Synovial chondromatosis is a benign condition characterized by synovial proliferation and metaplasia, with development of cartilaginous or osteocartilaginous nodules within a joint, bursa or tendon sheath. In the shoulder, synovial osteochondromatosis may occur within the glenohumeral joint and its recesses (including the tendon sheath of the biceps long head), and in the subacromial-deltoid bursa. Such condition can be identified either by radiography, ultrasonography or magnetic resonance imaging, showing typical features according to each method. Radiography commonly shows ring-shaped calcified cartilages and periarticular soft tissues swelling with erosion of joint margins. Ultrasonography demonstrates hypoechogenic cartilaginous nodules with progressive increase in echogenicity as they become calcified, with development of posterior acoustic shadow in case of ossification. Besides identifying cartilaginous nodules, magnetic resonance imaging can also demonstrate the degree of synovial proliferation. The present study is aimed at describing the imaging findings of this entity in the shoulder.

Keywords: Synovial chondromatosis; Image findings; Shoulder.

OBJECTIVE: To identify the computed tomography findings suggestive of intestinal perforation by an ingested foreign body. MATERIALS AND METHODS: This was a retrospective study of four cases of surgically proven intestinal perforation by a foreign body, comparing the computed tomography findings with those described in the literature. RESULTS: None of the patients reported having ingested a foreign body, all were over 60 years of age, three of the four patients used a dental prosthesis, and all of the foreign bodies were elongated and sharp. In all four patients, there were findings indicative of acute abdomen. None of the foreign bodies were identified on conventional X-rays. The computed tomography findings suggestive of perforation were thickening of the intestinal walls (in all four cases), increased density of mesenteric fat (in all four cases), identification of the foreign body passing through the intestinal wall (in three cases), and gas in the peritoneal cavity (in one case). CONCLUSION: In cases of foreign body ingestion, intestinal perforation is more common when the foreign body is elongated and sharp. Although patients typically do not report having ingested such foreign bodies, the scenario should be suspected in elderly individuals who use dental prostheses. A computed tomography scan can detect foreign bodies, locate perforations, and guide treatment. The findings that suggest perforation are thickening of the intestinal walls, increased mesenteric fat density, and, less frequently, gas in the peritoneal cavity, often restricted to the point of perforation.

Keywords: Intestinal perforation; Intestine, small; Foreign bodies; Abdomen, acute; Tomography, X-ray computed.

OBJECTIVE: To evaluate the effect of acromial inferolateral tilt on subacromial impingement syndrome. MATERIALS AND METHODS: The acromial inferolateral tilt was retrospectively quantified by two researchers on 346 shoulder magnetic resonance images using the glenoacromial (between the inferior proximal acromial surface and the glenoidal face) and acromioclavicular (between the axis of the proximal acromion and distal clavicle) angles. RESULTS: The glenoacromial angle was associated with subacromial impingement syndrome (p < 0.001) and complete supraspinatus tendon rupture (p < 0.001), and the acromioclavicular angle was associated with partial or complete supraspinatus tendon rupture (p = 0.003). The area under the receiver operating characteristic curve (AUC), best cut-off angle, and odds ratio (OR) of the glenoacromial angle for impingement syndrome were 0.579 (95% confidence interval [CI]: 0.508–0.649; p = 0.032), 72°, and 2.1 (95% CI: 1.136–4.053), respectively. For complete supraspinatus tendon rupture, the AUC, best cut-off angle, and OR of the glenoacromial angle were 0.731 (95% CI: 0.626–0.837; p = 0.001), 69°, and 8.496 (95% CI: 2.883–28.33), respectively. For partial or complete supraspinatus tendon rupture, the AUC, best cut-off angle and OR of the acromioclavicular angle were 0.617 (95% CI: 0.539–0.694; p = 0.002), 17°, and 3.288 (95% CI: 1.886–5.768), respectively. Interobserver agreement found for the glenoacromial and acromioclavicular angles were 0.737 (95% CI: 0.676–0.787; p < 0.001) and 0.507 (95% CI: 0.391–0.601; p = 0.001), respectively. CONCLUSION: Inferolateral acromial tilt may have some impact on subacromial impingement syndrome; however, the best quantification method identified (glenoacromial angle) showed a moderate interobserver agreement and a fair performance to assess the risk of complete supraspinatus tendon rupture.

Keywords: Shoulder impingement syndrome; Inferolateral acromial tilt; Magnetic resonance imaging.