Symptomatic retro-odontoid pseudotumor causing calcium pyrophosphate dihydrate deposition combined with multilevel cervical spondylotic myelopathy

IntroductionSymptomatic retro-odontoid pseudotumor (ROP) caused by cervical compression and myelopathy is rare. Pathological diagnosis is recommended for differential diagnosis including the following: inflammatory disease, primary bone tumor, metastatic disease and calcium pyrophosphate dihydrate deposition (CPPD) also known as “crowned dens syndrome”. The authors report a rare case of ROP caused by CPPD deposition combined with multilevel cervical spondylotic myelopathy (MCSM) which was treated by tumor resectioning using a transoral approach combined with posterior decompression and fusion.Case presentationA 66-year-old male presented with progressive neck pain and spastic gait with no history of trauma. Radiographic imaging revealed degenerative change involving the atlanto-axial and atlanto-occipital joints with calcified enhancing soft tissue around the odontoid process causing cord compression and cervical instability at the C1-C2 level combined with MCSM and spinal cord compression at C3 to C7. Microscopic assisted transoral tumor resection combined with posterior decompression and fusion was performed at the occiput to T2. The pathology report describes a rhomboid-shaped crystal caused by calcium pyrophosphate dihydrate deposition (CPPD) disease. At the 6-month follow-up following the operation, the patient's neck pain and spastic gait were improved compared to the preoperative examination.DiscussionCervical compression and myelopathy from ROP causing CPPD combined with MCSM is rare. Pathology diagnosis and surgical management are highly recommended.ConclusionIn this case, a combined surgical approach: tumor resection using a transoral approach and a posterior approach for decompression and fusion at occiput to T2 was an effective option for this condition.     

Hypertrophic dens resulting in cervical myelopathy: histologic features of the hypertrophic dens

STUDY DESIGN: A case report of a 43-year-old woman who had hypertrophic dens in the developmentally narrow atlas ring that resulted in cervical myelopathy. OBJECTIVES: To present histologic findings of the hypertrophic dens, which was excised en block the transoral approach, and to discuss the pathogenesis of the hypertrophic change of the dens. SUMMARY OF BACKGROUND DATA: Few cases have been reported of cervical myelopathy associated with hypertrophic dens, and there have been no previous reports describing the histologic features of hypertrophic dens. METHODS: Clinical data were reviewed from the patient's chart, and histologic features of the hypertrophic dens were examined in the sagittally cut section. RESULTS: After posterior decompression surgery, cervical myelopathy in the patient subsided. Myelopathy reappeared 4 years after surgery. Imaging studies showed osteoarthritis of the atlantodental joint, hypertrophic dens, and degeneration of the cruciate ligament. In the second surgery, transoral removal of the dens with posterior occipitocervical fusion was performed. Histologic studies showed thickening of the cortical bone of the anterior and cranial parts of the dens. The apical portion, which was the insertion portion of the ala ligaments, showed degenerative changes of tide marks. CONCLUSION: Atlantoaxial instability and enthesopathy were probably the causes of the hypertrophic changes of the dens in this case.     

Surgical aspects of the cervical spine in rheumatoid arthritis

Approximately 20% percent of the patients with rheumatoid arthritis show pathology in the cervical spine. The translational instability between axis and atlas might be painful and leads in the long term to myelopathic changes due to chronic traumatization of the myelon. Ongoing osseous resorption of the lateral masses of the atlas cause upward migration of the dens into the foramen magnum. In the subaxial cervical spine, the inflammatory process causes instability and deformity. Neck pain is the most common indication for surgery, but neurological symptoms with myelopathy or radicular deficits might be the primary cause for surgery. Neurophysiological investigation is suitable to obtain objective results. Stabilization of the atlantoaxial segment is the most common procedure for treatment of atlantoaxial instability. It is performed by screw fixation technique from a posterior approach. In case of severe occipitocervical dislocation, the fixation has to be extended to the occiput. Persistent dislocation or compression by the dislocated dens has to be treated by transoral decompression. In the subaxial spine, instabilities may be treated by posterior plate fixation with lateral mass screws or pedicle screws. Concomitant nar-rowing of the spinal canal should be approached by anterior decompression with corpectomy and/or posterior laminectomy. The timing of surgery in rheumatoid patients is crucial to obtain satisfactory clinical results.     

