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Biomedical subjects

E O Karaharju

Publications and source records attributed to E O Karaharju.

At least 19 recordsLinked to original sources

Platelet-derived growth factor and vascular endothelial growth factor expression in disc herniation tissue: and immunohistochemical study.

Angiogenesis is essential in tissue growth and regeneration. There are several factors that are able to stimulate vascular endothelial cell growth, including platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF). Disc herniation tissue (DHT) contains vascular ingrowth, which promotes granulation tissue formation. In this study we observed 50 disc herniations for PDGF and VEGF immunoreactivity. PDGF immunopositivity was detected in 38 samples (78%). In 28 samples (56%) there were PDGF immunopositive capillaries, PDGF immunopositive disc cells were detected in 19 samples (38%) and PDGF immunopositive fibroblasts in 6 DHT samples (12%). VEGF immunopositive capillaries were identified in 44 DHT samples (88%). For neither growth factor was immunopositivity dependent on preoperative radicular pain duration. In extrusions (n = 25) VEGF immunopositive capillaries were detected in 23 samples (92%) and PDGF immunopositivity in 21 samples (84%). PDGF immunopositivity was more commonly associated with capillaries than with nuclei of disc cells. In sequesters (n = 20) VEGF immunopositive capillaries were identified in all samples and PDGF immunopositivity in 16 (80%). As in extrusions, PDGF immunoreaction was more prevalent in capillaries than in disc cells. Patient age did not relate to VEGF expression. In all age groups it was higher than 80%. Thus capillaries in disc herniation tissue are evidently newly formed and our results demonstrate that PDGF and VEGF participate in the neovascularization process. The presence of PDGF in fibroblasts and in disc cells suggests that this growth factor regulates the function of these cells, possibly the proliferation of the cells and the production of extracellular matrix components.

Adult↗

A controlled immunohistochemical study of inflammatory cells in disc herniation tissue.

STUDY DESIGN: The presence and abundance of inflammatory cells was studied immunocytochemically in lumbar disc herniations (DH) and macroscopically normal discs for comparison. OBJECTIVES: The objective of the study was to characterize inflammatory cells that appear in herniated disc tissue and to study the relative abundance of various types of inflammatory cells. SUMMARY OF BACKGROUND DATA: Only few macrophages were observed in control discs, whereas abundant macrophages were present in half of the DH. Other types of inflammatory cells were less often abundant in the present material. In about a third of the DH interleukin-1 beta-expressing cells were also observed. METHODS: Twenty-four DH and control tissue from five discs were studied immunocytochemically, using specific monoclonal antibodies to various types of inflammatory cells and interleukin-1 beta. The results were compared with corresponding clinical data. Macrophages were studied with an antibody to CD68 antigen and Ber-MAC3 antibody separately. RESULTS: The obtained results suggest a variable inflammatory cell response in DH, which seems to be often dominated by macrophages at the time of operation. Thus previous suggestions of sometimes very active inflammation in DH tissue are supported. CONCLUSIONS: Inflammation may be important in disc tissue pathophysiology, possibly also in discogenic pain mechanisms.

Adult↗

Concomitant immunocytochemical study of macrophage cells and blood vessels in disc herniation tissue.

Twenty disc herniations (DH) were studied immunocytochemically for macrophages and blood vessels. Serial thin frozen sections were immunostained with an antibody specific for tissue macrophages (monoclonal antibody to CD68 antigen) and the endothelium of blood vessels (polyclonal antibody to von Willebrand factor). With this method, blood vessels, often abundant, were observed in as many as 16/20 (80%) of the DH studied, 12 disc extrusions and 8 sequestrated discs, whereas abundant macrophages were noted in 11/20 (55%) of the DH. Macrophages were present only in areas with blood vessels and had presumably infiltrated the tissue from them. As has been noted previously, some blood vessels are apparently newly formed as a result of tissue injury, whereas others were present in the disc prior to herniation. This is suggested by the lack of a clear correlation between the presence or absence of blood vessels and the preoperative duration of radicular pain. In areas of the DH where cartilage fragments occurred, both macrophages and blood vessels were particularly abundant.

Adult↗

Relationship of the Pain Disability Index (PDI) and the Oswestry Disability Questionnaire (ODQ) with three dynamic physical tests in a group of patients with chronic low-back and leg pain.

