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At least 613 records · Page 34Linked to original sources
PubMed1996

Indications for surgery in upper cervical spine injury.

20% of all spine injuries are cervical spine injuries. Surgical treatment of these injuries must take into account the great mobility of this part of the spinal column. Therefore, biomechanical aspects must be considered, especially in the upper cervical spine-C1 and C2. Describing our own therapeutical regimen in 35 patients with unstable upper cervical spine injuries we explain the biomechanical back-ground and review the literature. It becomes evident that ventral approaches are superior to dorsal techniques for decompression, reposition, and stabilization with minimal loss of mobility.

Adolescent↗
PubMed1996

Relationship between atlanto-odontoid osteoarthritis and idiopathic suboccipital neck pain.

We discuss the relationship of atlanto-odontoid (AO) (anterior C1-C2 joint) osteoarthritis to suboccipital pain. A questionnaire regarding suboccipital neck pain was presented to 210 consecutive patients undergoing computed tomography (CT) of the brain or sinuses for a variety of indications. In all patients the AO joint and the lateral scout image of the cervical spine were studied. In 104 (49%) degenerative changes were seen at the AO joint. There were 89 patients (42%) who reported pain in the suboccipital region, although this was not the reason for CT in any patient. Statistical analysis of the prevalence of suboccipital neck pain in all patients showed the presence of AO osteoarthritis seen on CT to be associated with occurrence of these symptoms. This association remained significant in the same study population after excluding patients with a history of rheumatoid arthritis, migraine, stress and neck trauma and patients with signs of degenerative changes of C2-C7 on the computed lateral scout image.

Adolescent↗
PubMed1995

Association of transverse ligament calcification with anterior atlanto-odontoid osteoarthritis: CT findings.

The craniocervical junction was assessed in 700 consecutive unselected patients undergoing CT of the brain or paranasal sinuses, to investigate whether transverse ligament calcification was associated with advanced degenerative changes at the anterior atlanto-odontoid (AO) joint. Calcific deposits within the transverse ligament were seen in 40 patients (5.7%). The prevalence of this condition increased with age. Advanced degenerative changes (marked osteophytes and obliteration of the joint space) at the anterior AO joint were significantly more frequent in patients with transverse ligament calcification than in age-matched controls. We conclude that transverse ligament calcification is seen frequently in the elderly and very frequently with advanced degenerative changes at the anterior AO joint.

Adult↗
PubMed1996

Direct anterior fixation of odontoid fractures with a hollow spreading screw system.

Direct fixation of odontoid fractures has the advantage of preserving rotation in the atlanto-axial motion segment. Early mobilisation of patients and minor intra-operative trauma increase the value of this technique. The original screw method of Nakanishi, Magerl, and Böhler, was improved by Knöringer who designed a double-threaded screw for direct fixation of dens axis fractures. He stated that double screwing is absolutely necessary in order to prevent rotation of fragments against each other. The purpose of the present study was to describe a new single screw for direct fixation of odontoid fractures, which is easy to place into the limited space of the dens axis and which offers enough rotational stability and sufficient compression of fracture fragments. The so-called hollow spreading screw system (HSS) consists of an outer hollow screw, a spreading insert, a toothed washer, an hexagonal nut, and a protective nut. Thirty-five patients with traumatic and arthritic odontoid fractures were treated using direct internal fixation with the HSS system. In 30 cases, there was a type-II-fracture, in 3 a shallow type-III-fracture, and in 2 a type-II-fracture with pseudarthrosis formation. Pre-operative neurological deficits were seen in 16 cases. No additional neurological deficits were caused by the surgical procedure. The bony fusion rate of fresh fractures in the presented series was 100%. With the HSS system, ca. 12% postoperative complications, such as slight reduction of head rotation or neck pain, were found. These results are virtually equal to the results of the double-screw technique. Since a relatively simple technical procedure is required for placement of the screw, the HSS system can be recommended in all cases of odontoid fractures suitable for direct anterior fixation.

Adolescent↗
PubMed1997

An atlas vertebra with a centrum? A case report of an abnormal atlas and axis.

This case report represents the finding of an abnormal atlas vertebra during dissection of 34 cadavers. The case which we describe appeared to have an atlas with a mass at a position similar to that of a centrum. This mass may have been a developmental abnormality of the centrum of the atlas or may have represented a congenital abnormality, known as the os odontoideum. Alternatively the abnormality may have been due to non-union of an odontoid fracture, with subsequent fusion to the atlas. The case report will discuss which of these three alternatives is more probable, and the embryology and phylogenesis of the atlas and axis, leading us to believe in a congenital hypothesis as an explanation for the malformation.

Cadaver↗
PubMed1994

Congenital malformations of the craniovertebral junction: classification and surgical treatment.

The clinical, radiological and surgical findings of 56 patients with congenital malformations of the craniovertebral junction who underwent surgical intervention in the Department of Neurosurgery, Hacettepe University Medical School were reviewed. The anomalies were classified according to their embryonic origin. Forty-two cases of the series were major abnormalities formed by the combination of more than one germ layer.

Adolescent↗
PubMed1986

Transclival transcervical approach to the upper cervical spine and clivus.

The transclival-transcervical approach to lesions of the craniocervical junction is described. It gives reasonable access to the lower part of the clivus and to C1 and C2 for removal to tumours and stabilization of fractures and otherwise caused dislocations of this region. Because an opening of the pharynx can be avoided, reconstruction work can be done using bone graft or reinforced methyl-methacrylate without risk of infectious contamination. The results obtained in 6 cases are presented.

Aged↗
PubMed1995

Craniovertebral junction anomalies in inherited disorders: part of the syndrome or caused by the disorder?

