Biomedical subjects

V Vécsei

Publications and source records attributed to V Vécsei.

At least 37 records · Page 2Linked to original sources

PubMed2001

Intracranial pressure-alterations during controlled intramedullary reaming of femoral fractures: an animal study.

Reaming during intramedullary nailing increases the intramedullary pressure (IMP) and can cause fat intravasation and subsequently lead to pulmonary dysfunction, especially in polytraumatized patients with lung contusion as well as increases in intracranial pressure (ICP).ICP changes were measured in two groups consisting of 12 sheep each with either a fractured or intact femur. The animals were exposed to haemorrhagic shock and were resuscitated by autoinfusion. Transverse midshaft fractures were created bilaterally in one group before reaming of both femoral shafts. Controlled reaming was performed at 15 and 50 mm/s driving speed (DS) and at 150 and 450 revolutions per minute (RPM) with a reaming control system using AO-Reamers. Fat intravasation was measured by transoesophageal sonography (TES) and Gurd test. ICP monitoring was performed with a piezo-electric epidural catheter. Haemodynamic and respiratory parameters, ICP, and cerebral perfusion pressure were measured continuously. High DS and low RPM caused higher IMP and ICP increases in both groups. Significantly higher microemboli were observed in TES in the fractured group as compared to the unfractured group with the same reaming parameters (P=0.021). However, the existence of a femoral fracture did not show a significant influence on changes in ICP (P-value=0.057). Reaming should be performed at a low DS and high RPM to minimize the risk of fat intravasation and the subsequent ICP increase.

Animals↗

PubMed2001

Rates and odds ratios for complications in closed and open tibial fractures treated with unreamed, small diameter tibial nails: a multicenter analysis of 467 cases.

OBJECTIVE: A multicenter trial analyzed complications and odds for complications in open and closed tibial fractures stabilized by small diameter nails. DESIGN: Retrospective. SETTING: Four Level I trauma centers. PATIENTS: Four hundred sixty-seven tibial fractures were included in the study. There were fifty-two proximal fractures, 219 midshaft fractures, and 196 distal fractures. Breakdown into different AO/OTA groups showed 135 Type A fractures, 216 Type B fractures, and 116 Type C fractures. Two hundred sixty-five were closed fractures and 202 were open fractures. OUTCOME MEASUREMENTS: Clinical and radiographic analysis. METHODS: 467 patients' tibial fractures were stabilized with small diameter tibial nails using an unreamed technique. Indications for the use of small diameter tibial nails using an unreamed technique included all types of open or closed diaphyseal fractures. The operating surgeons decided whether or not to ream based on personal experience, fracture type, and soft-tissue damage. Surgeons of Center 1 preferred to treat AO Type A and B fractures with unreamed nails, and surgeons of Centers 2, 3, and 4 preferred to treat AO Type B and C fractures with unreamed nails. Closed and open fractures were treated in approximately the same ratio. RESULTS: Analysis showed five (1.1 percent) deep infections (with a 5.4 percent rate of deep infections in Gustilo Grade III open fractures), forty-three delayed unions (9.2 percent), and twelve (2.6 percent) nonunions. Compartment syndromes occurred in sixty-two cases (13.3 percent), screw fatigue in forty-seven cases (10 percent), and fatigue failure of the tibial nail in three cases (0.6 percent). CONCLUSIONS: Fracture distraction of more than three millimeters should not be tolerated when stabilizing tibial fractures with unreamed, small-diameter nails as this increases the odds of having a delayed union by twelve times (p < 0.001) and a nonunion by four times (p = 0.057). There was a significant increase of complications in the group of Grade III open fractures (p < 0.001), AO/OTA Type C fractures (p = 0.002), and to a lesser extent in distal fractures. However, the rate of severe complications resulting in major morbidity was low.

Bone Nails↗

PubMed2001

The standard Gamma nail: a critical analysis of 1,000 cases.

