Exclusion of cervical spine instability in patients with blunt trauma with normal multidetector CT (MDCT) and radiography.

The objective of the study was to determine if negative multidetector computed tomography (MDCT) and lateral radiography of the cervical spine effectively excludes patients with unstable cervical spine injuries. Over a period of 40 months, 6558 people were admitted to our trauma service with blunt injury and 447 (6.8%) were found to have cervical fractures. Fractures were identified by CT and/or lateral radiography. In order to rule out clinically significant instability in the absence of fracture, we identified nine patients who required any type of stabilization of the cervical spine including anterior fusion, posterior fusion and external orthosis. These patients also underwent MR of the cervical spine. Radiography, CT, and MR images and reports of these nine patients were reviewed. Nine patients without a fracture required cervical stabilization. These patients had the following abnormalities: disc herniation with canal stenosis in three, unilateral jumped facet in three, and various other soft tissue abnormalities in three, all of which were evident on CT or radiography. All nine patients had evidence for cervical spine injury or instability by MDCT. Normal MDCT and radiography appears adequate to 'clear' the cervical spine. We recommend that patients requiring cervical spine clearance undergo a complete MDCT and lateral radiograph of the cervical spine. If these studies are entirely normal, then the cervical spine may be cleared. If any abnormalities, including disc herniation, soft tissue swelling and bony malalignments are noted by radiography and/or MDCT, further studies, including MR, are indicated prior to clearance of the cervical spine.

The stimulatory and inhibitory function of theophylline on amino acid-induced insulin release: studies with the perfused rat pancreas.

The effects of 5 mM theophylline on L-phenylalanine, L-alanine, and L-leucine-induced insulin secretion were studied using the isolated perfused rat pancreas, varying the sequence of the stimuli. Theophylline in the absence or presence of 3 mM D-glucose caused a small amount of insulin release with a slow onset and a slight and steady increase. Theophylline had no effect on phenylalanine (5, 10, or 20 mM)-induced insulin release independent of the sequence of stimuli. Alanine (20 mM), in the absence of glucose, had no significant insulin stimulatory action. When theophylline was added during the alanine perfusion only a small insulin release, comparable to that given by theophylline alone, could be observed. However, superimposing alanine on a theophylline perfusion led to a potentiation of insulin release. The leucine-induced insulin secretion was significantly altered by the addition of theophylline. At a low concentration of leucine (5 mM) theophylline caused potentiation of leucine-induced insulin secretion. At 10 and 20 mM leucine, theophylline led to a rapid concentration-dependent inhibitory period, followed by a potentiation in the case of 10 mM leucine, and by a restoration of the secretion rate at 20 mM leucine which did not exceed the secretion rate of 20 mM leucine alone. Subsequent removal of theophylline caused a marked "off effect." When 5 or 20 mM leucine was superimposed on a theophylline perfusion, a marked dose-dependent potentiation of the biphasic leucine-induced insulin release and no inhibitory phase could be observed. From these data it must be concluded that the effect of theophylline on the insulin secretory reposure of the beta cell to theophylline and the stimulus. Possible explanations for these phenomena are discussed.

Splenic abscess.

Fourteen cases of splenic abscess are reported and 159 cases previously cited in the literature are reviewed. The incidence, predisposing factors, pathogenesis, clinical features, bacteriology and radiologic findings are discussed. Infective endocarditis was the most common single antecedent infection. Hemoglobinopathies, non-penetrating abdominal trauma, and gastrointestinal malignancy appear to predispose the spleen to abscess formation. Emphasis is placed on clinical features and radiologic findings to aid practitioners in diagnosing this uncommon but often fatal infection. Also emphasized is the necessity for prompt surgical intervention when splenic abscess is suspected. An approach to the antimicrobial therapy in different clinical settings is outlined.

Ankle trauma.

Fractures and dislocations about the ankle joint are common injuries. The radiographic findings produced by these injuries are type-specific--that is, directly related to the mechanism that produced the injury. It is important for radiologists to recognize all of the aspects of a particular injury and to communicate this information to the orthopedic surgeon because treatment is predicated upon recognition of all the components of the injury. Treatment also depends upon restoration of anatomic contour to the articular surface of the ankle joint as well as to reestablishment of stability. Plain films, polydirectional tomography, CT, and MR imaging are useful for evaluating these abnormalities.

