Biomedical subjects

R A Douglas

Publications and source records attributed to R A Douglas.

12 recordsLinked to original sources

PubMed1996

Retroperitoneal pseudomeningocele complicated by meningitis following a lumbar burst fracture. A case report.

STUDY DESIGN: This case report demonstrates an unusual complication after anterior decompression and fusion of a lumbar burst fracture. OBJECTIVES: The treatment of this patient involved placement of a computed tomography-guided percutaneous drain and intravenous antibiotics to treat an infected retroperitoneal pseudomeningocele. SUMMARY OF BACKGROUND DATA: A case of an anterior retroperitoneal pseudomeningocele complicated by meningitis is presented. This pseudomeningocele occurred in a patient after an L3 burst fracture associated with a dural laceration. METHODS: The patient was admitted to the authors' trauma unit after a motor vehicle accident with an acute L3 fracture associated with incomplete paraplegia. He underwent an urgent anterior corpectomy, strut grafting, and instrumentation. At surgery, he was noted to have a large anterior dural laceration. After surgery, a large retroperitoneal pseudomeningocele developed that became infected with Staphylococcus epidermidis. RESULTS: After placement of a computed tomography-guided percutaneous drain and intravenous antibiotics, the pseudomeningocele resolved. His anterior fusion healed uneventfully and his neurologic deficit improved dramatically. CONCLUSIONS: A case of an anterior retroperitoneal pseudomeningocele complicated by meningitis is presented. This pseudomeningocele occurred in a patient after an L3 burst fracture associated with a dural laceration. The patient was treated successfully with computed tomography-guided percutaneous drain placement and intravenous antibiotics. He made an excellent functional recovery after a severe neurologic injury.

Adolescent↗

PubMed1995

Biomechanical evaluation of cervical spine stabilization methods using a porcine model.

STUDY DESIGN: The biomechanical stability of three different methods of cervical spine stabilization was evaluated in a porcine model. Specimens were tested in flexion, extension, and axial rotation. OBJECTIVES: Our goal was to determine if posterior lateral mass plating after anterior reconstruction provided more stability compared with unicortical or bicortical anterior plate fixation after a simulated corpectomy. SUMMARY OF BACKGROUND DATA: Previous implant biomechanical evaluations use ligamentous and intervertebral disc disruption models under constrained and nonrepetitive loading. This study examines implant performance using a corpectomy model loaded for multiple cycles, allowing for unconstrained motion. METHODS: Twenty-one porcine cervical spines were destabilized with a one-level cervical corpectomy and reconstructed with an anterior methacrylate graft. Each construct was stabilized with either an AO Morscher plate system with unicortical, self-locking screws; a Caspar plate with biocortical screws; or two posterior lateral mass plates. Testing with cyclic loads was performed on an MTS machine in flexion, extension, and axial rotation. RESULTS: There was no statistical difference between the two anterior forms of fixation in flexion, extension, or axial rotation. Posterior lateral mass plating was significantly more stable than either anterior construct. Screw loosening was seen more frequently with bicortical Caspar plating. CONCLUSIONS: After a single-level cervical corpectomy and idealized grafting, all three surgical constructs provided stability equal to or greater than the intact condition in flexion, extension, and axial rotation. In unstable cervical spine injury patterns involving anterior disruption, this study supports the use of anterior grafting combined with posterior lateral mass plating to achieve maximum stability.

Animals↗

PubMed1992

Complications in three-column cervical spine injuries requiring anterior-posterior stabilization.

A study was undertaken to elicit the hidden factors that, when identified, would signal the presence of cervical spine instability. Data were derived from the records and radiographs of 21 patients having sustained traumatic injury to the lower cervical spine (C3-C7) and who failed a single-stage posterior stabilization procedure necessitating a second (or combined) anterior-posterior arthrodesis. Mechanism of injury most frequently identified in this group was the distraction-flexion (locked facets) pattern (nine patients) and the "tear drop" compression-flexion injury pattern (seven patients). All 21 patients underwent a posterior wiring and bone graft stabilization procedure with persistent postoperative instability. Thus, failure to recognize the presence of "three-column" instability, the sine qua non of this group, resulted in the failure of posterior tension band stabilization as a means of gaining cervical spine stability. Three-column cervical spine instability is suspected in the presence of: 1) retrolisthesis and angulation of the superior vertebra on the next inferior vertebra; 2) distraction of the posterior interspinous ligaments sufficient to allow subluxation or dislocation of the facets; in conjunction with 3) a "shear" dislocation of one vertebra on another. Anterior shearing force through the disc space is capable of disrupting the intervertebral disc, along with disruption of the anterior and posterior longitudinal ligaments, each contributing to the presence of anterior and middle column cervical spine instability.

