Biomedical subjects
W Strecker
Publications and source records attributed to W Strecker.
[Correcting torsion after intramedullary nailing osteosynthesis of the lower extremity].
Intraoperative control of torsion is delicate in intramedullary nailing of femur and tibia fractures. Post-traumatic torsional deformities cause clinical problems if the rotational 0-position, according to the neutral-0-method, cannot be attained or exceeded. The necessary precondition for every indication and planning of corrective osteotomies is conscientious analysis of the geometry of the lower extremities by clinical means, radiography and computed tomography. Operative procedures and techniques of corrective osteotomies in case of torsional deformities after intramedullary nailing are presented. Preoperatively, the intraindividual torsional differences in 15 patients with maltorsions of the femur were 33 degrees (-37/+50) and in 7 patients with maltorsions of the tibia 23 degrees (-21/+29). Positive signs indicate external and negative signs of internal maltorsions. Postoperatively, the intraindividual torsional differences were 6 degrees (-3/+14) in the femora and 7 degrees (+3/+12) in the tibiae. Therefore, the physiological torsional tolerance of 15 degrees was respected in all 22 patients. Additionally, limb lengthening was realized in 4 patients with shortening after intramedullary nailing of the femur. In 3 patients a one-step procedures with interposition of allogeneic cancellous bone in the osteotomy gap was performed and in one patient continuous callus distraction by external fixation.
[Unilateral stepwise lengthening osteotomy of the femur].
Intraindividual length differences up to 1.2 cm in femora, up to 1.0 cm in tibiae and up to 1.4 cm in whole leg length can be regarded as physiological. Length differences in childhood are frequently compensated for by functional adaptation in the chain of adjacent limbs. In adults, however, that adaptability is diminished and correction osteotomy after post-traumatic shortening may therefore be indicated more generously dependent on local and general criteria of operability. A conscientious analysis of bone geometry by clinical means, radiology and computed tomography is mandatory for the indication and planning of any correction osteotomy. Intraindividual leg length differences of more than 4 cm are preferentially treated by continuous callus distraction techniques. Shortening by less than 4 cm, however, is suitable for a one-stage stepwise prolongation osteotomy in the metaphysis of the femur, i.e. in the subtrochanteric or supracondylar region. These osteotomies are than stabilized by long condylar plates; the bony defects are filled up by auto- or allogenous corticospongeous bone. Simple modifications of the stepwise prolongation osteotomy permit additional corrections of torsional deviations up to 20 degrees or of axial deviations in the frontal or sagittal plane up to 5 degrees. The results of 24 one-stage stepwise prolongation osteotomies of the subtrochanteric and supracondylar femur after congenital or post-traumatic shortening are presented as well as the reason and respective therapies for three important complications.
[Intramedullary pressure reduction in the femur shaft in total hip endoprosthesis. Effect on the rate of thrombosis].
The incidence of deep-vein-thrombosis is claimed to be reduced by avoiding intramedullary compression in the femur during implantation of the femoral part of a hip prosthesis. A double-blind randomized trial investigated 101 patients with and 102 without avoidance of intramedullary compression. There was no evidence of the benefit of this technique, for the reduction of postoperative deep-vein thrombosis.
[Liberation of soluble CD14 (sCD 14) in plasma of trauma patients].
Membrane-fixed CD14 acts as a receptor for the protein-bound endotoxin (LPS) complex and mediates the cellular effects of endotoxin. Soluble CD14 (sCD14) is suggested to neutralize circulating LPS, i.e., acting as an endotoxin antagonist. The aim of this study was to elucidate the release of both sCD14 and endotoxin in traumatized patients, starting from the earliest phase after trauma. A total of 15 patients (O ISS = 19, 9-75) suffering major trauma were enrolled in this prospective study. Blood samples were collected as early as immediately at the site of accident, on hospital admission, and thereafter hourly, then daily. For patients (O ISS = 47) died within 24 h because of their severe injuries. Immediately after the accident as well as during the first 2 h after hospital admission, the mean sCD14 levels of surviving patients did not differ from those of healthy volunteers (n = 53). Thereafter, however, sCD14 increased continuously in the trauma group. The concentrations remained elevated throughout the entire observation period. There was, however, no relation between the sCD14 release and the pattern or the severity of injury. In contrast, endotoxin levels revealed a pattern-specific release. The highest plasma concentrations of LPS were observed in patients suffering from (additional) thoracic injury. On the basis of these results we conclude that the release of sCD14 after trauma does not reflect a strict principle such as action/reaction caused by the appearance of endotoxin immediately after the injury. Soluble CD14 is more likely release by an endotoxin-independent mechanism.
