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10 patients with major instability symptoms due to an acute anterior cruciate ligament injury were operated on with a bone-patellar tendon-bone reconstruction. Tibial condyle bone mineral density (BMD), bone ingrowth and changes in diameter in the tibia bone tunnel were studied with quantified computed tomography (QCT) postoperatively and after 1, 3, 6 and 12 months. We found no sign of bone ingrowth in the form of increased bone mineral density (BMD) in the bone tunnels in any of the patients. The tunnel diameter increased in all patients during the first postoperative months. After 1 year, 5 patients had a smaller diameter than at the first postoperative examination, 2 had the same diameter as immediately after surgery and 2 patients had a larger diameter. A sclerotic zone developed in all patients along the perimeter of the tunnel during the 3-6 months of follow-up. The BMD in the tibial condyle decreased at 3 months; it then increased, but between 6 and 12 months, it levelled out and was slightly lower than postoperatively. In conclusion, we found no growth of bone into the tunnel and tendinous part of the graft during the first postoperative year.

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This study was conducted to determine if bone and muscle loss is reversible in patients who had undergone total hip arthroplasty (THA) owing to necrosis of the femoral head after osteosynthesis for a displaced femoral neck fracture. The cortical bone mineral density (BMD), bone volume, bone mass, and muscle volume of the thigh and the BMD of the distal femur and proximal tibia were measured by quantitative computed tomography in 16 patients. Both extremities were measured just before reoperation. The measurements were repeated 3 and 6 months later. At reoperation, there was a mean 12% relative loss of bone mass and 23% loss of muscle volume in the middle femur on the fractured side compared with the uninjured side. In the distal femur and proximal tibia, there was a relative loss of BMD of 14% and 21% on the fractured side. Six months after reoperation, we found no change in bone mineral at any location on either side. The muscle of the thigh showed a gain in volume of 20% on the reoperated side but no change on the uninjured side. At the time of reoperation, we noted a marked bone and muscle loss on the fractured side. We failed to note any restoration of bone mineral after THA despite remobilization, which is expressed as an increase in muscle volume on the reoperated side. This study indicates that osteopenic bone has difficulties in adapting to patients' improved mobility after reoperation.

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We performed a prospective, longitudinal, quantitative computed tomography (QCT) study of bone mineral density (BMD), cortical bone volume, bone mass and muscle volume in 25 patients who were operated on with osteosynthesis because of a displaced femoral neck fracture. Both legs were scanned within 3 days after the fracture, and 3 and 6 months after the operation. The measurements were performed by a computer tomograph equipped for bone mineral densitometry. We found some side differences among the patients at the time of fracture, but none of the differences was statistically significant. After 6 months, we found reductions in BMD in the distal femur and proximal tibia on the fractured side of 11% and 19%, respectively, as well as a reduction in BMD of 7% in the proximal tibia on the uninjured side. We found no changes in cortical bone mass, either on the fractured femur or on the uninjured femur. The muscles of the thigh showed a loss of 9% on the fractured side, but a gain of 12% on the uninjured side. The findings of a bone loss in the distal femur and proximal tibia of the fractured leg and in the proximal tibia of the healthy leg, but no cortical bone loss in the middle femur on any side 6 months after the fracture, indicate that the cancellous bone is more sensitive to osteopenia. Moreover, this bone loss is interpreted as mainly a posttraumatic effect, since we also found a decrease in bone mineral on the uninjured side, despite a gain in muscle volume on that side, an overuse which was not sufficient to counteract the posttraumatic effect on the bone of the uninjured side.

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The cortical bone mineral density (BMD), bone volume, bone mass and muscle volume of the thigh, and the BMD of the distal femur and proximal tibia were measured quantified by quantitative computed tomography (QCT) after an operation for a displaced femoral neck fracture. Twenty patients were randomized to osteosynthesis or total hip arthroplasty (THA). Both legs were scanned after 18 months, and the operated side was compared with the healthy side. Clinical assessment was performed with a Harris hip score. A reference group of 9 patients, who had undergone THA because of arthrosis, was chosen. In the fracture patients, we found a 9% decrease in bone mass and muscle volume of the middle femur. The BMD of the distal femur and proximal tibia showed a more marked osteopenia. There was no difference in these parameters between the two groups. In the reference group of operated arthrosis patients, we did not find any differences between sides postoperatively. After the operation, the fracture patients had a lower Harris score than the arthrosis patients, and this was most pronounced among those who had undergone osteosynthesis. The finding of a marked osteopenia after a femoral neck fracture, irrespective of treatment, but no bone loss after THA because of arthrosis, implies that patients with a femoral neck fracture are more sensitive to osteopenia, and that the bone loss is not proportional to the operative trauma.

