Reduction and fusion of fracture of the odontoid process

Plate and screw fixation for atlanto-axial subluxation

Our experience with 30 cases of atlanto-axial dislocation, over the period of 3 years and 9 months, is described. A modified plate and screw method of fixation of the lateral masses of the atlas and axis was successfully used in these cases. The technical aspects and merits of the method, wherein a 100% union rate was achieved, with no morbidity, mortality, or instrument fatigue or failure, are presented. The average follow-up period is of 19 months. The technique provided immediate rigid segmental internal fixation, permitting early mobilization with minimal external support. Onlay and interfacetal bone grafts subsequently produced bony fusion. Direct application of screws to the atlas and axis, thus utilizing the firm purchase in their thick and large cortico-cancellous lateral mass, provides a biomechanically strong fixation of the region. Occipito-cervical fusion can be achieved in selected cases by a modification of the method. It appears that such a method of fixation could be useful at least in some complex congenital or traumatic craniovertebral region instability where the conventional methods have failed or are not suitable.

Posterior acrylic surgical fixation of odontoid fractures

Fourteen cases of odontoid fractures had, as primary treatment, a posterior surgical fixation (C1 + C2 + C3 and occiput in some cases) by means of acrylate and stainless steel wires, without waiting for the unpredictable final results of external systems of stabilization. The youngest patient was 20 years old, the oldest 84 years old. No immediate or late neurological complications occurred (follow-up: one year to ten years). All the patients were mobilized early without external fixation. Union of the dens took place in eleven cases, and good stabilization in the remainder. Thirteen patients recovered, one improved. Posterior acrylic fixation is the treatment of choice in cases of odontoid fracture, particularly in elderly patients in whom a solid union rarely is obtained.

Indications and technique for the operative treatment of hypoplastic deformities of the odontoid process

On the basis of four typical cases of congenital hypoplastic deformities of the odontoid process the clinical significance, symptoms, diagnosis and the indications for operative treatment of the malformations are described. It is further shown that these malformations lead to clinical manifestations only when associated with a primarily existing, or a later acquired inadequacy of the ligaments with movement-induced changes in the position of the atlas. The operative treatment recommended involves a special technique for a bilateral dorsal fixation with tibial grafts. By this operative technique a substantial or even completely stable fixation of the atlas can be achieved, in the acute phase by the stability of the tibial grafts and in the long term by the bony fusion which occurs.

Choice of treatment of odontoid fractures

✓ This paper presents a discussion of the diagnosis and treatment of odontoid fractures, based upon the authors' experience with this entity over the last 10 years. Conservative therapy and surgical fusion are compared with respect to efficacy and duration of hospitalization. Arthrodesis is recommended for consideration in the initial treatment of all unstable odontoid fractures.

Posterior atlanto-axial fusion: a new compression clamp for laminar osteosynthesis

A new method of dorsal arthrodesis in patients with atlanto-axial instability of different etiology is described. In three patients solid laminar osteosynthesis C1/C2 was achieved by insertion of an autogenous cortico-cancellous bone graft into the interlaminar space and by a bilateral application of the lately developed metal clamp. The technical principles of the clamp guarantee a permanent pressure on the graft and a solid initial stability in the segment. Additional external fixation and immobilization of the patient are not necessary. Complications as known from other procedures of the atlanto-axial dorsal fusion will be prevented efficiently.

Instrumentation for cervical wire fusion. Technical note

✓ Difficulties encountered in passing the wires for cervical fusions have been significantly diminished by new wire-passing and wire-twisting instruments and the use of very slight flexion at the atlantooccipital interspace, maintained by a threepoint headrest.

Transoral decompression for myelopathy caused by rheumatoid arithritis of the cervical spine. Case report

✓ A case of rheumatoid cervical myelopathy that responded to posterior decompression and fusion is presented. Progression of the disease ultimately required anterior decompression through a transoral approach.

Treatment of fractures of the atlas and axis by wiring without fusion

✓ Fractures and dislocations involving C-1 and C-2 vertebrae have usually been treated by prolonged external immobilization or by internal fixation and fusion. This is a report of 12 patients treated by internal fixation by wiring only. Follow-up studies, up to 4 years, demonstrated healing of the bone and no late neurological sequelae. The advantage of internal fixation in reducing hospitalization and immobilization is accepted. The authors believe that in most instances the addition of bone fusion to the operative procedure is not essential and may increase morbidity.

Acrylic fixation of atlanto-axial dislocations. Technical note

✓ An operative technique using methyl methacrylate (acrylic) and wiring for the treatment of atlanto-axial dislocations is described. Long-term evaluation of a series of patients indicates that this is a safe and effective method of obtaining cervical fixation.

Spinal perineurial and meningeal cysts

Perineurial cysts may be responsible for clinical symptoms and a cure effected by their removal. They do not fill on initial myelography but may fill with Pantopaque some time, days or weeks, after Pantopaque has been instilled into the subarachnoid space. Perineurial cysts arise at the site of the posterior root ganglion. The cyst wall is composed of neural tissue. When initial myelography fails to reveal an adequate cause for the patient's symptoms and signs referable to the caudal nerve roots, then about a millilitre of Pantopaque should be left in the canal for delayed myelography which may later reveal a sacral perineurial cyst or, occasionally, a meningeal cyst. Meningeal diverticula occur proximal to the posterior root ganglia and usually fill on initial myelography. They are in free communication with the subarachnoid space and are rarely in my experience responsible for clinical symptoms. Meningeal diverticula and meningeal cysts appear to represent a continuum. Pantopaque left in the subarachnoid space may convert a meningeal diverticulum into an expanding symptomatic meningeal cyst, as in the case described. Many cases described as perineurial cysts represent abnormally long arachnoidal prolongations over nerve roots or meningeal diverticula. In general, neither of the latter is of pathological significance. Perineurial, like meningeal cysts and diverticula, may be asymptomatic. They should be operated upon only if they produce progressive or disabling symptoms or signs clearly attributable to them. When myelography must be done, and this should be done only as a preliminary to a probable necessary operation, then patient effort should be made to remove the Pantopaque.