Chest trauma and its impact on the release of vasoactive mediators.
Every year, major chest injury is involved in 56% of deaths in trauma victims. Blunt chest trauma apparently plays a crucial role in trauma-induced death of multiply injured patients. Therefore, the aim of this study was to evaluate the impact of different types of injuries, including lung tissue damage, on the release of various prostanoids. In a prospective study, the release of arachidonic acid (AA) metabolites was estimated in patients suffering blunt chest trauma alone, i.e., single thoracic injury, and in multiple injured patients including blunt chest trauma. The results were compared with those of patients suffering from single long bone fractures of the leg without additional injury. The plasma concentrations of the AA metabolites, prostacyclin, thromboxane, prostaglandin F2 alpha, and prostaglandin M were determined immediately after admission and in hourly and daily intervals thereafter. Despite clearly different injury scores, elevated levels of circulating AA metabolites were found in the plasma in all patients. This study reveals that any trauma increases significantly the release of prostanoids into the peripheral blood without regard to the impact of tissue damage. This phenomenon is, however, most pronounced following lung injury. On the basis of these results we suggest that there is a specific impact of those mediators in blunt chest trauma. The prostanoids apparently are suitable to describe and even to monitor the extent of thoracic trauma, thus giving additional information in some respect to the individual outcome.
Length and torsion of the lower limb.
Corrective osteotomies are often planned and performed on the basis of normal anatomical proportions. We have evaluated the length and torsion of the segments of the lower limb in normal individuals, to analyse the differences between left and right sides, and to provide tolerance figures for both length and torsion. We used CT on 355 adult patients and measured length and torsion by the Ulm method. We excluded all patients with evidence of trauma, infection, tumour or any congenital disorder. The mean length of 511 femora was 46.3 +/- 6.4 cm (+/-2SD) and of 513 tibiae 36.9 +/- 5.6 cm; the mean total length of 378 lower limbs was 83.2 +/- 11.4 cm with a tibiofemoral ratio of 1 to 1.26 +/- 0.1. The 99th percentile level for length difference in 178 paired femora was 1.2 cm, in 171 paired tibiae 1.0 cm and in 60 paired lower limbs 1.4 cm. In 505 femora the mean internal torsion was 24.1 +/- 17.4 degrees, and in 504 tibiae the mean external torsion was 34.9 +/- 15.9 degrees. For 352 lower limbs the mean external torsion was 9.8 +/- 11.4 degrees. The mean torsion angle of right and left femora in individuals did not differ significantly, but mean tibial torsion showed a significant difference between right (36.46 degrees of external torsion) and left sides (33.07 degrees of external torsion). For the whole legs torsion on the left was 7.5 +/- 18.2 degrees and 11.8 +/- 18.8 degrees, respectively (p < 0.001). There was a trend to greater internal torsion in femora in association with an increased external torsion in tibiae, but we found no correlation. The 99th percentile value for the difference in 172 paired femora was 13 degrees; in 176 pairs of tibiae it was 14.3 degrees and for 60 paired lower limbs 15.6 degrees. These results will help to plan corrective osteotomies in the lower limbs, and we have re-evaluated the mathematical limits of differences in length and torsion.
[Local complications of intramedullary nailing].
In the period from January 1990 to the end of December 1995 intramedullary nailing was performed in 294 patients with 156 fractures of the femur and 162 fractures of the tibia. Early nailing within the first 24 h after trauma was realized in 70% of the femur and in 64% of the tibia fractures. A synopsis focusing on local complications after intramedullary nailing is given on the basis of our results and a thorough analysis of the literature. Iatrogenic fractures of the femoral neck (0-5%), of the proximal femur (0.8-11.2%) and of the tibial head (0-8.3%) represent important intraoperative complications. Less frequent, but even more serious, are intraoperative lesions of nerves and arteries, as well as the development of compartmental syndromes of the lower leg (0-8.6%). Lengthy procedures and the use of traction tables seem to foster those complications. After primary intramedullary nailing, non-unions of the femur can be expected in 1-2% and of the tibia in 2-4%. The corresponding rates of osteomyelitis are 1-1.5% and 2-3%, respectively. After secondary nailing, particularly when changing from external fixation, and in cases of open fractures, the risk of deep infection is essentially elevated. Intramedullary nailing of the femur presents an important tendency to external torsional malalignment. In our investigation the torsional tolerance of 15 degrees was exceeded in 26%. A corresponding postoperative shortening of more than 2 cm length difference can be expected in 1.7-9.8%. Spiral fractures of the distal tibia offer a critical tendency to secondary varus and torsional malalignment, particularly after unreamed nailing and consecutive shortening due to breakage of locking bolts. The therapeutic indications of fracture stabilization in cases of unstable metaphyseal fractures should be reviewed.
