[Resection of retroperitoneal leiomyosarcoma followed by replacement of cavarenal segment of inferior vena cava]. / Udalenie zabryushinnoi leiomiosarkomy s rezektsiei i protezirovaniem kavarenal'nogo segmenta nizhnei poloi veny Klinicheskoe nablyudenie.

The authors reported a rare clinical case of successful surgical treatment of young female with retroperitoneal leiomyosarcoma followed by lesion of the cavarenal segment of inferior vena cava, left renal vein. Clinical and morphological features of disease, postoperative outcomes and prognostic factors in patients with retroperitoneal leiomyosarcoma are discussed.

Effect of unreamed, limited reamed, and standard reamed intramedullary nailing on cortical bone porosity and new bone formation.

OBJECTIVE: To compare the effects of unreamed nail insertion and reamed nail insertion with limited and standard canal reaming on cortical bone porosity and new bone formation. DESIGN: A canine segmental tibial fracture was created in fifteen adult dogs. The tibiae were stabilized with a statically locked 6.5-millimeter intramedullary nail without prior canal reaming (n = 5), after limited reaming to 7.0 millimeters (n = 5), or after standard canal reaming to 9.0 millimeters (n = 5). Porosity, new bone formation, and the mineral apposition rate of cortical bone were directly compared between the three nailing techniques. RESULTS: A significant increase in cortical bone porosity and new bone formation was seen in all three groups of experimental animals compared with the control tibiae. The overall lowest porosity levels were measured in the limited reamed group, with similar porosity levels measured in the unreamed and standard reamed groups. Porosity was lower in the limited reamed group in the entire cortex of the segmental and distal cross sections, as well as the endosteal, anterior, and posterior cortices along the length of the tibia. Overall, there was no difference in the amount of new bone formation or the mineral apposition rate between the three groups of animals at eleven weeks after surgery. DISCUSSION: The results of this study suggest that limited intramedullary reaming is a biologically sound alternative for the treatment of tibial diaphyseal fractures in which the circulation is already compromised.

Blood flow changes to the proximal femur during total hip arthroplasty.

OBJECTIVE: To determine the changes in perfusion to the proximal femur that occur during cemented and uncemented total hip arthroplasty (THA). DESIGN: Case series. SETTING: A single tertiary-care centre. PATIENTS: Twenty-two consecutive patients. Those who had undergone previous hip surgery or received systemic corticosteroid therapy were excluded. INTERVENTION: Cemented (11 procedures) or uncemented (12 procedures) THA. MAIN OUTCOME MEASURE: Changes in blood flow at the level of the proximal femur, measured with laser Doppler flowmetry at 4 different times during THA. RESULTS: In both the cemented and the uncemented procedure overall proximal femoral blood flow was reduced (p = 0.002, p = 0.008, respectively). A greater reduction in overall proximal femoral perfusion was seen in the cemented group compared with the uncemented group (p = 0.004). This greater reduction in perfusion was seen primarily in the proximal femoral diaphysis (p = 0.004). CONCLUSION: The extensive canal preparation involved with the cemented procedure or the introduction of bone cement under pressure into the femoral canal may contribute to the greater reduction in perfusion to the proximal femur.

Muscle perfusion after intramedullary nailing of the canine tibia.

BACKGROUND: Intramedullary nailing with and without reaming leads to a reduction in cortical bone blood flow. The repair of the devascularized bone is mediated principally by the surrounding soft-tissue envelope. The objective of this study was to determine the effect on muscle blood flow of reamed and unreamed intramedullary nailing techniques. METHODS: Midshaft tibial osteotomies to create a 2.5-cm segment of devascularized tibial cortex were performed in 19 adult canines. The tibia was stabilized with a locked intramedullary nail without reaming in 9 animals and with intramedullary reaming in 10 animals. In the unreamed group, the tibia was stabilized with a loosely fitting (n = 4) or a tightly fitting (n = 5) locked nail. In the reamed group, limited reaming (n = 5) or standard reaming (n = 5) was performed. Muscle perfusion was measured in the anterior compartment musculature of the hind-limb using laser Doppler flowmetry. RESULTS: Overall muscle perfusion was greater in the reamed group than in the unreamed group at the conclusion of the nailing procedure (p = 0.0001) and at 5 weeks (p = 0.0008) and 11 weeks after nailing (p = 0.001). The degree of canal fit of the intramedullary nails and the extent of reaming before nail insertion did not further influence muscle circulation. CONCLUSION: The results of this study demonstrate that in the presence of an intact soft-tissue envelope, intramedullary reaming of the canine tibia has a major effect on increasing the circulation to the surrounding muscles. The increased extraosseous circulation may have implications for fracture healing.

Effect of limited and standard reaming on cortical bone blood flow and early strength of union following segmental fracture.

