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F Magerl

Publications and source records attributed to F Magerl.

At least 19 recordsLinked to original sources
PubMed1992

Primary posterior fusion C1/2 in odontoid fractures: indications, technique, and results of transarticular screw fixation.

Odontoid fractures, especially unstable type II fractures have a poor prognosis in respect to healing. Therefore, operative stabilization (posterior fusion C1/2 or anterior screw fixation) has been suggested for the treatment of unstable type II and for some unstable type III fractures. Compared to posterior fusion C1/2, anterior screw fixation has proven to be effective; it has the advantage of leaving the motion segment C1/2 intact, therefore preserving at least some C1/2 rotation. However, in some instances, this method of stabilization is not indicated. In these cases, posterior fusion C1/2 is the treatment of choice. Primary posterior fusion C1/2 is indicated in (a) odontoid fracture associated with comminution of one or both atlanto-axial joints; (b) fracture of the odontoid associated with an unstable Jefferson fracture; (c) unstable type III odontoid fracture, when immobilization in a halo jacket or plaster cast is not suitable, as in elderly people or polytraumatized patients; (d) atypical type II fractures (comminuted or with oblique fracture in the frontal plane); (e) irreducible fracture dislocation C1/2, e.g., several-weeks-old fracture; (f) unstable type II or shallow and unstable type III odontoid fracture, when marked thoracic kyphosis is associated with limited extension of the cervical spine; (g) unstable type II or shallow type III odontoid fracture in elderly people with degenerative narrow spinal canal; (h) pathologic fracture of the odontoid. In all these instances, posterior fusion C1/2 is the treatment of choice. We prefer the transarticular screw fixation technique. Compared to other posterior fusion techniques, it has the advantage of increased stability and allows effective stabilization of C1/2 in a reduced position as well as immediate ambulation with minimal head support. This technique can also be performed when the posterior arch of the atlas is fractured or absent. Our experience of 12 acute odontoid fractures, managed by this technique, is presented. At follow-up, all C1/2 fusions were united in reduced position.

Adult↗
PubMed1992

[Biomechanical studies of the spine. Their significance for the development of rational treatment techniques].

A treatment is rational when the goal of restoring form and function can be achieved safely and with the least possible technical input and iatrogenic damage. In the field of spinal surgery a number of techniques have recently been developed than can be termed rational. Biomechanical investigations have made a decisive contribution to the progress achieved. Forces acting on the spine and their cyclic frequency are determined from (1) calculations based on models of the human body, (2) measurement of physical parameters, e.g. intradiscal pressure, and (3) loads acting on implants. Selection of the size and form of implants and investigation of their mechanical properties are based on the values recorded for forces and cycles. In vitro examinations on deformation of bone-implant complexes exposed to predetermined loads lead to improvements in form and dimensions of implants. Finally, comparative in vitro studies with different techniques can help in answering the question as to what technique is best suited to solve a given clinical problem.

Biomechanical Phenomena↗
PubMed1991

Overdistraction: a hazard of skull traction in the management of acute injuries of the cervical spine.

In acute cervical spine trauma, skull traction is used to reduce a dislocation or fracture dislocation, to immobilize an unstable lesion until definitive treatment (operative or conservative) is possible or, more rarely, as a definitive treatment until healing occurs. This method may be dangerous when an unstable lesion is accidentally overdistracted. A few cases have been reported in the literature, some with neurological complications. We report five cases in which overdistraction was seen. Two hangman's fractures were overdistracted. One of the two patients developed a Cheyne-Stokes breathing pattern during traction which resolved after the weight was reduced. Furthermore, two hyperextension/distraction injuries (C4/5 and C6/7) and one bilateral C5/6 fracture dislocation were overdistracted without neurological deterioration. Occipitocervical dislocations, fractures of the odontoid process, hangman's fractures, hyperextension/distraction injuries and bilateral dislocations or fracture dislocations may present disruption of both the anterior and posterior elements. Therefore, these injuries are specially vulnerable to overdistraction when skull traction is used. To prevent accidental overdistraction during skull traction, we recommend the use of less weight than is generally proposed in the literature. To reduce a dislocation, we start traction weight at 2 kg and slowly increase it under continuous neurological and radiological monitoring until reduction is completed. Traction of 5-7 kg is usually sufficient; however, heavier traction may occasionally be necessary. After reduction is completed, traction is reduced to 2 kg. This weight is sufficient to immobilize a lesion until definitive treatment is possible. Inadvertent rotation may be prevented by placing sandbags on both sides of the head.

