CT-based morphological analysis of spinal fractures in patients with diffuse idiopathic skeletal hyperostosis

Purpose

To clarify correlations between spinal fracture and delayed paralysis in patients with diffuse idiopathic skeletal hyperostosis (DISH) using computed tomography (CT) with multiplanar reformatting (CT-MPR). DISH increases susceptibility to unstable spinal fractures, leading to neurological deterioration. The pathomechanism of the neurological injury is unclear.

胸椎后纵韧带骨化的临床特点及治疗策略

目的回顾研究手术治疗胸椎后纵韧带骨化症(OPLL)的临床特点及治疗方法。方法1991至2005年手术治疗胸椎OPLL55例,男19例,女36例;年龄35～73岁,平均51.9岁。均伴有脊髓损害。手术方式包括单纯椎管后壁切除术34例、前方OPLL切除减压术15例以及前后路联合手术6例。结果55例中36例(65.5%)合并胸椎黄韧带骨化(OLF),18例(32.7%)合并颈椎OPLL。单纯发生于上胸椎的OPLL13例(23.6%),中胸椎12例(21.8%),下胸椎及胸腰段17例(30.9%),广泛分布者13例(23.6%)。43例获得随访,平均随访时间47.1个月(6～168个月)。37例神经功能有改善,改善率为76.6%,无改善2例,加重4例。前方入路获随访者13例,其中3例症状加重,余改善率平均为82.9%(42.9%～100%)。后路椎管后壁切除术获随访者25例,1例无改善,1例加重,余改善率平均为72.6%(22.2%～100%)。前后路联合手术获随访5例,1例无改善,余改善率平均为83.9%。结论胸椎OPLL常合并胸椎OLF及颈椎OPLL。上胸椎OPLL合并颈椎管狭窄可一期行颈后路单开门及上胸椎椎管后壁切除术。两个节段以内的OPLL且不合并有造成脊髓压迫的胸椎OLF可行前路OPLL切除减压术,否则行后路椎管后壁切除术。单节段的OPLL合并胸椎OLF可行前后路联合手术。     

Risk factors for delayed diagnosis of spinal fracture associated with diffuse idiopathic skeletal hyperostosis: A nationwide multiinstitution survey

BackgroundPatients with DISH are susceptible to spinal fractures and subsequent neurological impairment, including after minor trauma. However, DISH is often asymptomatic and fractures may have minimal symptoms, which may lead to delayed diagnosis. The purpose of this study was to identify risk factors for delayed diagnosis of spinal fractures in patients with diffuse idiopathic skeletal hyperostosis (DISH).MethodsThe subjects were 285 patients with DISH surgically treated at 18 medical centers from 2005 to 2015. Cause of injury, imaging findings, neurological status at the times of injury and first hospital examination, and the time from injury to diagnosis were recorded. A delayed diagnosis was defined as that made >24 h after injury.ResultsMain causes of injury were minor trauma due to a fall from a standing or sitting position (51%) and high-energy trauma due to a fall from a high place (29%) or a traffic accident (12%). Delayed diagnosis occurred in 115 patients (40%; 35 females, 80 males; mean age 76.0 ± 10.4 years), while 170 (60%; 29 females, 141 males; mean age 74.6 ± 12.8 years) had early diagnosis. Delayed group had a significantly higher rate of minor trauma (n = 73, 63% vs. n = 73, 43%), significantly more Frankel grade E (intact neurological status) cases at the time of injury (n = 79, 69% vs. n = 73, 43%), and greater deterioration of Frankel grade from injury to diagnosis (34% vs. 8%, p < 0.01). In multivariate analysis, a minor trauma fall (OR 2.08; P < 0.05) and Frankel grade E at the time of injury (OR 2.29; P < 0.01) were significantly associated with delayed diagnosis.ConclusionIn patients with DISH, it is important to keep in mind the possibility of spinal fracture, even in a situation in which patient sustained only minor trauma and shows no neurological deficit. This is because delayed diagnosis of spinal fracture can cause subsequent neurological deterioration.     

