Biomedical subjects

H Tscherne

Publications and source records attributed to H Tscherne.

At least 217 records · Page 12Linked to original sources

PubMed1993

The incidence of osteitis in open fractures: an analysis of 948 open fractures (a review of the Hannover experience).

Even though treatment protocols of open fractures have been improved in the past two decades, osteitis is still a major complication in these injuries. To investigate the primary factors responsible for posttraumatic osteitis, 19 cases of osteitis out of 297 open fractures (retrospective series from 1981 to 1983) and nine cases of osteitis out of 651 open fractures (prospective series from 1984 to 1989) were analyzed. The Hannover fracture scale was used for quantitative evaluation of the injury. A high prognostic index for bone infections was found for the amount of bone loss, the fracture type, the type of bacteriologic contamination, deep soft-tissue defects, compartment syndromes, vascular injuries, and soft-tissue infections.

Fractures, Open↗

PubMed1993

Primary intramedullary femur fixation in multiple trauma patients with associated lung contusion--a cause of posttraumatic ARDS?

We investigated whether primary (< 24 hours) intramedullary stabilization of femoral shaft fractures in multiple trauma patients with severe thoracic injury might be associated with an increased incidence of adult respiratory distress syndrome (ARDS). A total of 766 patients with multiple trauma admitted to Hannover Medical School between January 1, 1982, and December 31, 1991, were investigated retrospectively. Of these, 106 patients met the inclusion criteria: Injury Severity Score > 18, femoral midshaft fracture treated by intramedullary nailing, primary admission or referral within 8 hours after injury, and no death from head injury or hemorrhagic shock. Two groups were differentiated according to the presence or absence of chest trauma (severe chest trauma = AIS thorax > or =, group T; no severe chest trauma = AIS thorax < 2, group N). Selection of subgroups according to the time of femur stabilization was group I < 24 hours after trauma, group II > 24 hours after trauma. Injury Severity Scores in the four groups were TI: 29.4 (n = 24); TII 31.4 (n = 26); NI 20.1 (n = 33); NII 25.4 (n = 23). In patients without thoracic trauma the ICU time (NI: 7.3 days; NII: 18.0 days) and intubation time (NI: 5.5 days; NII: 11.0 days) were lower in the patients treated primarily (p < 0.05). In patients with severe chest trauma there was a higher incidence of posttraumatic ARDS (33% versus 7.7%) and mortality (21% versus 4%) when early intramedullary femoral nailing was done. In the absence of severe chest trauma primary intramedullary femoral nailing is beneficial.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Influences of different methods of intramedullary femoral nailing on lung function in patients with multiple trauma.

We investigated the effects of primary (< or = 24 h) intramedullary femoral nailing on lung function and pulmonary hemodynamics in patients with multiple trauma. Two groups were separated: the group with primary femoral nailing with reaming (group RFN) was submitted to femoral nailing after reaming of the medullary canal; in the group with unreamed femoral nailing (group UFN) a small-diameter solid nail was inserted without reaming. Lung function was assessed by oxygenation ratio (PaO2/FIO2), and pulmonary hemodynamics by intraoperative pulmonary artery catheter measurements. Central venous blood concentrations of elastase and the platelet count were determined during and 3 days after surgery. Lung function was stable in UFN patients (n = 14), but deteriorated in RFN patients (n = 17) from 353 +/- 24 (PaO2/FIO2 preoperatively) to 260 +/- 28 (PaO2/FIO2 postoperatively) (p < 0.05) and improved only after 48 hours. Pulmonary artery pressure (PAP) did not change during surgery in UFN patients; in RFN patients PAP increased from 27.2 +/- 3.1 mm Hg (preoperatively) to 36.3 +/- 4.1 mm Hg (p < 0.05) upon reaming and normalized 1 hour after insertion of the nail. Femoral nailing after reaming represents a potential risk with respect to lung function disturbances. This might trigger the development of adult respiratory distress syndrome (ARDS), especially in patients at extra risk of this complication (additional lung contusion, "borderline patient"). In these cases unreamed femoral nailing might offer an alternative by allowing primary intramedullary stabilization without the risk of adverse effects to the lung.

Adult↗

PubMed1993

[Incidence of pseudarthroses in open fractures: analysis of 948 open fractures].