Adolescent↗
PubMed1991

Atlantoaxial mobility after screw fixation of the odontoid: a computed tomographic study.

Between 1979 and 1989, anterior screw fixation of the odontoid process was performed in 16 patients with fractures of the odontoid. One patient died suddenly 2 days after the operation. Postmortem examination could not disclose the cause of death. No other complication was noted. We followed 13 patients. At examinations 7 to 82 months after injury, all fractures were consolidated in reduced position. In all patients, a functional computed tomographic (CT) examination of the atlantoaxial rotation was performed. Atlantoaxial rotation measurement ranged from 7 to 38 degrees to the right (average: 25.2 degrees) and 7 to 41 degrees (average: 24.1 degrees) to the left side. Five patients presented a normal range of atlantoaxial rotation, 29 to 41 degrees; 3 had a rotation of 20 to 28 degrees; 3 a rotation of 10 to 20 degrees; and in 2, rotation was less than 10 degrees to one side. Our results suggest that anterior screw fixation is the therapy of choice for Type II and cephalad Type III dens fractures. However, significant complications have been reported by other authors. Therefore, a careful surgical technique is mandatory, and contraindications should be respected.

Adolescent↗
PubMed1991

Posterior stabilization of the cervical spine with hook plates.

Hook-plate fixation is designed for posterior cervical stabilization from C2 to C7. Indications remain the same as for standard posterior fixations. The prime indications are discoligamentous injuries. The plates are hooked under the lower laminas and attached to the articular masses of the upper vertebra by oblique screws. An H-graft is placed between the spinous processes. The vertebrae are compressed together by the plates at three points, the facet joints, and graft. The resulting pre-stressed system is stable in all directions. A protocol for safe reduction of cervical dislocations is observed. Of 70 patients treated from 1979 to 1986, 51 were examined 12-54 months after surgery. All fusions consolidated. Two neurologic complications not attributable to the fixation occurred. Other major complications were not seen.

Bone Plates↗
PubMed1991

[Osteotomy of the first ray in the treatment of hallux valgus].

An osteotomy of the first row for the treatment of hallux valgus is indicated for younger patients with minor to moderate valgus deformation and only minor arthritic changes in the first metatarsophalangeal joint. The osteotomy has two prominent goals: Correction of the deformity and restoration of muscle function and muscular balance. Especially the later seems to be essential for preventing failures in the long term. Osteotomies can be carried out on os cuneiforme mediale, metatarsal bone (proximal, shaft, subcapital) and phalanx. The cuneiforme osteotomy isn't recommended because of alterations in the joint between the medial and intermedium cuneiforme. Osteotomies of the proximal metatarsal bone are rarely performed and mostly combined with an arthroplastic procedure of the metatarsophalangeal joint. The disadvantage of a shaft osteotomy (Ludloff's osteotomy) is the long time for healing of the osteotomy of diaphysis of the metatarsal bone. Subcapital osteotomies are most frequently performed. With a subcapital osteotomy you can correct more deformities than with the other osteotomies. The phalangeal osteotomy is indicated just in special cases. The combination of a subcapital and a phalangeal osteotomy is recommended by Magerl in order to reduce the failure rates.

Hallux Valgus↗
PubMed1990

[Conservative treatment of classical radius fractures].

In Colles' fractures of the radius the distal fragment is slanted dorsally and radially, dislocated dorsally and radially and supinated. The radius is shortened. Furthermore a comminution-zone of the dorsal cortex is found. In closed reduction the fracture is unwedged and reduced by recreating the mechanism of trauma in neutral position, rather a light dorsiflection is maintained to check secondary dislocation of the distal fragment and shortening of the radius. The cast should push the carpus slightly palmwards and hold the hand in light ulnar-duction. Immobilization is retained for four to six weeks. Radiologic review is performed 4, 8, 12 and 16 days post reduction so that timely change to a different form of fixation is possible in case of secondary dislocation.

Casts, Surgical↗
PubMed1990

[Which distal radius fractures can be treated conservatively?].

Roughly 80% of distal radial fractures can be treated conservatively. To decide which fractures should be treated surgically and which can be treated conservatively we divide them into four categories; metaphyseal bending-fractures, epiphyseal buckle-fractures, avulsion-fractures of the articular rim and fractures of the growing skeleton. Metaphyseal bending-fractures with dorsal inclination of the distal fragment (Colles' fracture) can generally be treated conservatively, those with palmar slanting of the distal fragment (Smith's fracture) must be stabilized surgically. The intraarticular fractures (avulsion-fractures and epiphyseal buckle-fractures) must be reduced anatomically and stabilized by osteosynthesis. In the growing skeleton Aitken 0 and I respectively Salter I and II fractures can be treated conservatively.