Clinical and radiological study of ossification of the anterior longitudinal ligament in the cervical spine

Twenty-seven patients with ossification of the anterior longitudinal ligament (OALL) in diffuse idiopathic skeletal hyperostosis (DISH) in the cervical region were diagnosed among 2000 individuals during 10 months and analyzed clinically and radiologically by two neurosurgeons. Sex distribution was 20 men and 7 women with ages ranging from 57 to 82 years (average: 72.3 y.o.). Main signs and symptoms were dysesthesia of the upper extremities, stiff neck, dizziness and dysphagia (33%). Three patients had diabetes mellitus, 14 had hypertension, and 15 had hyperuremia. Ossification of the posterior longitudinal ligament (OPLL) co-existed in 18 patients (66%). Number of vertebral bodies with cervical OALL ranged from 4 to 6 (average: 4.8) and thickness of ossification of the anterior longitudinal ligament was from 2 to 6 (average: 3.1) mm. Originally we divided OALL in the cervical region into 3 types, nodular-type; 16 cases, continuous-type; 7 cases, and mixed-type; 4 cases. Small OPLL can be diagnosed by either cervical CT or myelo-CT. DISH is thought to be a benign clinical entity, but patients with OALL in DISH, accompanied by OPLL and those accompanied by dysphasia are frequently encountered and sometimes may be treated surgically.     

Spinal fractures in patients with ankylosing spinal disorders: a systematic review of the literature on treatment, neurological status and complications

The ankylosed spine is prone to fracture after minor trauma due to its changed biomechanical properties. Although many case reports and small series have been published on patients with ankylosing spondylitis (AS) suffering spine fractures, solid data on clinical outcome are rare. In advanced diffuse idiopathic skeletal hyperostosis (DISH), ossification of spinal ligaments also leads to ankylosis. The prevalence of AS is stable, but since DISH may become more widespread due to its association with age, obesity and type 2 diabetes mellitus, a systematic review of the literature was conducted to increase the current knowledge on treatment, neurological status and complications of patients with preexisting ankylosed spines sustaining spinal trauma. A literature search was performed to obtain all relevant articles concerning the outcome of patients with AS or DISH admitted with spinal fractures. Predefined parameters were extracted from the papers and pooled to study the effect of treatment on neurological status and complications. Ninety-three articles were included, representing 345 AS patients and 55 DISH patients. Most fractures were localized in the cervical spine and resulted from low energy impact. Delayed diagnosis often occurred due to patient and doctor related factors. On admission 67.2% of the AS patients and 40.0% of the DISH patients demonstrated neurologic deficits, while secondary neurological deterioration occurred frequently. Surgical or nonoperative treatment did not alter the neurological prospective for most patients. The complication rate was 51.1% in AS patients and 32.7% in DISH patients. The overall mortality within 3 months after injury was 17.7% in AS and 20.0% in DISH. This review suggests that the clinical outcome of patients with fractures in previously ankylosed spines, due to AS or DISH, is considerably worse compared to the general trauma population. Considering the potential increase in prevalence of DISH cases, this condition may render a new challenge for physicians treating spinal injuries.     

Spinal fractures in patients with diffuse idiopathic skeletal hyperostosis: Clinical characteristics by fracture level

BackgroundDiffuse idiopathic skeletal hyperostosis (DISH) makes the spine prone to unstable fractures with neurological deterioration. This study was conducted to assess clinical and radiographic features of spinal fractures in DISH by the level of spinal injury, and to evaluate the optimal treatment for each level.MethodsA multicenter retrospective study over a 5-year period, including 46 patients (35 males; 11 females) with a mean age of 77.2 ± 9.7 years at the time of injury. By fracture level, there were 7 cervical (15.2%), 25 thoracic (54.3%), and 14 lumbar (30.4%) fractures. We recorded the cause of injury, whether diagnosis was delayed, and neurological status by Frankel grade. Ossification and fracture patterns were assessed by CT-multi-planar reconstruction (MPR).ResultsNeurological status immediately after the cervical-spine injury was C (28.6%) or E (71.4%); after thoracic injury, C (12.0%) or E (88.0%); and after lumbar injury, D (21.4%) or E (78.6%). Inability to walk at admission was more frequent in patients with a spinal-cord injury above the lumbar level (P = .033). Vertebral-body fractures were observed in 14.3% of the cervical injuries, 80.0% of the thoracic injuries, and 50.0% of the lumbar injuries (P = .004). Most patients with a cervical fracture had a disc-level fracture (85.7%). Posterior-column ankylosis was observed in 14.3% of the cervical-fracture group, 72.0% of the thoracic-fracture group, and 78.6% of the lumbar-fracture group (P = .008).ConclusionOssification and fracture patterns in patients with DISH varied distinctly by the level of spinal injury. Intervertebral-disc fractures were frequently observed in the cervical spine. Delayed diagnosis, vertebral-body fracture, and posterior-column ankylosis were observed in the thoracolumbar spine. This study recommends 3 above and 3 below fusion, to avoid instrumentation failure in the fixation of spinal fracture in patients with DISH.     

