisman-Snook procedure.

MRI of sports-related injuries of the foot and ankle: part 1

The ankle is one of the most frequently injured joints in the course of sports activities. MR imaging has become the modality of choice in the evaluation of most of these lesions, especially in competitive athletes. The purpose of this article is: (1) To illustrate the MR imaging features of a great number of sports-related injuries of the ankle, correlating it with lesional mechanisms and clinical findings, and (2) To review the role of MR imaging in clinical management and surgical planning of these injuries, especially in competitive athletes. In order to a better understanding of these lesions, a classification based on the anatomic origin are outlined. The spectrum of injuries has been classified in: (1) osseous lesions, (2) ligamentous injuries, (3) tendinous lesions, (4) impingement impingement, and (5) plantar fascial lesions.

Sonography and MR imaging of posterior tibial tendinopathy

OBJECTIVE

The purpose of the study is to describe the appearance of the posterior tibialis tendon on MR imaging and high-resolution sonography with color and power Doppler imaging and to determine whether sonography is as accurate for diagnosing tendinosis as MR imaging.

SUBJECTS AND METHODS

Fifteen healthy volunteers and 31 patients (44 tendons) who were clinically suspected of having posterior tibial tendinopathy were prospectively evaluated with MR imaging and sonography.

RESULTS

On MR imaging, the normal tendon was elliptic on cross section and showed low signal intensity on all sequences. Minimal peritendinous enhancement and fluid were seen. On sonography, the tendon showed homogeneous longitudinal echogenic fibers. No flow was seen in or around the tendon. Tendinopathy was characterized by enhancement of the tendon on MR imaging (19/44 tendons); intratendinous flow on color Doppler sonography (16/44 tendons); increase in the anteroposterior diameter causing a rounding of the tendon (18/44 tendons); and inhomogeneity of the tendon (16/44 tendons on MR imaging and 21/44 tendons on sonography). Peritendinosis was characterized by peritendinous enhancement on MR imaging (29/44 tendons); flow on color Doppler sonography (20/44 tendons); and increased soft tissue (20/44 tendons on MR imaging and 27/44 tendons on sonography). When compared with MR imaging, the sensitivity and specificity of sonography for diagnosing tendinopathy were 80% and 90%, respectively, and for diagnosing peritendinosis were 90% and 80%. Addition of abnormal size to the structural abnormality criteria did not improve diagnostic ability.

CONCLUSION

Sonography can be useful as the initial imaging study in evaluating abnormalities caused by posterior tibial tendinopathy.

Comparison of acute swelling and function in subjects with lateral ankle injury

STUDY DESIGN

Prospective correlational study involving a convenience sample.

OBJECTIVES

To investigate the relationships among figure-of-eight girth measurements and functional level in patients with acute lateral ankle sprains to determine the appropriate use of these clinical measures.

BACKGROUND

Research has shown that subjective scales of perceived athletic ability and measurements of swelling are useful in assessing clinical improvement following an acute ankle sprain; however, the relationship between ankle swelling and level of function is not known.

METHODS AND MEASURES

Twenty-nine subjects (20 men, 9 women) varying in age from 18-59 years of age (mean age, 30.8 +/- 11.37) with acute lateral ankle sprains were included in this study. Each subject was evaluated by 1 of 3 raters for ankle girth, weight-bearing status, and functional level as determined by a modified Ankle Osteoarthritis Scale (AOS) and the Foot and Ankle Ability Index (FAAI). This study also investigated the relationship between these measures and the sport subscale of the FAAI (FAAI sport). This is an 8-item subscale which includes questions on running, jumping, landing, quick starts and stops, cutting or lateral movements, low impact activities, ability to perform an activity with normal technique, and ability to participate in desired sports.

RESULTS

No significant correlations were found between figure-of-eight girth measurements and functional level. However, we did find moderate to good correlations between the FAAI vs. weight-bearing (rho = 0.73), FAAI vs. AOS (rho = -0.79), FAAI sport vs. weight-bearing (rho = 0.68), FAAI vs. FAAI Sport (rho = 0.73), weight-bearing vs. AOS (rho = -0.57), and FAAI Sport vs. AOS (rho = -0.50).

CONCLUSIONS

The figure-of-eight method is highly reliable and is appropriate for measuring ankle swelling; however, it does not correlate with functional level as determined by the modified AOS, FAAI, or observed weight-bearing status during gait. Therefore, clinicians should refrain from making assumptions about function based on ankle swelling.

Associated injuries found in chronic lateral ankle instability

Sixty-one patients underwent a primary ankle lateral ligament reconstruction for chronic instability between 1989 and 1996. In addition to the ligament reconstruction, all patients had evaluation of the peroneal retinaculum, peroneal tendon inspection by routine opening of the tendon sheath, and ankle joint inspection by arthrotomy. A retrospective review of the clinical history, physical exam, MRI examination, and intraoperative findings was conducted on these 61 patients. The purpose was to determine the type and frequency of associated injuries found at surgery and during the preoperative evaluation. At surgery no patients were found to have isolated lateral ligament injury. Fifteen different associated injuries were noted. The injuries found most often by direct inspection included: peroneal tenosynovitis, 47/61 patients (77%); anterolateral impingement lesion, 41/61 (67%); attenuated peroneal retinaculum, 33/61 (54%); and ankle synovitis, 30/61 (49%). Other less common but significant associated injuries included: intra-articular loose body, 16/61 (26%); peroneus brevis tear, 15/61 (25%); talus osteochondral lesion, 14/61 (23%); medial ankle tendon tenosynovitis, 3/61 (5%). The findings of this study indicate there is a high frequency of associated injuries in patients with chronic lateral ankle instability. Peroneal tendon and retinacular pathology, as well as anterolateral impingement lesions, occur most often. A high index of suspicion for possible associated injuries may result in more consistent outcomes with nonoperative and operative treatment of patients with chronic lateral ankle instability.

Acute inversion injury of the ankle: magnetic resonance imaging and clinical outcomes

This study was undertaken to compare the clinical and magnetic resonance imaging results of 24 patients who had sustained ligament injuries after acute inversion injury of the ankle. On magnetic resonance imaging, the following lesions were detected: anterior talofibular ligament tear in 23 patients, calcaneofibular ligament lesion in 15, posterior talofibular ligament lesion in 11, interosseous talocalcaneal ligament lesion in 13, cervical ligament lesion in 12, and deltoid ligament lesion in 8. Compared with the clinical outcome at the follow-up study, there was a statistically significant relationship between interosseous talocalcaneal ligament lesion and each of giving way, pain, and limitation of ankle motion; between cervical ligament lesion and both giving way and pain; and between deltoid ligament lesion and giving way (P < 0.05).

Occult osseous injuries after ankle sprains: incidence, location, pattern, and age

We retrospectively evaluated 109 magnetic resonance studies in patients with prior ankle sprains to investigate the frequency and pattern of bone bruises. Patterns of bone bruises were then correlated with the ligaments injured. In addition, the age of the injury was determined from medical records to correlate the presence of bone bruises with the temporal period from injury. Bone bruises occurred in 39% of ankle sprains. Multiple bone bruises were seen in 40% of those with bone bruises; they occurred more frequently in patients with multiple ligaments injured. The marrow changes may be secondary to impaction, rotary instability of the ankle, and microavulsion vectors. Bone bruise-like lesions were seen at an average of 8.4 weeks in age but were seen more than a year after the injury. We conclude that bone bruises frequently occur in patients with ankle sprains, and the marrow changes may be caused by one of the three proposed mechanisms.