Myelopathy due to hypertrophic nonunion of the dens: case report

Fractures which occur near the base of the dens have a low propensity to unite spontaneously. One of the major complications of nonunion is displacement of the fracture resulting in neuraxis compression and the development of myelopathy. Hypertrophic nonunion of the dens may cause spinal cord compression even if displacement does not occur. This situation has not to our knowledge previously been reported. A literature review and appraisal of the issues raised are discussed. Appropriate therapeutic options are outlined, including posterior surgery and the use of transoral decompression.     

The influence of transoral odontoid resection on stability of the craniovertebral junction.

Twenty-seven cases of craniovertebral junction compression treated with transoral surgery were reviewed to assess the influences of pathological processes and surgical interventions on spinal stability. All patients presented with signs and symptoms of spinal-cord or brain-stem dysfunction. Pathology included rheumatoid arthritis in 11 patients, congenital osseous malformations in 11, spinal fractures in two, plasmacytoma in one, osteomyelitis in one, and a gunshot injury in one. Instability was defined as clear radiographic evidence of mobile subluxation in conjunction with clinical assessment. Of 19 patients (70%) requiring internal fixation, nine underwent upper cervical fusion and 10 had occipitocervical fusion. When instability occurred, all subluxations were at the C1-2 level. There were no occipito-atlantal subluxations. Eight patients (30%) had preoperative instability of the craniovertebral junction due solely to their pathology, 11 patients (40%) suffered instability after transoral surgery, and eight (30%) were without clinical or radiographic evidence of instability (mean follow-up period 14 months). Craniovertebral junction instability predominated among patients with rheumatoid arthritis: 91% required fusion and 45% presented with pre-existing instability. Among individuals with congenital osseous malformations, 45% required fusion and only one patient (9%) had pre-existing instability. Patients who required subsequent posterior decompression of a Chiari malformation were at risk for developing instability; three of four became unstable after posterior decompression. Transoral resection of the dens, the anterior arch of C-1, and the lower clivus does not fully destabilize the spine; however, this operation may potentiate incipient pathological instability. The primary determinants of instability are the extent of pathological bone destruction, ligamentous weakening, and operative bone removal. Long-term follow-up monitoring is needed after transoral surgery to detect cases of late instability.     

经口咽前路枢椎体次全切除椎管减压术

目的：探讨经口咽前路枢椎体次全切除椎管扩大减压治疗寰枢椎脱位伴以C2后方脊髓受压为主的患者的疗效。方法：对12例先天畸形或外伤(10例先天畸形，2例外伤)引起的寰枢椎脱位伴高位脊髓压迫症患者，采用经口咽前路C2椎体次全切除术，11例仅行C2椎体次全切除，1例行C2椎体次全切除同时切除C1前结节和齿突。结果：无术中脊髓损伤、血管损伤及术后感染等并发症，术后平均随访18个月，按Symon和Lavender临床评定标准和影像学评定标准评定疗效，临床总有效率100％，显效率42％，术后影像学椎管减压改善率平均为75％。结论：该术式减压充分，是治疗以C2后方受压为主的脊髓压迫症较好的术式。     

Transoral decompression and posterior fusion for rheumatoid atlanto-axial subluxation

Cervical myelopathy is an uncommon but potentially fatal complication of rheumatoid atlanto-axial subluxation. Computerised myelotomography with three-dimensional reconstruction shows that rheumatoid pannus, together with the odontoid peg, contributes significantly to anterior cervico-medullary compression. These findings were the basis for treatment by transoral anterior decompression and posterior occipitocervical fusion, which removes both bony and soft-tissue causes of compression and allows early mobilisation without major external fixation. We report encouraging results from this combined approach in 14 patients who had progressive neurological deterioration.     

Chirurgische Aspekte der rheumatischen Halswirbelsäule

Approximately 20% percent of the patients with rheumatoid arthritis show pathology in the cervical spine, mainly in the atlantoaxial segment. The translational instability between axis and atlas might be painful and leads in the long term to myelopathic changes due to chronic traumatization of the myelon. Ongoing osseous resorption of the lateral masses of the atlas cause upward migration of the dens into the foramen magnum. In the subaxial cervical spine, the inflammatory process causes instability and deformity. Neck pain is the most common indication for surgery, but neurological symptoms with myelopathy or radicular deficits might be the primary cause for surgery. It has to be kept in mind that clinical assessment in rheumatoid patients might be extremely difficult since previous surgeries on various articulations of the extremities make interpretation of clinical findings difficult. Neurophysiological investigation is suitable to obtain objective results. Stabilization of the atlantoaxial segment is the most common procedure for treatment of atlantoaxial instability. It is performed by screw fixation technique from a posterior approach. In case of severe occipitocervical dislocation, the fixation has to be extended to the occiput. Persistent dislocation or compression by the dislocated dens has to be treated by transoral decompression. In the subaxial spine, instabilities may be treated by posterior plate fixation with lateral mass screws or pedicle screws. Concomitant narrowing of the spinal canal should be approached by anterior decompression with corpectomy and/or posterior laminectomy. The timing of surgery in rheumatoid patients is crucial to obtain satisfactory clinical results.     