"涵洞塌陷法"360°脊髓环形减压术治疗胸椎管狭窄症

目的 探讨"涵洞塌陷法"360°脊髓环形减压术治疗胸椎管狭窄症(thoracic spinal stenosis,TSS)的手术方法和疗效.方法 2005年10月至2009年10月,手术治疗26例TSS患者,男17例,女9例;年龄43～67岁,平均56岁.19例为上胸椎(T1-4)椎管狭窄,其中5例为单纯前方后纵韧带骨化(ossification of posterior longitudinal ligament,OPLL)压迫脊髓,14例为前方OPLL合并脊髓后方黄韧带骨化(ossification of ligamentum flavum,OLF)压迫脊髓;7例为中下胸椎(T5～12)椎管狭窄,均为胸脊髓前、后方同时受压,其中5例为胸椎OLF合并OPLL,2例为胸椎OLF合并胸椎间盘突出.术前Frankel分级:B级6例,C级13例,D级7例.采用"涵洞塌陷法"360°脊髓环形减压术:首先从后路应用椎管后壁切除法,去除脊髓后方压迫;然后切除残留的关节突,沿椎弓根斜向内60°至椎体后壁两侧去除椎体后1/3的松质骨,形成一个"涵洞",分离脊髓硬膜前方与椎体后壁和OPLL的粘连后,压塌"涵洞"壁,取出OPLL块,完成脊髓前方的减压.采用椎弓根钉内固定.结果 除2例患者在术后13～27 d有短暂脊髓功能障碍加重外,余24例均恢复.术后随访时间6～30个月,平均14个月.末次随访时26例患者症状均明显改善,Frankel分级:C级2例,D级15例,E级9例.无一例发生双下肢瘫痪.结论 "涵洞塌陷法"360°脊髓环形减压术从后方一次去除胸脊髓前后方压迫,属于直接减压,术后疗效肯定.     

Spinal trauma in DISH and AS: is MRI essential following the detection of vertebral fractures on CT?

BACKGROUNDBoth ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) cause a rigid spine, but through different pathophysiology. Recent data has shown that characteristic fracture patterns may also differ following trauma since the posterior osseous and soft tissue elements are often spared in DISH. CT and MRI are important in diagnosing spine injury, but given the differences between AS and DISH, the utility of obtaining both studies in all patients warrants scrutiny.PURPOSETo assess the prevalence of posterior element injury on CT and MRI in DISH and AS patients with known vertebral body injury detected on CT; to determine whether MRI demonstrates additional injuries in neurologically intact patients presumed to have isolated vertebral body injuries on CT.STUDY DESIGNMulticenter, retrospective, case-control study.PATIENT SAMPLEDISH and AS patients presenting after spine trauma between 2007 and 2017.OUTCOME MEASURESReview of CT and MRI findings at the time of presentation.METHODSOne hundred sixty DISH and 85 AS patients presenting after spine trauma were identified from 2 affiliated academic hospitals serving as level 1 trauma and tertiary referral centers. A diagnosis of DISH or AS was verified by a board-certified emergency radiologist with 3 years of experience. Age, gender, mechanism of injury, fracture type, spine CT and MRI imaging findings, surgical intervention, and neurologic deficit were recorded. The CT and MRI studies were reviewed by the same radiologist for fracture location and type using the AO spine classification. No funding source or conflict of interest was present.RESULTSMedian age was 72 and 79 years old for the AS and DISH groups, respectively. Both were predominantly male (81%) and most presented after a low energy mechanism of injury (74% and 73%). Type C AO spine injuries were seen in 52% of AS patients but only 4% of DISH patients. In patients with known vertebral body injury on CT, additional injury to the posterior elements on CT or MRI in DISH patients was 51% versus 92% in AS patients. However, in patients with an isolated vertebral body fracture on CT and no neurological deficit, MRI identified posterior element injury in only 4/22 (18%) DISH patients compared to 5 of 7 (71%) AS patients. None of the MRI findings in the DISH patients were considered clinically important while all 5 AS patients eventually underwent operative treatment despite having no neurological deficit. Epidural hematoma on MRI was seen in 43% of AS patients as opposed to 5% of DISH patients.CONCLUSIONBased on our small sample size, CT alone may be adequate in DISH patients with isolated vertebral body fractures and no neurologic deficit, but an additional MRI should be considered in the presence of an unclear neurological exam or deficit. MRI should be strongly considered for any AS patient regardless of neurologic status.     

