Ventrale Stabilisation einer atlantoaxialen Subluxation mittels Schrauben und Polymethylmetacrylat bei einem Miniatur-Yorkshire-Terrier

Zusammenfassung

Ein 6 Monate alter, weiblicher 1,1 kg schwerer Miniatur-Yorkshire-Terrier wurde aufgrund einer Tetraparese vorgestellt. Auf laterolateralen Röntgenbildern fiel ein vergrößerter Abstand zwischen Processus spinosus des Axis und Arcus dorsalis atlantis bei deutlicher kraniodorsaler Verlagerung und Rotation des kranialen Axiskörpers in Relation zum Atlas auf. Computertomografisch bestätigte sich eine kraniodorsale Verlagerung des kranialen Axis in Relation zum ventralen Atlasbogen im Sinne einer atlantoaxialen Subluxation mit einem nicht fusioniertem Dens axis. Zunächst wurde chirurgisch mit einer dorsalen Muskelnahttechnik versucht, eine entsprechende Reduktion der Subluxation zu erzielen. Da sich die Reduktion röntgenologisch wie auch klinisch als suboptimal erwies, erfolgte eine ventrale Stabilisation mithilfe von 4 1,5-mm-Schrauben in Axis und Atlas sowie Polymethylmetacrylat. Röntgenologisch zeigte sich eine zufriedenstellende Reposition. Der Hund erhielt für 6 Wochen einen stützenden Halsverband. Es kam zu einer progredienten Besserung der neurologischen Symptomatik bis hin zur Symptomfreiheit über bisher 37 Monate.

Abstract

A 6-month-old female Miniature Yorkshire Terrier with a bodyweight of 1.1 kg was presented due to non-ambulatory tetraparesis. Latero-lateral radiographs showed an increased space between the spinal process of the axis and the dorsal arch of the atlas, with craniodorsal displacement and rotation of the body of the axis in relation to the atlas. Computed tomography also revealed a craniodorsal displacement of the axis in relation to the atlas with an unfusioned dens. Initially, a dorsal surgical approach was chosen and an intermuscular suture pattern was used attempting to achieve reduction of the subluxation. Radiographically and clinically the result however was not acceptable. In a second surgery, a ventral stabilization technique (using 4 1.5 mm screws in atlas and axis with polymethylmetacrylate) was performed. The achieved repositioning was considered acceptable. The dog was provided with a cervical bandage for 6 weeks. Clinically, the patient improved progressively and remains free of clinical signs up to the time of manuscript preparation, 37 months post-operatively.

Schlüsselwörter

Atlantoaxiale Instabilität - Miniaturrasse - chirurgische Therapie - Komplikationen - ventrale Fixierung

Key words

Atlantoaxial instability - miniature breed - surgical therapy - complications - ventral fixation

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