Biomedical subjects

E Karaharju

Publications and source records attributed to E Karaharju.

At least 19 recordsLinked to original sources

PubMed1992

Treatment of solitary plasmacytoma of the femur. A case report.

In radical tumour surgery the inevitable bone loss is considerable. If in addition the local tissues at the tumour site have been damaged by radiation therapy, massive endoprosthesis or even amputation should be considered. In cases with large bone loss, a vascularized fibular graft is one possibility to bridge the resected region. A case of a young man with a solitary plasmacytoma of the upper femoral diaphysis is presented. The lesion was reoperated 3 years after the primary diagnosis with resection of the non-ossified tumour site and reconstruction with a vascularized fibular graft.

Adult↗

PubMed1990

Collagen synthesis and mineralization in the early phase of distraction bone healing.

Corticotomy of the distal radius followed by gradual distraction by external fixation was performed on three sheep. Collagen synthesis and mineral deposition were analysed from sequential biopsies obtained from the center of the distraction area during the first 4 weeks of distraction. The whole distraction area was rapidly filled with organic matrix the amount of which, due to fluctuation in its nonprotein component, initially decreased from 88 to 66% of the level in control bone but gained its initial level in 4 weeks. Total protein in the matrix represented 70% of that in the control bone during the 4-week follow up period while the proportion of collagen of the total protein increased from 53 to 88%, a level comparable with the unoperated bone. Determination of the type of fibrillar collagen by characterization of their cyanogen bromide peptides showed that in the distraction area production of type II collagen does not occur but the heteropolymer type I (alpha 1(I)2 alpha 2(I)1) collagen represents almost totally the collagen synthesized. Deposition of mineral into the distraction gap was detectable already after 2 weeks and increased rapidly after 3 weeks of distraction. The results suggest that unlike in other processes, e.g., direct osteonal and callus-type bone repair, in distraction bone healing gradual distraction of osteotomized bone leads directly to synthesis of mature fibrous organic matrix of bone followed by its rapid mineralization.

Animals↗

PubMed1990

Ten years' experience in patients with osteogenic sarcoma in Finland.

Ten years' results of 56 patients with high grade osteogenic sarcoma are reported. Fifty-two patients had M0 disease. Immediately after open biopsy the patients were treated with chemotherapy using modified Rosen's protocols T4, T7 and T10. The primary tumor was adequately removed in most patients. Six children were treated with limb saving. The actuarial and disease-free survival was 80% after 1 year, and 73% to 8 years. Two patients died because of toxic side effects of chemotherapy, one of septicemia, the other of late cardiac failure secondary to doxorubicin.

Actuarial Analysis↗

PubMed1989

External fixation of Colles' fracture.

Radiographic and functional results of external fixation of 32 Colles' fractures were compared with the results of plaster fixation of 189 Colles' fractures. Despite the fact that the fractures treated with the external device were more unstable and comminuted, the final results were equal in both groups, and the radiographic outcome of external fixation was superior. Pin loosening decreased with predrilling rather than self-tapping. We recommend external fixation for unstable fractures of the distal forearm.

Adolescent↗

PubMed1988

Heavy drinking and accidents--a prospective study among men of working age.

The injuries of 438 consecutive men of working age (20-64 years) were investigated. These patients were admitted to the Department of Orthopaedics and Traumatology of the Helsinki University Central Hospital. The MAST interview was used as the criterion for heavy drinking. Of the whole series 27.4 per cent met the heavy drinking criterion and in 36.4 per cent alcohol intoxication (AI) was present on admission. AI was more common in heavy drinkers (62 per cent) compared with the controls (23 per cent) (chi 2 test, P less than 0.001). S-GGT was elevated in 34 per cent of the heavy drinkers. Elevated levels of S-GGT among heavy drinkers also correlated with postoperative complications. The hospital stay of the heavy drinkers compared with the controls was statistically significantly longer (10.7 days versus 7.3 days). Although the proportion of alcohol intoxication among heavy drinkers was high, of the heavy drinkers almost 40 per cent were sober on admission. Interviews, such as MAST are recommended for use routinely with injured patients to assess alcohol abuse 'through accidents'.

Accidents↗

PubMed1987

Chordoma with a massive spindle-cell sarcomatous transformation. A light- and electron-microscopic and immunohistological study.

A 26-year-old woman was operated on for a bulky tumor in the sacral region; she died of massive local tumor recurrence and pulmonary metastases 3 months later. Most of the original tumor showed a highly cellular spindle-cell sarcoma compatible with a fibrosarcoma of a high grade of malignancy. In a few small areas of the tumor, a chordoma-like pattern surrounded by growth of spindle-cell sarcoma was found. The spindle-cell component exhibited vimentin positivity in all tumor cells, but many cells were also cytokeratin-positive. The chordoma-like areas showed cytokeratin in all tumor cells. The chordoma-like areas, but not the spindle-cell areas also were positive for epithelial membrane antigen and S-100 protein. This case indicates that the sarcomatous change associated with chordoma may contain keratins as a sign of epithelial differentiation, and may thus represent sarcomatous transformation of chordoma cells, rather than a coincidental soft-tissue sarcoma or collision tumor.