In a retrospective and prospective analysis of 948 open fractures, treated at the institution of the authors in the years from 1981 to 1989, approximately 155 variables were used to deduce factors influencing the development of posttraumatic non-unions. This analysis reveals that only variables describing the bone injury show a statistical significant influence on posttraumatic non-union. Consideration of the results of the retrospective analysis in the management protocol of open fractures led to a significant decrease of non-union rates in the prospective series of 651 open fractures. An unchanged statistical influence in the development of non-unions could be found for factors representing the bone damage of the underlying injury. Variables describing the soft-tissue injury show a linear regression with the duration of bone healing time. Using the Hannover Fracture Scale is an appropriate tool for treatment control and risk prediction concerning post-traumatic non-unions.

Cross-Sectional Studies↗

PubMed1993

[Indications and incidence of spongiosa transplantation in open fractures: analysis of 470 open fractures].

From a prospective series of 651 open fractures, treated at the institution of the authors in the years 1984-1989, 124 cancellous bone grafts in 470 open long bone fractures--651 open fractures excluding amputation after Type III open fractures, excluding traumatic amputations and open fractures of the ankle joint and foot--were analyzed using approximately 155 variables per individual fracture to deduct the influencing factors for indication and frequency of bone grafts. As a result of this analysis it could be shown that bone grafting depends significantly on variables describing the bone injury as well as the type of fixation used. The frequency of bone grafts in this series was much higher than stated in the literature. The time of surgery for bone grafting depends on the type of fixation used, the concomitant soft tissue injury and the amount of primary bone loss. In contrast to the literature the analysis revealed that for good indications the use of allogeneous bone grafts in open fractures is possible.

Adult↗

PubMed1993

[Standardized ultrasound diagnosis of instability after dislocation of the upper ankle joint].

The anterior drawer was evaluated sonographically under standard conditions (150 N load, 7.5 MHz linear scanner) in 95 patients with severe ankle sprain. A simple geometric construct of subsidiary lines set up with the help of a goniometer on the videoprints (enlargement 1.5 X) enabled a standardized interpretation of the anterior drawer (pathologic > or = 3 mm). Thus, the definition of poorly reproducible reference points for sonographic measurements became avoidable. In 60 patients a rupture of the lateral ankle ligaments was diagnosed, in 35 patients the findings were recorded as severe ankle sprains without ligament rupture. Compared with the radiological anterior drawer and talar tilt, the dynamic sonographic measurement of the anterior drawer showed the better values from the aspects of sensitivity, specificity and accuracy (> or = 0.93). In our own practice sonographic measurement of anterior drawer has replaced stress radiograms in diagnosis of ankle joint instabilities after severe ankle sprains.

Adolescent↗

PubMed1993

[Indications for anterior cruciate ligament reconstruction--current surgical techniques, choice of transplant].

At present there is still a great deal of uncertainty about the natural history of ruptures of the ACL. The literature reveals that a significant number of secondary meniscus lesions and chondral damage results, when a high activity level is maintained. Reconstruction of the ACL now improves objective stability and decreases the meniscectomy rate in a large number of cases. Replacement with a patellar tendon or semitendinosus graft and augmented repair give better results than primary suture of the ligament. A limited arthrotomy or an arthroscopic technique should be used for reconstruction of the ACL. Two tunnel techniques with a lateral incision and single incision techniques with a femoral half tunnel are used. There is no consensus at present on the optimal graft source and surgical technique for ACL reconstruction.

Anterior Cruciate Ligament↗

PubMed1993

[Quality assurance in trauma surgery--what does the TRISS method offer ?].

The TRISS method offers a standard approach for evaluating the outcome of trauma care. Based on the data of more than 150,000 patients, TRISS offers a method of calculating the individual probability of survival of trauma patients. The calculation is based on anatomical, physiological data and the age of the patient. The basic scores for using TRISS are the Revised Trauma Score and the Injury Severity Score. Recent analyses demonstrate for blunt trauma patients a sensitivity of 60.9% and a specificity of 99.2%. What does TRISS offer in comparison to other trauma scores? TRISS offers a valid approach for the screening of trauma patients regarding unexpected survival/death. Based on the largest database of trauma patients, TRISS represents a method of maintaining quality assurance for prehospital and hospital trauma patient care; it also allows comparison with international standards of trauma care.

