Neurospine.  2021 Dec;18(4):749-757. 10.14245/ns.2142792.396.

Surgical and Functional Outcomes of Expansive Open-Door Laminoplasty for Patients With Mild Kyphotic Cervical Alignment

• Nagoshi N
• Nori S
• Tsuji O
• Suzuki S
• Okada E
• Yagi M
• Nakamura M
• Matsumoto M
• Watanabe K

• KMID: 2523972
• DOI: http://doi.org/10.14245/ns.2142792.396

Abstract

Objective
To evaluate the cervical dynamics, neurological function, pain, and quality of life in patients with mild cervical kyphotic alignment who underwent expansive unilateral open-door laminoplasty (ELAP).
Methods
In this retrospective single-center study, we reviewed the surgical outcomes of 80 patients with cervical spondylotic myelopathy who were followed for at least 2 years. The patients were categorized into the preoperative kyphotic group (C2–7 angle < 0°) and nonkyphotic group (angle ≥ 0°). We compared clinical information, radiographic parameters, Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) scores, and cervical Japanese Orthopaedic Association (JOA) scores between the groups.
Results
The kyphotic and nonkyphotic groups comprised 17 and 63 patients, respectively. The preoperative C2–7 angles were -3.7° in the kyphotic group and 15.4° in the nonkyphotic group (p < 0.01). In the kyphotic group, kyphotic alignment improved to lordosis at the final follow-up (2.6°, p = 0.01). The preoperative (16.4° vs. 24.1°, p < 0.01) and finalfollow-up (17.8° vs. 24.5°, p < 0.01) C7 slopes were significantly smaller in the kyphotic group. ELAP reduced pain in the arms or hands (p = 0.02) and improved the JOA scores (p < 0.01) in the kyphotic group. Patient-reported outcomes assessed using the JOACMEQ showed comparable effective rates in both groups.
Conclusion
Patients with mild cervical kyphosis showed smaller C7 slopes as a compensatory mechanism. Kyphotic angles significantly improved to lordosis after ELAP, resulting in favorable clinical outcomes. ELAP is a useful surgical option for patients even if they present mild kyphotic cervical angles.

Keyword

Cervical spondylotic myelopathy; Expansive unilateral open-door laminoplasty; Kyphotic cervical alignment