BACKGROUND: The continuous increase in the number of fractures of the proximal femur is directly attributable to the worldwide increase in life expectancy. The standard version of the Gamma Interlocking-Nail (standard Gamma nail [SGN], 200-mm length, 10-degree valgus curvature, two distal locking bolts) was designed because of the demands in orthopedic hip surgery to develop an implant stable enough to mobilize old patients as soon as possible to avoid further morbidity and mortality. METHODS: Between the years 1992 and 1998, 1,000 consecutive patients with peritrochanteric fractures were stabilized by using the SGN and included in this study. Special emphasis was given to the evaluation of the learning curve of the department of traumatology (not of single surgeons) and the influence of prognostic factors on the outcome of such operations. RESULTS: The results of this study show that increasing "department experience" resulted in a reduction of the intraoperative complication rate by a factor of 0.5 (p = 0.0001) per year. This means that even an inhomogeneous mass of 78 surgeons can lower the rate of intraoperative complications by 50% per year because of increased experience. The number of early postoperative complications annually decreased by a factor of 0.8 (p = 0.0042). CONCLUSION: Late postoperative complications correlate negatively with the patient's age (odds ratio, 0.9; p = 0.0001).

Adult↗

PubMed2000

Seroprevalence of diphtheria immunity among injured adults in Austria.

Over a period of 1 year a seroepidemiological study was conducted at the outpatient clinic of a trauma department. Immunity to diphtheria was determined in serum samples from 558 injured patients (205 women and 353 men, age from 18 to 70). Diphtheria-antitoxin concentrations were measured with an enzyme immunoassay and a tissue culture toxin-neutralization assay. Sero-immunity was classified as susceptibility (<0.01 IU/ml), basic protection (0.01-<0.1 IU/ml) and full protection (>/=0.1 IU/ml) against the toxic manifestations of the disease. A total of 27.1% of the subjects were susceptible to diphtheria, 26.5% had basic protection, and 46.4% were fully protected. The median antitoxin concentration reached 0.08 IU/ml (0. 0-0.29; quartiles Q25-Q75). A non linear trend toward decreasing immunity with increasing age was observed (P<0.001) and females proved less protected than males (P=0.006). The country of original immunization (Austria, Western European countries, Eastern European countries and Non European countries) had no influence on sero-immunity (P=0.49). Multiple linear regression analysis revealed that age (P<0.001) and gender (P=0.004) had a significant independent influence on diphtheria immunity level, whereas the country of original immunization was not significant (P=0.72).

Adolescent↗

PubMed2000

[Penetrating injuries of the neck, injury pattern and diagnostic algorithm].

Penetrating neck injuries are potentially life-threatening injuries. Management is controversial despite decades of discussion in the literature. An algorithm for diagnosis and therapy is needed because of the potential risk of mortality. In the Department of Trauma Surgery of Vienna Medical School, mandatory surgical exploration after noninvasive investigations is practiced. Thirty-one patients with this kind of injury were treated between August 1992 and September 1999. Injuries were caused in seven cases by gunshots, in eight cases by broken glass, in one case by an iron rod, in one case by a spear, in one case by a branch and in 13 cases the penetrating injuries were stab wounds caused by knives. Complications like pseudoaneurysms and fistulas were not seen. No patient came to death.

Adolescent↗

PubMed2000

[Associated injuries in severe pelvic trauma].

There has been a marked increase in the incidence of pelvic fractures over the last few years. Associated injuries to the urogenital and vascular system as well as nerve injuries worsen the prognosis. Over a five year period 126 patients with severe pelvic trauma were treated. Out of these 39 (30.9%) sustained additional peripelvic injuries and represent the study sample. Type B injuries according to the AO classification occurred in 16 (41%) patients, type C fractures in 23 (59%) patients. The spleen, liver and kidney were the most frequently injured organs (58.9%), followed by urogenital lesions (46.6%), nerve injuries (25.6%) and vascular lesions (15.3%). The most common extrapelvic lesions were thoracic injuries in 56.4% and severe head injuries (GCS < 8) in 33.3%. The mean Hannover Polytrauma score was 35.6 points, the mean Injury Severity Score 27.6 points. Osteosynthesis was performed in 21 pelvic ring fractures (53%), eight procedures (50%) in type B fractures and 13 (56%) in type C fractures. In type B injuries the anterior pelvic ring was stabilized with a tension band wiring in four cases, in two patients with an external fixator and with plate osteosynthesis in one case. In type C injuries the external fixator was applied as the only stabilizing procedure in six patients. In four cases the anterior ring was fixed with tension band wiring or plates and the dorsal aspect of the pelvic ring with sacral bars. Three patients had their additional acetabular fracture plated through a anterior approach. All surviving 28 patients were followed up for an average of 18 months (range 7-59 months) after the trauma. The patients were classified using the pelvic outcome score proposed by the German Society of Trauma Surgery. 53.4% of the type B fractures showed a good clinical outcome, 47.6% a poor outcome. 15.4% with type C fractures presented with a good outcome, 84.6% with a poor outcome. 80% of the type B and 23% of the type C fractures had a good radiological outcome. 20% of type B and 77% of type C injuries had a poor radiological outcome. Five patients (12.8%) sustained persistent urological symptoms. Three of these had urinary dysfunction, two used permanent cystotomies due to their severe neurological deficit after a head injury. Ten patients with nerve injuries at the time of trauma suffered long term neurological dysfunction of the lumbosacral plexus. The mortality rate was 28%. Seven patients died in the emergency room due to uncontrollable bleeding, four in the intensive care unit from multi-organ failure. The management of complex pelvic trauma consists of fracture treatment and interdisciplinary treatment of the associated injury. Lesions of the abdominal organs or of major vessels must be addressed first if hemodynamic instability is present. Injuries to smaller vessels can be embolized percutaneously. Urinary bladder ruptures are treated as an emergency, urethral lesions electively after four to six weeks. We recommend external fixation of the pelvis in the acute phase for control of both the osseous instability and control of haemorrhage through external compression. The treatment of choice for the anterior pelvic ring is tension band wiring or plating. If this is contraindicated due to an open fracture external fixation is the treatment of choice. Type C fractures require posterior ring stabilization which should be postponed until four days post admission.

