In 2006, our hospital improved and began to use cervical expansive open-door laminoplasty preserving the unilateral ligament with muscle complex.The effect of recent follow-up, postoperative complications and their effects on posterior cervical muscle volume were also studied.However, there are few reports about medium and long-term follow-up.

Expansive laminoplasty of posterior cervical canal has been widely used for the treatment of cervical spondylotic myelopathy with cervical spinal stenosis and ossification of the posterior longitudinal ligament since Hirabayashi et al. described it in the 1970s. Traditional single-door surgery requires extensive dissection of both paravertebral muscles and ligaments, and resect part of the spinous process. Postoperative complications (axial neck pain, stiffness, cervical kyphosis, reduced range of motion, etc.) are also related to that in degree. In order to reduce the damage to the posterior cervical structure and reduce the associated complications, in the 1990s, Yoshihiko Oshima et al. introduced the expansive laminoplasty of the spinal canal with one side of the posterior ligamentwith muscle complex attached to the spinous process. In 2006, our hospital improved and began to use cervical expansive open-door laminoplasty preserving the unilateral ligament with muscle complex.The effect of recent follow-up, postoperative complications and their effects on posterior cervical muscle volume were also studied.However, there are few reports about medium and long-term follow-up.

Inclusion Criteria:

• From 2006 to 2018, the patients admitted to the orthopedic department of our hospital for posterior cervical open-door expansive spinal canal laminoplasty with one side muscle-ligament complex reserved.Complete preoperative and postoperative diagnosis and treatment data of our hospital were available, and the follow-up time was ≥2 years.

Exclusion Criteria:

• Patients with incomplete preoperative and postoperative diagnosis and treatment data or less than 2 years of follow-up

From 2006 to 2018, the patients admitted to the orthopedic department of our hospital for posterior cervical open-door expansive spinal canal laminoplasty with one side muscle-ligament complex reserved.