Two-staged decompression for thoracic paraparesis due to the combined ossification of the posterior longitudinal ligament and the ligamentum flavum: a case report

Study design A case report of ossification of the posterior longitudinal ligament (OPLL) combined with ossification of the ligamentum flavum, or yellow ligament (OYL), in the upper thoracic spine. Objective To describe a rare clinical entity and its management pitfalls in a patient with upper thoracic myelopathy due to combined OPLL and OYL. Methods A 52-year-old woman developed paresthesia and paraparesis of both legs. One month prior to admission she fell and became unable to walk. She was diagnosed as having upper thoracic myelopathy due to combined OPLL and OYL and was treated by two-stage anterior and posterior spinal decompression. Posterior decompression was achieved first by laminoplasty at C3–Th1 and laminectomy of Th2 and Th3. Results After posterior decompression, her symptoms immediately and dramatically improved. However, symptoms recurred after she was able to achieve a sitting or standing position. We then performed anterior decompression at Th2, which again improved her symptoms. At two years post-surgery, she is ambulatory with the use of a cane. Conclusion Upper thoracic myelopathy due to OPLL and OYL was treated by combined 2-staged anterior and posterior decompression. In this case, posterior decompression alone was inadequate to relieve the symptoms of this pathological condition.     

经皮脊柱内镜微创技术治疗胸椎黄韧带骨化症

[目的]介绍经皮内镜技术对胸椎黄韧带骨化导致脊髓病变进行彻底减压治疗经验。[方法]运用经皮脊柱内镜技术通过椎板间入路对2例胸椎黄韧带骨化导致脊髓压迫的患者进行手术减压。精确定位后,建立工作通道,磨除关节突,显露骨化的黄韧带,再将骨化物磨薄,切除。[结果]患者术前神经症状在术后均明显改善,术后复查胸椎CT显示减压效果良好。[结论]经皮内镜技术治疗胸椎黄韧带骨化导致的脊髓病变可在镜下进行直接减压,同时尽量减少创伤和术后不稳,为治疗黄韧带骨化提供一种新的选择。     

Transient paraparesis after laminectomy for thoracic ossification of the posterior longitudinal ligament and ossification of the ligamentum flavum

STUDY DESIGN: Case report. OBJECTIVES: To report a case with thoracic myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF), in which postoperative paralysis occurred after laminectomy and was reversed after an additional posterior instrumented fusion. SETTING: A University Hospital in Japan. CASE REPORT: A 71-year-old woman, with a spastic palsy of both lower extremities, had OPLL and OLF at T10-T11, which pinched the spinal cord anteriorly and posteriorly. She underwent a laminectomy at T10-T11, and no further neurological deterioration was seen immediately after surgery. Over the next 18 h, however, myelopathy worsened, showing severe paraparesis. An additional posterior instrumented fusion at T7-L1 was performed without correction of the kyphosis. After fusion, neurological deficits gradually recovered, despite the presence of residual anterior impingement of spinal cord by the OPLL. CONCLUSIONS: The present case provides evidence for the possibility that laminectomy alone produces postoperative paralysis for combined thoracic OPLL and OLF, and we recommend that a posterior instrumented fusion should be added when posterior decompression is performed for this disorder.     

Pathology of ossification of the posterior longitudinal ligament and ligamentum flavum

Ossification takes place in the posterior longitudinal ligament and ligamentum flavum of the spine under certain conditions of unknown nature. Ossification of these ligaments has the following characteristics: (1) ectopic bone formation occurring within the spinal ligaments; (2) ossification accompanies ligamentous tissue hyperplasia and cell proliferation; (3) before ossification, fibrocartilaginous cell proliferation, calcification and tissue resorption with vascular ingrowth take place sequentially; (4) ossification of the ligament has a specific site of predilection and often occurs in combination with senile ankylosing vertebral hyperostosis (Forestier's disease) or diffuse idiopathic skeletal hyperostosis; and (5) ossification and symptom development are remarkably more frequent in the Japanese population. Recent studies revealed that bone morphogenetic proteins and transforming growth factor-beta played an important role in the matrix hyperplasia and ossification of the spinal ligament, and metabolic and genetic aberration often characterized patients suffering from this disorder.     

