Late-onset spinal deformities in children treated by laminectomy and radiation therapy for malignant tumours

This is a retrospective study of 76 children who had had malignant tumours treated with laminectomy or laminoplasty and/or radiation therapy affecting the spine. Spinal tumours in children are extremely rare. However, their treatment can result in progressive spinal deformity. Radiation therapy affecting the growing spine can lead to asymmetric vertebral growth, causing kyphosis and/or scoliosis. These spinal deformities pose one of the most challenging problems for the spine surgeon. The aim of this article is to describe late-onset post-laminectomy/post-radiation spinal deformities and to evaluate the results of their treatment. Seventy-six children, with a mean age of 4 years and 7 months (range, 2 months to 16 years), underwent surgical removal of malignant tumours, between 1961 and 1995. Sixty-seven of them developed post-laminectomy/post-radiation spinal deformity. Conservative treatment consisted of bracing and corrective plaster casts. In 46 cases the deformity was treated surgically. A distraction plaster cast was used as preoperative preparation in the more severe and rigid curves, with or without neurological impairment. Surgery consisted of combined anterior and posterior fusion in 39 cases and posterior fusion in seven cases. Posterior instrumentation was used in 38 cases. The mean follow-up period was 6 years and 7 months (range, 9 months to 20 years and 2 months). Nine children did not develop deformity following the primary tumour treatment. One of them underwent laminectomy with posterolateral fusion and eight had laminoplasty combined with external immobilisation. Forty-six children developed iatrogenic kyphosis and underwent surgical correction from a mean of 75° pre-correction to a mean of 32°. The mean scoliotic angle correction was 66° preoperatively to 34° postoperatively. At follow-up, the mean correction loss was 7° in the sagittal plane and 5° in the coronal plane. Preoperative distraction plaster cast treatment resulted in a correction of 39% in kyphosis and of 58% in scoliosis, and in a partial or complete recovery of neurological deficits in all but one patient. In severe and rigid curves that develop following treatment of paediatric spinal tumours, preoperative application of a distraction plaster cast can reduce deformity and facilitate surgical correction. Furthermore, in the case of pure bony compression of the spinal cord due to the apical vertebra of the deformity, treatment with the distraction plaster can result in recovery from the neurological impairment. The prevention of post-laminectomy/post-radiation spine deformities is emphasised. Rigid external immobilisation for a period of 4 months in the cervical spine and of 6 months in the thoracic spine is recommended after both laminoplasty and laminectomy with posterolateral fusion.The research was carried out at Saint Vincent de Paul Hospital, Department of Pediatric Orthopaedic Surgery, Paris     

Clinical analysis of thoracic ossified ligamentum flavum without ventral compressive lesion

The aim of this study was to analyze the clinical characteristics of thoracic ossified ligamentum flavum (OLF) and to elucidate prognostic factors as well as effective surgical treatment modality. The authors analyzed 106 thoracic OLF cases retrospectively from January 1999 to December 2008. The operative (n = 40) and the non-operative group (n = 66) were diagnosed by magnetic resonance imaging (MRI) and/or computed tomography (CT) imaging. We excluded cases exhibiting ventral compressive lesions causing subarachnoid space effacement in thoracic vertebrae as well as those with a coexisting cervical compressive myelopathy. Those in the operative group were treated with decompressive laminectomy as well as resection of OLF. The preoperative neurologic status and postoperative outcomes of patients, as indicated by their modified Japanese Orthopedic Association (mJOA) scores and recovery rate (RR), Modic changes, the axial (fused or non-fused) and sagittal (omega or beak) configurations of OLF, and the ratios of the cross-sectional area (CSA) and anteroposterior diameter (APD) of the most compressed level were studied. The most commonly affected segment was the T10–11 vertebral body level (n = 49, 27.1%) and the least affected segment was the T7–8 level (n = 1, 0.6%). The ratios of the CSA in non-fused and fused types were 77.3 and 59.3% (p < 0.001). When Modic changes were present with OLF, initial mJOA score was found to be significantly lower than those without Modic change (7.62 vs. 9.09, p = 0.033). Neurological status improved after decompressive laminectomy without fusion (preoperative vs. last mJOA; 7.1 ± 2.01 vs. 8.57 ± 1.91, p < 0.001). However, one patient exhibited transient deterioration of her neurological status after surgery. In the axial configuration, fused-type OLF revealed a significant risk for a decreased postoperative mJOA score (0–7, severe and moderate) (Odds ratio: 5.54, χ² = 4.41, p = 0.036, 95% CI: 1.014–30.256). The results indicated that the new categorization of axial-type of OLF is a helpful predictor of postoperative patient outcome and fused type was related with poor prognosis. In OLF cases free from ventral lesions compressing the spinal cord, decompressive laminectomy is enough for successful surgical outcome. Therefore, early surgical treatment will be considered in cases with fused-type OLF compressing spinal cord even though they do not have myelopathic symptoms.     