Occipitocervical fusion in patients with rheumatoid arthritis

Instability and deformity of the cervical spine caused by rheumatoid arthritis is a well known entity. Operative intervention is indicated for patients with progressive deformity and when pain is resistant to conservative treatment. In a series of 39 patients who underwent posterior occipitocervical fusion with a Y plate, 22 patients were observed clinically and radiographically at average 41.5 months after surgery. In 35 of the 39 patients the main indication for surgery was pain, and in 30 of the 39 patients additional neurologic deficit (radiculopathy or myelopathy) was present. Thirty-one of the 39 patients had atlantoaxial instability. The atlantoaxial instability was associated with cranial migration of the dens in 19 patients. According to the classification of Conaty and Mongan 77.3% patients had satisfactory results and 22.7% had unsatisfactory results. Of the 30 patients with neurologic deficit, nine patients had a significant improvement. No patient had a worse result after surgery. Solid fusion was seen in all 22 patients at followup. Seven patients experienced complications directly related to the surgical procedure. Posterior fixation combined with anterior decompression in the presence of spinal stenosis represents a useful and safe method to treat instability and deformity caused by rheumatoid arthritis. Early surgical procedures may reduce the complication rate.     

Functional evaluation of the spinal cord by magnetic resonance imaging in patients with rheumatoid arthritis and instability of upper cervical spine

Thirty-four patients with atlanto-axial instability due to rheumatoid arthritis were examined with plain x-ray views and functional magnetic resonance imaging (MR), and were neurologically evaluated. Transcranial brain stimulation was performed in 25 patients. In 22 cases, the authors observed inflammatory tissue thicker than 3 mm behind the odontoid peg. The spinal canal diameter was significantly decreased in the flexed position. Nine patients showed signs of cranial migration of the axis. The diameter of the spinal cord was measured to be 7.4 mm in the neutral position, and 6.5 mm in flexion. The difference between the diameter of the neutral and flexed positions was highly significant. Twelve of the 34 patients displayed clinical signs of cervical myelopathy, and 13 showed a significant delay of central motor latency, as calculated from the motor evoked potentials. Surgical intervention, either by a posterior approach only or combined with a transoral dens and inflammatory tissue resection, is recommended in patients with progressive atlanto-axial instability, pathologic clinical and neurophysiologic findings, and a spinal cord diameter of less than 6 mm in flexion. Severe pain and cranial migration of the axis, as measured by the MRI, also justify a surgical intervention.     

寰枢椎脱位与不稳定388例住院病例分析

目的分析不同原因引起的寰枢椎脱位与不稳定的特点,为诊断、治疗的改进提供参考。方法对 1975年 1月～ 2000年 4月收治的寰枢椎脱位或不稳定患者 388例作回顾性分析。结果寰枢椎发育异常引起的寰枢椎脱位 262例,创伤性寰枢椎脱位 71例,其他原因 55例。发育异常中骨性畸形 238例,包括枢椎齿突发育异常、寰椎枕化、颅底凹陷等,以单纯枢椎齿突畸形最为多见,但出现脊髓损害的比例没有显著性差异。随着病史的延长出现脊髓损害的可能性增加,出现重症脊髓损害的可能性也明显增加。陈旧性骨折比新鲜骨折复位更困难。陈旧性骨折 (35例 )中有 19例伤后脊髓损害加重。伤后超过 1年的陈旧性骨折患者,症状加重的发生率明显高于病史不足 1年者。结论畸形等发育性异常导致寰枢椎脱位与不稳定比创伤性原因更常见,一旦出现临床症状应积极治疗。创伤性寰枢椎脱位患者应早期积极治疗,避免晚期脊髓损害加重。     

Acquired atlantoaxial instability in children with spastic cerebral palsy

The development of nontraumatic atlantoaxial instability in children with spastic cerebral palsy has not been reported. The authors present three patients with severe spastic quadriplegia who developed C1-C2 instability and cervical myelopathy at mean age 12.6 years. These patients demonstrated a similar clinical picture with symptoms attributed to cervical myelopathy in varied severity including apneic episodes, opisthotonus, alteration in muscle tone, torticollis, respiratory problems, hyperreflexia, and bradycardia. Patient 1 was scheduled for surgery but died due to an apneic episode. Patient 2 refused surgery and has been followed for 3 years while his neurologic condition remains unchanged. Patient 3 underwent occipitocervical decompression and fusion, recovered neurologically, and resumed his previous functional skills. Patients demonstrating considerable functional deterioration or insidious change in their established neurologic status should undergo detailed screening to rule out developing upper cervical instability. Early surgical intervention consisting of spinal decompression and fusion may prevent the development of myelopathy.     