椎板薄化分解揭盖法治疗胸椎黄韧带骨化合并脊髓病

目的 探讨椎板薄化分解揭盖法治疗胸椎黄韧带骨化合并脊髓病的疗效.方法 1999年1月至2009年1月,采用椎板薄化分解揭盖减压、植骨融合术治疗胸椎黄韧带骨化合并脊髓病患者126例,男73例,女53例;年龄35～71岁,平均50.2岁.压迫位于上胸段28例,中胸段32例,下胸段66例.采用改良日本骨科协会(Japanese Orthopaedic Association,JOA)下肢运动功能评分、括约肌功能评分以及参照Epstein和Schwall标准评估疗效.摄胸椎正、侧位X线片,行CT及MRI扫描,观察植骨融合情况.结果 116例患者获得随访,随访时间12～96个月,平均49.5个月.术前括约肌功能JOA评分为(1.981±0.543)分,术后为(2.654±0.413)分;术前下肢运动功能JOA评分为(1.196±0.964)分,术后为(3.720±0.709)分;术前及术后比较差异均有统计学意义.按Epstein和Schwall评分标准,优73例,良31例,可9例,差3例;优良率89.7%.术后6例发生脊髓损伤,给予营养神经药物治疗后好转;5例发生脑脊液漏,给予床尾抬高30°,行保守治疗治愈;2例发生切口浅表感染,给予换药处理后愈合.术后6个月111例患者植骨融合;末次随访时,所有患者植骨均获得骨性融合.结论 椎板薄化分解揭盖法对脊髓侵袭小,手术安全性可靠,疗效确切.     

手术治疗胸椎黄韧带骨化症的疗效及其影响因素

目的：探讨胸椎黄韧带骨化症手术治疗的疗效及其影响因素。方法：回顾性总结1986年1月至2003年4月我院采用“揭盖式”胸椎管后壁切除术治疗的135例胸椎黄韧带骨化症患者的资料，随访术后脊髓功能恢复情况，分析患者年龄、术前病程、手术节段与部位、影像学分型及JOA评分等与疗效的关系。结果：135例中82例获得随访，随访率60．7％，平均随访时间5年6个月（2-14年），术后优良率74.4％，有效率92．7％；68．4％的患者在术后2年内恢复停滞，26．3％的患者主诉术后2～5年仍有缓慢恢复；患者的术前病程、年龄、手术节段对术后疗效有显著影响（P〈0．05）；手术节段累及胸腰段者术后疗效较局限于中上胸椎者差。结论：“揭盖式”椎管后壁切除术是治疗胸椎黄韧带骨化症可靠、有效的手术方式。患者术前病程、年龄及手术部位是影响手术疗效的主要因素。     

层揭薄化法减压治疗胸椎黄韧带骨化合并脊髓病

目的介绍层揭薄化法减压治疗胸椎黄韧带骨化合并脊髓病,并探讨其疗效。方法胸椎黄韧带骨化合并脊髓病102例,男63例,女39例;年龄33￣71岁,平均49.7岁。脊髓病位于上胸段33例,中胸段37例,下胸段32例。改良JOA下肢运动功能评分为1.206±0.958。术前存在感觉障碍99例;束带感73例;括约肌功能障碍77例,JOA括约肌功能评分为1.996±0.521。采用层揭法进行减压:第一层,切除椎板背侧皮质;第二层,以关节突关节面为深度标记铲除骨化组织;第三层,高速磨钻打磨使骨化组织呈蛋壳样;第四层,蚕食切除。结果减压2￣4个椎板,平均2.8个。全部病例随访3￣41个月,平均18.9个月。99例感觉障碍者完全恢复69例,部分恢复30例;73例束带感均完全消失;77例括约肌功能障碍者术后JOA评分为2.632±0.407,和术前比较差异有统计学意义(t=15.93,P<0.01)。术后JOA下肢运动功能评分为3.751±0.652,和术前比较差异有统计学意义(t=20.16,P<0.01),运动功能恢复率81.1%,疗效优良率94.1%。结论层揭薄化法减压具有对脊髓侵袭小的优点,术前脊髓神经压迫定位和术中病变椎体的定位是手术成功的前提。     

后路全椎板切除减压并椎弓根内固定治疗胸椎后纵韧带骨化合并黄韧带骨化

目的探讨对胸椎后纵韧带骨化(ossification of posterior longitudinal ligament,OPLL)合并黄韧带骨化(ossification of ligamentum flavum,OLF)患者行后路全椎板切除减压并椎弓根内固定治疗的临床疗效。方法回顾性研究2008年7月~2013年4月,15例胸椎OPLL并OLF患者行后路全椎板切除减压并椎弓根内固定术治疗。分别统计患者一般情况、手术时间、出血量、卧床时间、术后并发症发生率、术前术后日本骨科学会(Japanese Orthopaedic Association,JOA)评分,并进行比较。结果平均随访38.7个月,患者术前、术后3个月及末次随访时JOA评分分别为3.9±1.2、8.1±2.2及10.3±2.5,差异具有统计学意义(P<0.05)。术中1例患者出现脑脊液漏,术后1例患者出现浅表伤口感染,1例患者出现血肿。结论胸椎OPLL并OLF患者行全椎板切除减压并椎弓根内固定术治疗,可获得满意的临床疗效。但该术式容易造成严重脊髓损伤,对术者技巧要求较高。     