OBJECTIVE: To determine the relationship between overall disability in daily activities, assessed with the Pain Disability Index (PDI) and the Oswestry Disability Questionnaire (ODQ), and impaired performance on three physical tests in patients with chronic low-back pain. DESIGN AND SUBJECTS: The PDI and ODQ were administered in a cross-sectional study, before beginning a back rehabilitation program, to 45 patients with low-back pain of > or = 3 months' duration, with or without radiation to the legs. All patients also performed repetitive sit-up, arch-up, and squatting tests. SETTING: Tertiary care center. RESULTS: Modestly significant (p < 0.05) or significant (p < 0.01) inverse correlations (Pearson's r = 0.30-0.41) were noted between the PDI and the ODQ and all three physical performance tests. When normative data were used, the correlation (Spearman's rs = -0.45) between PDI and the squatting test remained significant (p < 0.01), whereas it was modestly significant (rs = -0.33, p < 0.05) between the ODQ and squatting test and between the PDI and arch-up test (rs = -0.35, p < 0.05). Compared with patients presently working, those on sick leave had significantly higher scores on the PDI and ODQ (Wilcoxon's two-sample test: p < 0.001) and also significantly worse performance on all physical tests (p < 0.001). CONCLUSIONS: The PDI and ODQ, as measures of self-perceived disability, and impaired performance on repetitive squatting, arch-up, and sit-up tests, as measures of physical capability, show some overlap in low-back-pain patients. Both types of disability measures are clearly influenced by the patient's work status.

Adult↗

Early bone matrix formation during distraction. A biochemical study in sheep.

Osteotomy of the distal radius and gradual distraction were performed on 20 sheep. Bone matrix synthesized between the osteotomized bone ends was biochemically characterized at 3, 5, 7, and 14 days after the start of distraction. The deposition of mineral was negligible during the 14-day period. No change was observed in the amount of organic matrix, which comprised 15 +/- 1.4 percent of the wet weight of the tissue. The amount of total protein of the wet weight in the matrix increased from 4.6 to 7.6 percent between 5 and 7 days of distraction. During the first 7 days, the nonprotein component decreased from 11 to 7.3 percent. The proportion of collagen of the total matrix protein increased gradually from 29 to 59 percent. In view of the patterns of the cyanogen bromide peptides of the matrix proteins, the heteropolymer type I[1(I)2(2)(I)1] collagen was consisted to be the principle fibrillar collagen synthesized in the distraction gap. The results suggest that tension-stress markedly affects the synthesis of fibrillar collagen towards the formation of mature bone matrix. In this process, a preliminary lag phase probably exists during which the capacity for protein synthesis is low while the synthesis of Type I collagen has started. In the secondary phase an augmented synthesis of Type I collagen takes place.

Animals↗

Intercorrelation and test-retest reliability of the Pain Disability Index (PDI) and the Oswestry Disability Questionnaire (ODQ) and their correlation with pain intensity in low back pain patients.

OBJECTIVE: To determine the intercorrelation between subjective disability, as assessed with the Pain Disability Index (PDI) and the Oswestry Disability Questionnaire (ODQ) and their correlation with visual analogue scale (VAS) pain intensity ratings. DESIGN AND SUBJECTS: Questionnaires were administered to 94 patients with chronic low back pain with or without radiation into the legs of at least 3 months' duration. SETTING: Tertiary care center. RESULTS: High correlations were noted between the ODQ and PDI (r = 0.83) and PDI factor 1 (r = 0.84), a subscale of the PDI. Lower correlations were noted between pain intensity (VAS) scores and the ODQ (r = 0.62) and the PDI (r = 0.69). A weaker correlation (r = 0.41) was noted between the ODQ and PDI factor 2. Intraclass correlation coefficients (ICC) for test-retest reliability in 20 patients (time interval 1 week) were for the ODQ ICC = 0.83, PDI ICC = 0.91, PDI percentage score ICC = 0.91, PDI factor 1 ICC = 0.87, and PDI factor 2 ICC = 0.73, respectively. CONCLUSIONS: The present results suggest that either the PDI or the percentage score PDI and also the even shorter-to-administer PDI factor 1 may be useful and reliable tests for the assessment of subjective disability in low back pain patients. As noted by the moderate intercorrelations with pain intensity scores, both the PDI and the ODQ address a broader concept of disability than that directly related to pain intensity.

Adolescent↗

Distraction bone healing.

Bone formation by distraction was studied using three different experimental models: (1) Physeal distraction of the sheep radius was performed in 20 animals. (2) Distraction after osteotomy of the radius was carried out in 39 sheep. (3) Mandibular distraction after osteotomy was performed in 17 sheep. Formation of the organic matrix and osteogenesis were studied by radiographic, histologic, and biochemical methods as well as by electron microscopy. The mode of osteogenesis was essentially similar in all of these distraction models. Bone formation was preceded by organization of the collagenous matrix in the distraction area. In the beginning of the distraction, the gap was composed of a heterogeneous cell population, with large polymorphic fibroblast-like cells. The cells in the central part differentiated into fibroblasts, which remained functionally active as long as distraction proceeded. During physeal distraction, bone formed from the epiphyseal and metaphyseal sides as well as from the surrounding perichondrium. Also, in osteotomy distraction of both tubular bone and mandible, bone formed centripetally from the osteotomized bone ends toward the center of the gap. The organic matrix was composed almost solely of Type I collagen in the earliest stages, suggesting that the mode of osteogenesis differs from bone repair by fracture callus. The structure of the distracted segment was mainly lamellar trabecular. Corticalization of the lengthened bone segment occurred gradually after several months.