Orion锁定型颈椎前路钢板系统的临床应用

目的 探讨Orion负定型颈椎前路钢板系统对颈椎骨折和脊髓型颈椎病手术固定的效果。方法 对3例颈椎骨折合并高位截瘫和2例脊髓型颈椎病患者施行颈椎前路减压植骨融合及Orion钢板内固定。结果 术后随访4－12个月,植骨已完全融合,无钢板断裂、螺钉松动等情况发生。结论 Orion锁定型颈椎前路钢板系统方法简单、容易掌握,内固定牢固,尤其适用于颈椎骨折伴高位截瘫患者的内固定治疗。     

Transoral fusion with internal fixation in a displaced hangman's fracture

STUDY DESIGN: A case is reported in which late displacement of a "hangman's fracture" was managed by transoral C2-C3 fusion by using bicortical iliac crest graft and a titanium cervical locking plate. OBJECTIVES: To review the management of unstable fractures of the axis and to study other reports of transoral instrumentation of the cervical spine. SUMMARY OF BACKGROUND DATA: Undisplaced fractures of the axis are considered to be stable injuries. Although late displacement is unusual, it can lead to fracture nonunion with persisting instability and spinal cord dysfunction. In this situation, an anterior fusion of the second and third cervical vertebrae is preferred to a posterior fusion from the atlas to the third cervical vertebra, which would abolish lateral rotation between C1 and C2. METHODS: The literature on hangman's fractures was reviewed. Clinical and radiographic details of a case of C2 instability were recorded, and the particular problems posed by late displacement were considered. RESULTS: There are no other reports of transoral instrumentation of the cervical spine. A sound fusion of C2-C3 was obtained without infection or other complications. Good neck movement returned by 6 months after surgery. CONCLUSION: Undisplaced fractures of the axis are not always stable. The transoral route allows good access for stabilization of displaced hangman's fractures. In special circumstances, a locking plate may prove useful in securing the bone graft. The cervical spine locking plate can be inserted transorally with no complications and by using standard instrumentation.     

Combined laminoplasty with posterior lateral mass plate for unstable spondylotic cervical canal stenosis--technical note

A technique of combined expanding laminoplasty using longitudinal interspinous iliac bone graft with posterior lateral mass plate is described for the treatment of cervical canal stenosis associated with spinal instability. A 52-year-old male and a 76-year-old female presented with cervical myelopathy. Imaging studies demonstrated spondylotic cervical canal stenosis associated with spinal instability. Posterior stabilization with lateral mass plate by the Axis Fixation System was performed after expanding laminoplasty using interspinous iliac bone graft. The symptoms improved and instability and malalignment (in the female patient) also improved after surgery. This combined surgical technique allows decompression of the spinal cord, immediate internal fixation by plate fixation, and subsequent long-term stabilization by interspinous bony fusion. This technique is indicated in selected patients with multiple segment spondylotic cervical canal stenosis associated with instability and/or malalignment of the spinal column for which simultaneous decompression and stabilization are required.     

高位颈椎的前路手术治疗

目的观察高位颈椎前路手术的临床效果,方法本组15例．男10例,女5例．年龄12—67岁。C1,2椎体结核3例．Hangman 7例,先天性齿状突不连伴难复性环椎脱位3例,齿状突骨折2例。本组经高位前方咽后入路显露C2-3,椎体结核患者行病灶清除术．先天性齿状突不连者行前路松解复位．后路环枢融合;Hangman骨折。复位后行C2,3椎间植骨融合术．放自锁钛板内固定,齿状突骨折行前路中空螺钉内固定。结果15例患者均成功地显露C1前弓至C3椎体,并完成病灶清除、复位、减压融合内固定：无颈部重要血管神经损伤,无伤口感染．9例不全瘫有部分恢复。结论高位前方咽后入路可充分显露上颈椎．高位颈椎前路术式能有效复位、减压和稳定,并可最大程度重建颈椎生理功能。     

