[Reamed intramedullary nailing]. / Marknagelung nach Aufbohrung.

The stabilization of long bone fractures through reaming the medullary cavity and insertion of an intramedullary nail, with or without locking bolts, was a standard procedure in fracture treatment for a long time. With the development of nails, which can be applied without reaming, the procedure lost importance. This publication presents the mechanical principles and impact of reaming on the bone. It describes how the pressure of the drill head and drill wave leads to a compression of medullary contents into the cortical vascular system. With the development of new drilling devices the direct effects of pressurization can be minimized and then become similar to those of unreamed intramedullary nailing. Lowering the pressure during reaming also prevents the formation of mixed thrombosis on the base of a nucleus of the bone marrow in the venous circulatory system and the danger of a pulmonary embolism. The majority of experimental research shows slightly faster fracture healing after reamed nailing. In the few randomized clinical studies presented, exclusively coming from Canada, accelerated fracture healing has also been confirmed. Aside from this it was also shown that there were fewer cases of non-unions and implant failures and less need for secondary surgeries when reamed nailing was used. Despite the difficulty in rating the clinical trials presented, due to the high number of participating clinics, the impression remains that in the course of fracture healing intramedullary reamed nailing has some advantages in comparison to unreamed nailing. An obvious advantage is that earlier and sometimes immediate weight-bearing can be tolerated. Today nevertheless unreamed nailing is favoured especially in German-speaking countries. This is maybe due to the necessary classic procedure of planning, positioning on the fracture table and reaming in steps, which make the operation slightly more complex, requiring a certain amount of armamentarium and technical understanding. In any case reamed intramedullary nailing offers an alternative procedure for many indications; to treat a hypertrophic non-union of the shaft of the long bones it remains the method of first choice.

Primary stability of various forms of osteosynthesis in the treatment of fractures of the proximal tibia.

The treatment of fractures of the proximal tibia is complex and makes great demands on the implants used. Our study aimed to identify what levels of primary stability could be achieved with various forms of osteosynthesis in the treatment of diaphyseal fractures of the proximal tibia. Pairs of human tibiae were investigated. An unstable fracture was simulated by creating a defect at the metaphyseal-diaphyseal junction. Six implants were tested in a uniaxial testing device (Instron) using the quasi-static and displacement-controlled modes and the force-displacement curve was recorded. The movements of each fragment and of the implant were recorded video-optically (MacReflex, Qualysis). Axial deviations were evaluated at 300 N. The results show that the nailing systems tolerated the highest forces. The lowest axial deviations in varus and valgus were also found for the nailing systems; the highest axial deviations were recorded for the buttress plate and the less invasive stabilising system (LISS). In terms of rotational displacement the LISS was better than the buttress plate. In summary, it was found that higher loads were better tolerated by centrally placed load carriers than by eccentrically placed ones. In the case of the latter, it appears advantageous to use additive procedures for medial buttressing in the early phase.

Two procedures for Kirschner wire osteosynthesis of distal radial fractures. A randomized trial.

BACKGROUND: The treatment of displaced Colles-type fractures of the distal part of the radius remains a challenge. Two procedures for closed reduction and Kirschner wire osteosynthesis of these fractures were compared in a prospective randomized study. METHODS: One hundred consecutive patients with a Colles fracture of the distal part of the radius (AO classification 23-A2, 23-A3, or 23-C1) were treated over an eighteen-month period. One group was managed with the conventional method, described by Willenegger and Guggenbuhl in 1959, in which two Kirschner wires are introduced into the styloid process of the radius. The other group was treated with the Kapandji method, as modified by Fritz et al., in which two Kirschner wires are inserted into the fracture gap and a third is placed through the styloid process. Postoperative care was standardized for both groups and carried out according to a strict procedure. Forty patients who had been operated on according to the modified Kapandji method and forty-one treated with the Willenegger technique were available for follow-up, for a follow-up rate of 81%. The follow-up assessment was performed with a modified version of the Martini score. RESULTS: The median time to follow-up was ten months (range, six to twenty months). The results as assessed with the Martini score were, on the average, good to very good for the patients treated with the Kapandji method and satisfactory to good for the patients treated with the conventional Kirschner wire fixation. The duration of radiographic exposure was significantly shorter with the Kapandji method than with the Willenegger technique. CONCLUSIONS: Conventional Kirschner wire fixation remains a good method of osteosynthesis for the treatment of displaced fractures of the distal part of the radius. We found both the functional and radiographic outcomes of the Kapandji method to be significantly better than those of the Willenegger technique. LEVEL OF EVIDENCE: Therapeutic study, Level I-1a (randomized controlled trial [significant difference]). See Instructions to Authors for a complete description of levels of evidence.

Intramedullary pressure increase for different commercial and experimental reaming systems: an experimental investigation.