Animals↗

Surgical treatment of myeloma of bone.

33 patients treated operatively for plasma cell disease were analysed. There were 21 men and 12 women with an average age of 54 years. There was an undefined bone tumour in 23 cases, and a pathologic fracture in 10 cases. In only 6 cases was the diagnosis known before the operation. The primary tumour localisations were: vertebral column in 13, pelvis in 7, femur in 6, humerus in 2, rib in 1, tibia in 1, fibula in 1, scapula in 1 and olecranon in 1 case. 16 diagnostic biopsies were taken. Vertebral tumours were mainly evacuated or decompressed, combined with a stabilising procedure in 8 cases. A total of six endoprostheses, five to the femur and one to the humerus were performed. Two primarily wide resections, to the fibula and to the scapula were done. There were no locally recurring tumours during a mean follow-up time of 4 years and 2 months, and we conclude that operative and oncologic treatment is successful in providing the patient with a stable, pain-free locomotive system.

Adult↗

Distraction osteogenesis of the mandible. An experimental study on sheep.

Distraction bone healing has been studied in long bones but there are only few experiments reported in relation to the mandible. The histological pattern of the healing process after mandibular distraction is described. After osteotomy the mandibles of 17 growing sheep were lengthened by gradual distraction using an external fixation device. The follow-up varied from 0 to 52 weeks. The results indicate that bone healing in mandibles is principally the same as in long bones. Four phases can be observed during the repair process: 1) formation of collagen aligned in the direction of distraction, 2) bone formation over the collagen template, 3) bone union across the distraction gap, and 4) remodelling of the lengthened segment. Some increased osteoblast activity was also seen in the control side.

Animals↗

Bone formation after distraction osteotomy of the radius in sheep.

Gradual distraction by external fixation was performed one week after osteotomy of the radius in 12 sheep. Bone regeneration in the distraction area was studied by light and electron microscopy. One week after starting the distraction the gap was composed of hematopoietic cells and fibroblasts. The collagen production had already started and it continued actively throughout the distraction period. The collagen produced by the fibroblasts in the central interzone of the gap was organized according to the direction of the distraction. The osteoblasts were lined up along the collagen bundles and osteoid formation was most active around the capillaries. Mineralization started two weeks after the beginning of the distraction. After cessation of the distraction, separate groups of cartilaginous cells were found in some specimens among the newly formed bone. Our findings suggest that osteogenesis as a result of gradual distraction occurs through the whole distraction area with preceding formation of organized collagen matrix. The bone structure in the distracted segment represents an organized lamellar structure at an early stage of the osteogenesis.

Animals↗

Metastatic fractures of long bones.

Forty-two patients with a total of 52 metastatic fractures of long bones were analysed retrospectively with regard to the type of treatment, complications, general mobility and survival. Endoprosthetic replacement appeared to be better than osteosynthesis in the proximal femur, and this method should also be considered in pathological fractures of the distal femur. Nailing is indicated in fractures of the shafts of long bones in the lower limb, and also in the humerus. Osteosynthesis with a plate has only limited indications. Cement should be added to an osteosynthesis or replacement of a pathological fracture in order to achieve immediate stability. On the whole, the life expectancy of these patients has improved; five in our series lived for more than 6 years after the treatment of their metastases. The method of surgical treatment therefore needs more consideration.

Bone Neoplasms↗

Mandibular distraction. An experimental study on sheep.

In a series of 17 growing sheep (aged 13.5-19 weeks) the recently developed external fixation frame permitting gradual distraction, was tested. The frame gives good stability during distraction. Mandibular osteotomy was performed transversely in the middle of the ramus, under general anaesthesia, with an oscillating saw. Using distraction by approximately 1 mm per day, lengthening of the mandibular ramus was achieved. X-ray analysis showed all the distracted osteotomies to have healed in 25 days, showing new bone formation in the distraction gap. The pattern of radiological healing was graded according to the phase of consolidation. With this method it appears to be possible to lengthen the mandible without transplantation of additional bone.

Animals↗

[Cysts of the calcaneus, diagnosis and treatment].

