Details

Autor(en) / Beteiligte

• Nishikawa, Misao
• Milhorat, Thomas H.
• Bolognese, Paolo A.
• Kula, Roger W.
• Masamura, Seiya
• Ikuno, Hiromichi

Titel

Fusion in Patients with Occipito-Atlanto-Axial Joint Instability: Management Strategy and Results

Ist Teil von

• Spinal Surgery, 2012, Vol.26(2), pp.211-220

Ort / Verlag

The Japanese Society of Spinal Surgery

Erscheinungsjahr

2012

Link zum Volltext

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• Object : We previously reported that patients with hereditary disorders of connective tissue (HDCT) or post-traumatic condition (PTC) may present with lower brain stem symptoms attributable to occipito-atlantoaxial (OAA) instability. We performed occipito-cervical fusion (OCF) using instrumentation for OAA instability. We examined the factors that influence the outcome and have reported the preliminary results.   Materials and Methods : Osseous structures comprising the cranio-cervical junction were investigated morphometrically using a reconstructed 3D and 2D computed tomography (CT). We detected OAA joint instability in 445 patients with HDCT, PTC, degenerative diseases, cranio−cervical anomalies (CC anomaly), rheumatoid arthritis (RA), and tuberculosis. Surgical indication for OCF was determined on the basis of cranio-cervical traction test. OCF was performed in 250 patients using VERTEX MAXTM or SynapseTM reconstruction system, human fibula allografts, and INFUSE® (rhBMP). We used navigations systems such as the Orbic 3D (intraoperative C-arm based CT system) and the Kolibri navigation system.   Results : Out of 250 patients, 200 patients (80%) showed improvement or resolution of signs and symptoms ; condition of 40 patients (16%) remained unchanged and that of 10 patients (4%) deteriorated. Complete fusion was confirmed in 212 of 250 surgical cases (85%) using reconstructed 2D-CT and dynamic plain cervical X-ray examination. The problems encountered included instrument fracture, increasing instability at the next level after fixation, and incomplete fusion. The rates of improvement of clinical symptoms and complete bony fusion were significantly lower than those with HDCT, CC anomaly, and RA. The rate of development of novel lesions was significantly higher in patients in which fusion was performed at the C3level.   Conclusions : OCF is effective for improving and stabilizing symptoms in patients with OAA joint instability. The cranio-cervical traction test was an important pre-operative procedure for selecting the surgical procedure. Complementary materials for bony fusion should be used in HDCT and RA patients. Although appropriate short segment fusion is necessary, several of our cases required long fusion. Considering the advantages and disadvantages of OAA joint fusion, the surgical indication should be selected carefully.