模拟后路椎间盘镜下腰椎间盘摘除术与传统术式治疗腰椎间盘突出症对腰椎生物力学稳定性的影响

目的探讨后路椎间盘镜下腰椎间盘摘除术(MED)及传统开放腰椎间盘摘除术对腰椎生物力学稳定性的影响。方法选用6具新鲜尸体脊柱标本,模拟后路腰椎间盘摘除的不同术式,依次对标本腰3～4间隙进行处理,共设计5种减压情况:MED、半椎板切除、半椎板切除并下关节突1/2切除、半椎板切除并下关节突全部切除和全椎板切除髓核摘除术。在力学实验机上分别对实验标本进行前屈/后伸、左/右侧屈及左/右轴向旋转运动,测量不同运动的最大范围。结果模拟MED手术脊柱标本向各个方向的运动与正常对照组比较差异无统计学意义(P>0.05);半椎板切除术、半椎板切除并下关节突1/2切除后,标本向各个方向的运动除半椎板切除并下关节突1/2切除后右侧旋转外与正常对照组差异无统计学意义(P>0.05),半椎板切除并下关节突全部切除后,标本向各个方向运动与正常对照组比较差异均有统计学意义(P<0.05,右侧旋转P<0.01);模拟全椎板切除标本向各个方向的运动与正常对照组比较差异均有统计学意义(P<0.01)。结论MED手术对脊柱破坏性较小,对稳定性无影响,而半椎板并小关节切除则破坏了稳定性。     

预防硬膜外瘢痕粘连的实验研究

目的通过动物实验观察几丁糖对预防椎板切除术后硬膜瘢痕粘连的作用。方法24只成年山羊行腰2腰4短节段椎弓根钉系统固定及取自体髂骨行后外侧植骨融合术,腰3水平全椎板切除,切除口约3cm×1.5cm,腰3硬膜外分别放置几丁糖或空白对照各12只。于术后24周进行大体形态、组织学观察,并进行硬膜外瘢痕粘连程度分级。结果几丁糖组硬膜与瘢痕无明显粘连,空白对照组硬膜与瘢痕紧密粘连。结论几丁糖能有效地预防椎板切除术后硬膜外瘢痕粘连。     

医用自交联透明质酸钠凝胶预防兔硬膜外粘连的安全性研究

目的利用体感诱发电位及运动功能评分,评价医用自交联透明质酸钠凝胶预防椎板切除术后硬膜外粘连的安全性。方法将L5全椎板切除的新西兰兔24只随机分为4组,A组为对照组:术区生理盐水冲洗后关闭切口;B组、C组、D组均为实验组:均在术区硬脊膜暴露区覆盖医用自交联透明质酸钠凝胶,而覆盖剂量各不相同,分别为0.5、0.75和1.0ml。分别于麻醉后,椎板切除术后,闭合手术切口之后,术后8周这4个时间点进行体感诱发电位监测并记录潜伏期值。并分别于术前,术后1d,术后8周对各组动物进行后肢运动功能评分。结果麻醉后和椎板切除术后各组潜伏期值无统计学差异(P0.05)。在关闭切口后测定各组的潜伏期值显示:A组和B组潜伏期值均无延迟(P0.05),C组和D组潜伏期值出现明显延迟(P0.05)。在术后8周复测各组潜伏期值,均处于正常范围(P0.05)。运动功能评分结果:术前所有动物评分均正常。在术后1d,A组和B组动物的评分仍然正常,C组和D组的动物评分下降。在术后8周,各组动物的运动功能评分均再次正常。结论体感诱发电位是测定脊髓损伤的敏感指标;椎板切除术后局部覆盖预防粘连剂有剂量的要求,0.5ml的医用自交联透明质酸钠凝胶不会对该动物模型的脊髓的电生理功能及后肢运动功能产生影响。     

Selective blocking laminoplasty in cervical laminectomy and fusion to prevent postoperative C5 palsy

BACKGROUND CONTEXT

Cervical laminectomy and fusion (CLF) is a common surgical option for multilevel cord compression. Postoperative C5 palsy occurrence after CLF has been a vexing problem for spine physicians. The posterior shift of the cord following laminectomy has been implicated as a major factor for postoperative C5 palsy, but attempts by spine surgeons to mitigate excessive shift while providing sufficient decompression have not been well reported.

Bloqueo ecoguiado bajo el músculo multífido para el dolor postoperatorio tras cirugía de columna lumbar: serie prospectiva de casos

We describe a series of 15 patients scheduled for single level lumbar spine decompression with instrumentation receiving ultrasound (US) guided submultifidus block (SMFB). In this series, injections of local anesthetic deep to the multifidus muscle provided reliable block of dorsal rami of spinal nerves at multiple levels. With US, the multifidus muscle can be identified both in axial and parasagittal planes. Needle tip is easily visualized beneath the multifidus and medial to the transverse process. Good quality analgesia was documented by pain scores. There were no adverse events. Further studies are needed to compare this nerve block with routine multimodal analgesia or with the recently described thoracolumbar interfascial plane block to compare safety and analgesic efficacy.