To evaluate the efficacy of unilateral open-door laminoplasty with reserved bilateral semispinalis for the treatment of multi-level cervical diseases.

A retrospective study of prospectively collected data from hospital was conducted. From January 2013 to December 2015, thirty-three patients with multi-level cervical disease underwent C₃-C₆ unilateral open-door laminoplasty with reserved bilateral semispinalis. There were 19 males and 14 females with average age 57.22±10.75 years (range 35-75 years). Moreover, 32 patients with multi-level cervical disease underwent unilateral open-door laminoplasty with only reserved supraspinal ligamentum, and 35 underwent C₃-C₇ traditional open-door laminoplasty at the same time. The demographics, operation duration, blood loss volume, cervical curvature, range of motion, axial symptoms, visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) score, the neck disability index (NDI) and complications were recorded and analyzed at preoperation, postoperation and at final follow-up.

The demographics, cervical curvature and range of motion at preoperation, operation duration and blood loss were not significantly difference among three groups (P>0.05). Cervical curvature and range of motion of traditional open-door laminoplasty were 34.38°±7.96° and 11.89°±7.70° at final follow-up (P<0.05). Cervical curvature and range of motion of unilateral open-door laminoplasty with reserved bilateral semispinalis were 38.41°±7.33° and 14.60°±8.56°, and unilateral open-door laminoplasty with only reserved supraspinal ligamentum were 37.63°±4.91°and 14.34°±8.02°. There were significant differences among these 3 groups (P<0.05). JOA and NDI score of three groups were significantly improved at final follow-up (P<0.05). VAS of reserved bilateral semispinalis and reserved supraspinal ligamentum of unilateral open-door laminoplasty were significantly improved at final follow-up (P<0.05). JOA and recovery rate of three groups had no significant difference at final follow-up (P>0.05), while VAS score, NDI score were significantly different (P<0.05). In particular, VAS and NDI of unilateral open-door laminoplasty with reserved bilateral semispinalis were better than other groups. Early pain was reported in each patients. Two patients (6%) with axial symptom was present in unilateral open-door laminoplasty with reserved bilateral semispinalis, 5 patients (16%) in unilateral open-door laminoplasty with only reserved supraspinal ligamentum and 12 patients (34%) in traditional open-door laminoplasty. There were significantly difference among these groups (P<0.05). One patient with C₅ nerve root palsy was reported in unilateral open-door laminoplasty with reserved bilateral semispinalis and unilateral open-door laminoplasty with only reserved supraspinal ligamentum, and two patients in traditional open-door laminoplasty. No cerebrospinal fluid leakage, spinal cord injury, door-hinge fracture, infection, implant loosening or breakage and other complications were observed in each groups.

Unilateral open-door laminoplasty with reserved bilateral semispinalis is an effective technique in treating multi-level cervical disease. The technique not only guaranteed to have good recovery of neurological functional and to maintain cervical curvature and range of motion, but also contributed to decrease the occurrence of postoperative axial symptom.

Cervical spondylosis; Ossification of posterior longitudinal ligament; Spinal stenosis; Treatment outcome