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T Terjesen

Publications and source records attributed to T Terjesen.

At least 73 records · Page 4Linked to original sources
PubMed1986

The extent of stress-protection after plate osteosynthesis in the human tibia.

The extent of stress-protection was investigated in 12 patients with previous tibial fractures treated by steel plate fixation. They were examined by computed tomography (CT) scanning one or two days after plate removal. The cortical density and thickness were determined by the CT scans. In the previously plated segment, a significant reduction in cortical density was found, and the reduction was most pronounced in the quadrant directly beneath the plate. The osteopenia did not increase with increasing duration of plate application in excess of one year. No significant differences in cortical thickness between plated and control tibiae occurred. The results indicate that stress-shielding after rigid plating in the human tibia is less pronounced than that previously reported from experimental studies in animals.

Adolescent↗
PubMed1985

Bone atrophy after plate fixation. Computed tomography of femoral shaft fractures.

Twelve patients with previous femoral shaft fracture treated by rigid plate fixation were examined by computed tomography (CT) scanning 1 or 2 days after plate removal. In the previously plated segment an average reduction in cortical density of 11 per cent was found, and the reduction was most pronounced in the cortex directly beneath the plate. No reduction in cortical thickness of the plated bone occurred. Proximal and distal to the site of the plate, and in the ipsilateral tibial shaft, a slight reduction in cortical density and thickness averaging 2-3 per cent was found.

Adolescent↗
PubMed1984

Bone healing after metal plate fixation and external fixation of the osteotomized rabbit tibia.

Controversy still exists as to the best method of treatment of long bone fractures. The purpose of the present study was to compare the effects on the healing bone of external fixation and metal plate fixation. In an experimental model on the rabbit tibia the stiffness of the fixation corresponded intentionally to that of the same methods in human fracture treatment. A transverse midshaft osteotomy was made on one tibia, and fixed with a steel plate (45 X 5 X 1 mm) or external mini-fixation. The animals were killed after 4, 6 or 12 weeks. The bone healing was evaluated by radiography, histology and biomechanical testing in three-point bending. There were no significant differences between plate fixation and external fixation in the pattern of bone healing, as it occurred by periosteal, intramedullary and intercortical callus after both methods. The stiffness increased more rapidly than the strength, and reached normal values after about 6 weeks. No significant differences in stiffness between the two methods were found. The strength was significantly greater after plate fixation than after external fixation at 6 weeks, while no significant differences were found at either 4 or 12 weeks. It is concluded that the speed of bone healing was more rapid after plate fixation. However, in the later stages of healing the plated bones were secondarily weakened because of the stress-protecting effect of the plate.

Animals↗
PubMed1984

Healing of rabbit tibial fractures using external fixation. Effects of removal of the fixation device.

Bone healing after external fixation of rabbit tibial osteotomies was studied in order to throw light on the problem of the optimal time for removal of external fixation. The animals were divided into various groups according to different periods of time for removal of external fixation and sacrifice. The strength and stiffness of the healing bones at 12 weeks were greater in tibiae where the external fixator was removed at 4, 6 or 9 weeks than in those with the continuous presence of the fixator for 12 weeks. Although fixation is essential in the early healing period, it seems that bone healing is stimulated by the removal of the fixation after a certain period of time. The optimum time for removal of external fixation in the rabbit tibia was at 6 weeks of healing, when the bone had regained normal stiffness and about 50 per cent of normal strength. The clinical relevance of this investigation is that it might be rational to remove the external fixator before bone healing has been completed. If it is felt that healing is not secure when the fixator is removed, a tibial brace might subsequently be used for a short period.

Animals↗
PubMed1984

Plate fixation of tibial fractures in the rabbit. Correlation of bone strength with duration of fixation.

Bone healing after metal plate fixation of rabbit tibial osteotomies was studied in order to gain information as to the optimum time for plate removal. The fracture had regained almost normal biomechanical properties after 6 weeks. Significantly greater strength and stiffness of the healing tibiae were obtained at 12 weeks when the plate was removed after 4, 6 or 9 weeks and no further fixation was subsequently applied, compared to those plated for 12 weeks. The results indicate that a metal plate should be removed as soon as the fracture has regained normal biomechanical properties; i.e. before the stress-protecting effect has secondarily weakened the bone. The findings suggest that metal plates should be removed at an earlier stage of the healing period than is usual in clinical practice.

Animals↗
PubMed1983

Stress-protection after external fixation on the intact rabbit tibia.

