PubMed Health⌕ Search

Biomedical subjects

A G Thompson

Publications and source records attributed to A G Thompson.

At least 19 recordsLinked to original sources
PubMed2005

Infantile scoliosis in Beals syndrome: the use of a non-fusion technique for surgical correction.

Beals syndrome (congenital contractural arachnodactyl) is a genetic disorder of the connective tissue phenotypically related to Marfan syndrome. It is characterised by dolichostenomelia, arachnodactyly, multiple joint contractures, crumpled ears, hypoplastic muscles and scoliosis. The latter, the most important clinical feature of this rare condition, presents in the infantile and juvenile age group and has a tendency to rapid progression. Bracing often fails to control the scoliosis and surgery is the recommended treatment. We present our experience of two cases managed with the paediatric Isola instrumentation and a non-fusion technique.

Child, Preschool↗
PubMed2004

Emissions of N2O and CH4 during the composting of liquid swine manure.

Composted organic wastes have been shown to reduce emissions of N2O and CH4, but little is known about the release of these gases during the composting process. This research examined the emissions of N2O and CH4 during the composting of liquid swine manure and wheat straw at two operations, one with forced aeration and the other without. The lack of aeration increased CH4 emissions to 24 times that of composting with aeration, but had no significant effect on N2O production. When total N2O and CH4 emissions from composting were compared with liquid swine manure emissions, aerated composting was found to reduce emissions to as low as 30% of those from liquid manure storage, while non-aerated composting elevated emissions up to an estimated 330% of liquid manure storage.

Animals↗
PubMed2004

Do post-take ward round proformas improve communication and influence quality of patient care?

The post-take ward round is a critical time for reviewing the initial history, examination and results, and the stage at which further treatment and investigations will be determined. However documentation of this ward round is often inadequate, so the benefits of decision making are lost. The documentation of 95 ward rounds was assessed for key items of information before and after the introduction of a proforma sheet. The introduction of the proforma led to a significant improvement in the documentation of a diagnosis, management plan, prophylaxis for deep vein thrombosis, and resuscitation status (p<0.05), which will have a significant impact on patient care.

Decision Making↗
PubMed2002

Regional differences in incidence of gastric and colonic cancer in the Maori of New Zealand.

BACKGROUND: It is known that there are ethnic differences in cancer in New Zealand between Maori (the indigenous people) and non-Maori, however, until now no regional comparisons have been made. STUDY DESIGN: A retrospective study of patients diagnosed at Whangarei Hospital, New Zealand between 1995 and 1997 with gastric or colonic cancer was combined with population data from the 1996 census for Whangarei District to calculate incidence figures. The incidence of cancer was compared to national rates. RESULTS: Between 1995 and 1997, 19 Maori and 24 non-Maori were diagnosed with gastric cancer, and 10 Maori and 125 non-Maori with colonic cancer. The age standardised rates (per 100,000) for Maori and non-Maori with gastric caner were 68.3 and 7.9 respectively. Gastric cancer is known to be increased in the Maori, but in Whangarei was significantly higher than the national Maori rates (20.5). There was no difference in the rate of colonic cancer in the Maori and non-Maori in Whangarei, again this differs from the national trends, in which the Maori are protected against cancer. CONCLUSION: This study highlights that there is still much more to be learnt in understanding the aetiology of gastrointestinal cancers, to explain such strong regional differences.

Adult↗
PubMed2000

A simplified Galveston technique for the stabilisation of pathological fractures of the sacrum.

Mechanical stabilisation of pathological fractures of the sacrum is technically challenging. There is often inadequate purchase in the sacrum, and stabilisation has to be achieved between the lumbar vertebrae and ilium. We present a simplification of the Galveston technique. We treated a total of six patients with this technique, four for metastatic disease and two for primary tumours. Our technique consists of the formation of a proximal stable construct using ISOLA pedicle screws linked distally using a modular system of connectors to threaded iliac bolts with cross linkages. Neurological decompression and fusion was performed as appropriate. The benefits of this method are: ease of access to the ilium, a solid purchase to the ilium, less rod contouring and shorter operating time. We have had no operative complications from this procedure. All patients were discharged home mobile, with a reduced opiate requirement.

Adolescent↗
PubMed1998

Autologous bone grafting in staged scoliosis surgery. The patient as bone bank.