Trauma oblique radiographs of the knee.

Special trauma oblique radiographs of the knee were designed for the purpose of demonstrating the patella radiographically in a manner that would free it from the shadow of the distal end of the femur. These radiographs are made by directing the x-ray tube at an angle of 45 degrees and making two exposures, with the film placed first on the lateral and then on the medial side of the injured knee. These two radiographs have been found to be useful for delineating the extent of fractures of the patella as well as abnormalities of the tibial plateau.

Lumbar lordosis measurement. A new method versus Cobb technique.

STUDY DESIGN: A historic cross-sectional study of lumbar lordosis in 199 healthy individuals aged 1-30 years. OBJECTIVE: To evaluate the magnitude and rate of the development of the normal lumbar lordotic curve with age using two methods of measurement. SUMMARY OF BACKGROUND DATA: There is no agreement among spine physicians on the range of the normal lumbar lordotic curve. In certain conditions, such as a tethered spinal cord, a change in lordotic curve may indicate or even precede the onset of neurologic symptoms. Reliable measurements of the lumbar lordotic curve may aid in the early diagnosis and management of these conditions, before irreversible neurologic change ensues. METHODS: The lumbar lordotic curve was measured by the traditional Cobb technique and by a newly designed method, tangential radiologic assessment of lumbar lordosis. The data were subjected to the Morgan-Pitman test for correlated variances to observe which of the two methods was more reliable in measuring the magnitude and rate of change in the lumbar lordotic curve. RESULTS AND CONCLUSIONS: The rate of development of the lumbar lordotic curve appears to be nonlinear, increases during first year of life and during puberty, and reaches a plateau of approximately 50 degrees at maturity. The tangential radiologic assessment of lumbar lordosis method is more reproducible and more reliable in the lumbar lordotic curve, providing a smaller range of normal values (8 degrees-16 degrees less) than the Cobb method.

Thoracic and lumbar vertebral trauma.

Injuries to the thoracic and lumbar vertebral column are common. They are all the result of increased loading on structures with limited flexibility. The majority of these injuries are related to hyperflexion. Plain radiography remains the mainstay of diagnosis of vertebral injuries. However, CT and MR imaging have important places in assessing patients with vertebral injuries. The radiographic assessment of these injuries is made easier by the fact that each injury occurs in a predictable and reproducible pattern that is defined by the mechanism. These features are termed the "fingerprints" of injury and indicate the full extent of damage. By recognizing the fingerprints and carefully evaluating the patient for abnormalities of alignment, bony integrity, cartilage or joint space, and soft tissues, it is possible to determine rapidly the full extent of injury and plan further evaluation and treatment. Instability may be assumed if there is displacement, widening of the interspinous space, widening of facet joints, widening of the interpediculate distance, or disruption of the posterior vertebral body line.

Clandestine femoral neck fractures with ipsilateral diaphyseal fractures.

We present a protocol for diagnosis of all femoral neck fractures associated with ipsilateral femoral diaphyseal fractures. A 30% incidence of delayed diagnosis has been reported by other investigators. Between 1982 and 1990, we have treated 32 patients with ipsilateral femoral neck and shaft fractures due to blunt trauma. Only 22 femoral neck fractures were diagnosed on prediaphyseal fixation radiographs. This left the 10 patients in this study who had normal prediaphyseal fixation radiographs and were subsequently found to have femoral neck fractures. The ipsilateral femoral neck fractures were found through a retrospective chart and radiographic review of all 555 femoral diaphyseal fractures identified through our trauma and fracture registries. The clinical and radiologic techniques for diagnosing the femoral neck fractures were presented. The time to union of the femoral shaft and neck was determined, and a preliminary radiologic assessment of the vascularity of the femoral head was made. Ten femoral neck fractures (31%) with normal preoperative radiographs were diagnosed after femoral diaphyseal fixation. One patient did not have a post-diaphyseal fixation radiograph. An incidental radiograph at 6 weeks showed a mildly displaced femoral neck fracture in an asymptomatic patient. At 16 weeks the patient became symptomatic, and a repeat radiograph showed the fracture. Five fractures were diagnosed in asymptomatic patients on routine post-femoral fixation radiographs. Two patients had normal post-femoral fixation radiographs, became symptomatic, and had their femoral neck fractures diagnosed on repeat radiographs at 3 and 7 days. One patient had normal pre- and postfixation radiographs, and on a 25-day routine femoral radiograph, the femoral neck fracture was diagnosed.(ABSTRACT TRUNCATED AT 250 WORDS)

The abduction lordotic view of the clavicle: a new technique for radiographic visualization.