Bone loss due to the stress-protecting effect of a metal plate on intact bone is a well-known phenomenon. The purpose of the present study was to find whether a similar effect is caused by external fixation. External mini-fixation was applied on the intact rabbit tibial diaphysis of one leg. The other tibia served as control. The animals were sacrificed after 6 or 12 weeks, and both tibiae biomechanically tested in three-point bending. The bone mineral content was measured by photon absorptiometry. No significant changes in bone strength, stiffness or mineral content were found after 6 weeks. The strength and stiffness were significantly reduced after 12 weeks. The median strength and stiffness at that time were 87 and 88 per cent, respectively, in relation to the control bones. The mineral content in the bone segment which had been stabilized by external fixation was significantly reduced after 12 weeks (median 90 per cent of the values for the control bones). No significant change in the mineral content occurred at a level in the tibial diaphysis distal to the external fixation device. It is concluded that the stress-protecting effect caused by external mini-fixation on the rabbit tibia occurs later, and is less pronounced, than that caused by metal plates.

Animals↗
PubMed1983

The stress-protecting effect of metal plates on the intact rabbit tibia.

The purpose of the present study was to find the extent of stress-protection by a steel plate (45 X 5 X 1 mm) on the rabbit tibia. The animals were sacrificed after 6, 12 and 18 weeks. The median strength after plate application was 84, 73 and 72%, respectively. The elastic stiffness of plated bones was also reduced, while the deformation at fracture showed no significant reduction. The mineral content in the bone segment previously covered by a plate was measured by photon absorptiometry; it was reduced after 12 and 18 weeks. The stress-protecting effect caused by this thin steel plate was less pronounced than that previously reported by groups using more rigid plates on rabbit tibiae. The stress-protecting effect increased up to 12 weeks, but subsequently no further increase occurred.

Animals↗
PubMed1983

In vitro effects of external fixation on intact and osteotomized tibiae. A biomechanical study.

In order to study the in vitro mechanical effects of external fixation on intact and osteotomized bone, human and rabbit tibiae were tested in three-point bending in an Instron testing machine. Intact tibiae were loaded in the elastic range before and after application of an external fixation device. In the human specimens the Vidal-Adrey double frame was used, and in the rabbit specimens the external mini-fixation. The bone deformation in the anteroposterior direction was measured with a linear voltage differential transformer. After application of external fixation a median bone elastic stiffness of 110.2 per cent in human tibiae and of 106.1 per cent in rabbit tibiae was found, in relation to the stiffness of intact tibiae without external fixation. The stiffness increase was significant in human specimens, but not significant in rabbit specimens. In osteotomized human tibiae fixed with the Vidal-Adrey double frame a median stiffness of 8.5 per cent of the stiffness of intact bones was found when compression was not applied, compared to 19.9 per cent when compression was applied. In rabbit tibiae a median stiffness of osteotomized bones with external mini-fixation was 8.9 per cent of the stiffness of intact bones. There was a good agreement between the results in rabbit tibiae with the mini-fixation and human tibiae with external fixation without compression. The external mini-fixation thus seems to be a suitable model for the study of bone healing in rabbit tibiae.

Aged↗
PubMed1983

Mechanical effects of metal plate fixation. In vitro investigation on intact and osteotomized human and rabbit tibiae.

In order to study the in vitro stress-protecting effect on intact bone, and the rigidity of plate fixation on osteotomized bone, human and rabbit tibiae were tested in three-point bending in an Instron testing machine. Intact tibiae were loaded in the elastic range before and after metal plate application. The deformation was measured with a linear voltage differential transformer. In the human specimens a median stiffness increase of 31 per cent was obtained in the plated bone segment after application of a tibial plate (140 x 12 x 4 mm) and of 43.8 per cent after application of a femoral plate (140 x 16 x 5 mm). In the rabbit specimens a median stiffness increase of 31.9 per cent was obtained after application of a thin plate (45 x 5 x 1 mm). In osteotomized human tibiae with tibial plate fixation, a median elastic stiffness of 51.4 per cent of the intact bone was found, compared to 40.4 per cent in osteotomized rabbit tibiae plated with the thin plate. There was good agreement between the results in human tibiae plated with a tibial plate, and rabbit tibiae with the small plate. In previous studies of the stress-protecting effect of internal plate fixation on rabbit tibiae more rigid plates have been used. These plates seem to have been overdimensioned. In further studies in rabbits plates of similar size as the one tested in this study should be applied.