Cystic lesions of the calcaneus are almost always benign solitary bone cysts. They are in most cases asymptomatic; the need for surgery being diagnostic. The purpose with this study was to precisize the indications for surgical treatment of these lesions. We analyzed 11 cases of cystic lesions of the calcaneus. Two patients had atypical radiographs, four had symptoms and in 7 patients the lesion was found accidentally. Five patients underwent surgery. The histological findings in three cases with typical radiographs was solitary bone cyst and in the two cases with atypical radiographs respectively chondromyxoid fibroma and fibrous dysplasia. We made a solitary observation of raised intracystal pressure in one symptomatic patient with a solitary bone cyst. Asymptomatic cystic lesions of the calcaneus can safely be treated by simple observation if they fill the criterias for a typical solitary bone cyst of the calcaneus. Atypical cysts should be biopsied. Persisting pain is also an indication for surgery. Elevated intracystal pressure can contribute in the pathophysiological mechanisms producing pain.

Adolescent↗

Allogeneic grafts for bone tumor. 21 cases of osteoarticular and segmental grafts.

We treated 21 aggressive and malignant bone tumors by wide resection and replacement with deep-frozen osteoarticular and segmental (intercalary and block) allografts. Radiologic and histologic studies showed a gradual accretion of new bone on the graft trabeculae, sometimes with total creeping substitution. Substantial resorption of grafted condylar bone occurred in 3 of 14 cases. One of them ended with arthrodesis; in the other 2 the result after augmentation autografts was fair. Radiographically, a gradual joint surface destruction was observed in all the osteoarticular grafts after 5 years, not correlating with joint function, however. Biopsies showed some cartilage regeneration. Each patient underwent, on an average, two operations. Function after osteoarticular grafts at 3-16 years was excellent in 1 case, good in 4, fair in 6, and poor in 1 case; 2 cases were too recent for evaluation. Function 3-12 years after segmental grafts was excellent in 3 cases and poor in 3 cases (1 amputation due to nonunion, 1 amputation due to recurrence, and 1 prosthetic replacement due to recurrence); 1 case was too recent for evaluation. We conclude that an allograft is an acceptable alternative in the reconstruction of large tumor defects. However, it still presents unsolved immunologic and preservation problems, which make the prognosis guarded.

Adolescent↗

Functional recovery after fractures of the distal forearm. Analysis of radiographic and other factors affecting the outcome.

Functional recovery of the wrist and hand after a fracture of the distal forearm in 207 consecutive patients was analysed. A good or excellent result was achieved in 77 percent, fair in 22.5 percent and poor in 0.5 percent of cases. The result in 14 unstable fractures treated with external fixation was as good as that of the whole series. Good functional results were associated with extra-articular fractures, good anatomical results, male sex and low age. Comminuted intra-articular fractures of the radiocarpal joint, fracture line into the distal radio-ulnar joint, fracture of the ulnar styloid and a poor anatomical result in addition to high age contributed to a poor result.

Adolescent↗

Hemijoint allografts in the treatment of low grade malignant and aggressive bone tumours about the knee.

Nine consecutive patients undergoing osteoarticular allogenic transplantation for low grade malignant or aggressively benign tumours have been followed up for between 8 to 15 years. Eight patients had functioning knees whilst 1 ended in arthrodesis. Of the functioning knees all had full extension but only 3 could flex more than 90 degrees. Seven patients had returned to work. Radiologically all the knees showed progressive deterioration. In spite of this only three knees were painful with exercise and none at rest. We conclude that hemijoint allografts represent a useful alternative to make good a bony defect after tumour resection about the knee, but that the ultimate result of such a reconstruction depends on survival of the joint surfaces.

Adolescent↗

[External fixation in open fractures of leg. Analysis of traps and complications of the method].

A consecutive series of 51 compound tibial fractures treated by external fixation have been reviewed. All the cases whose progress was marred by complications were analysed separately. From this analysis, the following conclusions have been reached: 1. A gap at the fracture site, due to loss of bone substance or to distraction of the fragments should be treated as soon as possible by bone grafts. 2. Inadequate reduction should be corrected at the time of primary treatment. 3. Pins inserted into the region of the fracture should be repositioned early to prevent infection along the pin tracks. 4. If a sequestrum is evident, it is often necessary to remove such a focus of infection. 5. Weight-bearing, whenever feasible, should be started as soon as possible. A patellar-tendon-bearing orthosis or unilateral semi-elastic external fixation are possible satisfactory solutions in this respect. 6. When the fracture site is infected and contains necrotic fragments, the superiority of external fixation over internal fixation is obvious. The method makes it possible to stabilise the fragments without interfering with local healing and allows the exposed bone to be covered in a stable environment. Because of this analysis of the complications and pitfalls of external fixation, we have been able to put forward a regimen of treatment that may improve results.

Adult↗