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We investigated the bone mineral density (BMD) of the lumbar vertebrae L1-3 with quantitative computed tomography (QCT) in 18 patients who had been operated on with hip arthroplasty because of unilateral arthrosis. In an earlier prospective study, we did not find any bone mineral changes in the femur or tibia after hip arthroplasty in spite of a large increase of the thigh muscle mass as a sign of a remobilization after the operation. The median BMD had decreased 5.3-8.4 percent in all the measured vertebrae after 6 months postoperatively. Because of the patients' improved walking ability after the operation, this decrease in cancellous vertebral BMD is interpreted as a sign of a post-traumatic osteopenia.

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The cortical bone mineral density (BMD), bone volume, bone mass and muscle volume of the thigh and the cancellous BMD of the distal femur and proximal tibia were quantified by computed tomography (QCT) in 12 patients after hip rearthroplasty due to prosthetic loosening following arthroplasty for arthrosis. Both legs were scanned and the operated side was compared with the healthy side. A control group, 12 patients, had had unilateral hip arthroplasty without subsequent rearthroplasty. There was a 19 percent decrease in bone mass and 13 percent decrease in muscle volume in the middle femur, compared to the contralateral side, in the patients who had undergone rearthroplasty, and a reduction of 9 percent for the same variables in the control group. There was also a more marked osteopenia in the reoperated extremity in the distal femur and proximal tibia compared to the unoperated side.

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We performed a prospective, quantitative computed tomography (QCT) study of bone mineral density (BMD), cortical bone volume, bone mass and muscle volume in 20 patients who were operated on with cemented total hip arthroplasty because of unilateral arthrosis. Both extremities were measured preoperatively, 3 and 6 months after the operation by a single-energy computer tomograph equipped for bone mineral densitometry. Preoperatively, we found a 25 percent decrease in muscle volume of the thigh on the arthrosis side compared to the contralateral side, but only a 6 percent decrease in bone mass, mainly of the cortical bone volume in the middle femur. In the cancellous bone of distal femur and proximal tibia there was a reduction in BMD of 11 and 14 percent, respectively, compared to the contralateral side. After 6 months, we found no changes in cortical bone mass, either on the operated femur or on the contralateral, control femur. The BMD of cancellous bone in distal femur and proximal tibia had not changed. However, the thigh muscle on the operated side showed a strong recovery; 6 months after the operation there was a 19 percent gain on the operated side.

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Measurements of bone mineral content in the calcaneum were made by gamma-absorptiometry in 77 patients with ankle fractures treated by operation, and compared with the calcaneal osteoporosis index. The index was calculated from plain lateral radiographs of the calcaneum. The bone mineral measurements showed a wide range, but there was only a narrow range of the index with exclusively high values. There was a weak correlation between the calcaneal index and the bone mineral content in the injured ankles, but no or only a very poor correlation in the uninjured ankles. We also found no correlation between the decline in index and loss of mineral content in the injured ankles.

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The intercondylar notch diameter was measured in six knees on CT scans before and after anterior cruciate ligament reconstruction. During the operation, direct measurements of the anterior notch diameter was also performed before and after notch plasty. There was good agreement between CT and peroperative measurements, showing that the enlargement of the intercondylar notch can be measured on the CT scan. Twenty-one patients previously reconstructed because of old anterior cruciate ligament injuries were reexamined after a median of 4 years, and their notch diameters were measured by CT or at reoperation. The notch remained open in stable knees, but was narrowed in unstable knees. The notch diameter before notch plasty was assessed with a calliper at operation on 45 patients with acute and 60 patients with old injuries. Both groups had a mean intercondylar diameter of 16 mm. The conclusion that the notch plasty stays open in stable knees emphasizes the importance of this step in the reconstruction procedure.