OBJECTIVE: To measure the differences in intramedullary (IM) pressure for commercial reamer systems. DESIGN: IM pressure values for the following systems were measured: AO, Biomet, Howmedica grey reamer, Richards, and Zimmer. To investigate the influence of shaft diameter, the AO reamer head was additionally connected to a small shaft (A6/A7). The pressures were measured in plexiglass tubes filled with a mixture of petroleum jelly and paraffin oil with flow properties at 20 degrees C equivalent to those of bovine medullary fat at 36 degrees C. The reaming assemblies were inserted into the tubes using a materials testing machine at a constant speed. In addition, pressure measurements were made using five pairs of human femora to compare Biomet reamers with the AO reamer with thin, flexible drives (A6/A7). RESULTS: The following pressure distributions were obtained (millimeters of mercury; mean value +/- standard deviation): 9.5-millimeter reamer: low for Biomet (272+/-39); moderate for Richards (810+/-101); and high for Howmedica (990+/-132), AO conventional (1,000+/-97), and Zimmer (1,140+/-183); 13.0-millimeter reamer: low for Biomet (132+/-21), Howmedica (204+/-45), and Zimmer (226+/-33); moderate for AO conventional (474+/-42); and very high for Richards (1,734+/-127). The second worst system (AO conventional: 1,000+/-97) became the second best system by simple reduction of the shaft diameter (A6/A7: 378+/-33). CONCLUSION: A comparison of shaft diameters and pressure increase clearly showed that the system with the thinnest shaft produced the lowest pressure values and vice versa.

[Selection of treatment in femoral shaft fractures]. / Verfahrenswahl bei der Behandlung von Femurschaftfrakturen.

It is not possible and seems not reasonable to treat all kinds of femoral shaft fractures in the same way. Any type of osteosynthesis has its own advantages and disadvantages. The decision towards an operative procedure and the application of a special method depends on the individual situation of the patient and on the familiarity and experience of the orthopedic surgeon with the different available procedures. Single fractures, shaft fractures in combination with jointnear lesions, fractures in polytraumatized patients require a differentiated approach. Doubtless, nowadays the trend to treat all femoral shaft fractures by i.m. nailing is obvious. But it seems that there still exist a lot of indications where the plate or an external fixation can be used with remarkable advantages.

[Use of the dynamic hip screw in the management of combined fractures of the femoral shaft and coxal end of the femur]. / Der Einsatz der DHS-Schraube in der Versorgung kombinierter Frakturen des Oberschenkelschaftes und des koxalen Femurendes.

Treatment of combined fractures of the shaft of the femur and near the hip joint presents special problems. The pattern of these problems is presented on the basis of four cases that had occurred during a six-month period. A useful method for the appropriate treatment of such fractures by surgical means is demonstrated.

[Current status of intramedullary nailing osteosynthesis]. / Der heutige Stand der Marknagelosteosynthese.

The article reviews the theoretical fundamentals and practical applications of intramedullary nailing. In particular, the author deals with the theoretical, mechanical and biological aspects, discusses the indications, and describes the definitely established results of medullary nailing.

[Locking of the intramedullary nail in the medullary cavity of the tibia (author's transl)]. / Die Verklemmung des Marknagels in der Markhöhle der Tibia. In vitro-Messung der Längs- und Querdeformation des Marknagels mit Hilfe von Dehnungs-messstreifen.

Whether or not an effective locking of the medullary nail in transverse direction is achieved after medullary nailing of the tibia, is a moot point in literature. Researchers agree, however, that the essential locking of the nail occurs on the longitudinal axis of the nail. The authors conducted studies with strain gauges measuring the expansion and introduced together with the nail in order to obtain information on the elastic performance of the nail in transverse and longitudinal direction. The curves plotted from the data obtained, present a typical appearance. After the tibia has been properly reamed, a medullary nail of the AO is subjected to both elastic transverse compression as well as slight longitudinal bending after nailing. In case of excessive reaming the transverse elastic effect is only slight. If, on the other hand, reaming is not effected wide enough, the bone may burst open or the nail may undergo plastic deformation.

[3 years experiences with the dynamic hip compression screw]. / Drei Jahre Erfahrungen mit der dynamischen Hüftkompressionsschraube (DHS).

The authors report on 140 cases of fractures near the hip joint, which had been treated by applying a dynamic hip compression screw (DHS). DHS is an ideal method for stabilising pertrochanteral stable and lateral fractures. In unstable pertrochanteral fractures it is recommended to use a 130 degrees or 150 degrees DHS, depending on the age and the patient's preoperative ability to walk. In medial fractures of the neck of the femur the use of DHS offers no advantage compared with screwing or total endoprosthesis. The article reports on the postoperative results. In respect of these results DHS appears to be superior to fracture nailing according to Ender.