Perioperative complications of anterior cervical decompression with fusion in patients with ossification of the posterior longitudinal ligament: a retrospective, multi-institutional study

BackgroundAnterior decompression with fusion (ADF) for patients with cervical ossification of the posterior longitudinal ligament (OPLL) is reportedly associated with a higher incidence of complications than is laminoplasty. However, the frequency of perioperative complications associated with ADF for cervical OPLL has not been fully established. The purpose of this study was to investigate the incidence of perioperative complications, especially neurological complications, following ADF performed to relieve compressive cervical myelopathy due to cervical OPLL.MethodsStudy participants comprised 150 patients who had undergone ADF for cervical OPLL at 27 institutions between 2005 and 2008. Perioperative—especially neurological—complications occurring within 2 weeks after ADF were analyzed. Preoperative imaging findings, including Cobb angle, between C2 and C7 and occupying ratio of OPLL were investigated. Multivariate analysis with logistic regression was performed to identify independent risk factors for neurological complications.ResultThree patients (2.0 %) showed deterioration of lower-extremity function after ADF. One of the three patients had not regained their preoperative level of function 6 months after surgery. Upper-extremity paresis occurred in 20 patients (13.3 %), five of whom had not returned to preoperative levels 6 months after surgery. Patients with upper-extremity paresis showed significantly higher occupying ratios of OPLL, greater blood loss, longer operation times, fusion of more segments, and higher rates of cerebrospinal fluid leakage than those without paresis. Independent risk factors for upper-extremity paresis were a high occupying ratio of OPLL and large blood loss during surgery.ConclusionsThe incidences of deterioration in upper- and lower-extremity functions were 13.3 % and 2.0 %, respectively. Patients with a high occupying ratio of OPLL are at higher risk of developing neurological deterioration.     

严重颈椎后纵韧带骨化症前路和后路手术比较

目的 探讨前路和后路手术治疗严重颈椎后纵韧带骨化症的适应证选择、疗效及并发症.方法 2004年1月至2006年12月,手术治疗椎管狭窄率大于50%的严重颈椎后纵韧带骨化症患者34例(男29例,女5例,平均57.2岁),前路采用椎体次全切除减压钛网植骨内固定术14例(男12例,女2例),后路采用椎板切除减压侧块螺钉固定术20例(男17例,女3例).比较两种手术方式患者的颈椎管矢状径、颈椎曲度、椎管狭窄率、骨化物分型、骨化物范围、脊髓压迫率等的差异.采用JOA评分评价患者术前、术后神经功能,并计算改善率.结果 影像学结果显示前路手术主要为范围在3个节段以内的局限型和分节型骨化患者,而后路手术主要为范围超过3节段的连续型和混合型骨化患者,骨化物的分型及范围是选择的主要依据.所有患者随访6个月～3年,平均1.5年.前路手术组JOA评分从术前平均(9.3+1.8)分提高至术后平均(14.2±1.3)分,平均改善率62.3%±15.2%;后路手术组JOA评分从术前平均(8.7+1.6)分提高至术后平均(11.4±1.2)分,平均改善率33.5%±12.7%.两组患者疗效差异有统计学意义(P＜0.01).结论 对于骨化范围在3个节段以内的患者,前路手术是安全、有效的治疗方式,而后路手术则适用于范围超过3个节段的严重颈椎后纵韧带骨化症患者.     

