Pathogenesis and Prophylaxis of Postlaminectomy Deformity of the Spine after Multiple Level Laminectomy

Abstract

The pathogenesis of postlaminectomy spinal deformity and instability in children was evaluated by reviewing appropriate roentgenographic findings. First, we reviewed spine roentgenograms of patients below 40 years of age who underwent spinal fusion for deformity and instability of the spine developing after a multiple level laminectomy. Two types of deformity were recognized on the roentgenograms: increased mobility between the vertebral bodies and wedging deformity of the ventral aspect of the vertebral bodies. Second, we did a follow-up study of another group of patients who had undergone laminectomy. We found the same two types of deformity in children, but not in adult patients. The incidence of deformity was higher after laminectomies of the cervical or cervicothoracic region than after lumbar laminectomies. Our data suggest that postlaminectomy spinal deformity can develop in children without irradiation or facet injury. The deformity is due to a wedging change in the cartilaginous portion of the vertebral body and to the viscoelasticity of ligaments in children. When treatment of this complication becomes necessary, anterior fusion may be effective in arresting progression. Prophylactic measures against the development of deformity are discussed. Our hypothesis concerning the mechanism of development of this complication supports the rationale of osteoplastic laminar resection and reconstruction instead of laminectomy, particularly in the management of children.

Unilateral hemilaminectomy for patients with intradural extramedullary tumors

“…The anatomical structures removed usually include the spinous process, the laminae, part of the facet complex, the interspinous and supraspinous ligaments, and the ligamentum flavum. It may result in gradually-increasing instability or deformity of the vertebral column (Raimondi et al, 1976;Panjabi and White, 1980;Yasuoka et al, 1981;Alexander, 1985;Reimer and Onofrio, 1985;Ogden et al, 2009). In children, the rate of deformity after laminectomy is up to 88% with 27%-60% of subjects receiving a second fusion operation (de Jonge et al, 2005;Yao et al, 2007).…”

“…Of the spinal cord tumors identified, 69% is non-malignant, and the most common histological types are meningiomas (29%), nerve sheath tumors (24%), and ependymomas (23%) by population-based data available on primary spinal cord (Schellinger et al, 2008). The initial strategy for patients with spinal cord tumors is to surgically extirpate via different approaches, which includes laminectomy (Raimondi et al, 1976;Yasuoka et al, 1981;Alexander, 1985;Reimer and Onofrio, 1985;Lonstein, 1977), hemilaminectomy (Taylor, 1910;Panjabi and White, 1980;Abbott et al, 1992;Öktem et al, 2000;Ogden et al, 2009), partial hemilaminectomy (Yasargil et al, 1991), and osteoblastic laminotomy and osteoplastic laminotomy (Parkinson, 1977;Inoue et al, 1996;Yeh et al, 2001). Although the hemilaminectomy technique is known to neurosurgeons performing spinal surgery, conventional laminectomy has been commonly used for extirpation of spinal tumors.…”

“…Although the hemilaminectomy technique is known to neurosurgeons performing spinal surgery, conventional laminectomy has been commonly used for extirpation of spinal tumors. Clinical studies demonstrated that laminectomy might be associated with a number of postoperative complications, including spinal deformity, instability, epidural fibrosis, and progressive myelopathy (Raimondi et al, 1976;Lonstein, 1977;Yasuoka et al, 1981;Alexander, 1985;Reimer and Onofrio, 1985). Osteoblastic laminotomy and osteoplastic laminotomy remained desirable to rate the above-mentioned complications (Raimondi et al, 1976;Parkinson, 1977;Inoue et al, 1996;Yeh et al, 2001).…”

Spinal Sagittal Malalignment following Surgery for Primary Intramedullary Tumours in Children

“…In children, the incompletely ossified vertebral bodies of both the cervical and thoracic spines offer poor resistance to compressive forces. When under excessive compression, wedge deformity of the vertebral bodies tends to develop, thus initiating or exacerbating kyphotic deformity [25]. On the other hand, the relative contributions of the two posterior elements, osseoligamentous and neuromuscular, in resisting tension differ in the cervical and thoracic spines.…”

“…In the absence of such integrity, the visco-elastically lax posterior intervertebral ligaments and incompletely ossified vertebral bodies are incapable of significant resistance to progressive kyphotic deformity [25, 26]. This is also well demonstrated clinically in various paralytic diseases of the spine.…”