Diagnostic tools to evaluate ankle instability caused by a deltoid ligament rupture in patients with supination-external rotation ankle fractures: A systematic review and meta-analysis

AIM

Supination-external rotation (SER) ankle fractures account for the majority of ankle fractures and can be divided into stable or unstable fractures, based on the state of the deltoid ligament. The objective of this review was to appraise the available literature concerning diagnostic tools to evaluate deltoid ligament integrity in patients with SER-type ankle fractures.

METHODS

A comprehensive literature search of Pubmed and Embase was performed up to December 2020. The outcome measures were sensitivity, specificity and positive and negative predictive value of the diagnostic tools. A meta-analysis was performed to obtain an overview of sensitivity, specificity and area under the curve (AUC). The methodological quality of the articles was evaluated using Quality Assessment of Diagnostic Accuracy Studies.

RESULTS

A total of 12 studies investigating tools for deltoid ligament rupture in patients with SER-type ankle fractures were included. The present study found sensitivity (and specificity) ranges of 0.20-0.90 (and 0.38-0.97) for clinical features, Magnetic Resonance Imaging (MRI) 0.57-0.85 (and 0.81-1.00), ultrasonography 1.00 (and 0.89-1.00), Malleolar Medial Fleck Sign (MMFS) 0.25 (and 0.99), conventional ankle mortise radiography 0.33-0.57 (and 0.60-0.94), gravity stress radiography 0.71-1.00 (and 0.72-0.88) and manual stress ankle radiography 0.65-1.00 (and 0.00-0.77). The largest AUC was found for ultrasonography, followed by MMFS, gravity stress radiography and MRI.

CONCLUSION

Ultrasonography and gravity stress radiography seem the most accurate diagnostic tools to evaluate deltoid ligament integrity. To strengthen this conclusion, future research should use an identical reference test to ensure comparability of results. Nevertheless, present study is of high value to close the knowledge gap about which presently available diagnostic tool is to be preferred to evaluate deltoid ligament integrity in patients with SER-type ankle fractures.

Anthropometric measurements can identify small for gestational age newborns: a cohort study in rural Tanzania

Background

Small-for-gestational-age (SGA) is associated with increased neonatal mortality and morbidity. In low and middle income countries an accurate gestational age is often not known, making the identification of SGA newborns difficult. Measuring foot length, chest circumference and mid upper arm circumference (MUAC) of the newborn have previously been shown to be reasonable methods for detecting low birth weight (< 2500 g) and prematurity (gestational age <  37 weeks). The aim of this study was to investigate if the three anthropometric measurements could also correctly identify SGA newborns.

Methods

In the current study from a rural area of northeastern Tanzania, 376 live newborns had foot length, chest circumference, and MUAC measured within 24 h of birth. Gestational age was estimated by transabdominal ultrasound in early pregnancy and SGA was diagnosed using a sex-specific weight reference chart previously developed in the study area. Receiver operating characteristic curves were generated for each of the anthropometric measurements and the area under the curve (AUC) compared. Operational cutoffs for foot length, chest circumference, and MUAC were defined while balancing as high as possible sensitivity and specificity for identifying SGA. Positive and negative predictive values (PPV and NPV) were then calculated.

Results

Of the 376 newborns, 68 (18.4%) were SGA. The AUC for detecting SGA was 0.78 for foot length, 0.88 for chest circumference, and 0.85 for MUAC. Operational cut-offs to detect SGA newborns were defined as ≤7.7 cm for foot length, ≤31.6 cm for chest circumference and ≤ 10.1 cm for MUAC. Foot length had 74% sensitivity, 69% specificity, PPV of 0.35 and NPV of 0.92 for identifying SGA. Chest circumference had 79% sensitivity, 81% specificity, PPV of 0.49 and NPV of 0.95 for identifying SGA. Finally, MUAC had 76% sensitivity, 77% specificity, PPV of 0.43 and NPV of 0.94 for identifying SGA.

Conclusion

In a setting with limited availability of an accurate gestational age, all three methods had a high NPV and could be used to rule out the newborn as being SGA. Overall, chest circumference was the best method to identify SGA newborns, whereas foot length and MUAC had lower detection ability.

Trial registration

Clinicaltrials.gov (NCT02191683). Registered 2 July 2014.

Electronic supplementary material

The online version of this article (10.1186/s12887-019-1500-0) contains supplementary material, which is available to authorized users.

Treadmill stress tests should not be part of "routine health check package"

A treadmill ECG stress test (TMT) often forms part of the popular health check packages recommended for people who are asymptomatic on the premise that it can detect disease at an early stage and treatment be prescribed to prevent or reduce future morbidity and mortality. Such a recommendation does not take into account the properties of this procedure as a diagnostic test. It has an average sensitivity and specificity of 68% and 77%, respectively. However, these figures depend on the probability of coronary artery disease (CAD) in the test subject. In asymptomatic persons with few or no risk factors, the likelihood of a false positive is high and will result in psychological stress and/or expensive and possibly invasive test. Recommendation for a TMT should be made by a physician after evaluating the subject to have at least an intermediate risk of having CAD.