Can C3 Laminectomy Reduce Interlaminar Bony Fusion and Preserve the Range of Motion After Cervical Laminoplasty?

STUDY

DESIGN

Retrospective comparative study.

OBJECTIVE

To investigate whether the resection of C3 lamina during cervical laminoplasty can prevent C2-C4 interlaminar bony fusion and preserve the range of motion (ROM) postoperatively.

SUMMARY OF BACKGROUND DATA: Interlaminar bony fusion is a common complication after cervical laminoplasty, especially in the C2-C4. Laminectomy, rather than laminoplasty, of C3 has been recently introduced. Its advantages include minimizing muscle detachment at C2 and reducing postoperative neck pain.

METHODS

A total of 59 patients with cervical spondylotic myelopathy that involved three or more levels, including C3, were consecutively treated with laminoplasty and followed up for more than 3 years after surgery. The first 45 patients underwent open-door laminoplasty at C3 (Lp group) and the subsequent 14 patients underwent laminectomy at C3 rather than laminoplasty (Ln group). The Lp group was further divided into two subgroups based on the development of interlaminar bony fusion at C2-C3 and/or C3-C4: Lp-NF (nonfusion) and Lp-F (fusion) groups. Clinical outcomes and radiographic parameters were assessed pre- and postoperatively.

RESULTS

Nineteen out of 45 patients who underwent laminoplasty demonstrated fusion at 3-year follow up. Fusion developed more commonly in those patients who had a smaller preoperative ROM at C2-C4 segments (Lp-F 14.3° ± 6.9° vs. Lp-NF 21.4° ± 5.3°, P = 0.013). The neck disability index (range, 13.4 ± 7.3 to 6.3 ± 5.2, P < 0.001), visual analog scale for neck pain (range, 2.5 ± 1.7 to 0.9 ± 1.3, P = 0.027), Japanese Orthopedic Association (JOA) score (range, 14.3 ± 1.9 to 16.0 ± 2.4, P < 0.001), and JOA recovery rate (63.4 ± 19.8%) in the Ln group improved postoperatively; however, there was no significant difference in the improvement of these clinical outcomes among all three groups. Postoperative cervical ROM was significantly reduced in all groups; however, the extent of reduction was significantly smaller in the Ln group (10.5°; range, 44.2° ± 9.1° to 33.7 ± 6.0°) than in the Lp-NF (15.1°; range, 45.4° ± 8.5° to 30.3° ± 7.4°) or Lp-F (18.2°; range, 39.6° ± 9.3° to 21.4° ± 10.3°) groups (P < 0.05).

CONCLUSION

C3 laminectomy with laminoplasty can prevent interlaminar bony fusion at C2-C4 and, ultimately, result in better preservation of cervical ROM than C3 laminoplasty. Furthermore, it yields similar clinical outcomes when compared with C3 laminoplasty.

LEVEL OF EVIDENCE: 3.