Radiographic measurement of prevertebral soft tissue thickness on lateral radiographs of the neck.

PURPOSE: The prevertebral soft tissue measurement is commonly used for assessing prevertebral pathology such as abscesses or hematomas after injury. Very few references concerning the ratio of retrotracheal thickness to C5 diameter are available in the literature. The purpose of this study was to measure the normal soft tissue thickness at the C5 level of the neck and to establish the normal ratio of retrotracheal soft tissue thickness to the diameter of C5 for daily use. DESIGN AND PATIENTS: We measured soft tissue thickness in the neck of 54 normal subjects and calculated the mean and standard deviation. RESULTS AND CONCLUSION: Using mean plus one standard deviation the maximum retrocricoid soft tissue thickness was 0.7xC5 diameter and maximum retrotracheal thickness was 1.0xC5 diameter. Soft tissue thickness that exceeds this limit must be studied further for signs of potential disease.

Abnormal calcification on plain radiographs of the abdomen.

The purpose of this pictorial review is to facilitate recognition and understanding of calcifications seen on conventional radiographs of the abdomen. Calcifications can be categorized by organ system and location in the abdomen. Both common and rare calcifications in the urinary tract, liver, gallbladder, spleen, pancreas, adrenal glands, digestive tract, genital tract, peritoneal cavity, and retroperitoneum are illustrated. Abnormal calcifications in the urinary tract are subcategorized by kidneys, ureters, bladder, and urethra. The density, shape, size, margins, pattern, position, and mobility of calcifications are emphasized for differential diagnoses.

Boehler's angle: a reappraisal.

STUDY OBJECTIVES: To reappraise Boehler's angle and evaluate factors, including centering of the central beam, sex of subjects, and side of the body, that may affect angle measurement. DESIGN: Retrospective clinical review. SETTING: Emergency department, Level I trauma center. TYPE OF PARTICIPANTS: 120 consecutive patients radiographed for ankle injury who had normal bones on the ankle and/or foot radiographs. MEASUREMENTS AND MAIN RESULTS: The mean and SD of Boehler's angle were 30 degrees C +/- 6 degrees (range, 14 degrees to 50 degrees). There was no difference in Boehler's angle between male and female subjects (P greater than .05) or between left and right feet (P greater than .05). Slight variations in central beam location for ankle and foot radiographs had no significant effect on Boehler's angle. CONCLUSION: If 28 degrees is taken as the lower limit of normal for Boehler's angle, 37 cases (31%) would be false-positive "abnormal." The use of 20 degrees as the lower limit may decrease the number of false-positive to three cases (2.5%); using 18 degrees (mean -2 SD) reduces the false-positive rate to less than 1% (one case).

Cervical spine flexion patterns.

Lateral projection flexion and extension radiographs of the cervical spine are stress views. They are necessary to evaluate unstable ligamentous injury, which may not be apparent on neutral unstressed films. As there is very little literature on the proper evaluation of these radiographic views, we reviewed 150 consecutive cases from our Emergency Department to define patterns of flexion. Four significantly different patterns emerged. No flexion at any level was seen in 24.7% of patients. A single flexion angle was seen in 24.7% Two flexion angles, usually at consecutive levels, were present in 29.3% of patients, and 21.3% had three or more flexion angles. Correlation with clinical data suggests that attempted flexion with no significant angle or a single angle is abnormal and may indicate soft tissue (ligament or muscle) injury. Three or more flexion angles are thought to represent a normal pattern. The most common pattern, two flexion angles at consecutive levels, has not been previously described. We believe this pattern indicates less than full flexion and can be seen in individuals without significant injury and in those limited by mild soft-tissue injury.

Coracoclavicular and coracoacromial ligament calcification and ossification.

Thirty-six patients with calcification or ossification at or around the coracoclavicular and coracoacromial regions were analyzed with regard to type, location, and configuration of the deposits and related clinical history. Calcification or ossification in the coracoclavicular region resulted largely from trauma (36%) or renal failure (28%). Trauma patients may develop punctate calcification or ossification but do not develop the tumoral type of calcification. About 5% of the renal failure patients had coracoclavicular ligament calcifications, one-half of which were of the tumoral type. Renal failure patients may have punctate or tumoral calcifications but do not develop ossification.

Cervical spine annulus vacuum.

Thirty-eight annulus vacuums in 27 patients were analyzed with regard to location, configuration, and associated vertebral abnormalities such as degenerative changes, absent and compressed anterosuperior vertebral body corners, and annulus calcification. It is concluded that most annulus vacuums are a degenerative phenomenon at the attachment of the annulus to bone. These vacuums may be associated with other degenerative changes such as osteophytes and annulus calcification. Vacuums have a strong association with compressed anterosuperior corners. These deformed corners are thought to be early osteophytes and may be related to previous trauma, a vertebra with an absent corner, and/or normal motion. Small annulus vacuums adjacent to vertebral corners with a normal appearance are more likely to result from acute trauma.

Some upper cervical spine norms.

Lateral cervical spine films from 175 normal examinations of adults performed in the emergency room of North Carolina Baptist Hospital were analyzed to establish some norms and relationships in the upper cervical spine. The predens angle was found to be between 0 degree-13 degrees (mean 5.57 degrees) in neutral position and 0-18 degrees (mean 9.27 degrees) in flexion in most persons. Ninety-two percent of persons have angles greater than 3 degrees in flexion. A V-shaped predens space is not indicative of injury to the cruciate ligament. Virtually every person has posterior slanting or tilting of the dens and the range of values is up to 35 degrees (mean 17.43 degrees). Ninety-eight percent of persons have an angle greater than 6 degrees. A tilted dens does not indicate acute or remote trauma. No relationship was identified between the predens angle and the dens tilt angle. The posterior arch of the atlas can be found at any position between the occiput and spinous process of C2 in all positions of the head and neck. Hence, fanning or widening of the C1-C2 interspinous distance is not a reliable index of ligamentous injury in the upper cervical spine.