SURGICAL CORRECTION OF SEVERE AND FIXED CHIN-ON-CHEST DEFORMITY

ABSTRACT Objective: To describe a successful surgical treatment for the challenging severe and fixed chin-on-chest deformity due to isolated neck extensor myopathy (INEM). Background data: INEM is an idiopathic cause of dropped head syndrome (DHS) that results in severe cervicothoracic kyphosis, defined as chin-on-chest deformity. The existing literature on surgical management is limited, with outcomes ranging from poor to excellent. INEM may present to the spinal surgeon for consideration of surgical management. Methods: The authors present a technique that uses a staged posterior and anterior approach combined with osteotomies and corpectomy to correct the severe and fixed deformity. A state of the art anterior and posterior instrumentation system was used. Results: At the three-months follow-up, there was good deformity correction and the patient's satisfaction was high, with no neurological deterioration occurring. Conclusions: The technique illustrated in this study represents a successful option to treat this debilitating deformity. More evidence is needed to set up a definitive algorithm for the management of this condition. Level of evidence IV, Case Report.

# 摘要
目的：描述针对孤立性颈伸肌病（isolated neck extensor myopathy, INEM）所致的难治性重度固定性颏胸畸形的成功手术治疗方案。
背景资料：INEM是引发垂头综合征（dropped head syndrome, DHS）的特发性病因，可导致重度颈胸后凸畸形，即颏胸畸形。目前关于该病症手术治疗的相关文献较为有限，手术疗效从较差至优异不等。脊柱外科医师可能会接诊需考虑手术治疗的INEM患者。
方法：本文作者介绍一种分期前后路联合截骨及椎体切除术的术式，以矫正重度固定性畸形，并采用当前前沿的前后路内固定系统完成固定。
结果：术后3个月随访时，畸形矫正效果良好，患者满意度较高，未出现神经功能恶化情况。
结论：本研究展示的术式为治疗此类致残性畸形提供了一种有效的可选方案。目前仍需更多研究证据以确立该病症的标准化诊疗流程。
证据等级：IV级，病例报告。