Search PubMed⌕ Search

Biomedical subjects

J H Harris

Publications and source records attributed to J H Harris.

At least 55 records · Page 3Linked to original sources
PubMed1986

Hyperextension dislocation of the cervical spine.

The purpose of this report is to describe hyperextension dislocation of the cervical spine and to illustrate its often subtle radiographic features. An analysis of the lateral cervical spine radiographs in 20 patients with hyperextension dislocation of the cervical spine revealed the combination of diffuse prevertebral soft-tissue widening together with normally aligned cervical vertebrae in all patients with this injury. In six (30%) of 20 patients, this combination of findings was the only radiographic sign. The precise level of dislocation was indicated by a thin, transversely oriented avulsion fracture fragment arising from the anterior aspect of the inferior end-plate of the dislocated vertebra in 13 (65%) of 20 patients, by a vacuum defect in the intervertebral disk subjacent to the dislocated vertebra in three (15%), by a widened intervertebral disk space in three (15%), and by comminuted fracture of the spinous process in one (5%). Clinically, all 20 patients had facial trauma and all had some manifestation of the acute central cervical spinal cord syndrome.

Adolescent↗
PubMed1986

A practical classification of acute cervical spine injuries.

This article presents a practical classification of acute cervical spine injuries based on terminology with generally accepted and understood definitions, published results of experimentally produced acute injuries of the cervical spine, and the correlation of the radiographic and pathologic characteristics of the laboratory models with acute clinical injuries.

Acute Disease↗
PubMed1986

Radiographic evaluation of spinal trauma.

This article reviews the general principles that apply to the radiographic evaluation of acute injury of the cervical and thoracolumbar spine and discusses the possible use of various imaging techniques.

Acute Disease↗
PubMed1984

Low (type III) odontoid fracture: a new radiographic sign.

Dens fractures are frequently difficult to identify radiographically, particularly when it is only possible to obtain a lateral radiograph of the upper cervical spine. Further, when a dens fracture is identified in lateral projection, it is often difficult to distinguish the "high" (Type II) from the "low" (Type III) fracture. The authors describe an elongated "ring" density superimposed upon the body of the axis in the lateral cervical radiograph which, when horizontally disrupted, indicates a dens fracture and is a specific radiographic sign of the "low" variety.

Axis, Cervical Vertebra↗
PubMed1984

An approach to mid-facial fractures.

The purpose of this article is to present a concept which facilitates the plain film identification of mid-face fractures. The concept evolves from a logical classification of mid-face fractures based upon the region(s) of involvement (orbit, zygoma, maxilla), the extent of the fractures (unilateral or bilateral) and the characteristic distribution of the fracture lines. Recognition of these fractures depends upon an awareness of the fact that the radiographic signs of mid-face fractures differ in certain respects from those involving other skeletal parts. In addition to skeletal disruption, the radiographic signs of mid-face fractures include soft tissue abnormalities which may be localized or diffuse, and which may be either extrinsic or intrinsic to the facial skeleton, alterations of normal skeletal contour, the "bright white line" of displaced fragments, and the subcutaneous emphysema which may also be localized or diffuse. The application of this concept to the roentgen diagnosis of mid-face fractures will be described and illustrated.

Adult↗
PubMed1983

Antecedents of psychological stress.

In an effort to further understand the antecedents of psychological stress, this study tested two competing stress formulations. One formulation, called the traditional model, proposes that stress is a multiplicative function of perceived consequences and the degree of disparity between perceived demand and perceived ability. Given high consequences, stress is presumed to reach its maximum when demand is substantially greater than ability (overload) or when ability is substantially greater than demand (underload). The other formulation, the revised model, proposes that stress is a multiplicative function of perceived consequences and the degree of correspondence between perceived demand and perceived ability. Stress is presumed to reach its maximum when high consequences are combined with a close match between demand and ability resulting in high uncertainty. The formulations were tested in a naturally occurring stress setting, a classroom which required students to give class presentations. The results offered substantial support for the proposition that overload situations are stress inducing, no support for the traditional model's position that overload and underload conditions are equally stressing, and no support for the revised model. Also, stress varied independently of perceived consequences. Several methodological issues were discussed, including a crucial one questioning the use of absolute levels of discrepancy rather than signed levels of discrepancy between perceived ability and demand in the models.

Achievement↗
PubMed1982

The sacral arcuate lines in upper sacral fractures.

The anteroposterior radiographs of 50 patients with multiple fractures of the pelvic ring were analyzed and the findings compared with the interpretation made at the time of admission. Thirty-six of the 50 patients (72%) had associated sacral fractures. Sixty-one percent of the sacral fractures had been missed on the initial examination. Disruption, displacement, deformity, and density changes of the sacral arcuate lines are described as signs of sacral fracture.

Fractures, Bone↗
PubMed1982

Computed tomography-guided intracranial biopsy and cyst aspiration.

A coordinated series of instruments has been developed for use in computed tomography (CT)-guided brain lesion biopsy and cyst aspiration: a plastic guide needle that is relatively free of CT artifacts, a ball-and-socket holding device for multidirectional sampling, and an aspiration-cutting biopsy needle that reliably produces consistent cores of tissue. Twenty-six biopsy and/or aspiration procedures have been performed on 24 patients with an overall biopsy success rate of 79%. The method is most reliable with highly malignant astrocytomas and least reliable with metastases and unusual primary tumors. There were 3 complications: 2 intratumoral hematomas and 1 death due to hemorrhage. A survey of published CT biopsy series shows an overall success rate of 85%. The rate of serious complications is 3.5% (including 3 deaths). The incidence of intratumoral hematomas that are clinically silent or associated with relatively minor clinical problems is 9%. CT-guided intracranial biopsy is more reliable than the earlier freehand methods and simpler than stereotactic techniques. It is the procedure of choice for percutaneous biopsy of superficial and deep hemispheric lesions.

Biopsy, Needle↗
PubMed1981

Posterior urethral injuries after pelvic fracture.

Rupture of the posterior urethra is an uncommon but serious complication of anterior pelvic arch fracture. It is commonly believed that such injuries occur at the apex of the prostate and on urethrography result in extravasation of contrast material above the urogenital diaphragm. In 1977, Colapinto and McCallum proposed a different classification of such injuries. This paper presents experience in 18 proven cases of posterior urethral injury using this new classification. All patients were studied with retrograde urethrography before any attempt at urethral catheterization. The data support the contention that the traditional concept of posterior urethral injury is, in fact, unusual. Of 18 patients, 12 had complete or partial urethral injuries extending both above and below the urogenital diaphragm as demonstrated by urethrography. Only three of 18 patients had the classical injury, that is, extravasation into pelvic fascial planes limited inferiorly by an intact urogenital diaphragm.

Adult↗
PubMed1981

The importance of soft tissues in certain skeletal traumatic lesions.

Soft tissue aspects of skeletal trauma are discussed according to two categories: (1) those injuries in which the significance of the soft tissue in the pathophysiology of the skeletal lesion is indicated by the characteristics of the skeletal injury (such as extension teardrop fracture, little leaguer's elbow, "baseball fracture," and Bennett's fracture); and (2) those injuries in which the associated soft tissue injury, or complication, may be reasonably inferred by the location and nature of the skeletal injury (such as major facial fractures, posterior sternoclavicular dislocations, fractures of the lower rib and lumbar transverse processes, and pelvic disruptions).

Ankle Injuries↗