Abdominal Injuries↗

PubMed2000

Apophyseal injuries of the proximal tibial tubercle.

Avulsion fractures of the tibial apophysis are rare. Seven cases were treated between 1993 and 1998 in our department. The treatment was conservative in 1 case, in the other 6 open reduction and internal fixation was used. The results after an average of 23 months were good. There were no growth disturbances.

Adolescent↗

PubMed2000

Effect on diphtheria immunity of combined tetanus and diphtheria booster vaccination in adults.

The effect of a single booster injection of an adult formulation of a combined diphtheria-tetanus vaccine (Td) on diphtheria-specific immunity was evaluated. The booster injection, containing 2 IU diphtheria toxoid per dose, was given as part of the surgical wound management for adults with open soft tissue injuries. Diphtheria antitoxin concentrations were determined in serum samples from 534 patients (199 women and 335 men, aged 18-70 years) using an enzyme immunoassay and a tissue culture toxin neutralization assay. Seroimmunity against diphtheria toxin was classified at three levels: susceptibility, basic protection, and full protection against the toxic manifestations of the disease. Before vaccination, 27.1% of the subjects were susceptible to diphtheria, 26.5% had basic protection, and 46.4% were fully protected. Six weeks (minimum 25 days, maximum 98 days) after a single booster injection, 89.7% of the subjects achieved full protection against diphtheria, and only 3.9% had antitoxin levels below the protective level. The median increase from the prevaccination to postvaccination antitoxin concentration was found to be 14-fold (4.4-47; quartiles Q25 to Q75). The change in antitoxin levels after revaccination was higher in older age groups (P< 0.001), whereas neither sex (P = 0.86) nor the country of previous immunization with a different national immunization schedule (P=0.61) had a significant influence on the revaccination effect. Systemic adverse reactions were rare, and local reactions of clinical significance were reported in only 1.9% of subjects.

Adolescent↗

PubMed2000

Distal femoral fracture through the screw hole of a ligament augmentation device fixation.

SUMMARY: Complications associated with fixation of artificial ligaments in augmented repair of the anterior cruciate ligament (ACL) have been reported throughout the literature. However, fractures following ligament augmentation device (LAD) fixation appear to be rare. We report the case of a 43-year-old woman, injured in a road accident, who sustained a depressed fracture of the tibial plateau and knee instability. The fracture was reduced and the medial collateral ligament and the menisci were sutured. The torn ACL was repaired using the Marshall technique and augmented with an LAD in an over-the-top technique. Twenty-five months postoperatively, the patient sustained a distal femoral fracture through the screw hole of the former LAD fixation after a simple fall on the street.

Accidental Falls↗

PubMed2000

Pressure changes during reaming with different parameters and reamer designs.

