Multisegmental cervical ossification of the posterior longitudinal ligament: Anterior vs posterior approach

Aims : To determine the surgical approach in patients with multisegmental (four or more segments) OPLL of the cervical spine.
Methods and Materials : Data of 27 patients who had undergone either an anterior (corpectomy with excision of OPLL and interbody fusion=14 patients) or posterior approach (laminectomy=12, laminoplasty=1 patient) for the multisegmental cervical OPLL was analyzed retrospectively. The patients in each group were statistically similar in respect to preoperative factors such as age, duration of symptoms, preoperative modified Japanese orthopedic association score, OPLL thickness, effective canal diameter, and antero-posterior cord compression ratio. The clinical outcome was assessed by the Harsh grading system and recovery rate was assessed by Hirabayashi method.
Results : There was no statistical difference in the outcome, and recovery rate. Nine patients developed complications after anterior approach in contrast to one after posterior approach.
Conclusions : In patients with multisegmental cervical OPLL, there was no significant difference in the short-term recovery rate and outcome between two groups. The immediate postoperative complications were less in patients who had undergone posterior approach. From our analysis, it appears that the posterior approach is probably the preferred method of treatment in a multisegmental OPLL in absence of preoperative kyphosis.

Keywords
cervical spine; laminoplasty; ossification of the posterior longitudinal ligament; spinal instrumentation.