Biomedical subjects

K von Sivers

Publications and source records attributed to K von Sivers.

7 recordsLinked to original sources

PubMed1997

Bone and muscle mass after femoral neck fracture. A controlled quantitative computed tomography study of osteosynthesis versus primary total hip arthroplasty.

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.

Aged↗

PubMed1997

Decrease in bone mineral density and muscle mass after femoral neck fracture. A quantitative computed tomography study in 25 patients.

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.

Bone Density↗

PubMed1994

Decrease in vertebral bone density after hip arthroplasty. A quantitative computed tomography study in 18 arthrosis cases.

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.

Aged↗

PubMed1993

Bone and muscle mass after hip rearthroplasty. Controlled CT study of 12 patients.

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.

Aged↗

PubMed1993

Bone and muscle mass after hip arthroplasty. A quantitative computed tomography study in 20 arthrosis cases.

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.

Aged↗

PubMed1989

Prediction of instability of Colles' fractures.

The tendency of 267 consecutive Colles' fractures to dislocate during plaster-cast treatment was correlated with several parameters measured from the initial radiographs. Stepwise logistic regression analysis showed that radial axial shortening had the greatest prognostic power. The age of the patient and Lidström's class provided additional prognostic information. Initial radial axial shortening of 5 mm or more generally indicated an unfavorable anatomic end result.

Adult↗

PubMed1988

Late displacement of Colles' fractures.

A prospective radiological study was performed on 170 Colles' fractures which were reduced and treated in plaster. Twenty-nine fractures, which displaced and which needed a further reduction and external fixation, were excluded. The mean length of the radius decreased during plaster treatment to the same position as before the initial reduction. Radial angular compression also increased significantly during treatment. Among the seventeen fractures which were malunited, twelve had definitely displaced after the 11th day.

Adult↗