Cervical myelopathy resulting from combined ossification of the ligamentum flavum and posterior longitudinal ligament: report of two cases and literature review

Background contextIn the cervical spine, the combination of ossification of the ligamentum flavum (OLF) and ossification of the posterior longitudinal ligament (OPLL) is rarely seen. There have been only four cases reported in the English literature.PurposeWe describe two more cases that exhibited cervical myelopathy resulting from the combination of cervical OLF and OPLL and required surgery. A literature review with a comparative analysis between previous reports and present cases was also performed.Study designCase report and literature review.Patient sampleTwo patients with combined OLF and OPLL.Outcome measuresPreoperative computed tomography, magnetic resonance imaging, and pathological findings from operative specimens were used to confirm the diagnoses.MethodsA 76-year-old man (Case 1) presented with disturbance of gait and fine finger movement. Magnetic resonance imaging showed severe spinal canal stenosis and cord compression at the C3–C4 level. Computed tomography showed OPLL at the C2–C6 levels (segmental type) and OLF at the left C3–C4 level. The patient underwent posterior decompression and OLF resection. A 75-year-old man (Case 2) presented with sensory disturbance and muscle weakness in his bilateral upper extremities and disturbance in fine finger movements. Magnetic resonance imaging showed severe spinal canal stenosis and cord compression at the C2–C3 and C3 levels. Computed tomography showed OPLL at the C3–C7 levels (mixed type) and OLF at the left C2–C3 and C3 levels. The patient also underwent posterior decompression and OLF resection.ResultsIn both cases, histological examination of the surgical specimens showed osseous tissue and enchondral ossification within the ligamentum flavum, and the diagnosis in each case was OLF. After surgery, both patients' symptoms immediately improved, and no recurrence was observed at 2 years after surgery.ConclusionsWe experienced two cases of cervical myelopathy resulting from the combination of OLF and OPLL in the cervical spine. The symptoms of myelopathy were treated successfully by laminectomy and laminoplasty with OLF resection in both cases. The literature review including the present two cases revealed that cervical OLF tended to occur adjacent or close to the margin of cervical OPLL, suggesting that the increased mechanical stress at the junction of OPLL may be a causative factor.     

Posterior decompression with instrumented fusion for thoracic myelopathy caused by ossification of the posterior longitudinal ligament

We evaluated the clinical results of posterior decompression with instrumented fusion (PDF) for thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL). A total of 24 patients underwent PDF, and their surgical outcomes were evaluated by the Japanese Orthopaedic Association (JOA) scores (0–11 points) and by recovery rates calculated at 3, 6, 9 and 12 months after surgery and at a mean final follow-up of 4 years and 5 months. The mean JOA score before surgery was 3.7 points. Although transient paralysis occurred immediately after surgery in one patient (3.8%), all patients showed neurological recovery at the final follow-up with a mean JOA score of 8.0 points and a mean recovery rate of 58.1%. The mean recovery rate at 3, 6, 9 and 12 months after surgery was 36.7, 48.8, 54.0 and 56.8%, respectively. The median time point that the JOA score reached its peak value was 9 months after surgery. No patient chose additional anterior decompression surgery via thoracotomy. The present findings demonstrate that despite persistent anterior impingement of the spinal cord by residual OPLL, PDF can result in considerable neurological recovery with a low risk of postoperative paralysis. Since neurological recovery progresses slowly after PDF, we suggest that additional anterior decompression surgery is not desirable during the early stage of recovery.     

Surgery for thoracic myelopathy caused by ossification of the ligamentum flavum

BACKGROUND: Ossification of the ligamentum flavum overlying the lower thoracic spine frequently produces myelopathy. This study analyzed the postoperative outcomes after decompressive laminectomy for thoracic OLF. METHODS: We retrospectively studied 13 patients (10 male, 3 female; mean age, 58 years; range, 39-69). The mean follow-up duration was 66 months (range, 21-107). All patients had undergone decompressive laminectomy and excision of the OLF. The clinical course was evaluated according to the Frankel grading system and JOA scores. The number of vertebral segments demonstrating OLF, the most frequent level of thoracic cord involvement, and spine lesions coexisting with OLF were determined by MR imaging. RESULTS: By the Frankel system, 7 of 13 patients improved by one grade, whereas the others, classified as grade D, were unchanged after surgery. Using the JOA score, the functional improvement was excellent in 3 patients, good in 4, fair in 2, and unchanged in 4. The number of vertebral segments demonstrating OLF included 4 levels in 2 patients, 3 levels in 2 patients, 2 levels in 5 patients, and 1 level in 4 patients. Ossification of the ligamentum flavum occurred most frequently at the T10/T11 level. Tandem cervical and lumbar lesions were present in 6 patients. CONCLUSIONS: Decompressive laminectomy for excision of OLF resulted in clinical improvement using the Frankel grading system in 7 of 13 patients. In myelopathy patients with OLF, preoperative MR imaging of the entire spine is necessary because other coexisting spinal lesions may be present.     