The abduction lordotic view is a previously unreported radiographic technique for visualization of the clavicle. Use of this technique, a simple office procedure, combined with a standard anteroposterior view allows almost 90 degrees visualization of the clavicle. It is recommended particularly for the assessment of clavicular healing.

Absent cord sign in acute spinal trauma.

Review of magnetic resonance imaging (MRI) findings in 100 patients suffering acute spinal trauma from 1985 to 1987 revealed four patients who had suffered thoracic spine fractures and acute subarachnoid hematomas. The spinal cord was not demonstrated on the T1-weighted sagittal MRI due to the similarities in signal intensity between the spinal cord and acute hemorrhage. Nonvisualization of the thoracic cord should not be presumed to be artifactual until subarachnoid hematoma is excluded.

Ankle trauma.

Fractures and dislocations about the ankle joint are common injuries. The radiographic "fingerprints" produced by these injuries are directly related to the mechanism that produced that injury. Radiologists must recognize all of the aspects of a particular injury and communicate this information to the orthopedic surgeon because treatment is predicated on recognition of all of the components of the injury. Treatment also depends on restoration of anatomic contour to the articular surface of the ankle joint as well as to reestablishing stability. Plain films, polydirectional tomography, CT, and MRI are useful for evaluating these abnormalities.

Evaluation of cervical vertebral injuries.

The use of imaging studies on patients with suspected cervical vertebral injury should be restricted to those patients who fall into the high-risk category for injury. Once a decision is made to obtain radiographs, a minimum of five views is required to adequately rule in or rule out injury. Complex imaging studies such as CT, polydirectional tomography, and MRI may be performed to confirm the initial impression based on plain radiographic findings. The diagnosis of cervical injuries may be facilitated by following a logical pattern of analysis searching for abnormalities of alignment and anatomy, of bony integrity, of the cartilage or joint spaces, and of the soft tissues. This ABCS approach should simplify an intimidating subject and insure a confident radiological diagnosis.

Imaging of facial trauma.

Severe facial fractures produce a variety of radiographic and CT abnormalities. Careful evaluation of plain films and any CT images should allow rapid and accurate diagnosis of the extent of injury. Table 3 summarizes the radiographic findings seen in the severe mid facial fractures.

Visual illusions in the interpretation of the radiographic image.

The human body is a complex of tissues of different radiographic densities. Overlapping shadows, differences in background density, subjective contour formation, and the parallax effect often produce a variety of optical illusions that exist only in the "mind's eye" and may be mistaken for significant pathology. Most of these phenomena are produced by the Mach effect, a consequence of the physiological process of lateral inhibition. Subjective contour formation is a "psychophysiological" phenomenon in which complete "structures" appear from minimal outlines. A parallax effect occurs if real structures contribute to the radiographic image. This review discusses the basic physiology involved in image reception and the formation of false images. Clinical consequences of the presence of Mach bands, background density effect, subjective contours, and real or physical phenomena are illustrated.

Injuries in amateur ice hockey: a two-year analysis.

A compilation of injuires sustained in an amateur ice hockey program over a tw0-year period revealed that the majority of those injuires were facial lacerations. The number of injuries increased with the level of players' skill and with the intensity of the games. Youth players who were required to wear head and total face protection had fewer injuries than either the adult league or semi-professional players. Injuries were greatest to the semi-professional players who wore little or not head protection, and no facial protection. Physicians have a duty to urge all hockey players to wear adequate head and face protection to prevent such injuries. Equipment which is currently available is illustrated.

Trauma radiology: an integrated approach.

A program at Allegheny General Hospital, Pittsburgh, integrated active radiologic participation with the services of the trauma team and emergency department. Two target areas served as objective criteria for the program's effectiveness: the time patients spent in the emergency department and the number of patients in whom vital diagnostic information was immediately obtained because of direct radiologic participation. This report outlines how the services were integrated and details our results in the two target areas studied.