STUDY DESIGN: A prospective clinical study in which autologous rib graft, harvested during the thoracotomy in staged scoliosis correction, is stored within the patient for use during the second stage (posterior intrumentation and fusion). OBJECTIVE: To determine whether the bone stored by this technique is biologically viable and microbiologically safe. SUMMARY OF BACKGROUND DATA: To the authors' knowledge, this method of storage of bone has never been described previously. METHODS: During the first operation, the excised rib was divided into 3-5 cm fragments and stored in a sub-muscular plane adjacent to the posterior elements of the spine before closure. The graft was then retrieved at the second stage. Samples were sent for histologic and microbiologic examination before implantation. RESULTS: On histologic examination, more than 50% of the osteocytes retained their basophilic staining, indicating that they were viable. In addition, osteoclastic activity was notably absent. There was no significant bacterial contamination of the samples. Clinically, all patients achieved satisfactory bone fusion. CONCLUSION: Homeostatic equilibrium in humans provides the ideal environment in which bone graft can be stored. There is no increased risk of infection, and the osteogenic potential of the graft is retained.

Bone Transplantation↗
PubMed1996

Convex spinal epiphysiodesis in the management of progressive infantile idiopathic scoliosis.

STUDY DESIGN: Retrospective review of patient records with current clinical and radiographic assessment. OBJECTIVE: To evaluate the long-term result of anterior and posterior convex spinal growth arrest, with or without instrumentation, in managing infantile idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: There were 12 male and 10 female patients studied, with a mean follow-up period of 10 years, 9 months. The mean Cobb angle before surgery was 65 degrees. All had a rib vertebral angle difference more than 20 degrees. The mean age at surgery was 6 years. Nine patients had epiphysiodesis alone; nine patients also underwent Harrington instrumentation simultaneously, and four underwent Harrington instrumentation 2-4 years later. METHOD: Clinical evaluation and sequential measurements of Cobb angle were done. RESULTS: The epiphysiodesis-only group had a mean preoperative Cobb angle of 72 degrees, mean progression of curves of +12 degrees, and mean rate of progression of +2.5 degrees per year: the group's postoperative figures were 92 degrees, +15 degrees, and +3 degrees per year, respectively. The epiphysiodesis and late Harrington rod group had a mean preoperative Cobb angle of 56 degrees, mean progression of +12 degrees, and a mean rate of progression of +5 degrees per year; the group's postoperative Cobb angle averaged 62 degrees, progression +6 degrees, and rate of progression +1 degree per year. The epiphysiodesis with simultaneous Harrington rod group had a preoperative mean Cobb angle of 60 degrees, mean progression of +18 degrees, and mean rate of progression of +6 degrees per years. After surgery, these improved to 58 degrees, correction of 2 degrees, and rate of correction of 0.5 degree per year. CONCLUSION: Combined anterior and posterior convex spinal growth arrest alone does not prevent progression of deformity in infantile idiopathic scoliosis. The addition of posterior instrumentation can slow or arrest deformity progression but not reverse it.

Bone Nails↗
PubMed1996

Atlantoaxial instability in Lesch-Nyhan syndrome.

STUDY DESIGN: A clinical case report of two brothers with Lesch-Nyhan syndrome found to have atlantoaxial instability is reported. OBJECTIVES: To report the clinical and radiologic findings and the operative outcome in these patients. SUMMARY OF BACKGROUND DATA: Both patients had biochemically proven Lesch-Nyhan syndrome. No previous cases of cervical instability have been reported in this group of patients. METHODS: The first patient presented with neck pain and progressive quadriplegia. Radiology including computed tomography scanning showed fracture of the tip of the odontoid and forward subluxation of the atlas. He was treated with a C1-C2 Gallie fusion. The second patient (his brother) was found to have similar radiologic findings but had not developed quadriplegia. He has not required surgery. RESULTS: At surgery, attempted correction of the subluxation produced severe bradycardia. An in situ fusion was performed that relieved the patient's neck pain. The child's neurologic status has remained the same during a 16-month follow-up period, despite failure of the posterior wire fixation 12 months after surgery. CONCLUSIONS: Patients with Lesch-Nyhan syndrome may develop atlantoaxial instability with subsequent neck pain and quadriplegia that may be masked by their underlying disease. Posterior fusion produced symptomatic relief but no improvement in neurologic status in our patient. Posterior fusion probably should be augmented by rigid cervical immobilization until fusion is confirmed in this type of patient.

