Bizarre parosteal osteochondromatous proliferation: Nora's lesion

The purpose of this study was to review the imaging and anatomopathologic findings and to discuss the main differential diagnosis of bizarre parosteal osteochondromatous proliferation [BPOP] or Nora's lesion, a rare benign surface lesion of the bone. Histologically confirmed plain radiographs, ultrasound, CT and MRI images of four patients with BPOP were obtained and retrospectively reviewed. Three cases involving the hand and one involving the foot are reported. On plain radiographs, BPOP is a well-marginated, calcified or ossified mass arising directly from the cortical surface of the underlying bone. Ultrasound images show a low echoic peripheral cap around the lesion. CT images show the wide base of the lesion. On MRI, BPOP was of a low signal on T1, enhancing following gadolinium administration. Underlying bone and adjacent surrounding soft tissues were normal

Diagnostic accuracy of high resolution ultrasound in communicating rotator cuff tears

High resolution ultrasound is performed in the investigation of rotator cuff pathology. However, there are various reports in the literature regarding the diagnostic accuracy of ultrasound. The purpose of our study was to compare the diagnostic accuracy of ultrasound with multislice computed tomography arthrography [CT arthrography]. We prospectively studied sixty-four consecutive patients with rotator cuff pathology diagnosed by ultrasound [35 men and 29 women; age range, 35-75] who underwent preoperative multislice CT arthrography of the shoulder from February 2006 to January 2008. Full-thickness and communicating partial-thickness tears of the supraspinatus, infraspinatus, subscapularis tendons as well as the abnormalities of the long head of the biceps tendon were assessed. The right shoulder was involved in 44 patients. The supraspinatus tendon was the most frequently involved either by full-thickness [n=50] or partial-thickness [n=29] tears. Ultrasound correctly identified full-thickness rotator cuff tears in 84% of cases with a good positive predictive value [83%]. The sensitivity and specificity of ultrasound in the detection of partial-thickness tears were 76% and 46%, respectively. These percentages significantly increased with the presence of joint effusion [77% vs 70%] and joint and subacromial/subdeltoid bursal effusion [80% vs 67%]. Ultrasound allows an accurate diagnosis of full-thickness tears. The diagnostic performance of ultrasound in the assessment of partial-thickness tears increases when a joint effusion or double effusion is present