Adult↗

PubMed1993

[Rehabilitation and reintegration of polytraumatized patients].

In this randomized study we attempt to verify treatment results, rehabilitation and social reintegration of multiple trauma patients. Two to 4 years after the accident a clinical follow-up examination was carried out on 104 multiple trauma patients with an average age of 29.5 years who had 7.7 single injuries. Patients with injuries of the central nervous system still showed neurological disorders in 32%. The initially determined Glasgow Coma Scale did not correlate with the long-term prognosis of neurological disorders. Only 4 of 38 thoracic injuries had functional disorders-these patients had required long-term ventilation therapy (> 3 weeks). Former abdominal injuries showed no objective disorders in the follow-up. Most of the injuries to the extremities (79.7%) healed without functional disorder. Only patients with lower limb injuries still had complaints. At the time of the checkup 6.7% had still not been able to work (for more than 24 months) and 26.9% for more than 12 months. The disability rate was less than 20% in 64.3%, 7.2% more than 50% and 9.6% more than 80%. Most of these patients had severe head injuries. There was a relationship between reintegration at work and the age of the patients: 49.2% of patients younger than 25 years were working in their previous profession, 26.9% had here re-educated, and only 7.9% were unemployed. However, in the age group older than 25 years, only 29.2% worked in their previous profession and 12.2% had been re-educated. This follow-up study shows that in multiple trauma patients reintegration at work and in social life is possible.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

[Results of treatment of polytraumatized patients. A comparative analysis of 3,406 cases between 1972 and 1991].

The treatment data on 3,406 patients with multiple injuries were analyzed retrospectively from the viewpoint of quality control. The diagnosis, therapy, complications and course were documented and the treatment results of two decades (1972-1981 and 1982-1991) compared. Young people with an average age of 31 years were mostly affected: 86% had fractures (40% open injuries), 69% head injuries and 62% thoracic trauma. Head injury together with thoracic trauma was the most frequent injury combination and affected the duration of ventilation therapy and the intensive care course. The relationship between the kind and severity of injury [categorized according to the Hannover Polytrauma Score (PTS)] and the lethality rate was significant. Preclinical treatment (infusion, intubation, thoracic tube) has increased in the past decade, and rescue time has been shortened. For the initial clinical diagnosis, ultrasound and the CT scan have been used more frequently. In patient treatment the elimination of massive hemorrhage still has first priority. Primary stabilization of long tubular bones, mostly of the lower limb, is aspired for. Volume therapy has changed over the last decade, so the risk of acute renal failure has been nearly eliminated. Nowadays late complications, e.g., multiorgan failure, are well in the foreground. Today at Hannover Medical School the average intensive care time is 13.7 days and the hospitalization time 31 days. When the two decades were compared, mortality was seen to have declined from 40% to 18%. In the future if the mortality rate is to be reduced further, this can only be done by treating the cause of post-traumatic organ failure.

Adolescent↗

PubMed1993

[4-fragment fracture of the proximal upper arm].

Four-fragment fractures have to be accorded great importance because they are so severe. The morphology allows differentiation of two types, the dorsolateral fracture type and the impacted fracture type. Over a 4-year time span, 13 of these fractures were treated with minimal osteosynthesis. This involve the open anatomical reduction and allogeneic spongiosa grafting and retention of the fracture with screws and, if necessary, K-wires and tension banding. After an average of 26.3 months the shoulder function was evaluated using the CONSTANT score. The dorsolateral fractures were scored of 87.2 while the impacted fractures were scored at 88.8. No necrosis of the humeral head was found. These good results show that after four-fragment fractures primary reconstruction of the humeral head should be preferred over primary prosthetic replacement.

Adult↗

PubMed1993

Staging of patellar tendon autograft healing after posterior cruciate ligament reconstruction. A biomechanical and histological study in a sheep model.