Adolescent↗
PubMed1995

Long-term results of combined anterior and posterior convex epiphysiodesis for congenital scoliosis due to hemivertebrae.

STUDY DESIGN: Retrospective review of patient records with recent clinical and radiologic assessment. OBJECTIVE: To evaluate the long-term result of anterior and posterior convex ephiphysiodesis in the management of congenital scoliosis resulting from fully segmented nonincarcerated hemivertebra. SUMMARY OF BACKGROUND DATA: Thirty patients (16 male/14 female patients) were reviewed. Follow-up was a minimum of 3 years (average, 8 years 10 months; range, 3-22.5 years). Nineteen patients were skeletally mature, and the mean age of the remaining 11 was 11.75 years. METHOD: Clinical evaluation and sequential measurements of Cobb angle was made independently by two observers. RESULTS: Compared with preoperative values, the rate of change in Cobb angle was reversed in 23 patients, arrested or slowed in five patients, and unchanged or progressed in two patients. The annual rate of change in Cobb angle was +1.9 degrees before surgery and -1.2 degrees after surgery, a difference of 3.1 degrees. This is highly statistically significant (P < 0.001). Total correction in Cobb angle correlates with age at time of surgery (P < 0.03). The rate of correction in Cobb angle after surgery correlates with the total correction achieved (P < 0.001) and with age at time of surgery (P < 0.05). The greater correction is achieved when surgery is performed at a young age. The preoperative rate of increase in Cobb angle does not correlate with correction (P < 0.76). The site of the hemivertebrae influenced final outcome with best results in the lumbar spine. CONCLUSION: Combined anterior and posterior convex epiphysiodesis is a reliable method for the correction of deformity resulting from hemivertebrae.

Child↗
PubMed1995

Surgical management of haemangioendothelioma of the spine.

Four patients with haemangioendothelioma of the spine which was treated surgically are presented. Two were male and two female, mean age 30 years (range 5-60). All tumours were sited in the thoracic spine between T5 and T10; three were primary and one metastatic from a hepatic haemangioendothelioma. Each patient had a significant neurological deficit at presentation; three were paraplegic. A diagnosis of vertebral neoplastic disease was suggested on plain radiographs, and in three cases this was supported by computed tomography or magnetic resonance imaging. Two patients underwent anterior decompression and posterior instrumented stabilisation, one anterior decompression alone and one posterior decompression followed by tumour vessel embolisation and then anterior decompression. Intra-operative blood loss was a significant feature despite the use of hypotensive anaesthetic techniques and local haemostatic agents. Three of the tumours were tested for Factor VIII (a tumour for vascular tumours), and all proved positive. In these, sufficient histological material was available to grade the tumours according to the classification of Campanacci et al. [1]. All were grade II. Three patients recovered completely from paraglegia; one had residual mild spasticity which required the use of a walking aid. The mean improvement in Frankel grade was 2.5 (range 1-4). In two the tumour recurred outside the spine within 18 months; one had subsequently died. The presentation, investigation and results of surgery for haemangioendothelioma of the spine are presented. Particular attention is drawn to the neurological status at presentation, the effect of pre-operative tumour embolisation and the dramatic recovery that can be achieved in these patients following surgery.

Adult↗
PubMed1995

Long-term results of convex epiphysiodesis for congenital scoliosis.

