A comparative study of single anterior or posterior approach and one stage combined anterior and posterior approach for isolated ossification of the posterior longitudinal ligament

English Keywords:Ossification of the posterior longitudinal ligament  Surgical approach  Improvement rate of JOA score  Complications

English Abstract:

  【Abstract】 Objectives: To compare the outcomes and complications of single anterior or posterior approach and one stage combined anterior and posterior approach for isolated ossification of the posterior longitudinal ligament(OPLL). Methods: In this study a retrospective review was performed on 69 patients with OPLL admitted to our hospital from June 2000 to June 2009. All those patients had impairment of pyramidal system including: weakness of extremities, gait disturbance, clumsiness of upper extremities, hypermyotonia, deep-tendon hyperreflexia and the positive Hoffman′s sign, and all patients presented with typical isolated OPLL in CT and MRI. According to 3 different operation approaches, all patients were divided into 3 groups: 25 patients(group Ⅰ) experienced anterior cervical decompression and fusion for direct dessect of the ossified ligament, 22 patients(group Ⅱ) experienced posterior unilateral open-door laminoplasty, and 22 patients(group Ⅲ) experienced one stage combined anterior and posterior operation(posterior unilateral laminoplasty followed by anterior cervical decompression and fusion). Incidence of dura mater torn and weakness of lower extremities during or after operation and the improvement rate of the JOA score after operation were observed in this study. Results: The incidence of dura mater torn during operation was 32%, 0% and 4.5% in group Ⅰ, Ⅱ and Ⅲ respectively, and weakness of lower extremities was 24%, 0 and 0 in group Ⅰ, Ⅱ and Ⅲ respectively. Compared with group Ⅰ, the incidences of both dura mater torn and weakness of lower extremities in group Ⅲ were significantly lower(P<0.05). All patients were followed up for more than 1 year(average, 15.3 months). Three months after operation, the improvement rate of JOA sore was (40.0±3.4)%, (32.3±4.5)% and (44.6±5.4)% respectively in three groups, and at final follow-up was (60.8±7.7)%, (52.6±12.1)% and (66.2±8.9)% respectively. Improvement rate of JOA sore in group Ⅲ was significantly higher than that in group Ⅰ and group Ⅱ(P<0.05). Conclusions: One stage combined anterior and posterior approach is effective of low incidence of complication for isolated OPLL, which is superior than single anterior or posterior approach.