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220 patients with femoral neck fractures were randomly treated with either a Rydell nail (n 110) or two LIH hook pins (n 110). The age, sex, and displacement patterns were similar in both group. All the patients were operated on by orthopedic specialists and followed clinically and radiographically for 2 years or until death. The mortality at 2 years was similar (28 percent) in both groups. Among 154 survivors, early redisplacement or nonunion was recorded in 19 percent of the Rydell-nailed fractures and 32 percent of the LIH-pinned fractures. In nondisplaced fractures, complications occurred in 8/30 Rydell cases compared with 3/16 in the LIH group. In displaced fractures, complications occurred in 21/48 Rydell cases compared with 28/60 in the LIH group.

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A clinical method is described and claimed to evaluate the active transportation capacity of the luminal epithelium lining the human uterus and fallopian tube. After intracervical application of technetium-labelled human albumin spheres at 1-2 days before ovulation this radioactivity could be followed by gamma-camera when moved in ad ovarian direction. This method is called radionuclide hysterosalpingography (RN-HSG). The results were compared to the findings at normal hysterosalpingography (HSG). By use of this method it was possible to verify active passage in cases of tubal spasm at HSG, lack of transport in cases of normal patent oviducts at HSG as well as presence or absence of active transport through sactosalpinges with or without fimbrial passages to the abdominal cavity as seen at normal HSG. Congruent findings between HSG and RN-HSG was observed in 49%. The studied oviducts were found to be patent with normal HSG but lacked transportation capacity when studied by RN-HSG in 41%. The clinical use of this method is discussed in view of the selection of patients for different forms of in vitro fertilization and egg transfer (IVF-ET).

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Forty-five patients with recent cervical hip fractures were included in a prospective, clinical, radiographic and sequential scintimetric study. Striking changes in radionuclide uptake over the entire hip region on the fracture side were found during the first 5 postoperative months. Fractures that healed without complications showed the highest relative femoral head uptake at 1 week and a peak value at 6 weeks, followed by a gradual decline at the subsequent examinations. Fractures with complications (redisplacement, nonunion, or late segmental collapse) showed a lower initial uptake and a more gradual increase and only a slight tendency towards increased uptake after 3 months. The accuracy in predicting nonunion with scintimetric examination alone is high both at 1 and at 6 weeks, and the accuracy is almost equally high with combined scintimetric, radiographic, and clinical assessment 3-5 months postoperatively.

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Thirty-one femoral neck fractures which united without complications (nonunion or late segmental collapse) were included in a prospective sequential scintimetric study. Roentgenologically, three subgroups with different healing rates could be distinguished: rapid union, normal union, and delayed union. All fractures showed a rapid increase in relative femoral head radionuclide uptake after the 1-week scintimetry, followed by a gradual decline after 6 weeks-3 months. However, both the initial rise in activity and the time for maximal uptake tended to differ between the three groups. For rapid union and normal union the peak activity was registered at 6 weeks and for delayed union at 3 months. It is concluded that sequential scintimetric assessment of femoral head uptake can identify different healing rates and that this difference can be partly explained by a transient impairment of vascular supply to the femoral head in fractures with delayed healing.

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In order to determine the value of scintimetry as a tool for quantitative measurement of femoral head vascularity, the results of postoperative scintigraphic and histologic examination of surgically removed femoral head specimens were compared with those of preoperative radionuclide scintigraphy in 19 failed femoral neck fractures. Following intravenous administration of 600 MBq of Tc-99m MDP before hip replacement, the activity distribution in femoral head sections was recorded with a gamma camera and the area of isotope uptake calculated. A correlation was found between the results of preoperative noninvasive radionuclide scintigraphy and the assessment of isotope uptake in the removed femoral head specimens (r = 0.83, p less than .001) and was confirmed by the results of histologic examination. There is a risk, however, of overestimating the ratio of isotope uptake between the femoral head on the fracture side relative to the contralateral side with respect to quantitative assessment of femoral head vascularity, due to the general increase in isotope owing to accumulation in the injured hip region. The calculations, however, reflect the levels of radionuclide uptake and the varying degrees of femoral head vascularity.