Plasma concentrations of endotoxin and antiendotoxin antibodies in patients with multiple injuries: a prospective clinical study.
OBJECTIVE: To investigate the time course of endotoxaemia and its effects on the synthesis of antiendotoxin antibodies in patients with multiple injuries. DESIGN: Prospective clinical study. SETTING: University hospital, Germany. PATIENTS: 40 Patients with multiple injuries and 20 healthy volunteers who served as controls. INTERVENTIONS: Blood samples were collected up to 10 days after injury and the concentrations of endotoxin, antiendotoxin antibodies to four endotoxins, and for anti-alpha-haemolysin of Staphylococcus aureus were measured. The kinetics of endotoxaemia and antiendotoxin antibodies were investigated. RESULTS: Endotoxaemia peaked 0-3 hours after injury at 0.425 EU/ml and decreased thereafter to 0.04 EU/ml within five days. Total concentrations of IgM, IgA, and IgG increased continuously after day 3 (p < 0.05), but the specific IgM response to all endotoxins was only temporary and the relative content of specific antibodies to all endotoxins peaked at day 3 (p < 0.05). Antiendotoxin antibodies of IgM class cross-reacted among themselves. There was no general increase in specific antiendotoxin antibodies of IgA and IgG class. The relative content of specific antibodies to alpha-haemolysin of S aureus of all classes of immunoglobulins (IgM, IgA, IgG) remained on the same level from day 0-10. CONCLUSION: Multiple injuries are associated with early and temporary endotoxaemia which causes specific increases in antiendotoxin antibodies of the IgM-class. IgM antibodies to endotoxins cross-react among themselves.
[Are ISS and PTS unsuitable trauma scores for prediction of (possible) post-traumatic lung failure?].
Prostanoids are inflammatory mediators which originate from endothelial cells following local tissue damage. That is why plasma levels of prostanoids are possible markers of inflammatory response and severity of trauma. We were able to demonstrate that the systemic release of prostanoids does not depend on the score values (ISS, PTS) but rather on different trauma patterns (chest trauma, head injury). Influencing vascular permeability and resistance elevated plasma levels of prostanoids may explain the impairment of pulmonary function in traumatized patients. It seems to be useful to re-evaluate the scoring systems with respect to chest trauma and head injury.
Endotoxemia and specific antibody behavior against different endotoxins following multiple injuries.
The aim of this study was to establish the incidence of endotoxemia and the influence of endotoxin on specific antibody response after multiple injury. Blood samples were collected from 39 patients (median Injury Severity Score: 20.5) at 0-3 and 6-12 hours, and 1, 3, 5, and 10 days after admission. The endotoxin plasma levels were high at the first time point (mean = 0.421 endotoxin units/mL) and decreased in the later course. Total immunoglobulin levels of IgM, IgG, or IgA were low and increased throughout the observation period. Specific antibodies of the IgM class against two lipid A and four lipopolysaccharide preparations increased transiently but significantly on day 3 and/or day 5. No changes of specific antibody content against endotoxin or lipid A was seen in the IgG or IgA class. The specific antibody content of the different classes against alpha-hemolysin of Staphylococcus aureus did not differ during 10 days after trauma. The specific antibodies of the IgM class reacted with all lipid A and LPS lipopolysaccharide preparations demonstrating cross-reactivity. These results suggest that endotoxin may be a specific stimulator of IgM antiendotoxin antibody secretion following trauma.
Diagnosis of pyogenic abscesses by ultrasound.
Pyogenic infections are common in tropical countries and draining pus is one of the most frequent surgical operations all over the developing world. While superficial abscesses are easily detectable by clinical means the diagnosis of deeper abscesses in muscles, joints, parenchymatous organs and body cavities is frequently difficult or even impossible. In those situations B-mode ultrasound represents a valuable diagnostic tool. Furthermore, diagnosis may be confirmed or defined by ultrasound guided needle aspiration and ultrasound-guided drainage. Those measures may save surgical interventions and cost. Based on our experience with more than 3820 ultrasound examinations in 2746 patients of Northern Zaire sonographic characteristics of pyogenic abscesses are defined. Clinical examples of pyogenic affections with the corresponding ultrasound morphology are presented.
Epidemiology and clinical manifestation of HIV infection in northern Zaire.