Relationships between sagittal alignment of the cervical spine and morphology of the spinal cord and clinical outcomes in patients with cervical spondylotic myelopathy treated with expansive laminoplasty

A total of 103 patients with cervical spondylotic myelopathy undergoing laminoplasty were retrospectively reviewed to evaluate whether sagittal alignment of the cervical spine and morphology of the spinal cord influence surgical outcomes. Sagittal alignment of the cervical spine did not influence surgical outcomes. Neurologic recovery in patients with anterior convexity of the spinal cord was better than in those without this type of spinal cord. In patients with supplementation of decompression at C2, sagittal morphology of the spinal cord did not influence neurologic recovery. It is important to acquire anterior convexity of the spinal cord after surgery if laminoplasty is performed below C3. In patients with kyphosis, where anterior convexity of the spinal cord is not thought to be obtained postoperatively, it is possible that additional decompression of C2 improves outcome.     

Rheumatoid arthritis of the cervical spine. Current concepts for diagnosis and therapy

The involvement of the cervical spine in patients with rheumatoid arthritis (RA) is common,and has recently received growing attention. In the early stage of the disease, there is an isolated atlantoaxial subluxation (AAS). With further progression, osseous destruction of the joints can lead to vertical instability. While the involvement of the middle and lower cervical spine can cause a subaxial instability, neurological deficits can occur at any time. The onset of cervical myelopathy in patients with RA is often missed because of additional problems related to the hands and feet. If patients show clear symptoms of cervical myelopathy, the progression of the disease cannot be stopped by conservative treatment. Other indications for operative treatment are severe pain and radiological evidence of progressive instability. In the case of an isolated AAS, fusion can be restricted to the C1/C2 segment. If there is evidence for vertical or subaxial instability, an occipitocervical fusion has to be performed. To avoid instability adjacent to the fusion, the surgeon must check for signs of potential subaxial instability. If this is the case, fusion should include the entire cervical spine. Additional transoral decompression may be necessary when there is persistent retrodental pannus or osseous compression by an irreducible transverse dislocation or cranial migration of the dens. Non-ambulatory myelopathic patients are more likely to present severe surgical complications with limited prospects of functional recovery. Therefore, it is important to avoid the development of severe cervical myelopathy by early surgical intervention.     

颈前路钢板内固定治疗脊髓型颈椎病39例体会

目的观察颈前路钢板在脊髓型颈椎病手术中的作用和疗效。方法对39例脊髓型颈椎病患者行颈前路减压植骨、颈前路钢板内固定术,术后随访观察神经功能恢复情况、植骨融合率及有无植骨并发症。结果术后进行6—18个月（平均10个月）随访。症状明显缓解、脊髓功能明显改善者36例,占90％。术后8个月植骨融合率达到100％。无钢板断裂、螺钉松动、植骨不愈合、椎体高度丢失现象存在。结论应用颈前路减压植骨、颈前路钢板系统内固定术治疗脊髓型颈椎病具有以下优点：可获得术后颈椎即刻稳定,防止植骨块移位,手术时间短,术后无需行石膏固定,能显著提高植骨融合率。     

颈椎病伴椎管狭窄患者再手术问题探讨

目的：探讨颈椎病伴椎管狭窄患者再手术的原因、手术方式及其相关问题。方法：我院2002年7月～2003年12月对40例颈椎病伴椎管狭窄术后疗效不佳或症状复发的患者进行了后路多节段（5个或以上）减压手术。根据其手术治疗方式及影像学资料分析再手术原因，并进行术后疗效评价。结果：经前路手术者再手术的主要原因为：（1）伴有多节段颈椎管狭窄因素时，只选择部分压迫重的节段行减压融合15例；（2）经前路多节段（≥3个节段）减压融合后，相邻节段继续退变，出现新的脊髓压迫表现及椎间不稳定9例；（3）伴有OPLL时，行部分节段前路减压融合后，病变呈进展表现，产生或加重对脊髓的压迫8例。经后路手术者再手术的原因为：（1）后路减压节段不够5例（包括1例前后路联合手术者）；（2）后路减压不充分3例。再手术后随访1．3～2．7年，平均2．1年，所有患者脊髓功能获得一定的提高，JOA评分改善率为51．3％。结论：颈椎病伴椎管狭窄病例再手术的主要原因为椎管狭窄因素仍然存在，经后路多节段（5个或以上）减压手术治疗可彻底去除颈椎管狭窄因素，有效解除脊髓前、后方所受的压迫，可获得较满意的临床疗效。