Minimum 5-year Follow-up Results for Occipitocervical Fusion Using the Screw-Rod System in Craniocervical Instability

Clin Spine Surg. 2017 Jun;30(5):E628-E632. doi: 10.1097/BSD.0000000000000199.


Study design: Retrospective clinical study.

Objective: To evaluate the clinical outcome of patients who had undergone occipitocervical (OC) fusion using pedicle screws and rods over a minimum 5-year follow-up.

Summary of background data: Few studies have evaluated occipitocervical (OC) fusion using pedicle screws and rods for long-term follow-up.

Methods: Twenty-seven consecutive patients treated underwent posterior OC fusion using pedicle screws and rods over a minimum 5-year follow-up. The Modified McCormick scale to grade a patient's functional status and the Japanese Orthopaedic Association (JOA) scoring system were used to evaluate preoperative and postoperative neurological function. We assessed fusion by both direct and indirect evidence; bony trabeculae at the graft-recipient interface on lateral cervical radiographs and sagittal computed tomography reconstruction was considered direct evidence of union.

Results: The mean follow-up period was 7.2 years (5-14 y). JOA scores were 8.1±3.8 before surgery and 11.7±3.7 at the final follow-up. The recovery rate calculated from the JOA scores was 42.0±30.0%. Functional status did improve at least 1 grade according to the modified McCormick scale in 18 patients (66.7%). There was no deterioration at the final follow-up.There were postoperative implant-related complications in 8 patients (29.6%): loosening of pedicle screws in 2, rod breakage in 2, plate breakage in 1, screw breakage in 1, pullout of pedicle screws in 1, and wiring induced myelopathy in 1 patient. The average duration between surgery and implant failure was 31.2 months (12-60 mo) except for 2.

Conclusions: Sufficient bone grafting, proper decortication of the bone bed, using thicker and high stiffness rods, and ultra-high molecular weight polyethylene tape as a fixation or reinforcement of implant may help prevent implant failure.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Cervical Vertebrae / diagnostic imaging
  • Cervical Vertebrae / surgery*
  • Child, Preschool
  • Female
  • Follow-Up Studies
  • Humans
  • Joint Instability / diagnostic imaging
  • Joint Instability / surgery*
  • Male
  • Middle Aged
  • Occipital Bone / diagnostic imaging
  • Occipital Bone / surgery*
  • Pedicle Screws*
  • Postoperative Complications / etiology
  • Reoperation
  • Spinal Fusion*