[Para-articular fracture of the hip joint in the aged--an indication for immediate operation?]. / Die hüftgelenksnahe Fraktur des alten Menschen--Eine Indikation zur Sofortoperation?

177 patients with fractures near the hip joint were operated on between January 1983 and December 1985. The fractures were treated with Ender pinnings, total endoprostheses and dynamic hip screws (compression screw fixation). Up to June 1984 surgery was performed after the patients had been allowed a stabilisation phase of 4 days on the average, but from July 1984 onwards we aimed at performing immediate surgery within 12 hours. The second group was compared with the first group in a retrospective study in respect of recumbent period and mortality (hospital mortality and mortality after 8 months). The period during which the patients had to remain recumbent in the hospital was found to be considerably shorter, but there were no statistically significant differences in respect of mortality. The causes and consequences are discussed.

[Late results after meniscectomy]. / Spätergebnisse nach Meniskektomie.

Lesion of the meniscus is the most frequently occurring lesion in the region of the knee joint. Opinions are still divided as to the effects of partial, subtotal or total meniscectomy in provoking and/or promoting arthrosis. In this study, 70 patients with isolated injury of the meniscus were followed up on an average 11 years after meniscectomy. The subjective and clinical findings are juxtaposed with the x-ray findings. It was found that no arthrosis or no increase of the already preoperatively existing degree of arthrosis was seen in only 21.4% of the patients. Correlations are set up between instability resulting from meniscectomy on the one hand, and degree of arthrosis on the other.

[Fat embolism and fracture, a review of the literature]. / Fettembolie und Fraktur, eine Literaturübersicht.

The reasons of fat embolism as well as the following fat embolism syndrome are most likely long bone fractures, especially if the femur is participated. On the other hand there are cases, where a severe concussion of the entire body caused fat embolism. But it is also supposed, that intramedullary reaming as well as the insertion of knee- and hip-prostheses could be a releasing factor, because the applicated pressure on the medullary canal can cause a fat release in the systemic blood system. The morbidity depends on age and fracture, which is on fractures between 0.9 and 2%. The most affected group are people between 18 and 28 years of age. The fat embolism is manifesting at 46-60% of the patients in the first 24 hours and over 90% of the patients are affected in the first three days. If you look at the metabolic changes, you will find shortly after the fracturing process a rapid increase of free fatty acids (FFA), as well as an increase of the plasmatic enzyme levels (lipase, GPT, GOT, GLDH, LDH, etc.), catecholamines and glucocorticoids. In order to discuss the pathogenesis in a fairly complete way, you have to take different theories into consideration, because several parallel running processes--which are influencing each other--are leading to the syndrome. Infloating theory: Proceeding on the assumption that contents of the bone marrow are floating out of the fracture gap into the venous system and are leading to fat embolism in the lungs. Lipase theory: You can diagnose in 50-70% of the fracture patients an increase of the lipase level, which is correlating with the manifestation of the fat embolism. The lipase releases fat from the body depositories in addition to the fat, who is coming out of the fracture gap. Shock and coagulation theory: During shock the microcirculation is decelerated, the blood viscosity is increased and the suspension stability of the cellular blood components is decreased, which is leading to the sludging phenomenon. So the capillaries of the lungs and the brain are a kind of sludge filter of the blood, that is changed in its suspensions stability. Free fatty acids theory: Primary existing capillary defects are reasonable caused by free fatty acids (FFA). They are hydrolyzed of the neutral fats and are histotoxic for the walls of the blood vessels.(ABSTRACT TRUNCATED AT 400 WORDS)

[Influence of the treatment of fractures on the development of pseudoarthroses of the humerus shaft (author's transl)]. / Einflüsse der Frakturbehandlung auf die Entstehung von Oberarmschaftpseudarthrosen.

The evaluation of 98 pseudoarthroses of the shaft of the humerus showed that 42 of these occurred after conservative and 56 after surgical treatment of the original fracture. It appears that pseudoarthroses are caused in conservative treatment chiefly by the traction methods. Among the surgical methods, intramedullary nailing does not seem to bring about sufficient stabilization with a satisfactory measure of safety, whereas in the case of plate osteosynthesis, errors in respect of operation technique are mainly responsible for causing pseudoarthroses. All 98 pseudoarthroses returned to normal condition after proper plate osteosynthesis and, if necessary additional deposition of cancellous bone graft.

[Fractures in benign bone cysts]. / Frakturen bei benignen Knochenzysten.

Etiology, clinical manifestations, roentgenographic appearance and histological variations of solitary and aneurysmatic bone cyst are reported. The classification of solitary bone cyst into active and inactive cysts is important therefore prognosis and treatment are different. The critical control of our patients with fractured solitary and aneurysmatic bone cysts since 1973 resulted in a very contenting management of treatment. Active solitary bone cysts, recurrent cysts, fractured cysts and large cysts close to joints are treated by segmental resection, interposing of ribs, homologous or autogenous cancellous bone graft and plate osteosynthesis. We never found recidives under this treatment. The only curettage of active solitary bone cyst frequently is accompanied by recidive and unsatisfying functional results. Reports of local corticoid injections in treatment of bone cysts should be furthermore controlled critical.

