Predictors of rotator cuff tear on plain radiographs

V Garg, S Muthian, R Moverley, R Hartley

University Hospitals Dorset

To determine if rotator cuff tears can be predicted using radiological indices calculated from plain radiographs.

Our study was retrospective, and data was collected from computerized patient records. Eighty-nine patients who underwent surgery for symptomatic rotator cuff tear were selected and their notes and plain radiographs were analysed. The following indices were calculated from the plain anteroposterior radiographs of the shoulder: acromial index, critical shoulder angle, greater tuberosity angle and acromiohumeral distance.

There were 54 males and 45 females, and the average age was 62.39 years (range 34-79 yrs.). The average value for acromial index (AI) was 0.69, the average value for critical shoulder angle (CSA) was 37.58 degrees, the average greater tuberosity angle (GTA) was 72.88 degrees and the average acromiohumeral distance (AHD) was 7.52mm. Two (2) patients had all markers positive within predictive range for rotator cuff tear. Thirty-four (34) patients (38.20%) had three predictors positive. The most valid radiographic marker was acromial index (AI) as 77(86.51%) patients has measurements within reference range.

In symptomatic patients, the acromial index calculated on plain radiographs is the most sensitive predictor of the presence of a rotator cuff tear.