Acromion Index in Korean Population and Its Relationship with Rotator Cuff Tears

Abstract

BackgroundAmong the many causes of rotator cuff tears, scapular morphology is associated with the accelerating degenerative process of the rotator cuff. Acromion index (AI) was previously introduced and compared in two populations.MethodsWe enrolled 100 Korean patients diagnosed with full-thickness rotator cuff tears by magnetic resonance imaging and intraoperative arthroscopic findings between January and December 2013. Another 100 Korean patients with an intact rotator cuff tendon identified on magnetic resonance imaging and other shoulder diseases, such as frozen shoulder and instability, were enrolled as controls. We retrospectively compared these 100 rotator cuff tear patients (mean age, 63 years) and 100 controls (mean age, 51 years) in this study. Two independent orthopedic surgeons assessed the AI on radiographs. We performed an interobserver reliability test of the AI assessment, and then compared the AI between two groups.ResultsThe measurement of the AI showed excellent reliability (intraclass correlation coefficient, 0.82). The mean AI in the rotator cuff tear group was 0.68 and it was significantly different between groups (p<0.001, 95% confidence interval). The AI was not related to tear size.ConclusionsOur study showed that the AI was an effective predictive factor for rotator cuff tears in a Korean population.

Acromion morphology and prevalence of rotator cuff tear: A systematic review and meta‐analysis

“…The usefulness of the cut‐off value by itself as a predictor of RTC tears is only fair because the area under the ROC curve was 0.75. However, our cutoff value of 0.695 is similar to the cut‐off values reported by Kum et al () of 0.66 and Moor et al () of 0.68.…”

“…The usefulness of the cut-off value by itself as a predictor of RTC tears is only fair because the area under the ROC curve was 0.75. However, our cutoff value of 0.695 is similar to the cut-off values reported by Kum et al (2017) This greater prevalence of RTC tears in persons with higher acromial index may be due to an alteration in the force vector of the deltoid muscle causing an increased superiorly directed force of the humeral head into the acromion and coracoacromial arch (Nyffeler et al, 2006). The change in the deltoid force vector in turn might affect the ability of the stabilizing RTC muscles to compress and stabilize the humeral head in the glenoid with shoulder elevation.…”

“…Acromion type data were extracted in the form of count data. Acromial index data were extracted in the form of means, standard deviations, and sample sizes, except for one study which used means, sample sizes, and an independent t ‐test P ‐value (Kum et al, ). Because all of the included studies were observational in nature, we assessed study quality using the Quality Assessment Tool for Quantitative Studies (Thomas et al, ); this was done independently by two of the present study's authors.…”

Correlation between acromiohumeral distance and the severity of supraspinatus tendon tear by ultrasound imaging in a Chinese population

“…Previously, AHD has been studied in literature mainly through standard X-ray of the shoulder [9,10]. However, the reliability of radiological AHD measurement has not been supported by a review of studies to date [4].…”

“…It is therefore essential that a reliable method of AHD measurement is identified [4]. Previously, AHD has been studied through a standard X-ray of the shoulder [9,10]. However, radiographic AHD measurement is problematic as it is affected by both the patient's position and X-ray beam direction [11].…”