Reaming increases intramedullary pressure and can cause fat intravasation. This study investigated the influence of reaming parameters on pressure changes using the AO, Gray, and Howmedica reamers. Silicone cylindrical shells with 10-, 11-, 16-, 19-, and 20-mm inner diameters were filled with a 1:2 ratio of paraffin and petroleum jelly. The 10- and 11-mm shells were reamed using a 9-mm reamer, the 16-mm shells with a 14-mm reamer, and the 19- and 20-mm shells with an 18-mm reamer. Each experiment was performed seven times while singularly varying driving speeds of 15, 30, and 50 mm per second, with a revolution rate of 150, 250, and 500 revolutions per minute. Using stepwise linear regression analysis, driving speed was the most significant parameter. The lowest pressure increases occurred at the lowest driving speed and the highest revolution rate in all cylinders. The model used for this study did not take into consideration the interaction between the cortical shell and reamer head. The results of this study suggest that reaming should be done at a low driving speed and a high revolution rate using a small cored reamer head, especially during the first reaming steps.

Embolism, Fat↗

PubMed1999

Acetabular fractures: operative management and long term results.

INTRODUCTION: While the undisplaced acetabular fractures have a good prognosis after conservative treatment, the management of the displaced fractures has been a controversial issue over the last decades with variable results in their treatment and prognosis. Anatomical reduction can be only achieved operatively. The long term outcome of 209 patients with displaced acetabular fractures treated by open reduction and internal fixation was presented. MATERIAL AND METHODS: Between 1972 and 1996, 209 patients with a mean age of 38 years (15-62a) were treated for displaced acetabular fractures operatively. 161 patients could be followed up over a period of 2 to 20 years. The function of the hip joint in correlation with radiological results was evaluated according to the scheme of Merle d'Aubinge. RESULTS: Patients with single column fractures showed 90% good or excellent results followed by 55% good or excellent results in patients with transverse fractures. The highest rates of complication (20% osteoarthritis, 6% femoral head necrosis, 9% heterotopic ossification) were observed in both column fractures and in transverse and posterior wall fractures. Deep infection was observed in 6 cases (4%), superficial wound infection in 8 cases (5%). Primary sciatic nerve palsy was seen in 10 cases (6%) and postoperative peroneal nerve palsy in 6 cases (4%), all of which improved during the rehabilitation period. CONCLUSION: Displaced acetabular fractures of the weight bearing part of the dome, i.e. transtectal fractures, should be treated operatively. The operation should preferably be performed within one week after the injury.

Acetabulum↗

PubMed1999

[Fatigue stability of locking screws for unreamed tibial intramedullary nailing].

Unreamed nailing with solid tibial nails is an accepted method of treatment for open tibial shaft fractures up to grade III and of closed tibial fractures with severe soft tissue damage. However, fatigue failure of the distal locking bolts is a frequent complication. We report a mechanical study investigating the fatigue limit of six different types of locking bolts used in solid tibila nails (Biorigid Tibial nail/aap, UTN/ace, STN/Howmedica, TLN/Howmedica, delta R & T Tibial nail/Smith & Nephew, AO/ASIF UTN/Synthes). Our results prove a direct correlation between the bolt's diameter and mechanical properties. Further more we found that bolts with a continuing thread were weaker than bolts of the same diameter with only a short thread and an increased diameter at the nail's aperture. Our results suggest that mobilization with half of the average body weight (350N) allows osseous consolidation without fatique failure of any of the tested locking bolts. Some of the tested locking bolts may even withstand full wieght-bearing in a physiological walking cycle, but will not withstand the stress of a running cycle.

Biomechanical Phenomena↗

PubMed1999

[Surgical embolectomy after reanimation in central pulmonary embolism].

Central pulmonary embolism represents one of the most threatening complications in surgical patients. In most cases deep vein thrombosis of the lower extremities is the source of emboli. Despite the introduction of hypocoagulative drugs in standard surgical concepts the incidence of deep vein thrombosis remains about 10% in trauma patients. Estimated numbers of unknown cases of pulmonary embolism are supposed to be rather high too. In haemodynamically symptomatic pulmonary embolism events and especially when the patient has to be reanimated, mortality rates of up to 93% are reported in literature. After introduction of the heart- and lung-machine in the surgical concept of therapy, survival rates have increased significantly. We report on three cases of successful surgical embolectomy after CPR. In a review of literature current concepts of treatment in central pulmonary embolism are discussed.

Acetabulum↗

PubMed1999

The role of magnetic resonance imaging in routine decision making for meniscal surgery.