Adult↗

PubMed1992

Management of cervical spinal cord trauma.

Trauma victims with cervical spinal cord injuries should be managed by proper immobilization and immediate reduction of spinal cord fractures to anatomical alignment. Patients must be stabilized medically, and a thorough neurologic and radiographic evaluation must precede any surgical intervention. Treatment must be individualized and depends on the level and severity of injury. New pharmacotherapies under intensive investigation offer some hope of recovery of function to patients with spinal cord injuries. Recent clinical trials with methylprednisolone indicate that the sensory and motor outcome of patients subject to trauma with spinal cord injuries improved when they received high doses within 8 hr of injury. Clinical trials are being proposed with tirilizad, a member of a new family of drugs, the 21-aminosteroids. This agent, which may be even more effective than methylprednisolone, has none of the side effects associated with other steroids.

Accidents, Traffic↗

PubMed1990

Management of spinal cord trauma.

Spinal cord injuries disproportionately affect young males in their peak wage-earning years, with catastrophic personal and economic consequences. New pharmacological and surgical interventions have evolved from extensive research on the pathophysiology and biomechanics of SCI. Management of SCI must be individualized and will depend on the level and severity of the injury and the patient's medical condition. Rehabilitation is integral to the treatment of SCI to help patients achieve their highest possible level of function. Prevention of spinal cord injuries, however, is the optimal strategy, and neurosurgeons should actively participate in prevention programs.

Cervical Vertebrae↗

PubMed1981

Possible mechanism of action of cholesterol enriched diet on the thyroid.

Groups of male Sprague Dawley rats aged 60 days were fed either a control diet (CD) or the same diet enriched with 1% cholesterol (CHD) for 30 days. In CHD fed animals an increase of 131I uptake by thyroid, PB131I and TSH level in plasma was found, while the level of thyroxine (T4) was unchanged and that of triiodothyronine (T3) was decreased. In the animals treated with T3 (20 micrograms i.p. daily) a decrease of 131I uptake by thyroid and of T4 and TSH level in plasma was found irrespectively of a cholesterol content in the diet. However, PB131I level was decreased in CHD fed and T3 treated animals compared to those fed CD under the same treatment. Finally, in the animals treated with cimetidine (10 mg i.p. daily) no changes of any measure was found after CD feeding as compared to untreated ones, while CHD in such animals resulted in a decreased of T3 level. The site of cholesterol action appears to be at the hypothalamus-pituitary system since TSH suppressed animals (i.e. T3 treated) did not show any thyroid stimulation when fed with a cholesterol excess. Furthermore, thyroidectomized animals showed increased TSH in plasma after cholesterol feeding. In the present study, chronic administration of cimetidine completely abolished thyroid gland stimulation promoted by cholesterol feeding thus suggesting that central histamine may play a considerable role in this process.

Animals↗

PubMed1980

Meliodosis.

During the five-month wet season of 1977-1978 in Northern Queensland, six patients with bacteriologically proven melioidosis were successfully treated at the Townsville General Hospital, The clinical course and management of each case and laboratory findings are described. Factors which predisposed them to infection with Pseudomonas pseudomallei were diabetes mellitus, cancer, alcoholism, malnutrition, trauma, and pregnancy. Successful treatment of melioidosis relied on prompt laboratory diagnosis and appropriate chemotherapy together with surgical drainage of abscesses and management of concomitant diseases. The incidence of melioidosis in Northern Queensland has increased to the extent that it can no longer be considered a rare disease in this area. Because of increased internal and international travel, and displacement of refugees from endemic areas of Southeast Asia, physicians and microbiologists must maintain a high index of suspicion of melioidosis when dealing with patients after geographic exposure, as it is probable that, in the future, this disease witll be encountered more frequently in non-endemic areas.

Adult↗

PubMed1977