[Indications and technique of arthrodesis of the knee joint (author's transl)]. / Indikation und Tecknik der Kniegelenksarthrodese.

The indications of an arthrodesis of the knee joint have changed and seem to be rare in a century of total arthroplasty. However, even nowadays the arthrodesis of the knee joint is still carried out with good results in: postinfectious gonarthrosis, irreparable posttraumatic instability, Charcots knee, Neoplastic destructions in special cases, for patients with a severe painful and deforming arthrosis of any reason, which are too young for an arthroplasty and in a century of arthroplasty for all patients after failure of arthroplasty. Within a period of 11 years from 1969-1980, 105 patients underwent an arthrodesis of the knee joint at BG Unfallklinik Tübingen. Indications and technique are given, the value of an individual postoperative care is pointed out.

Cortical perfusion and local fat occlusion after intramedullary nailing of the ovine tibia--comparison of different surgical procedures.

UNLABELLED: The aim of this study was to determine whether reamed or unreamed nailing is more harmful to local bone perfusion and increases fat occlusion of transcortical vessels. METHODS: After creating a standard fracture of the sheep tibia, reaming was performed in the first group using an experimental optimised reaming system (RE), in the second group with the conventional AO reamer (RC). Unreamed nailing was performed in the third group (UN). UHN 7.5mm titanium was inserted in all three groups. Intramedullary pressure was measured intraoperatively. Quantitative histological analyses of the bone were performed postoperatively. RESULTS: The highest fat occlusion of transcortical vessels occurred in UN (5.7%), the lowest in RE (1.6%). The least harm to intracortical circulation was caused by RE with 28% perfused intracortical vessels compared to 17% (UN) and 18% (RC). CONCLUSION: The experimental optimised reaming system reduces circulatory disturbance and local fat occlusion compared to the existing nailing procedures.

[Minimally invasive T-plating at the proximal humerus]. / Minimalinvasive T-Plattenosteosynthese am proximalen Humerus.

BACKGROUND: A generally accepted recommendation for the optimum surgical treatment of unstable, dislocated fractures of the proximal humerus is not yet available. According to the general surgical trend to minimally invasive techniques, the object of this study was to conduct follow-up examinations of the technique of minimally invasive T-plating at the proximal humerus developed at our hospital and to compare the results with those of other osteosynthetic techniques, especially concerning the complications of the surgical approach and the clinical outcome. PATIENTS AND METHOD: Between 1/2000 and 6/2003, 117 minimally invasive T-plating procedures were performed on 116 patients by sliding through a T-plate from a small proximal incision. After application of the exclusion criteria, a total of 100 operations on 99 patients were left. The follow-up examinations were based on the Constant score and the DASH score. RESULTS: At an average value of 70 points (SD +/- 21), the results of the Constant-Murley score were only medium to satisfactory (min. 17/max. 100 points). At an average value of 32 points (SD +/- 23), the results of the DASH score also were only adequate (min. 0/max. 78 points). A correlation between age, sex or fracture classification and the score results could not be deduced. CONCLUSION: The expectations for this technique were not met. Minimally invasive T-plating could not be shown to be superior to other techniques.

[Biomechanical and histological studies following intramedullary nailing of the tibia]. / Biomechanische und hitologische Untersuchungen nach Marknagelung der Tibia.

With our experimental work we tried to answer some special mechanical and biological questions which occur in medullary nailing of the tibia. The deformation of the nail during insertion was measured by strain gauges. In addition resistance of isolated tibial segments against torsional moments was analyzed. Thus we were able to demonstrate the occurrence and the effectiveness of an elastic interlocking of the nail in the transverse and longitudinal tibial axis. By means of dying with disulphine-blue and labelling with fluorochromes the irritation of the cortical blood flow and the revascularisation procedure on the base of a centripetally directed intensive cortical remodelling could be figured out very well. The results are not only limited to the conditions of intramedullary nailing but allow further conclusions to the general physiology of cortical blood flow and bone healing.

[Stabilization of infected fractures and pseudarthroses (author's transl)]. / Stabilisierung infizierter Frakturen und Pseudarthrosen

A procedure following the principles of modern septic bone surgery permits the prospect of bone healing in infected fractures and pseudarthroses, even in cases which at first seem hopeless. In spite of primarily atypical conditions, an improvised procedure ought to be avoided as a rule. The possibilities of a stable fixation are indicated with reference to some exemplary cases. At the same time, the need for autologous spongiosaplasty in the treatment of infected fractures and pseudarthroses is pointed out.