Total spondylectomy of C2: a new surgical technique.
According to the available sources, no case of total spondylectomy of C2 with preservation of roots, preservation of vertebral arteries and a short fixation without occipitocervical fusion has been so far described in the literature. We decided to perform a radical surgery in a man, now 27 y. o., with solitary metastasis of thyroid adenocarcinoma. In the first step, we applied the posterior surgical approach. The patient was placed prone on a standard operating table with a support of head fixed by adhesive plaster, with the upper cervical spine slightly bent forward. We made a mid-line incision, extending from the external occipital protuberance to the C7 spinous process, controlled bleeding and exposed the C0-C4 section. Subsequently, the entire posterior epistropheus was resected, including most of the pedicles and the entire articular processes for C2-C3 articulation. Both the C2 roots were preserved, however, we had to control quite a profuse bleeding from the venous plexus around the left root. During dissection, the dural sac was damaged in the region of the attachment of the left root, which was treated by suture and covered with Tissucol fibrin sealant. Screws 4.0 mm thick, were inserted into the lateral masses of the atlas after Harms and 4.0mm screws into the C3 and C4 articular processes. On both sides, the screws were connected with 3.2 mm rods, and a transverse stabilizer was then applied to fix the two sides together. Cancellous bone grafts were harvested from the iliac crest and a massive posterolateral and posterior fusion of C1-C4 was performed. The second operation was performed after 21 days. Transoral transmandible approach without tongue splitting was applied. The patient was placed supine on a standard operating table with a support of neck, the head was fixed by adhesive plaster and slightly bent back, and tracheostomy was inserted. An arched incision through the middle of the red lip was made, extending 2 cm straight caudally and arching across the chin and neck, in the midline. On the caudal end we made a transverse inverted T incision. Subsequently, we exposed and osteotomised the mandible using the midline Z-type incision. In order to identify the space between the anterior arch of C1 and the C4 vertebral body, the Synframe retractor was inserted with one blade opening the mouth by pressure on the upper teeth and two blades pressing the tongue caudally. Then an inverted U incision through the mucosa of pharynx was made to identify paravertebral muscles. Caspar retractor was used to separate the muscles and expose C1-C3 laterally, including transversal processes with vertebral arteries. No pathological changes were manifested on the skeleton. First we removed the middle portion of the C2 vertebral body where we did not find any tumour, only sclerotic remodelling. Subsequently, we reamed the lower middle portion of the anterior arch of C1, extracted the dens and cut off the alar ligaments and the apical ligament of dens. The entire dens was then removed. Then we continued on the right side, in the intact part and extracted part of C2 in the region of the atlantoaxial joint, including the rest of the pedicle, and the anterior portion of the transversal process up to the vertebral artery. The posterior part of the transversal process was carefully rotated around the artery and also removed. All parts were extremely hard, sclerotic. The same procedure was followed on the left side where we found a 7 x 10 mm gelatinous greyish tumour in the lateral part of C2 below the atlantoaxial joint. Other parts were again sclerotic. Liquorrhea appeared again from dissection around the C2 root on the left side, the source of which we could not clearly identify. We filled the site of the probable hole with Tissucol fibrin sealant. Between the notch in the lower part of the anterior arch of C1 and the upper end plate of the C3 vertebral body we seated a shaped SynMesh cage with sharp edges providing a very good fixation. No additional fixation was needed. Again we harvested cancellous bone grafts from the iliac crest and placed them on the sides of the cage and at the front between the anterior arch of the atlas and the C3 vertebral body. Subsequently, the muscles were approximated and the mucous tissue of the pharynx repaired. The mandible was fixed by two Miniplate System plates and supported by a dental plate. Total spondylectomy of C2 with preservation of vertebral arteries and roots stabilized only by a short fixation is an extreme surgical procedure suitable only for exceptional cases of young patients with a good bone quality. With regard to potential complications it is of vital importance to consider carefully such operation and consult the proposed therapy with the patient.
Stulík
J
J
Department of Spinal Surgery, University Hospital Motol, Prague.
Kozák
J
J
Sebesta
P
P
Vyskocil
T
T
Kryl
J
J
Pelichovská
M
M
D000230:Adenocarcinoma / Q000556:secondary* / Q000601:surgery*; D000328:Adult; D002574:Cervical Vertebrae / Q000601:surgery*; D006801:Humans; D008297:Male; D019637:Orthopedic Procedures / Q000379:methods*; D013125:Spinal Neoplasms / Q000556:secondary* / Q000601:surgery; D013964:Thyroid Neoplasms / Q000473:pathology