This clinical study evaluated factors affecting the decision for meniscal surgery in a patient population seen routinely at a trauma clinic. The study hypothesis was that patients who sustain a traumatic injury to the knee or have a long history of clinical symptoms are likelier to be operated on. We investigated 149 patients clinically and by magnetic resonance imaging (MRI). Group A (n = 62) underwent arthroscopic surgery and group B (n = 87) were treated conservatively. Multiple logistic regression analysis was used to examine correlations with regard to age, gender, injury pattern, period between the injury and first clinical examination, and MRI results. We found no significant difference between the two groups with regard to gender (P = 0.1), injury pattern (P = 0.44), or period between injury and first clinical examination (P = 0.5). Patients in group A were significantly older than those in group B (P = 0.044), and, as expected, MRI signal alterations were significantly higher in group A than in group B (P = 0.001). In acutely injured patients MRI helps to establish an accurate diagnosis, and in cases of positive MRI findings in a symptomatic patient, the surgeon should not wait 4-6 weeks but should immediately recommend surgery.

Acute Disease↗

PubMed1999

Anterior cruciate ligament reconstruction alters the patellar alignment.

Although there are many articles dealing with anterior cruciate ligament (ACL) reconstruction, there are none dealing with the possibility of changes of the patellofemoral alignment after these procedures. Forty-six patients were evaluated preoperatively and 1 year postoperatively, after undergoing intra-articular ACL reconstruction, for changes of the patellofemoral alignment. Patella-tilt and congruence angles were measured on tangential view radiographs that were taken in the supine position. Analysis of covariance was performed and revealed a significant change of the congruence angle 1 year postoperatively. The patella-tilt did not change. One year postoperatively, the patella shifted on average 5 degrees medially after ACL grafting. It can be deduced that anterior knee pain after ACL reconstruction could be caused by distinct changes in the patellofemoral alignment.

Adult↗

PubMed1999

Comparison of femoral and tibial pullout forces in bone-patellar tendon-bone anterior cruciate ligament reconstructions with a new interference fixation device.

Interference screws have become the standard method for fixing bone-patellar tendon-bone (BPTB) grafts. To avoid the inherent pitfalls and complications of interference screws, a 28-mm long and from 5 to 7 mm spreadable metal bolt with nontapping threads was developed for this study. The technical applicability and biomechanical characteristics of this new BPTB interference fixation device were investigated by dissection or tensile testing of 48 cadaveric knee specimens from young donors. No problems occurred with respect to bone plug anchoring during insertion of the spreading bolts. The clinically important linear load was 920+/-283 N for the femoral and 635+/-247 N for the tibial fixation site. Bone plug pullout was the mode of failure in all specimens. The results of this study indicate that the spreading bolt is a reasonable alternative to interference screws.

Adult↗

PubMed1999

[Conservative versus surgical therapy of perilunar dislocation and dislocation fractures].

18 perilunate dislocations and fracture-dislocations were treated at the Trauma Center of the Vienna General Hospital during the period from 1992 to 1995. Only five cases were treated without surgery. 15 of these 18 patients returned for follow-up after an average of 16 months. In ten cases good results were achieved. Radiologically, eight patients were classified as good. Overall better results were seen after surgical treatment.

Adolescent↗

PubMed1999

New instrument that uses near-infrared spectroscopy for the monitoring of human muscle oxygenation.

BACKGROUND: Early detection of vascular impairments after free tissue transfers are essential to prevent flap failure. Near-infrared spectroscopy showed good promise to monitor flaps at deep levels successfully without being invasive. The purpose of this study was to test whether the INVOS 3100 cerebral oxymeter is capable of detecting circulatory impairments. METHODS: In 10 healthy adults, near-infrared spectroscopy was used to measure regional saturation values during tourniquet ischemia and venous outflow restriction, in two test cycles. The probe, containing an infrared-light-emitting source and two infrared-light sensors, was placed below the elbow above the brachioradialis muscle. Statistical comparison of the data was performed using the Friedman test and the Wilcoxon-Wilcox test. RESULTS: Venous and arterial occlusions were characterized by an instantaneous fall of the regional saturation. Arterial occlusion showed a mean decrease of the saturation values down to 28+/-9%, whereas venous occlusion showed a mean fall of saturation values down to 51+/-12%. These falls were significant after 3 minutes of occlusion compared with baseline values (74+/-6%). The differences between arterial and venous occlusions were statistically significant. CONCLUSION: This study, designed to test less-expensive equipment, was able to measure absolute values, and was not prone to interference caused by probe movement, providing information on the oxygenation profile accurately and noninvasively, and distinguishing between arterial and venous occlusion.

Adult↗