Casts, Surgical↗
PubMed1990

Congenital fusion C0-C2 associated with spondylolysis of C2.

This is the report of a very rare malformation at the cranio-cervical junction, including congenital occipito-cervical fusion C0-C2, spondylolysis of C2, and hypoplasia of the right vertebral artery. The malformation itself is part of a Klippel-Feil syndrome with sensory-neural hearing loss on the left side, congenital high thoracic scoliosis, rib agenesis on the right side, and kidney malformations on both sides.

Axis, Cervical Vertebra↗
PubMed1989

[Peri-prosthesis fractures in total hip endoprostheses].

Periprosthetic fractures after total hip arthroplasty (THA) were found in 0.77% (33 fractures in 4280 THA). At the time of fracture the prosthesis was loose in about one-third of the cases. In most cases (63%), the fracture was located at the distal end of the prosthesis. Fractures at this location were transverse or short oblique; those situated more distally were spiral. Whereas those located along the prosthesis shaft were long oblique. Open reduction internal fixation was performed immediately for all fractures. Thirty patients were followed an average of 2.7 years (1 year-11 years) after fracture. In 28 cases stabilization was obtained using a plate. In 2 cases the prosthesis was changed at the same time as plate stabilization. 1 case the lossened prosthesis was converted to a Girdlestone. A primary change in the prosthesis without osteosynthesis was performed in 2 cases. One year after operation all fractures were healed. We recommend a large DC plate for fractures distal to the tip of the prosthesis (spiral fractures). In cases of stable THA, we stabilized the fracture at the level of the tip of the prosthesis or along the shaft of the prosthesis itself, using a wave plate with corticocancellous bone graft. Fractures along the loosened prosthesis but with good bone stock are treated by implantation of a long-stem prosthesis. If bone stock is poor, we recommend the fracture be stabilized using a plate. Only after the fracture is healed do we revise the prosthesis.

Aged↗
PubMed1988

Total posterior vertebrectomy of the thoracic or lumbar spine.

A total vertebrectomy in the thoracic or lumbar spine via a posterior approach can provide optimal neural decompression in certain severely compromised terminal patients affected with a malignant metastatic spinal lesion. The Arbeitsgemeinschaft für Osteosynthesefragen (AO) internal fixator, accompanied by methyl methacrylate reconstruction of the anterior vertebral column, provides sufficient stabilization so that immediate ambulation with minimal external support is possible. This single operative procedure allows reduction of the iatrogenic trauma by avoiding an additional anterior exposure. Total posterior vertebrectomy has been performed successfully in a total of nine cases in this study. In three early cases the spine was stabilized with posterior transpedicular plate fixation. The six most recent cases in which the AO internal fixator was used have verified the effectiveness of this fixation system. A modification of this technique may be applied to certain primary benign or malignant spinal lesions by allowing appropriate tumor resection margins and anterior corticocancellous bone graft reconstruction.

Adult↗
PubMed1987

Comparative study of the stability of anterior and posterior cervical spine fixation procedures.

Both posterior and anterior procedures of stabilization are used for operative immobilization of unstable functional units of the cervical spine. The primary stabilizing effect of each procedure was examined and the two were compared in an experimental study. To this end the functional units C-5 and C-6 were removed from ten fresh cervical spines, the discoligamentous structures being preserved, and C-6 was embedded in methacrylate. As a result of a tensile force in a vertical direction applied to the base of the spinous process of C-5, a flexion bending load was introduced into the unit, the main component of which was measured with the aid of one vertical- and two horizontal-displacement transducers. The respective tilting angle alpha and the translation were calculated on the basis of these values. Each individual functional unit was measured with and without the discoligamentous lesion. This posterior instability was then stabilized with an H-plate, a hook plate, sublaminar wiring, and various combinations of these. Our results lead to the following clinically relevant conclusions: With isolated posterior instability, posterior fixation with the hook plate appears to bring about exercise stability. With complete discoligamentous instability, the combined procedures certainly produce exercise stability, from a biomechanical point of view, the posterior hook, plate alone being capable of guaranteeing secure fixation. Exclusive posterior wiring with complete discoligamentous instability may, without external immobilization, result in permanent subluxation in the functional unit. Exclusive anterior H-plate fixation with complete discoligamentous instability requires additional external immobilization in the postoperative stage in order to prevent flexion.

Biomechanical Phenomena↗