Adult↗

PubMed1985

Immunohistochemical demonstration of nociceptors in the ligamentous structures of the lumbar spine.

Substance P, a physiologically potent neuropeptide is known to participate in the sensory, and especially nociceptive, transmission of neural impulses. On histologic grounds, the nerve terminals of the sinuvertebral nerve formerly have been suggested to be sensory in character and to mediate the low-back pain syndrome. Samples of paramedullary ligamentous structures were collected on disc operations. A positive immunoreaction as an indicator of substance P was confirmed in some nerve terminals of the posterior longitudinal ligament. Neither the yellow ligament nor the intervertebral disc showed such nociceptive-type nerves.

Humans↗

PubMed1985

Innervation of synovial membrane and meniscus.

Substance P-immunofluorescent nerves, which are closely connected to pain transmission, were shown in human knee synovial membrane and menisci. Both tissues also contained enkephalin-immunofluorescent nerves, which are probably involved in the modulation of pain transmission. Previous suggestions on the presence of nociceptive receptors in these non-cartilaginous joint structures, made on a histological basis, are thus confirmed by a specific immunohistochemical method.

Enkephalins↗

PubMed1979

The healing of experimental fractures by compression osteosynthesis. I. Torsional strength.

Biomechanical properties of osteotomized rabbit tibio-fibular bones fixed with 6-hole stainless steel AO/DCP plates were investigated with torsional loading 3 to 24 weeks postoperatively. During the first 9 weeks maximum torque capacity, energy absorption and torsional rigidity increased, reflecting progressive bony union between the fractured bone ends. From 9 to 24 weeks the values of torque capacity and energy absorption decreased, whereas torsional rigidity seemed to reach a steady state without further significant changes. For the three parameters considered, the mean percentage differences between the osteotomized plated bones and their paired-sham-operated controls were 69, 64 and 80 per cent, respectively. The results suggest that internal fixation of fractured bones provides conditions for undisturbed fracture healing, but that subsequently the rigid nature of the implant has an adverse effect on the cortical bone, which slowly loses strength. Thus the optimal time for removal of the plate seems to be shortly after the fracture has healed and before the bony tissue had been weakened by secondary changes, such as cancellous transformation and spatial rearrangement of the tubular bone.

Animals↗

PubMed1979

The healing of experimental fractures by compression osteosynthesis. II. Morphometric and chemical analysis.

The effects of rigid plate fixation on the structure and chemical composition of bones during healing of experimental fractures were studied by morphometric and chemical analysis at intervals of 3 to 24 weeks after attachment of six-hole AO plates to osteotomized rabbit tibiae. After fracture union gradual porotic transformation could be observed from 9 weeks onwards, with rapid excavation and breakdown of the cortical wall. During the study over 24 weeks the degree of porosity increased from 9.0 +/- 4.8 per cent to 37.5 +/- 10.2 per cent (P less than 0.001). This osteoporosis was accompanied by formation of new subperiosteal bone. The changes in the tubular bone led to a progressive increase in overall diameter and in the area occupied by the medullary cavity throughout the experiment. In the osteotomy area increased values were found for the content of hexosamines and the ratio of hexosamines to hydroxyproline at 3 weeks, indicating formation of connective tissue in the fracture area. Later on, no chemical signs of callus formation could be detected. In spite of the slight increase in the content by hydroxyproline, reflecting the formation of new bone subperiosteally, the chemical composition of the unresorbed cortical bone remained unchanged.

Animals↗

PubMed1979

Fractures of the proximal femur in Finland in 1975.

Hospital admissions due to fractures of the proximal femur in Finland increased 50% between 1968 and 1976. In this study the established differences and results of treatment in regional and district hospitals are reviewed. From the mortality incidence and the length of hospitalisation, the results were better in regional than in district hospitals, and better for operatively than for conservatively treated patients. Of the different operative methods, the best primary results were obtained with endoprosthetic replacement and osteosynthesis with a fixed-angle nail plate.

Adult↗

PubMed1978

Radiographic abnormalities in tubular bone after rigid plate fixation in rabbits.

Rigid stainless steel osteosynthesis plates (DCP/ASIF) were attached bilaterally onto the intact tibio-fibular bone in 40 rabbits. Axial compression was used on the right side, neutral plate fixation on the left. The radiographic appearances of the bone were analysed 1 day, and 1, 3, 12, 24 and 36 weeks postoperatively. The changes in the bone were progressive, related to the time of fixation, and similar in the right and left leg. The main alterations were a progressive thinning of the cortical bone under the plate and a progressive cancellous transformation of the tubular bone.

Animals↗

PubMed1978

Changes in calcium and hydroxyproline content of cortical bone after compression and neutral plate fixation.

