Quantitative analysis with load–displacement ratio measured via digital arthrometer in the diagnostic evaluation of chronic ankle instability: a cross-sectional study

Abstract

Background Arthrometry has been introduced to evaluate the laxity of ankle joint in recent years. However, its role in the diagnosis of chronic ankle instability is still debatable. Therefore, we assessed the diagnostic accuracy of a digital arthrometer in terms of sensitivity and specificity. Methods According to the inclusion and exclusion criteria proposed by the International Ankle Consortium, we recruited 160 uninjured ankles (control group) and 153 ankles with chronic ankle instability (CAI group). Ankle laxity was quantitively measured by a validated digital arthrometer. Data of loading force and joint displacement were recorded in a continuous manner. Differences between the control and CAI groups were compared using 2-tailed independent t test. A receiver operating characteristic curve analysis was used to calculate area under a curve, sensitivity and specificity. Results Load–displacement curves of the two groups were depicted. Differences of joint displacement between the control and CAI groups were compared at 30, 45, 60, 75, 90, 105 and 120 N, which were all of statistical significance (all p < 0.001) with the largest effect size at 90 N. Statistical significance was found in the differences between the two groups in load–displacement ratio at 10–120 N, 10–40 N, 40–80 N and 80–120 N (all p < 0.001), with the largest effect size at 10–40 N. Load–displacement ratio at the interval of 10–40 N had the highest area under a curve (0.9226), with sensitivity and specificity of 0.804 and 0.863, respectively, when the cutoff point was 0.1582 mm/N. Conclusion The digital arthrometer measurement could quantitively analyze the ankle laxity with high diagnostic accuracy. The load–displacement ratio would be a reliable and promising approach for chronic ankle instability diagnosis. Level of evidence level II.

A novel digital arthrometer to measure anterior tibial translation

“…Furthermore, the results of the Ligs test are quantitative indicators that can reduce experiential dependence. The Ligs device was also used by Chen et al for the assessment of chronic ankle instability and was found to have excellent intra- and interrater reliability with ICCs of 0.963 and 0.949, respectively [ 6 ]. Our study focused on testing knee laxity, a component whose potential has not been reported.…”

“…1 B). Chen et al used the Ligs device to quantify anterior drawer testing (ADT) in chronic ankle instability with satisfactory results [ 6 ]. However, the feasibility of quantifying ATT using this device has not yet been analyzed.…”

A novel digital arthrometer to measure anterior tibial translation: A Quantitative Study

“…Furthermore, the results of the Ligs test are quantitative indicators that can reduce experiential dependence. The Ligs device was also used by Chen et al for the assessment of chronic ankle instability and was found to have excellent intra-and interrater reliability with ICCs of 0.963 and 0.949, respectively (Chen et al, 2022). Moreover, there are currently no reports evaluating knee laxity detected by Ligs.…”

“…1B). Chen et al used the Ligs device to quantify anterior drawer testing (ADT) in chronic ankle instability with satisfactory results (Chen et al, 2022). However, the feasibility of quantifying ATT using this device has not yet been analyzed.…”

Multiplanar knee kinematics-based test battery helpfully guide return-to-sports decision-making after anterior cruciate ligament reconstruction

“…Knee laxity was evaluated using a Ligs Digital Arthrometer (Innomotion Inc, Shanghai, China), which was proved with excellent reliability (Chen et al, 2022). The patients placed the knee joint under the direction of the tester.…”