Occipitocervical contoured rod stabilization: does it still have a role amidst the modern stabilization techniques?

BACKGROUND

The occipitocervical contoured rod (CR) stabilization for use in craniovertebral junction (CVJ) pathologies is an effective and economical technique of posterior fusion (PF).

AIMS

The various indications for CR in CVJ pathologies are discussed.

SETTINGS AND DESIGN

Retrospective analysis.

MATERIALS AND METHODS

Fifty-four patients (mean age: 31.02+/-13.44 years; male: female ratio=5.75:1) who underwent CR stabilization are included. The majority had congenital atlantoaxial dislocation (AAD; n=50); two had CVJ tuberculosis; one each had rheumatoid arthritis and C2-3 listhesis, respectively. The indications for CR fusion in congenital AAD were associated Chiari 1 malformation (C1M) (n=29); occipitalized C1 arch and/or malformed or deficient C1 or C2 posterior elements (n=9); hypermobile AAD (n=2); and, rotatory AAD (n=3). Contoured rod as a revision procedure was also performed in seven patients. Most patients were in poor grade (18 in Grade III [partial dependence for daily needs] and 15 in Grade IV [total dependence]); 15 patients were in Grade II [independent except for minor deficits] and six in Grade I [no weakness except hyperreflexia or neck pain].

RESULTS

Twenty-four patients improved, 18 stabilized and six deteriorated at a mean follow-up (FU) of 17.78+/-19.75 (2-84) months. Six patients were lost to FU. In 37 patients with a FU of at least three months, stability and bony union could be assessed. Thirty-one of them achieved a bony fusion/stable construct.

CONCLUSIONS

Contoured rod is especially useful for PF in cases of congenital AAD with coexisting CIM, cervical scoliosis, sub-axial instability and/or asymmetrical facet joints. In acquired pathologies with three-column instability, inclusion of joints one level above the affected one by using CR, especially enhances stability.