Biomedical subjects

G Neander

Publications and source records attributed to G Neander.

8 recordsLinked to original sources

PubMed1999

An evaluation of bone loss after total hip arthroplasty for femoral head necrosis after femoral neck fracture: a quantitative CT study in 16 patients.

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.

Arthroplasty, Replacement, Hip↗

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↗

PubMed1993

Naproxen and paracetamol compared with naproxen only in coxarthrosis. Increased effect of the combination in 18 patients.

In a double-blind study of 18 patients with coxarthrosis the effect of 3 naproxen doses (0.5, 1.0, and 1.5 g daily) and 2 naproxen doses combined with paracetamol (0.5 g + 4 g daily and 1.0 g + 4 g daily) was investigated. Plasma levels of naproxen and paracetamol were measured (HPLC), and clinical assessment of pain, joint movement, activity of daily life and side-effects were performed at the end of the 5 treatment periods. A relationship was found between the 3 naproxen doses, naproxen plasma levels, pain at rest, and pain during movement. The combined treatment was more effective than treatment with the same naproxen dose alone. The effect of naproxen (0.5 g daily) combined with paracetamol (4 g daily) did not differ from that obtained during treatment with higher naproxen doses only. Furthermore, the effect of the highest naproxen dose was not better than the effect of the lower naproxen dose (1.0 g daily) combined with paracetamol. The main finding was that treatment with naproxen and paracetamol is more effective than treatment with higher naproxen doses alone.

Acetaminophen↗

PubMed1992

Pharmacokinetics of intraarticular indomethacin in patients with osteoarthritis.

The pharmacokinetics of intraarticular indomethacin was evaluated in 10 patients with osteoarthritis in an open labelled, randomized, cross-over study. Each patient received a single dose of 10 mg indomethacin by the intraarticular and the intravenous routes with a seven-day interval between the injections. Blood was repeatedly collected and urine was collected for 24 h after dosing. Indomethacin was rapidly absorbed from the joint, giving a maximum serum concentration (Cmax) of 0.60 micrograms.ml-1 approximately 1 h after dosing. The systemic bioavailability (f) was 80% and the mean absorption time (MAT) was about 2 h. The apparent terminal half-life and mean residence time (MRT) were 2.8 h and 4 h, respectively. The urinary recovery of total indomethacin (unchanged + glucuronides) was 24% of the dose and renal clearance (CLR) was estimated to be about 21 ml.min-1. The disposition of indomethacin after intravenous and intraarticular administration appeared to be similar. The results suggest that the intraarticular administration of indomethacin would not exclude the risk of developing untoward, systemic, concentration-dependent effects.

Adult↗

PubMed1992

Effects of desmopressin on blood loss in hip arthroplasty. Controlled study in 50 patients.

50 patients undergoing elective total hip replacement under epidural anesthesia and dextran infusion were given two doses of the vasopressin analogue desmopressin 0.3 micrograms/kg BW or placebo in a double-blinded randomized prospective study. Intraoperative blood loss and drainage loss did not differ significantly between groups, but desmopressin reduced the mean total blood loss (calculated from hemoglobin decrease and blood transfusions) by 310 mL (P less than 0.05).

Aged↗

PubMed1991

Effects on coagulation and fibrinolysis of desmopressin in patients undergoing total hip replacement.

Twelve patients undergoing total hip replacement, with regional anaesthesia and with dextran infusion for plasma expansion and thromboprophylaxis, were given the vasopressin analogue desmopressin (DDAVP) or placebo in a randomized, double-blind prospective study. In controls (n = 6) we found a prolongation of the bleeding time, low factor VIII (FVIII) and von Willebrand factor (vWF) and a decrease in antithrombin III to levels known to be at risk for venous thrombosis. Desmopressin shortened postoperative bleeding time, gave an early FVIII/vWF complex increase, prevented antithrombin III from falling to critically low values and appeared to activate the fibrinolytic system, both by tPA increase and PAI-1 decrease. Thus in the controls we found changes in both coagulation and fibrinolysis indicating a haemorrhagic diathesis as well as a risk for thromboembolism. Desmopressin induced factor changes that possibly reduce both risks.

Adult↗

PubMed1991

Blood loss in total hip replacement. A retrospective study.

Two hundred and twelve total hip replacements performed in one clinic over 1 year were reviewed. The mean operative time was 89 min and mean total blood loss 1090 ml. Homologous blood was administered to 74% of the patients. Blood loss was dependent on sex, body weight and height, but these correlations were eliminated when blood loss was related to estimated blood volume. There was no correlation to age. There was a positive correlation between operative time and intraoperative blood loss, but not between any of these factors and postoperative blood loss. Operative time varied significantly between surgeons, but there was no correlation between surgeon's experience and operative time or blood loss. Despite a mean of only 12 total hip replacements per surgeon, both operative time and blood loss were small compared to what was found in other studies. The use of a posterior approach is believed to contribute to a shorter operative time as well as to moderate blood loss. Intraoperative blood loss was less under epidural than under general anaesthesia, but in contrast to others we found higher postoperative blood loss after epidural anaesthesia.

Adult↗