Patterns of skeletal abnormality at the craniovertebral junction in the normal population and in syndromes such as Down, Morquio etc, are compared and the recent embryological data and comparative anatomy reviewed. The authors' view based on their own clinical and radiological experience is that the os odontoideum is the product of excessive movement at the time of ossification of the cartilaginous dens and is exactly analogous to the unfused Type II odontoid fracture. True hypoplasia of the odontoid peg is part of a wider segmentation defect associated with Klippel Feil, occipitalised atlas and/or basilar invagination; it is hardly ever associated with instability.

Animals↗
PubMed1995

Crowned dens syndrome: a manifestation of hydroxy-apatite rheumatism.

Crowned dens syndrome is defined as an association of acute cervical pain and calcifications in the peri-odontoid space. The authors report one case of this rare localization of hydroxy-apatite rheumatism and review 12 similar cases in the literature. This disease affects only adult females. Patients present with inflammatory signs, can be treated with non-steroid anti-inflammatory drugs and recover without sequela. Calcium pyrophosphate dihydrate deposition can also lead to this syndrome. Other perioodontoid calcifications and ossifications, usually asymptomatic, appear only as a radiologically crowned dens.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1994

Odontoid fractures. Review of 150 cases and practical application for treatment.

A total of 150 odontoid fractures was treated over a 12-year period, 43 by anterior screw fixation. The rate of pseudarthrosis dropped from 20% to 5% in type II unstable fractures. Thus, anterior screw fixation seems to be safe and efficient, and may be more widely used to treat all type II and some type III fractures. Odontoid pseudarthrosis is usually tolerated quite well and therefore requires no correction. If necessary, anterior grafting with fixation can be proposed as an alternative for posterior fusion.

Bone Screws↗
PubMed1986

[Peculiarities of juvenile vertebral fractures and dislocations of the cervical vertebrae].

In addition to diagnostic and therapeutic problems of the bony spine injuries in childhood, questions of the participation of the growth plate arise and indicate the following treatment. In the last decade we treated 23 spine injuries, resulting after fall from height. Most of the cases showed single to multiple compression fractures of the anterior spine followed in a descending frequence by the lateral compression fractures, the disconnection ot the epiphyseal plate of the axis and the actual luxation fractures with injury of the stratum germinativum. In contrast to the prognostic favourable impression fractures with a spontaneous correction, luxation fractures with or without paraplegia must be repositionned and stabilized.

Cervical Vertebrae↗
PubMed1994

[Morphology of the surgically treated dens fracture].

The peculiarities within the microarchitecture of the base of the dens have to be assumed as one of the underlying causes for type II and III fractures of the dens according to Anderson and D'Alonzo. As can be demonstrated in a section of the dens of a patient after primary osteosynthesis using two small fragment AO cancellous screws this leads to multiple local trabecular fractures and destruction of the cancellous microarchitecture. Further more compression by the screws results in a higher density of the bone mass in the region of fracture. Apart from the fact that two AO screws guarantee rotational stability, this type of osteosynthesis seems to favour intracorporal bony fusion by increased trabecular bone volume and induction of microcallus within the base of the dens. In a patient with a small intracortical transverse diameter of the dens the available space is completely filled by the screws threads. Partial penetration of the threads through the cortical bone seems to be of no clinical and biomechanical relevance and can be avoided using screws of smaller diameter.

Aged↗
PubMed2001

Posterolaterally displaced type IIA odontoid fractures.

A case of type IIA odontoid fracture with posterolateral dislocation accompanied by spinal cord injury is presented. Cervical traction was employed but reduction could not be achieved with up to 8 kg of traction. The patient was treated with intraoperative reduction and C1-2 posterior transarticular screw fixation with supplemental bone-wire fusion, and rigid fixation was obtained without any complication.

Bone Screws↗
PubMed1999

[Operative versus non operative treatment of odontoid non unions. How dangerous is it not to stabilize a non union of the dens?].

INTRODUCTION: Injuries precede the vast majority of all odontoid pseudarthroses. Because of specific anatomic conditions type II injuries lead more often than other types to non unions. For its development insufficient internal or external fixation and a persisting fracture gap are crucial. METHODS AND RESULTS: In 71 patients after operative stabilization of odontoid fractures with two anterior lag-screws we detected 8 non unions. In 3 patients the interval between accident and operation amounted to more than 5 weeks, seven times we did not succeed in closing the fracture gap. Technical mistakes like insufficient reduction (n = 1) or screw misplacement (n = 3) were additional reasons. According to the literature and own observations an os odontoideum must be considered in most instances as a pseudarthrosis after a lesion of the subdental synchondrosis in childhood. The most important diagnostic tool in odontoid non unions is a dynamic examination of the upper cervical spine under fluoroscopic control in maximum flexion and extension. We propose a classification of posttraumatic dens non unions into 4 types. Type I corresponds to a stable "non union" in approximate anatomical position of the dens and without signs of instability in the former fracture zone. Type II describes a relatively stable grossly displaced non union that is not to be reduced by simple, closed means. Type III means an unstable non union and Type IV a posttraumatic os odontoideum. CONCLUSIONS: Therapeutical recommendations need to be differentiated. Unstable non unions are most often responsible for persistent pain, may result in acute or chronic myelopathy++ and therefore - as well as ossa odontoidea - need operative fixation. In considerably displaced non unions a closed reduction manoeuver with long term traction should be tried. The operative treatment of choice is the posterior transarticular screw fixation C1/C2 desirably in a percutaneous technique. Tight, "stable" pseudarthroses in the sense of a persisting fracture gap in painfree patients should first be controlled radiologically. If the odontoid position remains unchanged, non operative treatment may be continued.

Bone Screws↗