The prerequisite for adequate rehabilitation after cruciate ligament reconstruction with a patellar tendon autograft is a thorough knowledge of the biologic healing processes. It is of interest to determine whether distinct phases similar to those in wound healing can be differentiated. It is also important to assess the magnitude of the biomechanical loading capacity and the duration of the healing processes. One posterior cruciate ligament in each of 48 skeletally mature sheep was replaced with a free patellar tendon autograft. Immediate rehabilitation without immobilization followed. Four phases of healing were demonstrated using the histologic condition of the autograft as a guide. The biomechanical data were correlated with the morphologic data. During the necrotic phase, a maximum of necrotic tissue was seen two weeks postoperatively. The strength of the graft is initially limited by the surgical fixation strength; however, later the intraarticular portion becomes the strength-limiting factor. During the revitalization phase, which is characterized by revascularization and proliferation of fibroblasts, and during the following phase, collagen formation, an increase in maximum stress is seen while the elastic modulus remains constant. Only in the remodeling phase is an increase in elastic modulus seen, owing to longitudinal alignment of the collagen bundles. One year after implantation, the autograft achieves approximately 50% of the material properties of the control. Even after two years, the autograft reaches only a maximum stress of 60% and an elastic modulus of 70% of the control. Ligamentization of the autograft could not be demonstrated in this study, but degeneration was seen in the core region of the graft during late remodeling.

Animals↗

PubMed1993

[Allogeneic cruciate ligament replacement. Perspectives and initial clinical results].

There is a continuing search for the ideal substitute for the cruciate ligaments. Autogenous tissues have been widely used as a replacement. The use of allografts is an attractive alternative: no donor side morbidity, decreased operative time, smaller incisions, especially with new endoscopic techniques, unlimited supply with a choice of graft sizes in multiple ligament reconstructions and a long shelf-life are some of the distinct advantages that allografts offer. They may be useful in circumstances where there is no suitable autologous substitute or the available tendon is too short to span the joint cavity. The preparation of an allograft requires appropriate donor selection and screening, careful surgical tissue procurement, and safe and effective processing techniques. At the present time, the issue of secondary sterilization of allografts remains controversial. Subclinical immune response and the possibility of transmission of infectious agents have to be considered. The early results in the literature and in our small series are encouraging; however, long-term results are necessary prior to widespread use of allografts in cruciate ligaments reconstructions. The authors believe that allografts should presently be reserved for use as an alternative to prosthetic ligaments in situations where autografts are unavailable or inappropriate.

Adult↗

PubMed1993

Osteosynthesis of displaced intraarticular fractures of the calcaneus. Results in 123 cases.

The operative treatment of intraarticular calcaneal fractures has three principal aims: restoration of height, length, and width of the calcaneus, reconstruction of the subtalar and calcaneocuboid joint surfaces, and stable osteosynthesis using an H-plate or screws. In 68% of the cases, the sustentacular fragment was the key to open reduction, making the medial approach mandatory. In complex fractures, a lateral approach is added. In "blow-out" fractures or cases with comminution of the sustentacular fragment, an extended lateral approach only is used. For precise preoperative planning of roentgenograms in three planes, four Brodén's views and axial plus coroneal or three-dimensional computed tomography scans are required. From July 1983 to July 1990, 157 intraarticular calcaneal fractures were treated by open reduction. The results in 123 cases are 61% good or excellent, 32.5% satisfactory, and 6.5% poor. The following early complications occurred: superficial wound edge necrosis (8.3%), hematoma (2.5%), nonunion (1.3%), and infection (1.9%). Four patients (3.3%) in the follow-up group have developed degenerative changes severe enough to require subtalar fusion. To facilitate the comparison of results, new fracture classification and follow-up scoring systems have been devised.

Adolescent↗

PubMed1993

[Rupture of the anterior cruciate ligament. Current status of treatment].