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A scintimetric study using Tc-99m MDP was made of 54 patients with delayed union, nonunion, or late segmental collapse of the femoral head, 4-92 months after femoral neck fracture. In radiographically verified collapse, the radionuclide uptake ratio between the femoral head on the fractured and on the intact side (HHR) was significantly higher than in fractures resulting in delayed union or nonunion. On the basis of scintimetric and radiographic findings, the patients with healing disturbances could be divided into three groups, characterized by the following features: Satisfactory post-reduction position of the fracture without subsequent redisplacement and a high HHR, which as a rule turned out to be delayed union; The same radiographic pattern but with a lower HHR, which in most cases resulted in nonunion; Inadequate reduction or early redisplacement of the fracture with a high HHR, which resulted in nonunion. The fractional precision in discriminating between different types of disturbed fracture healing by means of skeletal scintimetry was 0.86 in this study. This non-invasive and technically simple method would therefore be a valuable complement to radiography in the assessment of healing, more than 4 months after fracture of the femoral neck.

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Twenty-six patients with late complications following femoral neck fracture were examined with both skeletal and bone marrow radionuclide scintimetry. There was no correlation between the methods with respect to the quantitative assessment of femoral head vascularity based on different uptake ratios comparing the fractured and the intact side. Skeletal scintimetry always had good image quality and permitted reliable differentiation between nonunion of the fracture and late segmental collapse, in contrast to bone marrow scintimetry which gave poor image quality. Skeletal scintimetry thus seems superior to bone marrow scintimetry for assessment and differential diagnosis of late complications following femoral neck fracture. It is emphasized that the physiological mechanisms for radionuclide uptake must be taken into account when comparing scintimetric studies using different tracers.

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Lung perfusion was studied in 10 patients (mean age 58 yr) in the lateral position during enflurane anesthesia. They were ventilated through a double-lumen endotracheal catheter: 1) by one ventilator with free distribution of ventilation between the lungs, with no (zero) end-respiratory pressure (ZEEP); 2) as above but with a general positive end-expiratory pressure (PEEP) of 9 cmH2O; or 3) by two ventilators with equal distribution of ventilation between the lungs and with a selective PEEP of 8 cmH2O to the dependent lung only. Total ventilation was on average 8 l/min (BTPS) throughout the study. During the first method, 34% of ventilation was distributed to the dependent and 66% to the nondependent lung. Cardiac output (thermodilution) was 4.5 l/min, 57% being distributed to the dependent lung as assessed by iv boli of Xenon 133. During the second method, ventilation was assumed to be distributed equally between the lungs. Cardiac output was decreased to 3.8 l/min, and the dependent lung received 81% of lung blood flow. During the third method, cardiac output was significantly greater than during the second method (4.1 l/min), 51% passing to the dependent lung. Peak and end-inspiratory airway pressures were 5-18 cm H2O lower during selective than during general PEEP. Arterial oxygen tension was significantly greater during the third method than during either of the other ventilator settings and the alveolar-arterial oxygen tension difference was almost halved compared with the first method. It is concluded that differential ventilation with selective PEEP improves ventilation-perfusion matching and thus oxygenation.

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99mTc-Plasmin scintigraphy of suspected vein thrombosis registered by a gamma camera was compared with phlebography. The results indicate that the plasmin test can be an alternative method to phlebography. The plasmin test registered by a gamma camera has a high sensitivity but relatively low specificity; this agrees with the results of previous investigations regarding registration with a single detector.

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The effects of Harrington instrumentation on the longitudinal axis rotation of the vertebra, the kyphosis-lordosis, and the rib-cage deformity were investigated by computer tomography in 33 patients. No significant derotation was achieved. The sagittal diameter of the rib cage was reduced significantly with distraction rod instrumentation and further by additional application of a compression rod. The rib hump was reduced significantly only with distraction rod instrumentation. The obtained results indicate that despite instrumentation, the spine preserves an almost unchanged peripheral position in the rib cage.

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