Direct medical costs of traumatic thoracolumbar spine fractures

Background?The costs and cost-effectiveness of treatment of thoracolumbar fractures are poorly known.

Methods?We estimated the costs of hospital care and outpatient visits for patients with traumatic thoracolumbar spine fractures.

Results?Stable fractures without neurological deficits were treated nonoperatively and the costs were EUR 5,100. Unstable fractures without neurological deficits were treated either nonoperatively, with an average of 29 hospitalization days and average cost of EUR 12,500 (86% of which represented hospitalization costs), or operatively with 24 hospitalization days and average cost of EUR 19,700 (48% of which represented hospitalization costs and 42% surgery costs). Unstable fractures with neurological deficits were usually operated (average costs EUR 31,900).

Interpretation?For all patients, the costs of hospitalization days were the main cost driver. Although the length of stay for patients with unstable fractures and without neurological deficit who were treated operatively was shorter than for patients treated nonoperatively, the total costs were higher due to the additional costs of surgery. Surgical treatment must therefore be shown to give a better outcome in order to outweigh the costs. Future research should focus on the cost-effectiveness of operative and nonoperative treatment of patients with unstable vertebral fractures who have no neurological deficits, and take indirect costs and quality of life into account.     

Prevalence of pre-existing factors causing spinal cord compression: Is there a difference between patients suffering from cervical spinal cord injury with and without bone injury?

BackgroundRecently, the prevalence of elderly patients suffering from cervical spinal cord injury (CSCI) without bone injury has been increasing in various countries. Pre-existing factors causing spinal cord compression, such as ossification of the posterior longitudinal ligament (OPLL), can increase the risk of CSCI without bone injury. However, no study has compared the prevalence of pre-existing factors between CSCI with and without bone injury. This study aimed to compare the prevalence of pre-existing factors between CSCI with and without bone injury.MethodsIn 168 consecutive patients with CSCI, pre-existing factors including OPLL, posterior spur of the vertebral body, developmental stenosis, disc bulge and calcification of yellow ligament (CYL) were evaluated on imaging studies. The prevalence of each type of pre-existing factors was compared between patients with and without bone injury.ResultsThe prevalence of pre-existing factors in patients without bone injury (86%) was significantly higher than in those with bone injury (20%) (P < 0.001; odds ratio, 23.9). The most common pre-existing factor was OPLL followed by developmental stenosis, posterior spur, disc bulge and CYL in both groups. OPLL, development stenosis and posterior spur were significantly more common in patients without bone injury compared to those with bone injury (P < 0.01).ConclusionsPrevalence of pre-existing factors, such as OPLL, development stenosis and posterior spur was significantly higher in patients without bone injury than in those with bone injury. Thus, these pre-existing factors might be a potential risk of CSCI without bone injury.     

Prevalence and progression of radiographic ossification of the posterior longitudinal ligament and associated factors in the Japanese population: a 3-year follow-up of the ROAD study

Summary

The prevalence of radiographic cervical ossification of the posterior longitudinal ligament (OPLL) in 1,562 Japanese from a population-based cohort was 1.9 %. The presence of OPLL showed a significant association with the femoral neck bone mineral density (BMD), presence of diffuse idiopathic skeletal hyperostosis (DISH) and plasma pentosidine levels. Only one new case of radiographic OPLL was detected, but OPLL progressed in all affected subjects.

Introduction

The purpose of this study was to clarify the prevalence and progression of radiographic OPLL and the associated factors, using the population-based cohort Research on Osteoarthritis/osteoporosis Against Disability (ROAD).

Methods

In the ROAD study, 1,690 participants underwent X-ray examination of the entire spine and both knees. Radiographic OPLL, lumbar spondylosis, knee osteoarthritis and DISH were diagnosed by a single, well-experienced orthopaedic surgeon. An interviewer-administered questionnaire and tests for anthropometric measurements were administered, and the BMDs of the lumbar spine and proximal femur were determined. A new OPLL case was considered if heterotopic ossification in the posterior longitudinal ligament was absent at baseline but present during follow-up. Progression was defined as an increase in the maximum length or width of the ossification at follow-up over that at baseline.