Calcium and hydroxyproline content of intact rabbit tibio-fibular bone was assay chemically 1 day to 36 weeks after compression and neutral plate fixation with a 4-hole stainless steel ASIF/DCP plate. During the first three postoperative weeks calcium content of the cortical bone decreased by an almost significant amount (P less than 0.05); thereafter, calcium values remained subnormal but did not differ significantly from initial postoperative values. Hydroxyproline content increased steadily throughout the experiment (P less than 0.001). The changes in chemical composition of the bone were of the same magnitude after compression and neutral plate fixation. The results suggest that the cancellous transformation of cortical bone, known to take place under rigid plates, reflects an active remodelling process of the bone in which the calcium and hydroxyproline content changes only slightly.

Animals↗

PubMed1978

Studies on mechanical strength of bone. II. Torsional strength of cortial bone after rigid plate fixation with and without compression.

Biomechanical properties of intact rabbit tibio-fibulae were investigated with torional loading 1 day to 36 weeks after fixation using 4-hole stainless steel ASIF/DCP plates with and without compression. During the first 12 weeks energy absorption and torque moment increased slightly as a result of subperiosteal new bone formation following application of the plates. There was a concomitant increase in the yielding properties of the bone, reflecting progressive porotic transformation. Thereafter, up to 36 weeks postoperatively, the values for energy absorption, torque moment and angular deformation gradually declined in both groups of bones. The differences between normal control bones and plated bones at 36 weeks were 70.1, 53.0 and 26.3 per cent, respectively. The decay of torsional strength was the same whether or not compression was used in the plate fixation. The results suggest that even in normal bone rigid plates induce a considerable loss of strength due to the cancellous transformation they are known to cause in cortical bone.

Animals↗

PubMed1978

Structural changes in intact tubular bone after application of rigid plates with and without compression.

The influence of a rigid plate on the structure of intact tubular bone was studied in forty adult rabbits using a four-hole commercial-steel DCP-ASIF plate attached to each tibiofibular bone, with and without compression. The morphological changes in the bone underlying the plate were examined and were assessed quantitatively at one day to thirty-six weeks after operation. The rigid plate induced porotic changes in the cortical bone, which were evident three weeks after the operation and increased rapidly between twelve and eighteen weeks. At thirty-six weeks, resorption cavities occupied 40.6 per cent of the cortical wall of the bones plated with compression and 41.2 per cent of the wall of those plated without compression. The changes were visible slightly earlier in the presence of compression. A rigid plate brought about a statistically significant increase both in the outer diameter of the bone and in the diameter of the medullary space as a result of subperiosteal new-bone formation and concomitant subendosteal bone resorption.

Animals↗

PubMed1978

Effect of rigid plate fixation on structure and mineral content of cortical bone.

The effect of rigid plate fixation on the structure and mineral content of cortical bone were studied by light and fluorescence microscopy and by chemical analysis of calcium and hydroxyproline content in 27 rabbits from one day to 17 weeks after the attachment of a 5 hole ASIF-plate onto intact femur. Between the second and seventeenth postoperative weeks the plated cortical bone became progressively thinner and porotically transformed. Subendosteal resorption was partly offset by the formation of new subperiosteal bone that resulted in a slightly wider than normal, thin-walled tubular bone. At 17 weeks the mean calcium content of the tubular bone under the plate was 15% less than the initial postoperative content (p less than 0.05). The corresponding decrease in calcium content in the metaphyseal and epiphyseal areas of both the operated and the control bone was highly significant. The mean values for hydroxyproline in plated and control bones remained largely unchanged.

Animals↗

PubMed1977

Catecholamines in shock.

The role of endogenous catecholamines in various clinical shock and stress states is reviewed; the effects, especially on the peripheral circulation, of catecholamine secretion are the same independent of the cause. Risks of using sympathomimetic agents in the treatment of shock are evaluated. A prolonged noradrenaline activity is to be expected in surgical stress states, e.g. multiple injuries, fat embolism syndrome, burns and infections; therapeutic approaches to minimize the sympathoadrenal activity are outlined.

Catecholamines↗

PubMed1976

[Serum enzymes in seriously injured patients].

In 45 patients with multiple injuries due to trauma, admitted consecutively to our clinic, the following enzyme activities were studied, beginning at the onset of treatment: SDH, GPT, GLDH, and acid phosphatase. The mean levels of SDH rose in all patients between 2 and 24 h after trauma. The mean values of GPT were above normal between 2 and 48 h after trauma; this rise was more pronounced and statistically significant in those patients who eventually died of trauma than in the less severely injured ones. Twenty-four hours after trauma, the levels of GLDH were 16 times higher in the first group of patients than in the less severely injured group. These results lead us to the conclusion that through serum level measurements of these enzymes particularly of GPT it is possible to evaluate the degree of tissue damage and the general state of this group of patients.

Acid Phosphatase↗