Surgical outcome of thoracic myelopathy secondary to ossification of ligamentum flavum

ObjectivesThoracic myelopathy secondary to OLF is a rare disease described almost exclusively in Japanese patients. Few series of OLF in South Korean subjects has previously been published. This study is to describe the clinical and radiologic aspects, as well as surgical outcomes in a group of South Korean patients.MethodsA retrospective study of 8 consecutive patients, including 4 men and 4 women (mean age, 55.6 years), was conducted from 2002 to 2005. Diagnosis in each case was established using CT. Magnetic resonance imaging was also performed in every case. All patients treated surgically and pathologic studies were performed. A comparison between the preoperative neurological status and the status at follow-up was done using Japanese Orthopaedic Association (JOA) scoring system.ResultsWalking difficulties were the most common presenting complaint. A picture of spastic paraparesis associated with sphincter dysfunction was the most common finding on initial examination. In each case, CT provided sufficient information to establish a diagnosis of OLF, while magnetic resonance imaging was helpful for showing spinal cord involvement. In most of the patients, OLF was located in the lower thoracic spine (T10–T11). Decompressive laminectomy with excision of the OLF resulted in significant improvement in motor weakness and gait in 5 (2 excellent, 3 good) patients who had short duration and no hyperintense intramedullary lesion of spinal cord on MRI. All patients improved in their gait and spasticity, but 2 patients had persistent sensory deficit.ConclusionOLF is a rare cause of thoracic myelopathy. The frequency appears to have been rarely reported in South Korean subjects. CT with sagittal reconstructions and MRI are helpful for diagnosis and spinal cord involvement. When neurologic symptoms develop, decompressive laminectomy should be done immediately and the surgical outcome is generally good if hyperintense intramedullary signal changes of spinal cord have not yet developed.     

前路减压植骨融合治疗胸椎后纵韧带骨化症

目的：探讨前路减压植骨融合治疗胸椎后纵韧带骨化症(OPLL)的临床疗效和适用范围。方法：1994年6月--2002年11月对20例OPLL患者采用前路减压植骨融合治疗，中胸段9例，下胸段11例；1个节段8例，2个节段6例，3个节段3例，4、5、6个节段各1例。结果：术后5例出现脑脊液漏，14例随访3个月--5年8个月，JOA评分由术前的平均3.4分提高到7．6分，植骨块无塌陷，内固定无松动。结论：前路减压植骨融合治疗胸椎后纵韧带骨化症可以取得满意的治疗结果，但对于广泛的胸椎OPLL或合并其它脊椎韧带骨化时该术式有其局限性。     

Staged spinal cord decompression through posterior approach for thoracic myelopathy caused by ossification of posterior longitudinal ligament.

STUDY DESIGN: Prospective clinical study of the effect of staged elimination of anatomic factors inhibiting posterior shift of the thoracic spinal cord on the degree of posterior shift of the thoracic spinal cord and its significance in augmenting the safety of ossification of posterior longitudinal ligament (OPLL) manipulation in thoracic OPLL myelopathy. OBJECTIVES: To develop a comprehensive method that enables safe and sufficient decompression of the spinal cord for thoracic OPLL myelopathy. SUMMARY OF BACKGROUND DATA: Decompression of the spinal cord by direct manipulations of thoracic OPLLs, via either anterior or posterior approach, caused some iatrogenic catastrophic spinal cord injuries, and methods to prevent such injuries during surgery have not yet been developed. METHODS: Procedures of elimination of anatomic factors inhibiting posterior shift of the thoracic spinal cord were performed in stages at intervals of between 1 month and 11 years depending on patients' neurologic status. The first stage operation consisted of extensive cervicothoracic laminoplastic decompression with or without posterior longitudinal durotomy, and if the decompression were insufficient, measures for OPLL-spinal cord separation with or without OPLL manipulation were added. RESULTS: All 17 patients with thoracic OPLL myelopathy showed improvements of neurology comparable with those with successful anterior approaches after decompression. The mean follow-up period was 42 months (range 6-101 months). Neurologic improvements persisted for the entire follow-up period in all patients except one patient who developed arachnoid cyst compressing the dorsum of the once-decompressed spinal cord 30 months after surgery. CONCLUSIONS: Staged posterior decompression to eliminate anatomic factors inhibiting posterior shift of the thoracic spinal cord is the safest and the most reliable method of spinal cord decompression to treat thoracic OPLL myelopathy, so far. However, long-term results are required before the methods can be established.