Results

Radiographic OPLL was detected in 30 (17 men, 13 women) of 1,562 individuals who underwent X-ray examination of the cervical spine (prevalence?=?1.9 %). Its prevalence was significantly higher in men than in women (p?=?0.007), but no association with age was observed. In a logistic regression analysis, OPLL showed a significant association with the femoral neck BMD, presence of DISH and plasma pentosidine levels. Only one new case of radiographic OPLL was detected, but OPLL progressed in all affected subjects.

Conclusion

This population-based study clarified the prevalence of radiographic OPLL in the Japanese population as well as its progression. OPLL showed significant association with plasma pentosidine levels, BMD and DISH.     

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.     

Clinical outcome after traumatic spinal fractures in patients with ankylosing spinal disorders compared with control patients

Background contextThe clinical outcome of patients with ankylosing spinal disorders (ASDs) sustaining a spinal fracture has been described to be worse compared with the general trauma population.PurposeTo investigate clinical outcome (neurologic deficits, complications, and mortality) after spinal injury in patients with ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) compared with control patients.Study designRetrospective cohort study.Patient sampleAll patients older than 50 years and admitted with a traumatic spinal fracture to the Emergency Department of the University Medical Center Utrecht, the Netherlands, a regional level-1 trauma center and tertiary referral spine center.Outcome measuresData on comorbidity (Charlson comorbidity score), mechanism of trauma, fracture characteristics, neurologic deficit, complications, and in-hospital mortality were collected from medical records.MethodsWith logistic regression analysis, the association between the presence of an ASD and mortality was investigated in relation to other known risk factors for mortality.ResultsA total of 165 patients met the inclusion criteria; 14 patients were diagnosed with AS (8.5%), 40 patients had DISH (24.2%), and 111 patients were control patients (67.3%). Ankylosing spinal disorder patients were approximately five years older than control patients and predominantly of male gender. The Charlson comorbidity score did not significantly differ among the groups, but Type 2 diabetes mellitus and obesity were more prevalent among DISH patients. In many AS and DISH cases, fractures resulted from low-energy trauma and showed a hyperextension configuration. Patients with AS and DISH were frequently admitted with a neurologic deficit (57.1% and 30.0%, respectively) compared with controls (12.6%; p=.002), which did not improve in the majority of cases. In AS and DISH patients, complication and mortality rates were significantly higher than in controls. Logistic regression analysis showed the parameters age and presence of DISH to be independently, statistically significantly related to mortality.ConclusionsMany patients with AS and DISH showed unstable (hyperextension) fracture configurations and neurologic deficits. Complication and mortality rates were higher in patients with ASD compared with control patients. Increasing age and presence of DISH are predictors of mortality after a spinal fracture.     

Clinical progression of ossification of the ligamentum flavum in thoracic spine: a 10- to 11-year follow-up study

Background

Thoracic ossification of ligamentum flavum (TOLF) can be asymptomatic and progress insidiously. But, long-term follow-up results of clinical progression of TOLF are still unknown.

Methods

The clinical progression of 81 patients with TOLF at our center, followed for 10 to 11 (mean, 10.3) years from May 2010 to November 2021, were analyzed. Among them, 51 patients with thoracic myelopathy were caused by single- or multi-segment TOLF, and received partial TOLF resection (30 patients) or total TOLF resection (21 patients). The remaining 30 patients showed TOLF on imaging examinations, but TOLF was not the responsible compressing factor causing myelopathy and with no TOLF resection. The mJOA score (total 11 scores) and spinal operation were used to evaluate the clinical progression at follow-up.

Results

During the 10- to 11-year follow-up of 81 TOLF patients, 71 (87.7%) had no deterioration of neurological function, and 10 (12.3%) patients had deterioration of neurological function and had another spinal operation, including only 4 (4.9%) suffered thoracic myelopathy caused by the progression of TOLF; 6 (7.4%) for other spinal diseases: 2 (2.5%) had fall damage and acute spinal cord injury at the TOLF level; 2 (2.5%) had thoracic myelopathy caused by ossification of posterior longitudinal ligament (OPLL); 2 (2.5%) had cervical spondylosis and received cervical operation.

Conclusions

Most TOLF (87.7%) patients had no clinical progression and received no reoperations for TOLF in the ten-year dimension (mean, 10.3 years). Narrow spinal canal for TOLF increases the risk of traumatic paraplegia.