1275 patients were evaluated for HIV-1 + 2 seroprevalence and its association with clinical symptoms of HIV infection. Of 667 apparently healthy subjects, 8.2% had anti-HIV-1 antibodies. In 465 patients with clinical signs of AIDS, 39.4% were seropositive. 143 patients with miscellaneous symptoms had positive predictive values for HIV infection between 67% (vaginal ulcerations) and 20% (profound pyogenic abscesses). The WHO definition for AIDS had a specificity of 78.3%, a sensitivity of 72.2% and a predictive value of 61.6%.
[Computerized tomography measurement of torsion angle of the lower extremities].
The precise evaluation of post-traumatic deformities is indispensable when planning a corrective osteotomy. Torsional angles of the lower extremities of 186 patients were measured using CT. The mean age of the studied population was 34 years (18-80). It consisted of 131 men and 55 women. All patients had sustained a fracture of at least one of the leg's bony segments. The normal femoral (n = 293) inward torsion measured 23.47 degrees +/- 17.16 degrees (mean +/- 2 SD). Normal tibia (n = 263) outward torsion was 34.03 degrees +/- 17.22 degrees. The intraindividual torsional differences were not normally distributed. Normal femoral (n = 103) intraindividual torsional difference measured 11 degrees (95% percentile) and 15 degrees (99% percentile), with a median of 4 degrees. The tibiae (n = 76) showed a normal intraindividual torsional difference of 12 degrees (95% percentile) and 15 degrees (99% percentile). Right tibiae showed a statistically significant greater outward rotation when compared to their left counterpart (P < 0.001). No correlation to sex could be established. Preoperative planning of a corrective osteotomy should include the geometric evaluation of all four bony segments of the leg. Intraindividual torsional differences must be considered. A corrective osteotomy appears to be unnecessary with a torsional difference smaller than 15 degrees in the femora and smaller than 15 degrees in the tibiae.
The microtip intramedullary probe for intraoperative pressure measurement.
The implantation of femoral stem prostheses and intramedullary fracture stabilisation are well-established techniques in traumatology. Although the biomechanical advantages of intramedullary splinting are obvious, impairments of pulmonary circulation and respiratory function are typical and feared complications. These pulmonary disturbances are strikingly correlated with operation-induced intramedullary hypertension. A simple, low-invasive and reliable system for the measurement of intramedullary pressure is presented. At the heart of the system is a microtip probe, transforming changes of pressure into electric impulses, filtered and amplified in a pressure measuring system (PMS).
Thromboxane--co-factor of pulmonary disturbances in intramedullary nailing.
UNLABELLED: Pulmonary complications during and after intramedullary nailing particularly in trauma patients have directed clinical interest to thromboembolic events and metabolic alterations, as found in different methods of fracture stabilisation. In 30 patients (mean age 34 years) isolated, closed or 1 degree open fractures of the tibia were operated on in three groups with reamed nailing (RN; n = 11), unreamed nailing (UN; n = 11) and external fixation (EF; n = 8) respectively. In blood samples of the femoral vein of the fractured limb, a 5-7 fold increase of the thromboxane (TXB2) concentration was found in all patients. However, differences of TXB2 concentrations in the arterial blood after passage of the lungs were conspicuous. The highest arterial TXB2 concentrations were found in connection with RN, followed by UN and finally EF. The transpulmonary TXB2-clearance displayed the following relationship: EF > UN > RN (5.7:4,4:2.2). A similar correlation was found for PGF2 alpha while other arachidonic acid metabolites showed no significant behaviour. TXB2 and PGF2 alpha cause bronchoconstriction, pulmonary vasoconstriction and aggregation of thrombocytes. These pulmonary disturbances may results in ARDS, a feared complication after intramedullary nailing. CONCLUSION: Early fracture stabilisation particularly in severely injured patients is an established procedure. To prevent pulmonary disturbances the external fixator is preferrable to the UN and finally the RN. Our data suggest that for the prevention of pulmonary disturbances EF is superior to UN and RN.
Indications for operative fracture treatment in tropical countries.
In the period 1 January 1987 to 30 June 1989, 3003 operations were performed at the regional hospital of Gbadolite, northern Zaire. In 123 patients fractures were reduced operatively, in 86 patients by internal fixation and in 37 patients by external fixation. There was no additional bone infection after external fixation but six of 28 patients (21%) with internal fixation by plate and screws developed postoperative osteitis. Non-union was observed in 12% after intramedullary nailing, in 4% after screw fixation alone, and 14% after internal fixation by Kirschner wires. Based on these data, indications and contraindications for operative fracture treatment in tropical countries are defined.