OBJECTIVE: To quantitatively determine the extent to which limited and standard intramedullary reaming disrupts cortical circulation and to evaluate the effect on the biomechanical properties of the united fracture. DESIGN: Midshaft tibial osteotomies to create a 2.5-centimeter segment of diaphyseal bone were performed in ten adult dogs. Before insertion of a locked intramedullary nail, the tibia was reamed to either 7.0 millimeters (n = 5) or 9.0 millimeters (n = 5). Blood flow was measured using laser Doppler flowmetry during the nailing procedure and at eleven weeks postnailing. Bending stiffness and load to failure were determined for each healed tibia. RESULTS: Tibial blood flow was reduced for the limited and the standard ream groups by 63 percent (p = 0.002) and 83 percent (p = 0.0008), respectively. After canal reaming, perfusion was reduced to a greater extent in the standard ream group (p = 0.009). At eleven weeks postnailing, tibial perfusion increased to the same levels in both groups (p = 0.43) and returned to base-line values. Bending stiffness and load to failure were reduced after limited reaming (p = 0.002, p = 0.003) and standard reaming (p = 0.01, p = 0.002) were performed. Stiffness and load to failure were reduced to the same extent in both groups (p = 0.12, p = 0.25). CONCLUSIONS: Both limited reaming and standard reaming negatively affect diaphyseal cortical circulation. Limited reaming spares cortical perfusion compared with standard reaming at the time of nail insertion. No long-term advantage for limited reaming was demonstrated. Limited reaming may be advantageous acutely for the stabilization of tibial fractures in which the circulation is already compromised.

Cortical bone blood flow in loose and tight fitting locked unreamed intramedullary nailing: a canine segmental tibia fracture model.

OBJECTIVES: To quantitatively determine the extent to which loose and tight fitting unreamed, locked intramedullary nails devascularize cortical bone and to determine their effect on early strength of union. DESIGN: A 2.5-centimeter segment of devascularized diaphyseal bone was created in the tibiae of twelve skeletally mature mongrel dogs by means of two standardized transverse osteotomies. Stabilization of the tibia was achieved with either a 5.0-millimeter (n = 6) or a 6.5-millimeter (n = 6) unreamed, locked intramedullary nail. Bone blood flow was assessed using laser Doppler flowmetry. Bending stiffness and load to failure were determined for each healed tibia. RESULTS: At the conclusion of the nailing procedure, the overall tibial blood flow was reduced by 58 percent and 72 percent for the 5.0-millimeter and 6.5-millimeter nail groups, respectively (p = 0.001, p = 0.00004). Perfusion was reduced to a greater extent in the tightly fitting nail group (p = 0.017). At eleven weeks postnailing, cortical perfusion increased in both the 5.0-millimeter and the 6.5-millimeter nail groups (p = 0.005, p = 0.002, respectively). Perfusion increased to a higher level in the loosely fitting nail group (p = 0.007). Biomechanical properties of the healed tibiae, including bending stiffness in two planes and load to failure, were similar in the two experimental groups (p = 0.42, p = 0.09, p = 0.34). DISCUSSION: Our results demonstrate that a loose fitting nail spared cortical perfusion at the time of nail insertion more than did a canal filling nail and allowed more complete cortical reperfusion at eleven weeks postnailing. The results of this study have implications for the treatment of severe tibial shaft fractures in which the blood supply is significantly compromised.

[An improved method of preparing protein and peptide probes in mass spectrometry with ionization of division fragments by californium-252 (TOF-PDMS)]. / Usovershenstvovanniia metodika podgotovki prob belkov i peptidov v mass-spektrometrii s ionizatsiei oskolkami deleniia kaliforniia-252 (TOF-PDMS).

The addition of organic acids (picric, oxalic, citric, or tartaric) to peptide and protein samples was found to significantly increase the yield of their quasi-molecular ions (QMI) in time-of-flight 252Cf plasma desorption mass spectrometry. The yield of the ions depended on the pKa of the acid added.

[Mass spectrometric and quantum chemical study of dimeric associates of nucleosides]. / Mass-spektrometricheskoe i kvantovokhimicheskoe issledovanie dimernykh assotsiatov nukleozidov.

Deoxyribonucleosides H-bonded pairs were investigated using fast atom bombardment mass spectrometry and MNDO/H quantum chemistry method. It was shown that "rare" (enol or imin) forms of the nitrogen bases could form pairs with energy comparable with "canonical" base pair energy. It was shown that pair stability rows, which are measured using different experimental techniques, were in conformity each with other.

[Acute traumatic intracranial hematoma in children]. / Ostrye travmaticheskie vnutricherepnye gematomy u detei.

The data on 25 children patients with acute traumatic intracranial hematomas are presented. This accounts for 2.9% of a total of intracranial hematomas and 0.6% of a total of children with craniocerebral trauma. Correct diagnosis and early surgical intervention combined with therapeutic measures ensured favorable outcome in 76% of the cases.

[Conductive-capsular anesthesia in surgery of long tubular bones of the distal segments of the extremities]. / Provodnikovo-futliarnaia anesteziia pri operatsiiakh na dlinnykh trubchatykh kostiakh distal'nykh segmentov konechnostei.

The conductive-capsular anesthesia was used in 31 patients in operations on distal segments of extremities. The anesthesia was achieved by injection of 0.5% solution of novocain which is introduced into muscular capsules of the proximal segment of the extremity between two parallel tourniquets. Effective regional anesthesia took place in all the cases lower than the tourniquet. No complications were noted in the postoperative period.