     

颈椎病合并颈椎后纵韧带骨化症的前路手术治疗

目的 探讨颈椎病合并颈椎后纵韧带骨化症(OPLL)前路切除减压的方法及其临床效果.方法采用颈椎前路减压治疗颈椎病合并颈椎OPLL患者61例,其中男42例,女19例,平均57岁(45～74岁).术前明确诊断颈椎病合并OPLL者49例,术中发现合并有OPLL者12例.OPLL椎管狭窄率32%～70%,平均52%.神经功能JOA评分术前4～14分,平均9.6分.手术在常规颈前路经椎间隙或椎体次全切除减压的基础上,切除骨化后纵韧带彻底减压.结果 本组41例患者采用前路椎体次全切除减压,6例经椎间隙扩大减压,14例采用椎体次全切除结合经椎间隙减压的手术方式.所有患者随访6个月～3年,平均16个月.术后JOA评分8～16分,平均12.8分,神经功能恢复率25.0%～87.5%,平均65.2%.5例患者术后并发脑脊液漏,经保守治疗后均获得痊愈,无1例出现脊髓功能损害加重.结论 颈椎病合并颈椎OPLL增加了手术难度和风险,在颈椎前路常规减压的基础上再将骨化的后纵韧带切除,保证了前路减压的彻底性,可提高手术治疗效果.     

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。     

侧前方减压治疗胸椎管狭窄

本文报告1987年12月至1995年7月经侧前方减压治疗胸椎管狭窄21例,发病部位多在T_5～T_(12);临床均表现为上运动神经原损害的症状和体征,系间盘退变椎体缘增生11例,DISH(特发性弥漫性脊柱硬化症)6例,OPLL后纵韧带骨化)4例,随诊6～96个月,平均33个月,优良率85.7％。本文对病例选择,手术操作注意事项进行了讨论。     

Long‐Term Follow‐Up of Multilevel Thoracic Ossification of the Posterior Longitudinal Ligament Following Circumferential Decompression via Posterior Approach: A Retrospective Study

ObjectiveTo examine the postoperative progression of multilevel thoracic posterior longitudinal ligament (OPLL) at circumferential decompression (CD) levels and evaluate the long‐term results after CD via the posterior approach.MethodsClinical data from 16 patients with thoracic myelopathy secondary to OPLL who underwent CD at a single center were evaluated retrospectively from 2007 to 2014 and were followed up for more than 60 months. Patients of all sexes and ages were included in the study. Thin‐slice computed tomography scans obtained at the time of surgery and the most recent follow‐up were analyzed. The ossified area was measured on the axial reconstructed scan of the most obvious protrusion of ossification at the CD level. The neurological outcomes were evaluated using modified Japanese Orthopaedic Association (JOA) scores and Hirabayashi recovery rates (HRRs). Continuous variables were presented as the mean ± standard deviation and were analyzed using the Student''s t‐test, while categorical variables were tested using Fisher''s exact test.ResultsAmong all patients, the most predominant type was the mixed type (9/16, 56.3%), while the circumscribed type was only found in two patients (12.5%), and the continuous type was found in five patients (31.2%). Six cases were associated with ossification of the ligamentum flavum, and two cases were combined with cervical OPLL. The OPLL area at the CD level increased in all patients. The mean follow‐up period was 5.5 ± 0.92 years (range 5–8 years). The mean area of ossification increased from 35.63 ± 39.23 mm² at the time of surgery to 99.94 ± 65.39 mm² at the last follow‐up visit (P < 0.01). There was no internal fixation disorder on any computed tomography scan after the operation. The average JOA score of all patients improved from 4.2 ± 2.2 points before surgery to 8.4 ± 2.6 points at the final follow‐up (P < 0.01). The overall HRR was 61.8%. None of the patients exhibited any neurological deterioration due to OPLL progression. One patient developed a severe gait disturbance due to worsening lumbar canal stenosis, an unrelated cause, but the other 15 experienced gait disturbance improvements.ConclusionsAccording to the long‐term follow‐up results, although OPLL progression did not decrease or stop after removing the OPLL mass, CD is a safe and effective procedure that can provide adequate reserve ventral space to cope with postoperative OPLL progression.