Animals↗
PubMed1982

Increased femoral anteversion and osteoarthritis of the hip joint.

The anteversion angle (AV-angle) of the femur was measured according to the method of Rippstein in a series of 50 patients with "primary" osteoarthritis of the hip, and in a control group of 30 individuals of the same age without hip disease. The median AV-angle of the hips in osteoarthritic patients was 17.5 degrees, and in the control group 13 degrees. Osteoarthritic patients had a significantly increased AV-angle in relation to the control group (P = 0.0028). The greatest AV-angle in the hips of the control group was 25 degrees. In 18 hips of osteoarthritic patients an AV-angle greater than 25 degrees was found. Osteoarthritis was found in 15 of these hips; there was no osteoarthritis in the remaining 3 hips. Our results lead to the conclusion that increased femoral anteversion is a predisposing factor for hip osteoarthritis. This implies that derotational osteotomy in children can be a prophylactic procedure.

Aged↗
PubMed1980

Epidural versus general anaesthesia for total hip arthroplasty in elderly patients.

Sixty elderly patients were given at random either epidural analgesia with bupivacaine 0.75% or general anaesthesia with thiopentone, fentanyl, pancuronium, N2O/O2 for total hip replacement. Preoperatively the patients were of equal physical status with normal and similar laboratory values. All patients were mentally normal for their age. On the 1st postoperative day, the general anaesthesia group had a significantly lower than PaO2 than the epidural group (P less than 0.025). PaO2 in the general anaesthesia group was significantly lower than the preoperative value on the 1st and 3rd days (P less than 0.001 and P less than 0.01, respectively). None of the 29 patients in the epidural group but seven of 31 patients in the general anaesthesia group has significant mental changes postoperatively (P less than 0.01). Five of these patients still had mental changes which reduced the quality of life several months later. In the general anaesthesia group one patient died from acute myocardial infarction. Low postoperative PaO2 might have contributed to this death. Two patients in the epidural group had symptoms of pulmonary embolism postoperatively. Thus elderly patients appear to do better after hip replacement with less deterioration of cerebral and pulmonary functions when given epidural analgesia than when surgery is performed under general anaesthesia. These patients should therefore be offered epidural analgesia whenever possible.

Acid-Base Equilibrium↗
PubMed1976

Giant vesical calculas and anuria.

A 50-year-old fisherman developed uremia and anuria, due to a giant vesical calculus. He was treated with suprapubic lithotomy, and a calculus weighing 1 640 g was removed. This may be the largest calculus ever removed with recovery of the patient. No other reports of giant stones leading to anuria has been found in the available literature. More than 4 years later an inoperable carcinoma of the bladder was discovered. The long delay in diagnosis of the giant stone, as later of the carcinoma, was due to the patient's lack of confidence in doctors and hospitals.

Anuria↗
PubMed1976

Carcinoma of the gastric stump after operation for benign gastroduodenal ulcer.

A series of 36 patients with gastric stump carcinoma is presented. The average time interval between previous operation and diagnosis of carcinoma was 28 1/2 years. The interval was greater with lower age at gastric resection. The stump cancer occurs at the same age, and gives the same symptoms, as gastric carcinoma in general. 17 of the 36 patients were treated by total, or subtotal, gastrectomy. Three patients lived more than 5 years, two of them without recurrence. With surgical treatment of gastroduodenal ulcers in younger patients, more physiological operation methods, such as selective vagotomy, should replace gastric resection, as this would probably reduce the risk of later cancer development. After a time interval of 15 years from gastric resection, all patients should be examined by X-ray and gastroscopy at regular intervals.

Adult↗
PubMedDate not supplied

Leg length inequality measured by ultrasound and clinical methods.

Leg length inequality (LLI) was determined by ultrasound and two clinical methods in 100 subjects without previous disorders of the lower extremities. The mean LLI by ultrasound was 4.1 mm (range: 0-16 mm). An LLI of 10 mm or more was found in 4% of the subjects. The mean inter-observer variation by ultrasound was 0.9 mm (range: divided by 5-8 mm), which was significantly less than that obtained by clinical methods. The 95% confidence interval of inter-observer variation (+/- 2 SD) by ultrasound was +/- 5 mm and this interval is assumed to represent the accuracy of the method. Because LLI measurement by ultrasound is more reliable than clinical methods, ultrasound is recommended for routine use in clinical practice.

Adolescent↗