Abstract
Shoulder pain or loss of normal range of motion is a frequent complaint in the outpatient clinic. Of these presentations, rotator cuff injury is a common cause. This can range from mild, transient inflammation of the tendons, to partial tears of tendons, or even full thickness tears. Disruption of the tendons can occur from forceful forward throwing actions undertaken in some sports, for example baseball pitching, more commonly in the UK however, chronic impingement can lead eventually to a tendon tear-usually seen in an older population. Current methods of investigation of such injuries after clinical history and examination, includes plain film radiography, ultrasonography, magnetic resonance imaging and arthrography. We decided to look at how ultrasound can be used in the district general hospital for investigation of such injuries.
Aims
To determine the accuracy of ultrasound as an investigative tool for clinically suspected rotator cuff tears.
Methods
Seventy-five consecutive ultrasonographic study reports, in patients who subsequently underwent arthroscopic examination, were scrutinised and correlated with surgical findings. From this, sensitivity and specificity of ultrasound at this district general hospital were calculated. In addition, this data was compiled for each of the three Consultant Radiologists in order to assess the operator dependent nature of ultrasound.
Results
Of the 74 cases analysed, 43 (58.1%) had full correlation with the arthroscopy findings, 13 (17.6%) had mixed correlation, and 18 cases (24.3%) had no correlation between the ultrasound and arthroscopy report. The sensitivity and specificity of ultrasound at our institution was 0.76 and 0.8 respectively with regards to a tear being detected at ultrasound and then visualised during surgery.
Conclusions
There is no current national guidance as to which imaging modality should be first line following clinical examination. Magnetic resonance arthrography, widely thought of as being the gold standard investigation, is not only expensive and possible only in certain centres, but is also invasive, time consuming, and has many relative contraindications. Ultrasound offers a clinical advantage by allowing the radiologist to speak to the patient and assess their range of motion whilst performing the study. This interaction is lost totally in MRI, CT and even MR arthrography. Our study shows that ultrasonography can be quite accurate in identifying a rotator cuff tear. Although it is operator-dependent, ultrasound should be considered more often as a first-line imaging tool for suspected rotator cuff tears as it is relatively inexpensive, quick, and most importantly dynamic.