This article summarizes the present knowledge on the diagnosis of and treatment rationales for ruptures of the anterior cruciate ligament (ACL) of the knee. There is an increasing incidence of this injury due to the high number of persons involved in dynamic sports. The most significant diagnostic criterion is a positive pivot shift associated with a pathological anterior translation of the tibia in slight flexion of the knee. Instrumented testing of the knee is becoming increasing important and is standard in follow-up studies. A survey of the literature at present delineates very clearly the importance of an intact ACL for homeostasis of the knee. Loss of this structure leads to a high incidence of secondary meniscus tears with consecutive osteoarthritis of the knee. All valid studies also indicate an involuntary decrease of activity in the patients after loss of the ACL. Risk factors for early decompensation of the knee are a young age, high activity level, rupture of the collateral ligaments, congenital laxity, varus morphotype and high initial laxity. Primary repair of the ACL is possible, but results in stable ligament healing in only a limited percentage of cases. Reconstruction of the ACL with a free patellar tendon graft has become the standard procedure for many surgeons. ACL reconstruction can be performed either arthroscopically or through a "miniarthrotomy" with comparable results. Augmented repair or reconstruction using autologous flexor tendons is an alternative in certain cases. Augmentation with allogeneic material and the use of tendon allografts are still experimental and should be restricted to centers that can perform strict follow-up studies. The rehabilitation program after implantation of a patellar tendon graft can be accelerated markedly without endangering joint stability. Crutches are necessary only for the first 2-3 weeks. The success rate in terms of objective stability with an autologous patellar tendon graft is high, although specific disadvantages such as chronic patellar pain and a risk for loss of motion must be considered.

Anterior Cruciate Ligament↗

PubMed1993

[The value of bone scintigraphy in thigh pain following cementless hip prosthesis].

Persisting postoperative pain of the thigh is a common problem of cementless hip endoprostheses occurring in about 15-20% of the patients. We performed a comparative study including patients with (n = 40) and without (n = 45) pain of the thigh. 85 cementless porous-coated anatomic (PCA) hip endoprostheses in 74 patients were examined. All patients underwent clinical examination including a standardized questionnaire, x-ray, and 3-phase bone scintigraphy. Slight or moderate 99mTc-MDP uptake in the area of the greater and lesser trochanter as well as at the tip was a common finding in PCA prostheses in patients without pain and was not a sign of loosening of the hip. Radiologically, there was no difference between patients with and without pain. However, persisting pain of the thigh in patients with PCA prosthesis corresponded with an increased uptake at the tip and the medial and lateral femur, not being a sign of loosening even in this group. The special biomechanical conditions of cementless prostheses causing inhomogeneous intraosseous stress distribution are supposed to be the reason for that.

Adult↗

PubMed1993

Tibial plateau fractures. Management and expected results.

The objective of treatment of tibial plateau fractures is precise reconstruction of the articular surfaces, stable fragment fixation allowing early motion, and repair of all concomitant lesions. A classification scheme is employed to include the high incidence of concomitant lesions in specific fracture types. The term "complex trauma" is used for extensive injuries involving multiple structural elements of the knee joint. Exact grading of the soft-tissue injury is crucial for the treatment plan. The authors suggest a four-grade classification system of closed and open soft-tissue injury. Preferred treatment is open reduction and internal fixation (ORIF) in all displaced and unstable tibial plateau fractures. A stepwise approach is used in complex knee trauma. Primary treatment includes closed reduction, wound debridement, if necessary, and external fixation of the femur and lower leg ("transfixation"). Open reduction and internal fixation and complex bone and soft-tissue reconstructions are performed in a second operation after recovery of the soft tissues. A follow-up study of 190 of 244 cases of tibial plateau fractures treated in the authors' institution from 1981 to 1987 showed good results after operative treatment, even in extensive fractures, with a tolerable complication rate. The functional recovery was relatively impaired in multiple injured patients and in complex knee trauma.

External Fixators↗

PubMed1992

The pelvic compartment syndrome.

In the pelvic region three major compartments (gluteus medius-minimus compartment, gluteus maximus compartment, and iliopsoas compartment) can be distinguished from the smaller compartment of the tensor fasciae latae muscle. Pelvic compartment syndromes are rare. A clear history of trauma is often lacking. Association with drug and alcohol abuse is common, as is the association with the widespread use of anticoagulant therapy. From 1982 to 1990 six patients with acute buttock compartment syndrome were treated in the Department of Trauma Surgery of Hannover Medical School. In five patients fasciotomy of the gluteal compartment was performed. Two patients with a compartment syndrome secondary to necrotizing fasciitis died of septic multiple organ failure. The mean follow-up of the four other patients was 29 months (7-48 months). Three of these four patients revealed a decrease of gluteal muscle volume. Ergometric tests showed a decrease in gluteal muscle force in all patients.

Adolescent↗