The objective of this study was to evaluate the long term outcome of combined anterior and posterior convex spinal epiphysiodesis in the treatment of congenital scoliosis. The study covered 53 patients (27 male, 26 female) with a minimum follow up period from surgery of 3 years (mean 8.8 years, range 3-22.5 years). Of these, 34 were skeletally mature when reviewed. Clinical assessment and sequential measurement of Cobb angles were used to chart the course of the deformity following surgery. The types of vertebral anomalies encountered were: 4 unsegmented bars, 7 unsegmented bars with hemivertebrae, 30 hemivertebrae (of which 2 were double hemivertebrae) and 12 complex (unclassifiable) patterns. The severe types were concentrated in the thoracic spine. Results are presented with reference to the type and site of anomaly and to the age of the patient at the time of surgery. Where deformity was due to an unsegmented bar (with or without hemivertebra) the rate of change of Cobb angle was slowed, but not reversed, following surgery. For the complex anomalies there was a reduction in the rate of progression of deformity following surgery, however, the final Cobb angle still increased from a mean of 61 degrees to 70 degrees. In contrast, the rate of progression reversed or slowed in 97% of the hemivertebra patients following surgery, producing a change in mean Cobb angle from 41 degrees pre-operatively to 35 degrees post-operatively. For each type of anomaly the correction achieved was greater where the surgery was performed at a younger age. Final outcome was influenced by the site of anomaly, with a better correction being achieved in the lumbar than the thoracic spine. In conclusion, we feel that convex epiphysiodesis has an important role in the surgical management of congenital scoliosis and, for hemivertebrae in particular, it can produce significant correction of deformity.

Child↗
PubMed1995

Expectations as determinants of patient satisfaction: concepts, theory and evidence.

The apparent lack of conceptual agreement and the inconsistency in the approach to understanding expectations prompted this analysis of the literature in the field of patient satisfaction. A review of 18 journals over the last few years, as well as a number of relevant books, provided the evidence for the state of the current theory. An attempt has been made to distill the main definitions in use, to illustrate practical models of the relationship between expectations and satisfaction, to identify the influential personal and social variables, and to consider the special nature of health care. Some of the empirical methods and findings are then presented, with conclusions made about how the theory of expectations may be developed to assist in understanding patient satisfaction.

Attitude to Health↗
PubMed1994

Surgical management of vertebral neoplasia: who, when, how and why?

To determine the role of surgery in vertebral neoplasia, we conducted a retrospective review of patients undergoing surgery for vertebral neoplasia in the Royal Orthopaedic Hospital, Birmingham, and Coventry and Warwickshire Hospital, Coventry. Surgery included decompression, stabilisation or both. The neurological status was assessed by Frankel grading before and after surgery. Of 70 patients undergoing surgery, 14 were neurologically intact preoperatively, and a further 25 were weak but ambulatory. Following surgery, 35 were intact, and a further 22 were ambulatory. Sixty-six patients (94%) obtained good pain relief. Survival correlated with histology and younger age at presentation, but not with level, neurology at presentation or type of surgery. We conclude that neurological status, pain relief and mechanical stability are better after appropriate surgery than after radiotherapy or inappropriate surgery. Failure to consider the surgical option may deny the chance of significant neurological recovery.

Bone Transplantation↗
PubMed1993

A halo jacket for stabilisation of the paediatric cervical spine.

Stabilisation of the paediatric cervical spine may be necessary in the management of trauma, infection and deformity. Surgery is technically difficult due to the immaturity of the bony elements and therefore external support is generally preferred. Our experience of halter traction and Minerva casts is that they either fail to achieve stability or are poorly tolerated. Halo pins are associated with significant pin tract complications in children. The technique for application of a plaster halo jacket is presented, together with the results of its use in eight children. Attention is drawn to the ease of application, tolerance by the patients and absence of significant complications.

Cervical Vertebrae↗
PubMed1992

The Scott wiring technique for direct repair of lumbar spondylolysis.

Between 1979 and 1989, we treated 22 patients with symptomatic lumbar spondylolysis which had not responded to conservative treatment by a modified Scott wiring technique to give direct repair of the lytic defects with stabilisation. The patients' mean age at the time of operation was 15 years; the mean follow-up period was four years. All 19 patients under 25 years old had satisfactory results. Two of the three patients over 25 years old had poor results. The age of the patient at surgery seems to be an important determinant of outcome. Radiologically confirmed fusion is of secondary importance. The presence of a grade I spondylolisthesis did not prejudice the result. We recommend the Scott wiring technique to stabilise the direct repair of a lumbar spondylolysis.

Adolescent↗
PubMed1990

Pullout force of power-driven staples in cadaveric femoral metaphysis.

The maximum pullout force in the distal metaphysis of cadaver femurs was investigated using a commercially available, pneumatically inserted staple. In paired studies, a significantly greater pullout force was required in the power-driven staples than in an almost identical sized hand-driven staple. A nonlinear relationship was shown to exist between staple-leg length and maximum pullout force.

Adult↗